PREPARATION OF AN IMITATION SOY SAUCE FROM HYDROLYZED DRIED YEAST CANDIDA UTILIS

Abstract

Acid hydrolysis of dried fodder's yeast Candida utilis was studied by a central composite design taking into account three independent variables: temperature (105-165C), processing time (30-70 min) and HCI concentration (7.5-17.5%). Response variables were: color, dry matter solubilization and amino nitrogen. Temperature was the most significant variable followed by acid concentration and processing time. Response surfaces were generated from fitted polynomials. Higher temperatures to prevent amino nitrogen degradation were not investigated. As different effects were found for color development and amino nitrogen, a combined function was tested which yields the behavior of all responses simultaneously. The best conditions were: 150C, 15% HCl and 40 min. After neutralization with 6N NaOH and centrifugation, the raw sauce was supplemented with 12% NaCl, 0.1% monosodium glutamate, 2% vinegar and 0.1% sodium benzoate and evaluated by sensory analysis for eight distinct attributes. Imitation sauce from yeast was at least as good as commercial hydrolyzed soybean sauce.