Effect of Ultrasonication on the Yield, Texture and Nutritional Content of Tofu Made from Green Peas (Pisum sativum).

Abstract

Soybeans (Glycine max (L.) Merr.) are the primary raw material in tofu production; however, Indonesia’s heavy dependence on imported soybeans raises concerns about sustainability and food security. Green peas (Pisum sativum), which are locally available but underutilized, offer potential as an alternative protein source. This research aimed to optimize an energy-based ultrasonication treatment of green pea slurry to enhance tofu quality, particularly in terms of yield, texture, and nutritional composition. Ultrasonication was applied using combinations of amplitude levels (30%, 60%, and 90%) and treatment times (5, 10, and 15 minutes) prior to coagulation with magnesium chloride (MgCl2). These two parameters were combined into a single fundamental variable, ultrasonication energy (kJ). This energy-based analysis allowed all treatments to be mapped within a unified totalenergy framework to identify the optimum processing condition. The results revealed that ultrasonication energy significantly modified the protein matrix, as reflected by the inverted parabolic relationship between energy and yield, texture attributes, and most nutritional parameters. The optimum condition was achieved at approximately 162 kJ, which produced tofu with the highest yield representing a 78.38% increase compared with the non-sonicated control. These findings demonstrate that green pea-based tofu processed under optimum ultrasonication energy conditions shows strong potential as a promising alternative raw material for high-protein tofu production in Indonesia.