Good health comes from good diet, this is a well recognized fact by the consumers. Lipids are important components of human diet, hence they have significant benefits for consumers and food industry. Seed oil is one of the important parts of human diet due to the presence of important essential oils, tocopherols and phytosterols. Chia seeds, flaxseed and sunflower seeds have attracted the attention of nutritionists and due to the presence of various components such as dietary fiber, protein, vitamins, omega-3 fatty acids, antioxidants, phenolic compounds and indispensable nutrients these are emerging as plant-derived nutraceuticals and recognized as important functional foods, which are used to make products in the form of seeds and oils to supplement the food items with linolenic acid. This review mainly provides information about the role of various seeds in food industry, their health benefits and industrial applications.
Introduction
Food security occurs when the entire population gets proper, safe and nutritious food that fulfills their dietary requirements and food desires for vigorous growth, well-maintained physical, community and economic lifespan. Currently, the need for healthy living is increasing the search for functional foods and nutritious foods that are associated with good vigor. Food industry companies are in greater need of food products that can fulfill the need of consumers for a vigorous life. In this context, functional food appears as an important asset that not only reduces malnutrition and provides essential nutrients but also enhances consumers' physical and mental health and prevents nutrition-related diseases and these foods also appear as resourceful and promising assets to deliver fitness benefits.
Salvia hispanica L. often acknowledged as chia, is an annual oilseed herbaceous crop, belonging to the Lamiaceae family, native to Mexico and northern Guatemala. Chia seeds have recently been recognized as an essential part of the human diet and are progressively consumed worldwide due to their nutritional composition and are considered a beneficial agricultural crop. Chia seeds are used as a dietary supplement and there are continuous efforts by researchers to promote it as a functional food due to the presence of alpha linolenic acid in it.
Linum usitatissimum commonly called flaxseed is a prehistoric essential global annual herbaceous seed crop belonging to the Linaceae family. People have been consuming flaxseed worldwide since the early period of ancient civilizations. Flaxseed is widely used in functional foods and is taken as a dietary supplement or as an additive to make food products because of its exceptionally high content nutritional composition i.e. β-linolenic acid, dietary fiber, protein, phytoestrogens and due to its beneficial pharmaceutical value. Helianthus annuus commonly known as sunflower belongs to the Asteraceae family, it is a profitable agricultural crop and its seed oil is one of the most widely used essential oils worldwide.
Various seeds used in food industry
Chia Seeds: Chia seeds have great impact on the people who take it in diet routine and are recognized as super nutritional foods. Chia is a major oilseed crop containing high amount of -3 fatty acids, gluten free protein, dietary fiber, vitamins (vitamin B1, B2, B3, B9, vitamin C and vitamin A), minerals (calcium, phosphorus, potassium and magnesium), wide range of polyphenolic compounds i.e. chlorogenic acid, protocatechuic acid, gallic and p-coumaric acid, quercetin, caffeic acid, rutin, apigenin, kaempferol, myricetin and antioxidants. The proportion of protein, fat, carbohydrate and dietary fiber in chia seeds ranged from 15 to 25%, 30–33%, 41%, 18–30%, respectively.
Chia seeds have been recognized as a new food by the European legislature, which has led to its increased use in various foods and also has therapeutic properties by producing a high amount of essential oil, which is used for the manufacture of -3 capsules. Chia seeds are also consumed whole, powdered and in the form of gel and oil and as a substitute for eggs and fats due to the hydrophilic nature of the seeds. A 25% level of replacement of oil or eggs in cakes by chia seed gel has beneficial effects on the sensory aspects of the product, for example color, taste and texture but at 50–75% level of oil replacement in breads, adverse changes in the concentration and inclusive superiority of baked foods were found. Chia seed flour also appeared as an excipient for preparing pasta in place of wheat flour and they evaluated that pasta made with a proportion of chia flour had higher nutritive value than pasta prepared with wheat flour alone due to the presence of higher levels of protein, nutrients and dietary fiber and also found that pasta with 7.5% level of chia flour displayed commendable nutritional properties and accepted as having maximum acceptance index in terms of taste.
Gruel prepared from chia seeds is also used for manufacturing ice cream as an alternative to emulsifiers and stabilizers. Gluten-free, -3 and fiber-rich chips are made from chia flour when taken in different proportions i.e. 5%, 10%, 12% and 15% and found that chips made with 5% of the flour had maximum consumer acceptability. Chips made with 5% flour showed no deviation in taste, colour, aroma, texture and overall flavour of the product as compared to commercially prepared chips. Chia mucilage can also be used to prepare bread and chocolate cakes, which can remove up to half the proportion of fat without changing the overall characteristics of the product and this chia mucilage is a new alternative to replace fat from foods and is useful for maintaining the overall nutritional and quality characteristics of food products. Recently, the use of chia seeds has also increased in milk items like yogurt and ice cream.
Flaxseed: Currently, flax seeds are attracting the attention of scientific and medical journals due to the presence of many medicinally and biologically important active components, hence it is called the quintessential functional food and recognized as a functional food due to the presence of three important active components i.e. -linolenic acid, lignans and dietary fiber. Flaxseed contains high amount of polyunsaturated omega 3 and 6 fatty acids, mucilage, polyphenolic compounds, natural waxes, vitamins (A, B, E), minerals, squalene, proteins, lignans, oil and soluble fiber. The processing of flaxseed for manufacturing various industrial products, not only makes it an important crop for humanity but is also recognized as a bio-economy crop of the recent decade. The growing demand for flaxseed as a functional food has led to an increase in consumer requirements for food additives and due to the low -6/-3 ratio of flaxseed, it is considered a functional food and nutraceutical.
Recently, it is used in making cakes, multigrain breads, organic products, salad dressings, soups, biscuits, crackers and ready-to-eat breakfast cereals and beverages and it is also used in dairy products, yogurt and bread toppings and is also commercialized as a soft-gel capsule as a dietary supplement. Flaxseed is added as a fortified ingredient in bakery products and some dietary products. In the United States, its flour is used industrially to make bread. In Ethiopia, its seeds are typically cooked, pulverized, mixed with spices and H2O, served with injera and bread, used to prepare meals, edible oil and also taken as porridge and a beverage called chilika. Flaxseed flour is gluten free and its protein content as well as the gelling or binding properties of its soluble fiber are used to make gluten free baked products or thickening agents and it is also used as an excipient to prepare baked foods instead of eggs.
Sunflower seeds: Helianthus annuus L. is a useful oilseed crop cultivated worldwide and has various medicinal properties that make it a nutritious food and medicine globally. Sunflower seeds contain high amounts of mineral nutrients, antioxidants, vitamins, unsaturated fats, protein, dietary fiber, selenium, folate and various phytochemicals. Sunflower seed oil has moderate taste, light color and high oxidative persistence, hence it is recognized as a quality oil used to make many food products and these products have high nutritional value due to seed processing technology. Sunflower cake contains large amount of crude protein and ether extracts which remain after oil extraction. When sunflower cake (10 and 20%) is used to make chapatis and biscuits, the amount of protein, fat and fiber values increase significantly. The inclusion of sunflower seeds in varying quantities in bread enhances the taste, flavour and overall nutrient content of bread and can replace up to 16% of wheat flour. Sunflower seed oil is sold for retail sale and household consumption, for example, in industry, it is extensively used for frying (snack foods), encapsulation of volatile oils and flavour compounds, manufacture of emulsions, sauces and margarines and as an appreciable flavour carrier.
Conclusion
Functional foods are one of the most important, promising and rapidly growing aspects of the food industry. Various applications in the food industry have led to an increase in consumer demand for oilseeds (chia, flaxseed and sunflower seeds) in the form of food products such as bread, cakes, cookies, cereal bars, etc. which provide health benefits. The nutritional aspects of these seeds can be improved to increase their consumption in the daily diet of both international commodities and rural populations. Due to the presence of many beneficial nutrients in chia, flaxseed and sunflower seeds, their cultivation in agriculture and around the world should be improved. It is proposed to grow these oilseed commodities as staple food grains to save the population from starvation.
