Abstract
The quality of 124 samples of “Ita-Konnyaku”(Block Type Konnyaku)obtained commercially in 7 districts of eastern and western regions of Japan were compared in terms of physical properties, pH and contents of solid matter, konnyaku mannan (KM) and minerals to clarffy the regional differences.
1) The shearing strength of heated konnyaku is significantly larger in konnyaku of western Japan than that of easten samples. The shearing strength of raw konnyaku and the effect of heating on konnyaku are larger in konnyaku of western Japan than in that of eastern Japan. All over Japan, a significant correlation is observed between KM content and shearing strength; the higher the KM content, the larger the shearing strength of konnyaku is.
2) The weight of a piece of konnyaku of eastern Japan on the market is significantly large, whereas the solid matter content significantly higher in konnyaku of western Japan. However, the price per KM 100g is higher in konnyaku of eastern Japan.
3) The contents of ash, calcium and sodium, and pH are significantly higher in konnyaku of western Japan. A significant correlation is observed between KM content and ash content; the higher KM content, the higher the ash content.
4) It seems that the konnyaku of northern Japan is softer, and that of western is harder.
