Effects of Various Concentrations of NaCl in Boiling Water on the Hardness of Spaghetti

Abstract

The effects of various concentrations of NaCl (₀%, ₀.₂%, ₁%, and ₂%) in boiling water on the hardness of spaghetti were investigated. For all test samples, the breaking stress of the boiled spaghetti tended to increase when the boiling water contained ₂% NaCl, suggesting that the addition of ₂% NaCl resulted in harder spaghetti. The water content of the boiled spaghetti decreased upon boiling in water containing ₂% NaCl. Spaghetti dye experiments also indicated that the addition of ₂% NaCl reduced the moisture absorption of spaghetti, thus contributing to its hardness. Furthermore, gluten was also boiled in water containing NaCl. The water content of gluten decreased significantly upon boiling in water containing ₂₀% NaCl. However, no significant difference was observed with the samples boiled in water containing less than ₂% NaCl. Therefore, constituent components, other than gluten, may have contributed to the hardness of spaghetti boiled in water containing ₂% NaCl.