Hydrolyzed okara in low-fat pork burgers under pilot scale

Okara (soybean curd refuse) is the major byproduct in the manufacture of soymilk and tofu. Okara cannot be used in foods due to its high moisture and poor mouth feel. Relatively high insoluble dietary fibers are the main reason for the poor sensory quality. In this study we used the Viscozyme (TM) and Pectinex (TM) to degrade the first and second layers of soybean cell wall and transform okara as an ingredient for meat products. Pork burgers incorporated with six different levels of hydrolyzed wet okara (5, 10, 15, 20, 25 and 30%) were prepared and compared with controls (without okara). Cook loss (%), cholesterol content, water holding capacity (WHC), color attributes and sensory evaluation were conducted to evaluate the feasibility of hydrolyzed okara as meat product ingredient. While the moisture contents of raw and cooked pork burger increased with the addition of various percentage okara, the addition of okara reduced the cholesterol content by about 6 similar to 56% for raw pork burger and 14 similar to 47% for cooked burger. The WHC and cook loss (%) of pork burger were improved by the addition of okara. The addition of okara also increased the pH, L* and, b* values of raw pork burger but did not affect a* value. Significant effects of okara on overall acceptability were observed when the addition of okara was above 25%.