MATHEMATICALLY OPTIMISING THE CRUST FREEZING OF PORK LOINS
Many companies as part of their current high speed portioning process for pork joints apply a short freezing process to crust freeze the joints prior to portioning. Previous studies on such processes have shown that the amount of freezing and the resulting temperature gradient through the joints has a substantial affect on yield and quality of cut.The optimum temperature profile will depend on the material to be cut and the type of cutting system used. For example, the thickness of the surface fat layer will substantially affect heat flow and the amount of ice in the joint. The amount and distribution of ice controls the rigidity and hence the cut-ability of the portion. Using purely experimental methods to determine the optimum conditions required for a crust freezing operation is very costly and time consuming due to the wide range of variables that need to be investigated and the range of products of interest. It is also very difficult to measure the refrigeration extraction rate required.A finite difference model of an infinite cylinder has been developed and used to predict the temperature profile in pork loins of varying thicknesses with and without a surface layer of fat after 0.5, 1, and 1.5 h. The predictions carried out show the affect of temperature, air velocity, thickness of meat and amount of fat on the temperature gradient through the joint. In addition to these data the program will also give data on the amount of heat that has to be extracted, i.e. refrigeration power required and the average joint temperature at any time.
C.JAMES S.PALPACELLI S.JAMES A.FOSTER
Food Refrigeration & Process Engineering Research Centre (FRPERC), University of Bristol, Churchill Building, Langford, North Somerset, BS40 5DU, UK
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）