Component-I
Component-IA (Personal Details)
Role Name Affiliation
Principal Investigator Dr. C.P. Mishra Professor
Department of Community Medicine Institute of Medical Sciences
Banaras Hindu University Varanasi, Uttar Pradesh, India Paper Coordinator Dr. C.P. Mishra Professor
Department of Community Medicine Institute of Medical Sciences
Banaras Hindu University Varanasi, Uttar Pradesh, India Content Writer/Author Dr. Madhutandra Sarkar Associate Professor
Department of Community Medicine Heritage Institute of Medical Sciences Varanasi, Uttar Pradesh, India
Content Reviewer Language Editor
Component-IB (Description of Module)
Items Description of Module
Subject Name Social Medicine and Community Health
Paper Name Human Nutrition
Module Name/Title Food Fortification and Enrichment
Module Id SMCH/HN/22
Pre-requisites Knowledge on micronutrients, their sources and deficiencies Objectives To study about food fortification and enrichment
Key words Micronutrients, Fortificants, Fortification, Enrichment, Foods, Vehicles
Component-II (e-Module)
Quadrant-I (e-Text) 1. Introduction
Micronutrients include vitamins, minerals, trace elements, phytochemicals and antioxidants.
Micronutrients are essential to sustain life, to maintain good health and for optimal physiological function. However, these are required in much smaller quantities in comparison to macronutrients (such as carbohydrate, fat and protein).
Deficiencies of micronutrients are a major global health problem1. Widespread micronutrient deficiencies exist in the world. Moreover, the incidences of micronutrient deficiencies continue to increase globally because of the increasing poverty and global food insecurity2. Micronutrient deficiency disorders are more common among economically deprived populations in the developing countries. However, underprivileged communities in the industrialised world are also vulnerable to these disorders. Poverty, lack of access to a variety of foods, lack of knowledge of appropriate dietary practices and high incidence of infectious diseases are the key factors, which can lead to micronutrient malnutrition.
The public health importance of these deficiencies lies upon their magnitude and their health consequences. More than 2 billion people worldwide are estimated to be affected by micronutrient deficiencies today. The most common deficiencies exist for vitamin A, folate, iron, iodine and zinc3. Children and pregnant women are especially vulnerable to the consequences of these deficiencies, i.e. foetal and child growth, cognitive development and resistance to infection4.
Micronutrient malnutrition has many adverse effects on human health, not all of which are clinically evident. Even moderate levels of deficiency (i.e. those detected only by biochemical measurements or detailed clinical examination) can have detrimental effects on physiological functions and the body systems. In addition to the obvious and direct health effects, the existence of micronutrient malnutrition has profound implications for economic and social development and productivity, particularly in terms of the potentially huge public health costs and the loss of human capital formation. Micronutrient malnutrition is a major impediment to socio-economic development and contributes to a vicious cycle of malnutrition, underdevelopment and poverty affecting already underprivileged groups. Overcoming micronutrient malnutrition is a precondition for ensuring rapid and appropriate national development4.
Micronutrient deficiencies are preventable. However, prevention of these deficiencies is critical and traditionally has been accomplished through supplementation, fortification and food-based approaches including diversification. However, over the long term, food fortification may offer a more effective means to address micronutrient deficiencies, as it enables a larger segment of a population to be targeted. Fortification is the practice of deliberately adding one or more essential micronutrients (i.e. vitamins, minerals and trace elements) to a particular food to improve the nutritional quality of that food. Fortification should provide public health benefits with minimal or no risks to human health. Enrichment is defined as synonymous with fortification, and refers to the addition of micronutrients to a food, which are lost during processing. The aim of fortification/ enrichment is to increase the intake of these micronutrients to correct or prevent deficiencies and to provide health benefits. A wide array of fortifying agents (fortificants) and food carriers (vehicles) have been developed to date.
2. Learning Outcomes
After completing this module, the students will be able to:
1. define food fortification, enrichment and other related terms
2. understand the potential for micronutrient fortification and list the types of fortification
3. elaborate the historical development and current practices related to food fortification
4. describe the development of a successful food fortification programme 5. understand the technological issues related to food fortification
6. explain briefly the regulatory monitoring of food fortification programmes
3. Food Fortification and Enrichment: Details
3.1. Food Fortification, Enrichment and Other Related Terms: Definitions
While both fortification and enrichment refer to the addition of nutrients to food, the true definitions do slightly vary. Enrichment is done to restore lost nutrients to food, whereas fortification is done to increase nutritional value of food.
Food fortification has been commonly defined as the addition of one or more essential nutrients to a food, whether or not it is normally contained in the food, for the purpose of preventing or correcting a demonstrated deficiency of one or more nutrients in the population or specific population groups. Some examples of food fortification are milk fortified with vitamin D, salt with iodine, water or toothpaste with fluoride, flour with folic acid, calcium with fruit juice, etc.
Enrichment is defined as synonymous with fortification, and refers to the addition of micronutrients to a food, which are lost during processing. Enrichment is the addition of nutrients to foods in accordance with a standard of identity as defined by food regulations. For example, white bread enriched with vitamins and minerals.
The goal for any food fortification is to increase the nutrient intake for the target population to as close as possible to the recommended intake, while at the same time maintaining safe levels of intake for all persons.
Several other terms besides fortification and enrichment are used for the addition of nutrients to foods, i.e. restoration, substitution, standardisation and supplementation.
Restoration is the addition of a nutrient to a food in order to restore the original nutrient content. In this process, nutrients lost during food processing are replaced. For example, B vitamins are added to white flour, as they are removed with the bran during the milling of wheat to make white flour.
Both restoration and enrichment programmes usually involve the addition of nutrients that are naturally available or present in the food product.
Substitution is the addition of nutrients to produce a substitute product with similar nutritive value. For example, some soya based drinks sold as a substitute for cow’s milk may have calcium voluntarily added.
Standardisation is the addition of nutrients to foods to compensate for natural variation, so
that a standard level is achieved. It is an important step to ensure a consistent standardised quality of the final product. A typical example is the addition of vitamin C to orange juice to standardise vitamin C concentration and compensate for changes due to seasonal and processing variations.
Supplementation is the addition of nutrients that are not normally present or are present in only minute quantities in the food. More than one nutrient may be added, and they may be added in high quantities. Supplementations can be given as tablets, capsules, powders, liquids, etc.
Nitrification is the addition of nutrients to foods at such a level as to make a major contribution to the diet. It means making a dietary mixture or a food more nutritious.
Double fortification: This term is used when two nutrients are added to a food or food mixture.
Multiple fortification: This term is used when more than two nutrients are added to a food or food mixture.
Vehicle: The food that carries the nutrient is the vehicle.
Fortificant: The nutrient added to the food is called the fortificant.
As compared with restoration and standardisation, fortification has a special meaning - the nutrient added and the food chosen as a carrier have met certain criteria, so that the fortified product will become a good source of the nutrient for a target population. Nutrients added for food fortification may or may not have been present in the food carrier originally.
3.2. The Potential for Micronutrient Fortification5
There are four primary intervention measures for addressing micronutrient deficiency, i.e.
biofortification, food fortification, supplementation and dietary diversity, besides health education and other public health measures.
Fig. 1: Primary Intervention Measures for Micronutrient Deficiencies
Source: http://projecthealthychildren.org/why-food-fortification/
The fortification of foods is a widely used method for the delivery of micronutrients. The food utilised for fortification can be selected to deliver the nutrient(s) to a target population effectively, uniformly, safely and at minimum cost. Fortification programmes have been effectively implemented in both developed and developing countries to provide a variety of nutrients. Many different foods have been used as vehicles.
The practice of adding essential nutrients to foods was first introduced in the 1920s to reduce deficiency disorders, which were prevalent at that time in the United States and Europe. Food fortification has most likely played an important role in the decline of deficiency diseases, e.g.
niacin fortification of flour and bread in the elimination of pellagra, iodine fortification of salt in the decline of goitre, vitamin D fortification of margarine and milk in the disappearance of rickets, and more recently, folic acid fortification of cereal products in the decline of neural tube defects.
Over the last couple of decades, there has been a steep increase in the fortification programmes in the developing countries. From a public health perspective, food fortification should serve the nutritional needs of the population. The risk and benefit of food fortification is a function of the distribution of the nutritional requirements and susceptibility to toxicity, neither of which are well characterised for most nutrients. Fortification has the distinct advantage of requiring less change in consumer behaviours than the other nutrient interventions.
The nutritional status of the population is one of the important factors determining the quality and productivity of the population, which in turn affects national productivity. Good nutritional status, in the long term, contributes to the intelligence and health of the population. This also contributes to the social and economic development of a nation6.
3.3. Types of Fortification4
There are several forms of food fortification. These are as follows:
3.3.1. Mass fortification: This term is used to describe the addition of one or more micronutrients to foods commonly consumed by the general population, such as cereals, milk and condiments. Sometimes it is called “universal fortification”. Mass fortification is nearly always mandatory. It is usually instigated, mandated and regulated by the government sector. This type of fortification is generally the best option when the majority of the population, in terms of public health, is at an unacceptable risk of specific micronutrient deficiency. In some situations, specific micronutrient deficiency may be demonstrable, as evidenced by biochemical or dietary criteria. In others, the population may not actually be deficient, but are likely to benefit from fortification. For example, the mandatory addition of folic acid to wheat flour with a view to lowering the risk of birth defects, as practised in Canada, the United States and also in many Latin American countries.
3.3.2. Targeted fortification: In targeted food fortification programmes, foods aimed at specific population subgroups are fortified, thereby increasing the intake of that particular group rather than that of the population as a whole. Examples include complementary foods for infants and young children, foods developed for school feeding programmes, special biscuits for children and pregnant women and rations (blended foods) for emergency feeding and displaced persons. Targeted fortification can be either mandatory or voluntary depending on the public health significance of the problem it is seeking to address.
3.3.3. Market-driven fortification: This term is applied to situations whereby a food manufacturer takes a business-oriented initiative to voluntarily add specific amounts of one or more micronutrients to processed foods available in the market place. It is sometimes called “industry-driven fortification”, “open-market” or “free-market”
fortification. Market-driven fortification can play a positive role in public health by contributing to meeting nutrient requirements and thereby reducing the risk of micronutrient deficiency. This type of fortification is always voluntary, but governed by government-set regulatory limits. Market-driven fortification is more widespread in industrialised countries, whereas its public health impact is still limited in most developing countries. However, increasing urbanisation and wider availability of fortified processed foods in developing countries has given rise to a number of concerns, e.g. diversion of consumers from their usual dietary patterns and excessive intake of micronutrients due to scant regulatory attention.
3.3.4. Other types of fortification
3.3.4.1. Household and community fortification
Efforts are under way in a number of countries to develop and test practical ways of adding micronutrients to foods at the household level, in particular, to complementary foods for young children. In effect, this approach is a combination of supplementation and fortification, and has been referred to by some as “complementary food supplementation”. The efficacy and effectiveness of several different types of products, including soluble or crushable tablets, micronutrient-based powder (“sprinkles”) and micronutrient-rich spreads are currently being evaluated. Crushable tablets and especially micronutrient-based powder are relatively expensive ways of increasing micronutrient intakes, but may be especially useful for improving local foods fed to infants and young children, or where universal fortification is not possible.
Fortification of foods at the community level is also still at the experimental stage. The major challenges include initial cost of the mixing equipment, the price of the micronutrient premix, achieving and maintaining an adequate standard of quality control and sustaining monitoring and distribution systems.
3.3.4.2. Biofortification of staple foods
Biofortification of staple foods, i.e. the breeding and genetic modification of plants so as to improve their nutrient content and/or absorption is another novel approach that is currently being considered. The potential for plant breeding to increase the micronutrient content of various cereals, legumes and tubers certainly exists. For instance, it is possible to select certain cereals (such as rice) and legumes for increasing their iron content, various varieties of carrots and sweet potatoes for their favourable β-carotene levels, and maizes for their low phytate content (which improves the absorption of iron and zinc). However, much more work still needs to be done before the efficacy and effectiveness of these foods are proven, and current concerns about their safety, cost and impact on the environment are alleviated.
3.4. Fortification of Foods: Historical Development and Current Practices4, 7, 8
A Persian physician Melanpus first mentioned nutrient supplementation of foods in the year 400 B.C. He suggested adding iron filings to wine to increase soldiers' potency. In 1831, a French physician Boussingault urged adding iodine to salt to prevent goitre. However,
supplementation was established as a measure either to correct or prevent nutritional deficiencies in populations or to restore nutrients lost during food processing between the First and Second World Wars (1924-1944). The addition of iodine to salt, vitamins A and D to margarine, vitamin D to milk, and vitamins B1, B2, niacin and iron to flours and bread was established during this period.
The words “enrichment” and “fortification” have historical origins. Enrichment was originally introduced in the 1940s with enactment of the Standards for Enrichment Programmes aimed at replenishing nutrients lost during cereal processing. This was expanded into a broader context to include nutrients not naturally present in the food, or fortification. Currently, the two words are often used interchangeably, which is wrong from a historical standpoint. However, taking into consideration the fact that the aim in both cases is to improve the nutritional value of foods, the term “nitrification” was suggested, which would include both enrichment and fortification.
In industrialised countries, food fortification has a long history of use for the successful control of deficiencies of vitamins A and D, several B vitamins (thiamine, riboflavin and niacin), iodine and iron. Salt iodisation was introduced in the early 1920s in both Switzerland and the United States of America and has since expanded progressively all over the world to the extent that iodised salt is now used in most countries. From the early 1940s onwards, the fortification of cereal products with thiamine, riboflavin and niacin became common practice. Margarine was fortified with vitamin A in Denmark and milk with vitamin D in the United States. Foods for young children were fortified with iron, a practice that has substantially reduced the risk of iron-deficiency anaemia in this age group. In more recent years, folic acid fortification of wheat has become widespread in the Americas, a strategy adopted by Canada and the United States and about 20 Latin American countries.
In the less industrialised countries, fortification has become an increasingly attractive option in recent years. Given the success of the relatively long-running programme to fortify sugar with vitamin A in Central America, where the prevalence of vitamin A deficiency has been reduced considerably, similar initiatives are being attempted in other world regions.
Despite apparent past successes, to date, very few fortification programmes have formally evaluated their impact on nutritional status. However, without a specific evaluation component, once a fortification programme has been initiated, it is difficult to know whether subsequent improvements in the nutritional status of a population are due to the intervention or to other changes (such as, improvements in socioeconomic status or in public health provision), that occurred over the same period of time. Evidence that food fortification programmes do indeed improve nutritional status has therefore tended to come from either efficacy trials and/or reports of programme effectiveness.
Efficacy trials, i.e. trials conducted in controlled feeding situations, are relatively numerous and have usefully documented the impact of fortified foods on nutritional status and other outcomes. Efficacy trials evaluate the impact of a test intervention under ideal circumstances.
In the case of food fortification, this typically involves all test subjects consuming a known amount of the fortified food. In the majority of efficacy trials conducted to date, fortified foods have been shown to improve micronutrient status.
Evidence of programme effectiveness, which is obtained by assessing changes in nutritional status and other outcomes once a programme has been implemented, is less widely available.
The aim of an effectiveness evaluation is to assess the impact of an intervention or programme in actual practice, as opposed to under controlled conditions. Because of factors such as the lack of consumption of the fortified food, the magnitude of the impact of an intervention is likely to be less than that in an efficacy trial.
Currently, food fortification encompasses a broader concept. It might be done for several reasons, e.g.:
- to restore nutrients lost during food processing (enrichment). In this case, the amount of nutrients added is approximately equal to the natural content in the food before processing.
- to add nutrients that may not be present naturally in food (fortification). In this case, the amount of nutrient added may be higher than that present before processing.
- to standardise the contents of nutrients that show variable concentrations (standardisation).
- to add a preservative or colouring agent to processed foods for technological purposes.
Depending on the reasons for adding nutrients, the objectives of fortification may be:
- to maintain the nutritional quality of foods, keeping nutrient levels adequate to correct or prevent specific nutritional deficiencies in the population at large or in groups at risk of certain deficiencies (i.e. the elderly, vegetarians, pregnant women, etc.).
- to increase the added nutritional value of a product (commercial view).
- to provide certain technological functions in food processing.
According to these principles, currently in several countries nutrients are added to a wide variety of food carriers, such as cereals, flours, bread, milk, margarine, infant formulas, soy milk, orange juice, salt, sugar, monosodium glutamate, tea, dietetic beverages, and even parenteral and enteral solutions (table 1). Most fortifying agents are vitamins and minerals, and in some cases essential amino acids and proteins9.
Table 1: Fortified Foods
Foods Fortifying Agent
Salt Iodine, Iron
Flours, Bread, Rice Vitamins B1, B2, Niacin, Iron
Milk, Margarine Vitamins A and D
Sugar, Monosodium glutamate, Tea Vitamin A
Infant formulas, Cookies Iron
Vegetable mixtures, Amino acids, Proteins Vitamins, Minerals
Soy milk, Orange juice Calcium
Ready-to-eat cereals Vitamins, Minerals
Diet beverages Vitamins, Minerals
Enteral and parenteral solutions Vitamins, Minerals
3.5. Development of a Successful Food Fortification Programme4, 6, 7, 10
The main goal of a fortification programme is to correct inadequate micronutrient intakes through the fortification of foods, thereby preventing, or reducing, the severity and prevalence of micronutrient deficiencies. Interventions of this nature can involve either fortifying a single food product (e.g. the iodisation of salt) or the fortification of several foods.
The dietary goal of fortification is formally defined as follows: to provide most (97.5%) of individuals in the population group(s) at greatest risk of deficiency with an adequate intake of
specific micronutrients, without causing a risk of excessive intakes in this or other groups.
Food fortification is one of the most popular nutritional interventions for improving the population’s nutritional status. The addition of nutrients to specific foods is based on the dietary habits and nutritional status of the target population. A good fortified product should not cause nutrition imbalance, and excessive intake of nutrients should not have adverse effects.
Food fortification programme is a nutritional intervention programme with a specifically defined target, and fortified food products are expected to become a main source of the specific added nutrient. Consequently, food fortification is expected to help prevent nutritional inadequacy in target populations in which a risk of nutrient deficiency has been identified.
The criterion of the effectiveness of a food fortification programme is whether the nutritional and health status of a targeted population has been improved. The effectiveness of a food fortification programme depends on whether or not the fortified food is accepted, purchased and consumed by the targeted population. Factors such as the quality, taste and price of the fortified products will play important roles in determining the effectiveness of the fortification programme. Several other important factors also should be taken into consideration in designing food fortification programmes.
Several important aspects of developing effective food-fortification programmes are:
(a) Choice of food carrier: The carrier has to be a staple food of the target population. Also, centralised processing is necessary, and frequent as well as reasonably constant consumption is desirable. The food chosen as the carrier should be consumed in sufficient quantities to make a significant contribution to the diet of the target population. Salt, sugar, flour, monosodium glutamate (MSG) and cooking oil have been used. Other foods should be explored, especially with reference to the specific food habits and preferences of targeted populations.
(b) Nutrient interactions, bioavailability of nutrients, stability of nutrients and safety: The addition of nutrients should not create an imbalance of essential nutrients. This is especially important for doubly, triply, or multiply fortified foods, in which interaction among the added nutrients (and also among the added nutrients and the nutrients that are naturally present in the food carrier) is likely to occur. Bioavailability is extremely important. The added nutrient should be stable under normal conditions of storage and use. Data on the stability of the added nutrient are also important for labelling purposes.
(c) Physicochemical and organoleptic characteristics: The nutrient or fortifying agent must have adequate physicochemical (optical, rheological, stability and flavour) and organoleptic (colour, taste, odour and appearance) characteristics. This means that the above properties of the carrier food must not be affected.
(d) Cost: Another important issue is related to the cost of the fortifying agent. It is desirable that the fortification process does not significantly increase the total cost of the final product. The price of the fortified food should be affordable for the targeted population.
(e) Monitoring and control: It is necessary to have a monitoring and control system that guarantees both adequate nutrient concentration and programme compliance. It is also important to verify the adequate addition of nutrients to ensure the programme's effectiveness, and, in the case of potentially toxic nutrients, to guarantee that excessive concentrations are not added, which could put the population at risk. Several questions must be answered in relation to legal issues. Programmes of quality assurance and control of fortified food can be more easily implemented if the fortification programme is
centralised and involves mass production.
(f) Distribution: The food should be distributed to as much of the target population as possible.
Box 1: Steps in the Development of a Food Fortification Programme 1. Determine the prevalence of micronutrient deficiency.
2. Segment the population if prevalence data indicate the need.
3. Determine the micronutrient intake from a dietary survey.
4. Obtain consumption data for potential vehicles.
5. Determine micronutrient availability from the typical diet.
6. Seek government support (policymakers and legislators).
7. Seek food industry support.
8. Assess the status of potential vehicles and the processing industry chain (including raw material supply and product marketing).
9. Choose the type and amount of micronutrient fortificant or mixes.
10. Develop the fortification technology.
11. Perform studies on interactions, potency, stability, storage and organoleptic quality of the fortified product.
12. Determine bioavailability of the fortified food.
13. Conduct field trials to determine efficacy and effectiveness.
14. Develop standards for the fortified foods.
15. Define final product and packaging and labelling requirements.
16. Develop legislation and regulation for mandatory compliance.
17. Promote campaigns to improve consumer acceptance.
3.6. Technological Issues Related to Food Fortification6, 7, 11
Food science and technology play a key role with respect to several issues, i.e. bioavailability of nutrients, stability of nutrients, nutrient interactions and safety.
3.6.1. Bioavailability of nutrients
It is necessary to maintain the overall quality of the product in terms of the bioavailability of the fortifying agent. Although bioavailability may increase, the product's quality is at risk, especially its stability. Iron, for example, may react with fatty acids in the fortified food, forming free radicals that induce oxidation. Other characteristics that may be affected are colour, taste, odour and appearance, alterations that should be avoided altogether since they affect consumer acceptability of the product.
This phenomenon, typical in mineral salts, is related to the solubility of the fortifying agent. In general, as solubility of the compound increases, the nutrient is more bioavailable, but at the same time is more reactive with the fortified food, making it less stable and susceptible to the changes described.
Iron salts, potentially useful in food fortification, could be divided into different categories.
First, the compounds that are soluble in water, such as ferrous sulphate and ferrous gluconate, show the highest bioavailability. However, they can easily alter the quality of most foods (stability, colour, odour), and are used only in infant formulas.
Second are compounds that are slightly soluble in water and soluble in diluted acids, for example, ferrous fumarate and ferrous succinate. These compounds have quite good bioavailability in relation to ferrous sulphate. But they still have significant limitations when added to food, except when added to infant cereals, where relative success has been achieved.
Third, compounds that are insoluble in water and slightly soluble in diluted acids, such as iron salts, are more inert and have low reactivity with the food carrier. Therefore, they are likely to be used as fortifying agents. Unfortunately, for the same reasons, they are less bioavailable.
For example, ferric salts such as ferric pyrophosphate and ferric orthophosphate are widely used in foods even though their bioavailability is low. However, several compounds of elemental iron that are reduced by different technological processes have higher bioavailability, and at the same time cause no significant changes in food characteristics.
In case of many of the water-soluble vitamins, practice of coating does offer protection against interaction with the food medium and development of organoleptic problems. However, it can create other difficulties. Slow dissolution of the coating in the gastrointestinal tract in order to free the active component can cause reduced bioavailability of the micronutrient. Care should therefore be taken in the use of such preparations so that the nutritional objectives are being met.
3.6.2. Stability of nutrients
Nutrient stability under normal conditions of storage and use is one of the important factors determining the effectiveness of a food fortification programme. From a technical standpoint, nutritional stability during formulation, preparation and processing is very crucial in determining the effective production of fortified foods. A good example is vitamin C, which is extremely unstable under several conditions, especially in high heat and humidity. Nutrient stability is affected by a wide range of physical and chemical factors. Changes in nutrients' stability may depend on factors such as pH, oxygen, air, light and temperature. Although many factors may cause serious nutrient degradation, measures can be developed to minimise losses by applying proper technology, which includes application of a protective coating for an individual nutrient, addition of antioxidants, control of temperature, moisture and pH, and protection from air, light and incompatible metals during processing and storage.
Fig. 2: Factors Influencing the Stability of Nutrients
Source: http://archive.unu.edu/unupress/food/V192e/ch03.htm
Percentage loss of different vitamins during processing and storage may be significant, especially for vitamins C, A, folic acid and niacin. It is useless to fortify foods if the nutrient concentration decreases after fortification, so that when the food is consumed the nutrient is no longer present.
Compared with vitamins, minerals (iron and iodine) are very stable under extreme processing conditions. The primary mechanism of loss of minerals is through leaching of water-soluble materials. Vitamin A, on the other hand, is very labile in the processing environment. Vitamin A is both oxygen and temperature sensitive. In the form of retinol, vitamin A is more labile than its ester form. For this reason, vitamin A esters are usually used for food fortification. The stability of vitamin A is also strongly affected by pH. At a pH of less than 5, vitamin A is susceptible to oxidation. At low pH, vitamin A tends to isomerise from the trans to the cis configuration, which has a lower vitamin activity. The problem of low pH is encountered especially during juice processing. Fruit juices usually have a low pH (about 3.0). To compensate for low pH, carbonation, which expels oxygen, may be used to stabilise vitamin A.
3.6.3. Nutrient-nutrient interactions
When more than one fortificant is being added to a particular vehicle, consideration must be given to the nutrient-nutrient interactions, both positive and negative, which could take place.
An example of this is seen with vitamin C and iron. Vitamin C has been shown to improve the absorption of iron. Other studies have indicated that iron and other trace metals increase the rate of ascorbic acid destruction. The presence of vitamin E has been shown to increase the bioavailability of vitamin A. Calcium has also demonstrated an inhibitory effect on iron absorption. Phosphorous negatively influences calcium absorption. In solutions of the B-vitamins, riboflavin can cause the oxidation and consequent loss of thiamine. If ascorbic acid is included into the solution the reaction does not occur. This observation is of practical significance in cases where solutions of water-soluble vitamins are sprayed onto foods during the fortification process. Riboflavin has also been implicated in oxidative loss of vitamin C.
Light-induced vitamin C loss from milk is reduced in the absence of riboflavin.
3.6.4. Nutrient-matrix interactions
Besides nutrient-nutrient interactions, other components of the food matrix may also affect the functionality of the fortificant (nutrient-matrix interactions). Selection of the vehicle in fortification programmes must be such that it avoids reduced bioavailability of nutrients due to the presence of anti-nutritional compounds. Some interactions of added nutrients with the food matrix have been noted but are poorly understood. For example, the absorption of iron from sugar fortified with ferric orthophosphate and ascorbic acid was shown to be greatly improved when added to maize porridge before cooking as compared with after cooking.
lodisation of salt and the compounds used for this have been widely studied in relation to the stability of the fortified salt. More research may be required if iodisation of processed foods through the use of iodised salt is to be widely practised. The available information on this topic has shown no problems with off-flavour and off-colour development in many common processing applications such as vegetable fermentation, production of fresh pack pickles and canning of vegetables. In some specific cases, however, the use of iodised salt might be problematic. More information is needed on the stability of iodised salt under conditions experienced in vegetable fermentations.
3.6.5. Monitoring and control
As part of the fortifying process, a permanent monitoring system of nutrient concentrations is extremely important to ensure the required levels, since high or low concentrations are unacceptable owing to the potential risk of toxicity. Legal issues are important and must be addressed so that country regulations are adhered to, facilitating the implementation of regional fortification.
3.7. Properties of Micronutrient Compounds Used in Food Fortification11, 12
Prudent handling of vitamin and mineral additives in food processing requires a sound understanding of the characteristics of these compounds, i.e. their stabilities to various unit operations, solubilities and reactivities with other compounds. Many forms of these nutrients have been developed to render them more suitable for use under a wide range of applications.
We will discuss the properties of three major micronutrients, i.e. iodine, iron and vitamin A.
3.7.1. Iodine
The most commonly used compounds in the iodisation of foods are the iodides and iodates of sodium and potassium. The iodide compounds are cheaper, more soluble and have higher iodine content than the corresponding iodates, so less is needed to achieve the same level of iodisation. Iodates are more stable under conditions of high moisture, high ambient temperature, sunlight, aeration and the presence of impurities. The use of iodate is therefore recommended for use in developing countries. Potassium iodide is well suited in cases where the salt is dry, free from impurities and has a slightly alkaline pH.
Salt is one of the most suitable vehicles for iodine fortification for the general population.
Alternative vehicles that may be considered for iodisation are milk, bread, flour, sugar and condiments. Suitable technologies for iodisation of salt exist for both large and small-scale production plants. There have been four major technologies used in the addition of iodine to salt. These are dry mixing, drip feed addition, spray mixing and submersion. In cases where there is more than one demonstrated micronutrient deficiency in a target population, the addition of more than one micronutrient to a single vehicle (multiple fortification) could be advantageous. Countries with effective iodised salt programmes have shown sustained reductions in IDD (iodine deficiency disorders) prevalence. In hyperendemic areas where immediate action is needed and/or where logistical problems could delay the development of iodisation programmes, the administration of iodised oil either by injection or orally, is the alternative strategy.
Sporadic reports of thyrotoxicosis have been reported especially in iodine fortification programmes, which were poorly monitored. Monitoring of any iodine fortification programme by quality assurance of the fortification process and periodic evaluation of urinary iodine status are of critical importance in ensuring the success and long term sustainability of any such programme.
3.7.2. Iron
Cereals are the most widely used vehicles for iron fortification although many others, such as milk products, sugar, curry powder, soya sauce and cookies have been successfully used.
Selection of an appropriate iron fortificant for any given application is based on the following criteria, i.e. organoleptic considerations, bioavailability, cost and safety. Elemental iron (particularly micronised), iron sulphate and iron fumarate are examples of preferred iron fortificants. Selection of the iron fortificant is dependent on the food vehicle. The colour of iron compounds is often a critical factor when fortifying light-coloured foods. For example, white iron, ferric orthophosphate, is often the fortificant of choice in the enrichment of rice.
The use of more soluble iron compounds (e.g. iron sulphate) often leads to the development of off-colours and off-flavours due to reactions with other components of the food material, but they have the advantage of being highly bioavailable. Infant cereals have been found to turn grey or green on addition of ferrous sulphate. Off-flavours can be the result of lipid oxidation catalysed by iron. The iron compounds themselves may contribute to a metallic flavour. Some of these undesirable interactions with the food matrix can be avoided by coating the fortificant with hydrogenated oils or ethyl cellulose.
The presence of phytates, polyphenols and calcium are known to adversely affect the bioavailability of non-haem iron fortificants. Increasing evidence indicates that in such cases sodium iron-EDTA may prove to be a better choice of fortificant in the future as iron from the EDTA-complex remains bioavailable even in the presence of iron absorption inhibitors.
Iron compounds used in food fortification are commonly classified according to their solubility, i.e. water soluble, poorly water soluble but soluble in dilute acid, water insoluble and poorly soluble in dilute acid. Bioavailability of iron compounds is normally stated relative to a ferrous sulphate standard. The highly water-soluble iron compounds have superior bioavailability. Bioavailability of the insoluble or very poorly soluble iron compounds can be improved by reducing particle size. Unfortunately this is accompanied by increased reactivity in deteriorative processes.
The problem of low bioavailability of some of the less reactive forms of iron is often circumvented by the use of absorption enhancers added along with the fortificant. Examples of such enhancers are ascorbic acid, sodium acid sulphate and orthophosphoric acid.
Given the wide variability of iron bioavailability, influenced by physical and chemical properties of the fortificant as well as the presence of substances which either inhibit or improve iron absorption, there is a need to develop convenient models for the evaluation of iron bioavailability.
Iron fortification practices should be based on feedback from comprehensive surveillance programmes monitoring their impact on iron status. It is important to assess the contribution of iron fortification in combination with other strategies for the control of iron deficiency in specific age/sex groups, so as to establish optimal goals for iron fortification of foods.
Surveillance data of iron status should be interpreted with caution because of the known alteration of serum ferritin levels and other indicators of iron status in the presence of recent infection. Serum transferrin receptor determination appears promising in the evaluation of iron status in the presence of infection.
Several aspects of the interaction between iron and other nutrients, such as vitamin A, iodine, zinc and calcium, need to be investigated in relation to the possibility of multiple fortifications.
The stability and the cost of fortificant compounds as well as the bioavailability of the nutrients need to be considered. The meal composition and dietary variety are important factors in optimising iron status.
3.7.3. Vitamin A
Foods that have been successfully fortified with vitamin A include margarine, fats and oils, milk, sugar, cereals and instant noodles with spice mix. Moisture contents in excess of about 7- 8% in a food are known to adversely affect the stability of vitamin A. Beyond the critical moisture content there is a rapid increase in water activity, which permits various deteriorative reactions to occur. Repeated heating, as may be experienced with vegetable oils used for frying, is known to significantly degrade vitamin A. The hygroscopic nature of salt has prevented its use as a vehicle for vitamin A fortification in countries of high humidity. In trying to overcome this problem, a new vitamin A fortificant, encapsulated to provide an additional moisture barrier, was evaluated with limited success. The cost of using highly protected fortificants can be prohibitive in many cases. In developed countries, vitamin A fortification is limited to milk and dairy products, margarine and fat spreads and breakfast cereals. Current levels of fortification of vitamin A are generally considered as safe.
Carotenoids can be used as a source of vitamin A. However, the conversion and bioavailability of the carotenoids are known to be affected by the vitamin A status of the individual and by dietary composition. A conversion factor of 6:1 (six milligrams of beta carotene equivalent to one milligram of retinol) is currently being applied in calculating intake. The cost factor in using carotenoids as the source of vitamin A activity in fortification is generally considered prohibitive.
Naturally occurring vitamin A is insoluble in water but soluble in oil. In this form the vitamin has limited applicability. Vitamin A fortificants are commercially available in a wide range of forms adapted for use under various conditions. For use in fat or oil based foods such as margarines, oils and dairy products, vitamin A as the acetate or palmitate have been used. They are stabilised with a mixture of phenolic antioxidants or with tocopherols. For mixing with dry products, a dry form of the fortificant was required with the appropriate size and density.
Encapsulation of the vitamin in a more hydrophilic coat is commonly practised in order to achieve a more water dispersible product. Two materials used in encapsulation are gum acacia and gelatin. These dry forms of the vitamin are also stabilised using tocopherols or phenolic antioxidants.
3.8. Cost versus Benefit of Food Fortification13, 14
The Copenhagen Consensus15 estimates that every $1 spent on fortification results in $9 in benefits to the economy. An initial investment is required to purchase both the equipment and the vitamin and mineral premix, but overall costs of fortification are extremely low. Even when all the programme costs are passed on to consumers, the price increase is approximately 1-2%, less than normal price variation.
Table 2: Cost versus Benefit
Source: http://projecthealthychildren.org/why-food-fortification/
Fortification with iron, iodine and potentially zinc provides significant economic benefits, and the low unit cost of food fortification ensures large benefit:cost ratios, with effects via cognition being very important for iron and iodine. Fortification is most attractive as an investment where there is a convenient food vehicle, where processing is more centralised, and where either the deficiency is widespread or the adverse effects are very costly even though only a small group is affected.
Economic analysis suggests that fortification is a very high-priority investment. It works well if there are widespread deficiencies (e.g. iron) and/or if the cost of the fortificant is not too high. Fortification is particularly attractive if the cost of the deficiency is very high and it is not easy to reach the target group (women in the periconceptional period). This applies particularly for folic acid and iodine. However, fortification cannot solve all micronutrient problems. The aim is to diversify people’s diets such that most of their needs can be met from food.
3.9. Risks vs. Benefits of Fortification16
Although there is risk in not obtaining adequate nutrients in the diet, there is also concern about whether individuals are consuming nutrients in excess. For some nutrients (e.g. zinc and copper), the window of safety between the values of EAR (estimated average requirement) and UL (tolerable upper intake level) for what represents an adequate intake vs. an excessive intake is relatively small, the difference being a factor of 4.
Despite ULs having been defined for many nutrients, the consequences of chronically high intakes from fortified foods and/or supplements is not known. Moreover, the consumption of fortified foods and supplements is correlated - people with high intakes of fortified food tend to also use supplements. The consumption of fortified foods results in a higher probability of nutrient intakes near or above the UL, as does the intake of supplements. Expanded
fortification can be expected to affect the upper tails of intake distributions the most. Whether discretionary fortification (i.e. addition of vitamins and minerals to foods at the discretion of manufacturers for marketing purposes, but not as part of a planned public health intervention) is beneficial depends on which foods manufacturers fortify, which nutrients are chosen as fortificants, how much of the fortificant is added, and what portion of the population consumes the fortified products.
Individual differences can affect the outcome of fortification. Numerous gene polymorphisms can alter the digestion, absorption and metabolic responses of individuals to certain nutrients.
Fortification with folic acid was initiated in part because of the identification of a high prevalence of polymorphisms in several folate-dependent genes involved with single-carbon metabolism. It is now recognised that some of these polymorphisms can significantly alter folate requirements among pregnant women. Another emerging area of interest that could influence the outcome of fortification is the composition of the gut microbiome. The size and diversity of the gut microbiome within specific populations can be influenced by an individual’s diet, which could, in turn, affect absorption of certain nutrients.
Even less is known and understood about the potential health impact of fortification with non- nutrient bioactive food components. Flavanols can serve as an example of a non-nutrient bioactive for which research has suggested health benefits. Numerous investigators have reported inverse associations between the consumption of flavonoid rich diets and the risk of cardiovascular disease, and there is evidence that one family of flavonoids (flavan-3-ols) is particularly of value with respect to vascular health. Complicating the issue of potential dietary recommendations for flavanols is the fact that the bioavailability and biological activities of the 4 flavan-3-ol isomers can show considerable variability. This is currently an issue because the flavanol content of most foods is not provided with respect to the specific isomers that are present. A further complication is that food processing can result in changes in the flavanol stereoisomers that are present in a food or beverage. For example, heating tea at a high temperature can alter the flavanol stereoisomer profile that is present in the final product.
3.10. Regulatory Monitoring of Food Fortification Programmes11, 17, 18
A key component of successful food fortification programmes is the regulatory monitoring.
Good regulatory monitoring and quality assurance and quality control (QA/QC) practices can help ensure that food products advertised as, or required by law to be, fortified are adequately fortified, meaning compliant with relevant regulations or fortified as claimed.
Regulatory monitoring of food fortification is the continuous collection and review of information at key delivery points to ensure fortified foods meet national standards. Regulatory monitoring encompasses:
Internal control, including QA/QC activities that are the responsibility of the food producer. The purpose of internal control is to identify and remedy irregularities throughout the production and packaging processes.
External monitoring, including inspections and audits that are the responsibility of government authorities. Legislation should provide the basis for external monitoring systems, including clear delineations of stakeholder roles and responsibilities and a prescription of enforcement tools to deter non-compliance. Governments use external monitoring to verify that manufacturing steps are properly implemented and result in a quality product. External monitoring by governments should complement, not replace, QA/QC processes and tests related to fortification at the production level.
3.10.1. Internal control
3.10.1.1. Quality assurance and control in food processing
The maintenance of a well functioning quality assurance (QA) programme is essential if a consistent product is to result that meets all required standards. Such a programme should be based on hazard analysis and quality analysis critical control point (HACCP and QACCP) systems. HACCP and QACCP are more proactive than traditional approaches to QA/QC activities. The establishment of such programmes is the responsibility of QA personnel but the execution of it involves everyone in the company. To avoid ambiguity regarding responsibility for any QA function, it is important to assign specific HACCP/QACCP accountabilities to responsible persons and groups.
A QA programme must consider all activities that have an impact on product safety and quality, from raw materials and ingredients used to product handling through distribution channels all the way to the final consumer. The components of a QA system include:
(a) Raw material control: Standard specifications must be adopted for all ingredients, which must then be inspected to ensure conformity.
(b) Process control: All chemical, physical and microbiological hazards as well as quality factors must be identified, critical control points (CCP) must be established, monitored, and a record made of any action taken.
(c) Finished product control: This requires that the finished product be unadulterated, properly labelled, and that the integrity of the finished product be protected from the environment.
3.10.1.2. Hazard analysis and quality analysis critical control point systems (HACCP and QACCP)
All food production activities must be monitored and controlled within the framework of an effective QA programme. The addition of nutrients to a food for the purpose of fortification increases the number of control points that must be considered. Poor manufacturing control leading to excessively high levels of nutrients in the finished product could have important health implications for the consumer if intake of the nutrient reaches the toxic dose.
Conversely, low levels of nutrients in the finished product could render it nutritionally ineffective. This could also have serious health implications if the target population in the fortification programme is at high nutritional risk. Poor manufacturing control could also lead to other quality defects related to interactions of added nutrients with other components of the system.
The following are the steps in the implementation of a quality assurance programme in the production of a fortified food:
(a) Product specifications: All specifications for fortificants, food vehicle and any other ingredients must be documented as well as acceptable deviations of these. These include specification of particle size, colour, potency, level of fortification as well as any other requirement that might be deemed necessary.
(b) Product safety assessment: This involves an assessment of microbiological, chemical and physical hazards for all ingredients and the finished product.
(c) Product analysis: Sampling and testing procedures for all ingredients and the finished product must be explicitly stated.
(d) Determination of critical and quality control points: Based on first hand knowledge of the total process (including the plant facility, equipment and environment) stages at which inadequate control could lead to unacceptable health risk or adversely affect product quality
are identified. The system of controls and actions to be taken at each control point are documented.
(e) Recall system: A mechanism must be put in place whereby product can be recalled if such action becomes necessary.
(f) QA audit: Periodic checks are necessary to verify that the QA system is effective and product quality is maintained up to the ultimate consumer.
(g) Feedback mechanism: Response to consumers and other relevant groups to correct any deficiencies discovered.
(h) Documentation of QA system: Details of the QA programme used in the production of the fortified food must be readily available to relevant individuals and organisations.
Shortcomings of many fortification programmes in the past have been due to failure to establish an adequate quality assurance programme. Evaluation of different fortification programmes emphasised the need for greater control in food fortification process.
HACCP is a management system in which food safety is addressed through the analysis and control of biological, chemical and physical hazards from raw material production, procurement and handling, to manufacturing, distribution and consumption of the finished product. It involves monitoring and controlling of materials and processes that could lead to a compromise in the safety of the final food products. HACCP is focused only on the health safety issues of a product and not the quality of the product, yet HACCP principles are the basis of most food quality and safety assurance systems.
QACCP was developed by relying on simple but well planned techniques to address both the quality as well as the safety of food products during processing. The HACCP/QACCP system therefore falls under quality assurance as well.
3.10.1.3. Analysis of vitamins and minerals
Analysis of potency of fortificants and of vitamin and mineral content constitute an important component of the overall analytical requirements in QA/QC programmes for fortification processes. Development or selection of appropriate analytical methodologies must be based on consideration of accuracy and precision of measurements, available facilities and equipment, simplicity of procedure and rapidity of determination.
For example, the determination of iodine content in iodised salt has traditionally been carried out using a titrimetric method. A number of HPLC (high performance liquid chromatography) based methods have also been used to a large extent. A differential pulse polarographic method that did not require a separation or preconcentration step can also be used. For qualitative testing in the field, simple test kits based on the reaction of starch with iodine are available.
In iron fortification programmes, quite often measurement of iron content is inadequate.
Bioavailability of the nutrients has been determined by measurement of labelled isotopes absorbed from the diet of human subjects or less complex methods based on animal studies such as the haemoglobin repletion method. There may be analyses other than the measurement of nutrient content or availability necessitated by a fortification programme. These might include the measurement of colour, particle size or moisture content as well as all testing required for the unfortified food. Based on the identification of critical and other control points, the analytical requirements of the overall quality assurance programme can be determined.
Laboratory analysis (or quantitative tests) plays an important role in regulatory monitoring, both internal and external. However, the results of laboratory analysis are subject to variation and do not provide conclusive evidence of compliance or non-compliance.
3.10.2. External monitoring
3.10.2.1. Role of food legislation and food control
Governments use external monitoring to verify that manufacturing steps are properly implemented and result in a quality product. External monitoring by governments should complement, not replace, QA/QC processes and tests related to fortification at the production level.
The primary purposes of food legislation are to protect the health of the consumer, to protect the consumer from fraud and to ensure the essential quality and wholesomeness of foods. In the case of fortified foods, there is a need to ensure that the population is not at risk of receiving toxic doses of any micronutrient. Food laws must also ensure that the target population does not receive nutritionally ineffective levels of micronutrients. Procedures for monitoring premises where fortified foods are prepared, packed, stored or held for sale as well as mechanisms for penalising defaulters must be clearly defined within the food regulations.
Standards for fortified foods and labelling requirements must also be contained within the food regulations. Standards play an important role in the facilitation of trade, both nationally and internationally. In light of the Agreement on Technical Barriers to Trade (TBT), the development of international standards for fortified foods is an important step in the elimination of technical barriers. Food law must first provide the legal authority and an adequate legal framework for the food-control activities. It has been found that food law is managed most effectively in two parts, i.e. a basic food act and food regulations. The act itself should set out broad principles while the regulations should contain the detailed provisions governing the different categories of products. The lists of approved fortificant compounds and food standards (stating the allowed levels of nutrients in the fortified foods) should be found within the regulations. Prompt revision of regulations may become necessary because of new scientific knowledge, changes in new processing technology or emergencies requiring quick action to protect the public health. With respect to regulations dealing with fortified foods, changes might be prompted as a result of safety evaluations on nutrient compounds or new information regarding the roles and optimal levels of specific micronutrients in the maintenance of good health. Changes in food processing and packaging technologies could be shown to result in a significant reduction in processing and storage losses of micronutrients, thus requiring a revision in the allowed levels of addition of nutrients. In the face of demonstrated micronutrient deficiencies, regulations regarding standards for certain foods and levels of fortification may need to be revised.
4. Summary
Micronutrient deficiencies are a major global health problem. It has long-ranging effects on health, learning ability and productivity. Micronutrient malnutrition leads to high social and public costs associated with reduced work capacity in populations due to high rates of illness and disability, and tragic loss of human potential.
Food fortification and enrichment are nutritional intervention programmes with a specifically defined target population. Its effectiveness is measured by whether or not the fortified food is accepted, purchased and consumed by that population. It is an important element in nutrition strategies to alleviate micronutrient deficiencies.
The success of food-fortification and enrichment programmes is measured by whether or not the nutrition and health status of the targeted population has been improved. The successful application of food fortification technology is based largely on consideration of the compatibility of vehicle, fortificant and process. Several important aspects should be carefully assessed in the development of such programmes, such as determining nutrient stability under normal conditions of storage and use. From the technical point of view, nutritional stability during formulation, preparation and processing is crucial for the effective production of fortified foods. Some strategies for stabilising nutrient content include the application of protective coating for the individual nutrient; the addition of antioxidants; the control of temperature, moisture, and pH; and protection from air, light, and incompatible metals during processing and storage.
It is not the appropriate tool in all situations and generally speaking, its use is required in combination with other techniques in order to obtain the optimal result. It is critical to identify all elements underlying any given nutritional problem. Food security, inadequate dietary diversity, lack of nutrition education and the state of food processing locally are among the factors which must be considered in determining the most appropriate strategy to be used and hence role to be played by fortification.
Adequate monitoring of food fortification is essential and should include both monitoring of critical control points in the production and distribution of fortified food and monitoring of the micronutrient status of target populations, in establishing the need for intervention and to assess the impact of food fortification. Food fortification must be controlled through the development of appropriate legislation. Adherence to the legislation will ensure that the objectives of the food fortification programme are achieved and that the levels of micronutrients are controlled within safe and acceptable limits.
The identification and development of fortifying agents that will guarantee product quality and high bioavailability are technological and scientific challenges. Some options for the future are the microencapsulation of nutrients, the use of nutrient bioavailability stimulants (addition of ascorbic or other organic acids to promote iron absorption), and the elimination of inhibitors of mineral absorption in the intestine (e.g., phytates). Food fortification will continue to be an important tool, not only to treat or prevent specific nutritional deficiencies, but also to promote a general state of well-being in different populations, and possibly to prevent certain chronic diseases.
5. References
1. World Health Organization. Preventing and controlling micronutrient deficiencies in populations affected by an emergency. Joint Statement by the World Health Organization, the World Food Programme and the United Nations Children’s Fund. Geneva, Switzerland: World Health Organization, 2007. Available at:
http://www.who.int/nutrition/publications/WHO_WFP_UNICEFstatement.pdf. Accessed October 25, 2016.
2. Wimalawansa, Sunil J. Rational food fortification programs to alleviate micronutrient deficiencies. Journal of Food Processing & Technology 4, no. 8 (2013): 257. doi:
10.4172/2157-7110.1000257. Available at: http://www.omicsonline.org/rational-food- fortification-programs-to-alleviate-micronutrient-deficiencies-2157-7110.1000257.pdf.
Accessed October 25, 2016.
