Quality of Fresh Bovine Milk after Addition of Hypothiocyanite-rich-solution from Lactoperoxidase System

Abstract

Lactoperoxidase system (LPOS) has received high attention for milk preservation in the certain countries, because the system exerts hypothiocyanite ion to inhibit the growth of broad spectrum of bacteria. Since the system might be remained the substrates of thiocyanate (SCN-) and hydrogen peroxide (H 2 0 2 ) and the activity of LPO might be inhibited by compounds in milk, this research has been done for generating hypothiocyanite-rich-solution to be added in fresh milk. The solution was obtained from the reaction solution ofLPO, SCN- and H 2 0 2 . The remaining substrates in the reaction solution were detected spectrometrically. LPO was obtained from bovine whey using SP-Sepharose Fast Flow. Untreated bovine fresh milk (1 h after milking) was added with 1 % (v/v) ofhypothiocyanite-rich-solution and store at 30°C for 6 h. The addition of sterile water has been used instead of the solution for control. It is concluded that hypothiocyanite-rich-solution contained very less amount of substrates. Hypothiocyanite-rich-solution remarkably decreased the total bacteria count in the fresh milk at 6-h incubation. The solution was also kept the pH value in fresh milk during 6-h incubation. This result might open the new way of practical use ofLPOS to preserve fresh milk using the hypothiocyanite-rich-solution.