Efficacy of pectin and insoluble fiber extracted from soy hulls as a functional non-meat ingredient

The objectives of this study were to evaluate various chemical extraction methods of soy hulls for pectin and insoluble fiber and to determine the impacts of these fibers on physico-chemical and textural properties of meat emulsion systems. Crude soy hulls (CSH), lime treated soy hulls (LSH), acid and lime treated soy hulls (ALSH), and soy hull pectin (SHP) were extracted through various successive acid and lime treatments and incorporated in pork emulsion systems. Chemical extraction increased the redness, yellowness, acid detergent fiber (ADF) and ash content of soy hulls. Similar hydration properties were observed for CSH, LSH, and ALSH. In meat emulsions, LSH and ALSH influenced positive effects on reduction in cooking loss and increase in hardness without any adverse effect on springiness and cohesiveness (P < 0.05), and minimized color alteration. SHP resulted in a significant decrease in cooking loss and an increase in hardness. These positive effects of LSH and ALSH might be associated with the increase in ADF content and dispersibility based on observed microstructure images. Our results suggested that both pectin and insoluble fiber from soy hulls through acid and alkali hydrolysis could be used as novel functional non-meat ingredients.