2013 Volume 21 Issue 4 Pages 46-52
Usually a mixture of several kinds of coagulants is used in the manufacture of tofu. The subject of this study was a typical mixed coagulant, a blend of magnesium chloride for old-fashioned taste and GDL(glucono-δ-lactone), which simplifies control of the coagulation speed. There was concern that this coagulant might tend to cake, but there had been no major caking trouble for more than ten years up until 2011, when there were a large number of complaints about caking.
Severe caking was recognized in an experiment using an actual sample. In this study, utilizing the reproducibility of the problem of obvious caking, a redesign of the coagulant was undertaken. An attempt was made to solve the caking problem of the mixed coagulant by using the quality engineering methodology of parameter design to clarify the control factors strongly related to caking. Parameter design was performed for the coagulant using estimated caking conditions and tofu manufacturing conditions. Conditions under which a Iong caking time could be obtained were determined from the smaller-is-better S/N ratio. A coagulant that resists caking even at about 40 degrees Celsius, which is thought to be the highest temperature used in Japan, was obtained.
