Studies on Noodles

Part VIII. Influence of hydrogen peroxide on components of Japanese noodle

Abstract

Hydrogen peroxide (H₂O₂) has been used for the purpose of sterilization of noodle in Japan, and the maximum amount of residual H₂O₂ permitted by the Food Sanitation Law is under 100ppm in Japanese noodle (udon). In this paper, the influence of H₂O₂ on loss of food additives in noodle and on some proteins (gluten and concentrated protein from rye or foxtail millet flour which were the materials reacting to reduce H₂O₂) were studied. Glycine and lysine were not decomposed by H₂O₂. Thiamine hydrochloride and dibenzoyl thiamine were decomposed in according to the additional amount of H₂O₂. By the treatments of steaming (100°C, 15min.) and storage (37°C, 7 days) of 20g of noodle-paste, additional glycine (1.1%) and H₂O₂ (850ppm) induced 2.3ppm of folmaldehyde. The oxidation of the proteins above-mentioned by H₂O₂ might be considered to be negligible, because the amount of oxygen-gas evoluted by the reaction of these proteins with H₂O₂ was equal to the calculated amount from the H₂O₂ decomposed by each protein. Composition of amino acids of proteins in noodle, which was stored for 3 days at 37°C after addition of H₂O₂ (0-850ppm) and steaming (100°C, 15min.), was analyzed by an automatic amino acid analyzer. The treatment of H₂O₂ gave almost no influence on the composition of amino acids.