By: Debomitra Dey *
Soybean has been an important ingredient of the human diet since the 18th century. This legume-based crop has been utilised for numerous value-added products such as; texturised vegetable product (meat analogues); soy milk; soy sauce; miso; tofu; and infant formula. Soybean is one of the touted functional foods in today’s time due to its nutritional composition which consists of about 60 percent of protein and oil content along with a good balance of dietary fibres, carbohydrates, vitamins, and flavonoids. Due to the high protein content soybean is a complete source of protein, which consists of a significant amount of essential amino acids.
It is believed that soybean has many health benefits including the prevention of breast cancer, prostate cancer, heart diseases, and osteoporosis. The health benefits of soybean are attributed to the functional properties of soybean which include; high fibre content; high protein content; essential amino acids; antioxidants; and phytoestrogens. Researchers have reported that phytoestrogens play a critical role in cancer prevention. Soybeans contain a high amount of isoflavones and have been found to be protective against breast cancer and prostate cancer. The nutritional composition of soybean is depicted in the given table.
Soybean as Meat and Dairy Substitute
Soybean can essentially replace meat and dairy due to its high protein content. The biological value of soybean is 74 and its counterpart cow milk, whole egg and beef are 91, 100 and 80 respectively. Soybean-based products are highly accepted by vegan and lactose-intolerant consumers. The growing demand for meat and dairy alternatives has increased the market and opportunities for food producers to plunge into plant-based meats and non-dairy products.
Meat analogues as texturised vegetable products (TVP) have been in the market since the past 50 years. These soybean products are texturised to give an appearance similar to meat. These products are fortified using essential minerals, vitamins, and meaty flavour to enable producers to create plant-based meats. TVP have replaced ground beef, and offer similar texture and nutritional profile for vegan and vegetarian consumers. The main challenge here for food producers is to optimise the flavour and nutritional profiles of soybean chunks to meet the expectations of the consumers. Currently, the market provides a range of soybean-based meat products such as gluten-free vegan meat, plant-based meat burgers, and texturised vegetable products.
Now coming to soybean’s role as a dairy substitute, soymilk has been a traditional drink in Asia since times immemorial. Soymilk is commercially available in the market from the 1940s. Soymilk is prepared by soaking, grinding soybeans and heating them to remove the beany flavour of soybean. Raw soybean milk serves as the base of soy-based products such as; tofu; cheese; and yoghurt. Another product of interest is tofu; this is highly consumed by consumers worldwide. The base for tofu preparation is soymilk which is then coagulated and curdled to form the final product. Tofu is high in protein and calcium and it has been a staple food of Asians for over a hundred years. The taste and texture of tofu vary with consumers around the world. E.g. in America consumers prefer tofu with its bland taste, whereas in Asia it is preferred because it has beany flavour.
Soybean-based Fermented Products
Fermented soy-based products accepted by consumers all around the world which include; soy sauce; miso; tempeh; and fermented natto. Other fermented foods such as; stinky tofu; chungkookjang; and fermented bean curd are not well-accepted by the consumers due to the flavour and mouth-feel of these products.
Soy sauce and miso are flavouring agents which are used in cooking and have similar aroma and flavour. Soy sauce is in liquid form and miso is a paste. Products like soy sauce have gained global acceptance due to the frequent usage in preparation of dishes. Soy sauce is prepared by a two-step fermentation process by addition of Aspergillus oryzae, Aspergillus sojae it is a savoury seasoning widely used in Asian and American cuisines. The flavour, colour and aroma during the fermentation of soy sauce are due to Maillard browning reactions. Soy sauces are used in food industry as a flavour enhancer and a colouring agent in a variety of processed foods.
Soy-based Infant Formula
Soybean-based infant formula is used for infants who are not breastfed and/or allergic to cow milk proteins. In 1990 researchers have used a tempeh-based infant formula for children under the age of five years to overcome diarrhoea due to consumption of pasteurised milk. These infant formulas are sold in the powdered form, ready-to-eat and concentrated liquid form.
Due to the growing awareness and research of soybean, the demand for soy-based products has increased in the past decade. The consumers understand the nutritional value and health benefits of consuming soy-based products hence, food processors and researchers are working on developing novel soy foods for the future. The future of meat will certainly change due to the change in a scenario in the food ecosystem, wherein plant-based meat are developed using soybean flour. The meat analogues are crafted to match the texture and the umami flavour of the meat. Soybean is also believed to have functional properties beneficial for the protection of cancer. These attributes of soybean have certainly increased the face value of the crop and would lead to developing utilisation of soybean beyond its application as oil, but also receive attention for designing foods for the future!
* Source: Founder at the Food Tech Club