Nutritional composition of tauco as Indonesian fermented soybean paste

Abstract

Tauco is a fermented soybean paste like miso but typical from Indonesia, commonly used as umami seasoning. This study objective was to evaluate the nutritional composition of diverse tauco products found in Indonesia and to determine a potential tauco product characterized by certain amino acids related to umami peptides (Asp, Glu, Gly, Ser, Thr, Val). Proximate composition, NaCl salt, total sugars, total acids, and total amino acid profiles of 24 tauco products, collected from 24 producers in 7 provinces in Indonesia, were analyzed. The proximate composition mapped tauco into solid (containing 29.2–35.3% moisture on wet weight basis or ww), semisolid (42.2–54.5% ww moisture), and liquid (56.2–68.1% ww moisture). Solid tauco composed of 54.7–65.2% carbohydrates, 10.0–22.8% ashes, 7.13–16.9% NaCl salt, 9.72–11.9% crude proteins, 11.9–27.0% total sugars, 6.98–23.4% crude fats, 1.24–2.18% total acids, and 11.4–17.5% total amino acids on dry weight basis (dw). In contrast, liquid tauco consisted of 8.47–56.5% dw carbohydrates, 17.1–73.8% dw ashes, 10.7–68.4% dw NaCl, 20.4–30.9% dw crude proteins, 4.45–29.9.5% dw total sugars, 1.30–18.9% dw crude fats, 1.65–5.36% dw total acids, and 14.1–24.6% dw total amino acids. All tauco had a slight acidic pH, ranged from 4.38 to 5.91. Glu and Asp were the dominant amino acids of tauco, comprising 25–40% of total amino acids. Mapping of total amino acid profile mentioned a tauco product, characterized by the highest concentration of amino acids related to umami peptides. This finding leads to the exploration of umami peptides to reveal the science behind its traditional use as umami seasoning.