화학공학소재연구정보센터
Journal of Food Engineering, Vol.67, No.1-2, 81-86, 2005
Production of extended-shelf life milk by processing pasteurized milk with pulsed electric fields
Thermally pasteurized milk bulk-shipped to distant places is usually pasteurized for a second time after arrival at the point of consumption. Such double thermal treatment has the potential to reduce the sensory and nutritional quality of milk; hence the use of a nonthermal preservation method was investigated. High-temperature short-time (HTST) pasteurized milk was treated with five pulsed electric fields (PEF) having peak electric field of 35 kV/cm and 2.3 mus of pulse width, at a temperature of 65degreesC for less than 10s. PEF treatments were applied either immediately after thermal pasteurization to produce an extended-shelf life product, or eight days after thermal pasteurization to simulate processing after bulk-shipping. Application of PEF immediately after HTST pasteurization extended the milk's shelf life to 60d, while PEF-processing after eight days caused a shelf life extension of 78d, both proving to be successful strategies to extend the shelf life of milk. (C) 2004 Elsevier Ltd. All rights reserved.