EVALUATION OF SIMPLE QUICK MEASUREMENT OF PH IN SURIMI BY DIRECT INSERTION OF AN ELECTRODE

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.