Okara–by-product from soy processing: characteristic, properties, benefits, and potential perspectives for industry
Abstract
A by-product from processing of soy into drinks and tofu is the insoluble portion of soybeans, a high-fiber product called okara. With the growing interest in plant substitutes for meat and milk, which are produced mainly from soy, the amount of this by-product, which is often considered waste, is also increasing. Its processing then causes considerable financial and environmental problems. In addition to fiber, okara is rich in proteins, fats, micronutrients, and various phytochemicals. However, these are often in an unavailable form and, in addition, due to okara's high water content, it is easily perishable. Therefore, this review article aimed to gather information on the nutritional composition of the okara, possible adjustments to make unavailable nutrients available, and stabilization at the end of its new incorporation into the food chain either in the capacity of soil amendments and fertilizer to improve food quality and size or directly as a food ingredient.
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