Soybased Functional Foods with Reference to Probiotics and Isoflavones

Multifold benefits of soybean as healthy functional food for human reveals that, it
contains more protein than beef, more calcium than milk, more lecithin than egg with
more vitamins, minerals and many biologically active components. Soybean is cheap,
conventional, convenient and richest source of protein for the fast expanding population.
Efforts have been made to bring out different delicious novel foods from soybean to
promote its wide consumption and acceptance.
Among the non fermented soyfood, tofu is popular for its protein content. It is
usually coagulated with synthetic coagulants. It gets contaminated easily. Little
information is available on the microbial quality of tofu. Likewise effect of various
natural coagulants of plant origin on the amount of isoflavones and antioxidant activity of
tofu is still unknown.
Soymilk fermented with lactic cultures and the bioconversion of isoflavones is
extensively studied. However, there are only few studies with combination of yeast,
stability of these cultures in fermented soymilk and survival of food borne pathogens like
Staphlococcus aureus and Listeria monocytogenes in soymilk.
This thesis describes studies on soybean for use as food, microbiological quality
of tofu and influence of coagulants of plant origin on the isoflavone content of tofu. It
also explains the fermentation of soymilk with probiotic lactic acid bacteria with
combination of probiotic yeast Saccharomyces boulardii. It elucidates the partial
characterization of the antimicrobial compound and utilization of by-products of tofu
preparation in Indian traditional foods, specifically taking into account its functional and
nutritional values.