Functional Foods

Functional foods include a huge range of foods like whole foods along with fortified, enriched or enhanced foods, probiotics and designer foods. Functional food has been categorized as conventional foods, modified foods and functional food ingredients. Another way of classification suggest that functional foods are 1st, 2nd and 3rd generation foods which includes supplements, whole foods and novel foods respectively.

Conventional foods: Whole foods that are naturally occurring and possess beneficial effect on human physiological conditions are categorized in conventional foods. E.g. Whole fruits, vegetables, grains, nuts, seeds, legumes, dairy, meats, and sea foods. Such foods contain an abundant amount of numerous bioactive compounds inherently and have been associated with good health.

Probiotics are the selective, viable microbial cell administered in adequate amount to provide numerous health promoting benefits along with basic nutrition [13]. These viable microbial dietary supplements exhibit beneficially affects in the host through its effects in the intestinal tract”. On the other hand, functional food term is used to describe nutrients that have positive effects on physiological processes beyond the traditional nutritional effect. Probiotics could enhance physiologic functions benefiting health or preventing disease and be classified as functional food ingredients [14]. It is a novel concept and good health can be achieved by nurturing the body’s naturally occurring microorganisms and ensuring the proper functioning of the digestive tract. Lactobacillus, Bifidum and Leuconostoc bacteria present in the human intestine modulate gut microbial load, prevent the flourishing of unfavorable intestinal pathogens and thus improves the microbial status of intestine [15]. The common probiotic foods are fermented milk and yoghurts present in market eg Yakult in Japan, Suntory Bikkle in Japan, Actimeal in Paris, Vifit in Netherlands, Nestle LC1 in Switzerland, and Nesvita in Switzerland. But in last few years, trend has shifted to nondairy probiotics also eg. Fermented vegetables, fruits, meats, grains, olives as large number of people are suffering from lactose intolerance and cholesterol level [16].

Modified Foods: Such foods have been modified through different ways viz., fortification, enrichment, growing practices, enzymatic, genetic, mechanical to meet the desired requirement of consumers. Food fortified with additional nutrients like minerals and vitamins in order to prevent disease are fortified foods e.g. Fruit juices fortified with Vitamin C; calcium fortified bread, ω-3 fortified breads, or phytosterol fortified spreads, vitamin D fortified milk, folic acid fortified flour and cereal products, iodine fortified salts. All these essential nutrients are added to cope up with mass health issue and are distributed under public health initiative [17].

Enriched products are the foods with added new nutrients or components that are not normally found in a particular food. e.g. Vitamin A and D addition to margarine, herb incorporated energy drinks [18]. The foods in which some functional components have been enhanced through special practices like genetic modification, agricultural practices, modified nutrient supply or postharvest treatments are categorized in enhanced foods e.g. omega-3- rich eggs by modifying chicken feed beef with high conjugated linoleic acid, functional grapes with higher antioxidant activity developed through ultraviolet irradiation, iron rich/thiamine rich rice, better healthy fatty acid composition in vegetable oils, allergen free foods, carotenoids rich canola oil, and lutein rich wheat etc.

Different types of functional foods have been launched in different categories e.g. bakery, confectionery, dairy, probiotics, meat, baby foods etc. [19].

Milk is a nearly complete food with good amount of proteins, fat, minerals. Dairy products contain various biologically active compounds like bioactive peptides, antioxidants, vitamins, lactoferrin, immunoglobulins, oligosaccharides, conjugated linoleic acid, organic acids, melatonin etc. These bioactive compounds have been associated with lots of bioactivities e.g. haemodynamics, modulating digestive and gastrointestinal functions, favoring and maintenance of intestinal microflora etc. [20]. Different examples of functional foods commercially available are ‘Calpis’ sour milk with functional ingredients for lowering the blood pressure developed by Calpis Co. (Japan); ‘BioZate’ hydrolysed whey protein isolate containing β-lactoglobulin fragments for regulating blood pressure and ‘BioPure-GMP’ whey protein isolate containing glycomacropeptide as functional ingredient for regulating blood pressure, dental issues, viral and bacterial infections were developed by Davisco (USA); protein hydrolysates named ‘C12’ and ‘Cysteine peptide’ with functionality of lowering the blood pressure and maintaining high energy level respectively developed by DMV International (The Netherlands); ‘Clarinol’ yoghurt formulation with conjugated linolenic acid to reduce body weight (Lipid Nutrition, USA). Dairy products like drinks, yoghurts and spreads are suitable carrier for functional food formulation. Major section of functional foods is occupied by dairy products and is expected to increase at compound annual growth rate (CAGR) of about 8% in coming years [21].

Cereal grains are grown all over world due to their adaptations to wide range of environmental conditions and are the staple food across the globe [22, 23]. Different cereals consumed are wheat, rice, maize, sorghum, barley, millets possess numerous macro, micronutrients and bioactive compounds accounting for numerous health benefits [24]. Different bioactive compounds present in cereals viz., tannins, phytates, phenolics, flavonoids, carotenoids, anthocyanins, phytosterols and fibers etc. have been associated with lowering cholesterol level, oxidative stress, prevent cardiovascular disease, diabetes, obesity and cancer etc. This clearly indicates about their potential for usage as functional food ingredient [25]. The fibers like β- glucan, arabinoxylans and oligosaccharides like galacto- and fructo- oligosaccharides and resistant starch stimulates and maintains the growth of intestinal microflora and also act as prebiot-ics [13]. The immature kernels of grains contain higher amount of lysine, fructans, and simple sugars and thus appropriate to be used in functional foods [26]. The extraction and purification of such biologically active ingredients can be attained by knowledge of their distribution pattern in grain and concentration at different maturity levels and advanced processing technologies. β-glucan is a valuable dietary fiber present in barley and oats, accounting for reducing the cholesterol level and glycemic index. Extracted β-glucan have been incorporated in various products like breakfast cereals, baked products, pasta, chews, nutrition bars, yoghurt, ice-cream, beverages and dietary supplements. The different industries like Cargill, Kerry Group, Angel Yeast Co. Ltd., Agroingredients Technology, Super beta glucan, Immuno medic, DSM, Ohly, Tate & Lyle PLC, Frutarom, Sigma Aldrich Corporation, Alltech Life Sciences, Parrheim Inc., Lesaffre International, Biorigin, Nutraceuticals Inc., Speciality Biotech, Ceapro Inc., and GlycaNova are the leading key player industries for beta glucan.

Resistant starch is defined as starch which is resistant to digestion in small intestine and passes to the large intestine and is fermented by intestinal colon microflora. Resistant starch fermentation produces short chain fatty acids, acetates, propionates and butyrates [27]. Resistant starch can be incorporated in wide range of food due to their water solubility and indigestibility without any impact on sensory profile of food. This will provide bulk to food sample without contributing calories. The prolonged consumption of resistant starch may decline the fasting cholesterol and triglycerides and increases the absorption of micronutrients [28]. Lopez et al ., [29] reported the improved absorption of minerals (calcium, magnesium, iron, zinc and copper) in intestines of rats when fed on a resistant starch rich diet.