Production of a high-protein meal and fermentable sugars from defatted soybean meal, a co-product of the soybean oil industry

Oilseed meals into foods: an approach for the valorization of oilseed by-products

The excellent health benefits of oil extracted from seeds have increased its application in foods, pharmaceutical and cosmetic industries. This trend leads to a growing research area on their by-products, oilseed meals, to minimize environmental and economic issues. Examples of these by-products are soybean, peanut, kenaf seed, hemp, sesame, and chia seed meals. It is well known that soybean meals have wide applications in food and non-food industries, while other seed meals are not well established. Most oilseed meals are rich in health beneficial compounds and are potential sources of plant protein, dietary fiber, and antioxidants. Many studies have reported on the valorization of these by-products into value-added food products such as bakery and meat products to increase their nutritional and functional properties. These efforts contribute to the sustainability, development of novel functional food and support the zero-waste concept for the environment. This review aims to provide information on the composition of selected oilseed meals from soybean, peanut, hemp, kenaf, sesame and chia seeds, their potential applications in the bakery, meat, beverage, pasta, and other food products, and to highlight the issues and challenges associated with the utilization of oilseed meals into various food products.

Development of Defatted Soy Flour-Based Adhesives by Acid Hydrolysis of Carbohydrates

Soy-based adhesives are attracting increasing attention in recent years because they are a renewable and environmentally friendly raw material. Defatted soy flour (DSF), comprised of 50% protein and 40% carbohydrate, is the most widely used raw material for the preparation of soy-based adhesives that are unfortunately hampered by poor gluability and water resistance. In the present study, we developed a self-crosslinking approach to prepare a formaldehyde-free defatted soy flour-based adhesive (SBA). Carbohydrates in the DSF were hydrolyzed with 0% (controls), 0.5%, 1.0%, 2.0%, 3.0% and 5.0% hydrochloric acid, and cross-linked with proteins to prepare the SBA. The effect of hydrolyzed carbohydrates on the performance of the SBA was investigated, and hydrolyzed carbohydrates significantly increased the amount of reducing sugars, but decreased insoluble substances. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses revealed an enhanced cross-linking structure with fewer hydrophilic groups in cured SBAs. Maillard reactions between hydrolyzed carbohydrates and proteins resulted in SBAs with better gluability, rheological properties and thermal stability than controls. Scanning electron microscopy (SEM) images showed that plywood bonded with SBA had a higher wood failure rate than controls. This approach has potential for preparing bio-adhesives with enhanced properties from other natural resources with a similar polysaccharides and protein composition.