S. Sakura et al., EVALUATION OF SIMPLE QUICK MEASUREMENT OF PH IN SURIMI BY DIRECT INSERTION OF AN ELECTRODE, Nippon Suisan Gakkaishi, 59(7), 1993, pp. 1155-1162
Surimi, a processed fish product, consists mainly of protein and water
. Although surimi contains about 70% water, the concentrations of prot
eins are so high that surimi is quite viscous, taking the appearance o
f a gel. It is also rich in sugar. Several aspects were studied in ord
er to apply a method of direct insertion of a pH glass membrane electr
ode in the special medium of surimi. The result shows that it is possi
ble to measure pH by introducing a pH electrode directly. Fresh surimi
pH values measured by direct insertion were in the range of 6.97-7.06
. From these values it is concluded that the pH is partially due to my
osin and action proteins and partially to sodium polyphosphates used a
s preservatives. The low pH value of surimi indicates bacterial putref
action. The direct insertion method applied to defrosted surimi at 10-
degrees-C was easier, more convenient, more accurate, and more reprodu
cible with a quick response than the traditional method of aqueous ext
raction.