Studies on Storage of Dried Japanese Noodle

Part I. Relation between NaCl content of dried noodle(udon)and its equilibrium moisture

Abstract

In the manufacturing process of dried Japanese noodle(udon), salt is added for the prevention of cracks on noodle. Relation between NaCl content and equilibrium moisture was hereby examined. Moisture contents of many dried Japanese noodles by JAS inspection were also investigated. The results obtained were as follows:
1. Water sorption isotherm of dried udon was remarkably influenced by added NaCl in atmosphere having high relative humidity over 60%. Equilibrium moisture of dried udons containing 5.39% NaCl(dry basis)was 6% higher than that of non-added NaCl udon at 86% relative humidity.
2. As for teperature, equilibrium moisture of dried udon at 30°C was 0.6-0.8% lower than thatof 20°C.
3. Equilibrium moisture of dried udon was approximately 1% lower than that of original flour itself in case of non-added NaCl.
4. Moisture contents of dried Japanese noodle showed considerably lower mean value than the inspection standard. Mean values of several noodles were:
Hiramen, 12.92%; udon, 12.79%; hiyamugi, 11.74%; and somen, 11.46%.