PENGARUH KONSENTRASI ASAM SITRAT DAN LAMA PERENDAMAN TERHADAP DERAJAT PUTIH DAN KUALITAS KIMIA TEPUNG JEWAWUT

Abstract

This study aimed to evaluate the effects of citric acid concentration and soaking duration on the physicochemical properties of millet flour, particularly its color characteristics and browning inhibition efficiency, and to determine the optimal soaking conditions for producing high-quality millet flour. The evaluated parameters included whiteness degree, color attributes (L*, a*, and b*), moisture content, ash content, and pH. Whiteness degree and color were measured using colorimetric methods, while moisture and ash contents were determined using thermogravimetric methods, and pH was measured using a digital pH meter. The experiment consisted of four citric acid concentrations (0%, 1.5%, 2.0%, and 2.5%) and two soaking durations (45 and 60 minutes). The results showed that citric acid soaking effectively inhibited browning and improved the color quality of millet flour. Increasing citric acid concentration generally increased lightness (L*) while reducing the intensity of undesirable browning. The optimal treatment was achieved at a citric acid concentration of 1.5–2.0% and a soaking duration of 45 minutes, which yielding flour with improved color quality and favorable physicochemical characteristics. At 1.5% citric acid, browning inhibition was initiated effectively, whereas 2.0% citric acid provided the best balance between color improvement and flour structural stability. Therefore, citric acid soaking can be considered an effective pre-treatment for enhancing the quality of millet flour.