Dalgaard P, Mejlholm O, Huss H H
Danish Institute for Fisheries Research, Department of Seafood Research, Technical University of Denmark, Lyngby, Denmark.
Int J Food Microbiol. 1997 Sep 16;38(2-3):169-79. doi: 10.1016/s0168-1605(97)00101-3.
An iterative approach was used to develop a microbial model for shelf-life prediction of cod fillets packed in modified atmospheres. The effect of temperature (0-15 degrees C) and CO2 (0-100%) on growth of the specific spoilage organism, Photobacterium phosphoreum, was studied in packed cod and in liquid media. P. phosphoreum was a dominant part of the spoilage microflora of packed cod stored at the extremes of the range of conditions studied. The organism is therefore likely to be important for spoilage and the development of a microbial model within this domain seems relevant. A liquid medium was developed to provide growth kinetics of P. phosphoreum similar to those observed in packed cod. Using this medium, the effect of temperature and CO2 on the maximum specific growth rate of Photobacterium phosphoreum was determined by absorbance measurements and modelled by a square root equation and by a polynomial equation. Product validation studies were carried out during summer and winter using naturally contaminated packed cod fillets which were stored at constant and at changing temperatures. The shelf-life of the packed fillets was predicted on the basis of the initial numbers of P. phosphoreum, product temperature profiles and the level of CO2 in the modified atmosphere. The average deviations between shelf-life determined by sensory evaluation and shelf-life predicted by the square root equation and by the polynomial equation were 17% and 9%, respectively.
采用迭代方法建立了一种用于预测气调包装鳕鱼鱼片货架期的微生物模型。研究了温度（0 - 15摄氏度）和二氧化碳（0 - 100%）对特定腐败菌——磷发光杆菌在包装鳕鱼和液体培养基中生长的影响。在研究的条件范围极端值下储存的包装鳕鱼中，磷发光杆菌是腐败微生物群落的主要组成部分。因此，该菌可能对腐败起重要作用，在此领域开发微生物模型似乎具有相关性。开发了一种液体培养基，以提供与在包装鳕鱼中观察到的类似的磷发光杆菌生长动力学。使用该培养基，通过吸光度测量确定温度和二氧化碳对磷发光杆菌最大比生长速率的影响，并分别用平方根方程和多项式方程进行建模。在夏季和冬季进行了产品验证研究，使用自然污染的包装鳕鱼鱼片，将其分别储存在恒定温度和变化温度下。根据磷发光杆菌的初始数量、产品温度曲线和改良气氛中的二氧化碳水平预测包装鱼片的货架期。感官评价确定的货架期与平方根方程和多项式方程预测的货架期之间的平均偏差分别为17%和9%。
