Curd-Ripening Evaluation by Flow Injection Analysis of L-Lactic Acid with an Electrochemical Biocell during Mozzarella Cheese Manufacture

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• 作者：Marco Esti ; Maria Cristina Messia ; Ennio La Notte ; Pietro Lembo ; Dario Compagnone ; and Giuseppe Palleschi
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：1996
• 出版时间：October 1996
• 年：1996
• 卷：44
• 期：10
• 页码：3102 - 3107
• 全文大小：204K
• 年卷期：v.44,no.10(October 1996)
• ISSN：1520-5118

文摘

A flow injection analysis procedure was used for the determination ofL-lactic acid during theproduction of mozzarella cheese. The apparatus consists of anelectrochemical flow-through wall-jet cell assembled with a platinum sensor covered with the immobilizedlactate oxidase enzymeand connected to an amperometer. This system was used to monitorthe concentration of L-lacticacid produced by lactose fermentation catalyzed by selected startersduring cheese manufacture.Lactate was detected in the range (5 ×10^-6)-(1 ×10^-4) mol/L with a detection limit of 2 ×10^-6mol/L. L-Lactate has been measured in raw milk andduring the manufacture of cow and waterbuffalo mozzarella cheese. The starter used was a commerciallyavailable strain of Streptococcusthermophilus. Real time analysis of lactate allowed a controlof the curd-ripening evolution atdifferent pasteurization temperatures of the milk. Values oflactic acid were compared with pHvariation during the process. This method proved to be moresensitive than the pH measurementprocedure for the control of the continuous production of lactic acidparticularly near the "stretchingpoint" when very slight pH variations were observed.Keywords: L-Lactate biosensor; amperometry; mozzarella cheese;water buffalo and bovine milk;curd and whey; ripening; pasteurization