A comparison of the cooking performance of different appliances when following food manufacturers' instructions
The purpose of this research was to measure the temperature achieved in, and the microbiological count of, chicken burgers cooked following the preparation instructions given by the manufacturers. The work investigates the cooking of chicken burgers, manufactured by four different companies, cooked at different positions under a grill. Three appliances were used. Each showed uneven distribution of heat and a hot position and cool position was established for each grill. Differences in the temperature of the burgers cooked at different positions on the grills were also found. The burgers at the cool position attained a much lower cooking temperature and had a higher number of microorganisms surviving the cooking. The grill that produced the highest temperatures in the burgers had the lowest number of organisms surviving in the burgers. Only 24 out of the 72 burgers cooked to the manufacturers' instructions attained temperatures above 70°C. Some of the burgers appeared to be cooked when visibly assessed, but the core temperatures were low and had high microbial counts. The results obtained indicate that not all the cooking instructions were satisfactory and not all the appliances performed satisfactorily.
FOOD SAFETY IN THE HOME: CURRENT MICROBIOLOGICAL PERSPECTIVES
Despite the publication of two comprehensive reports (Richmond I and II) on the microbiological safety of food, together with new legislation, there has been little direct action concerning food safety in the home. Of particular relevance has been new research data which have shown that smaller numbers of bacteria are able to cause food poisoning, which stresses the importance of cross‐contamination. Doubts also have been raised about the safety of cooking raw meat in microwave ovens. Of perhaps greater impact have been the increased demands of food manufacturers and consumers on refrigeration. This has resulted, for example, from the increasing popularity of convenience foods and a reduction in the use of preservatives. Furthermore, many bacteria implicated in food poisoning are able to grow at relatively low temperatures. Recommendations include new standards by manufacturers of refrigerators and microwave ovens, together with a greater awareness and education of food safety issues.
On the fractionation of β-lactoglobulin and α-lactalbumin
Abstract Existing methods for the preparation of α-lactalbumin and β-lactoglobulin are examined critically. It is proposed that the most satisfactory method for the preparation of the whey protein fraction from bovine milk is (NH 4 ) 2 SO 4 fractionation. A number of new gentle procedures for the fractionation of the whey proteins are compared with some existing methods. The distribution of total protein at various stages is determined by total Kjeldahl nitrogen and the kind of protein by starch-gel electrophoresis. The effect of variables, such as pH, salt concentration and temperature on the separation of α-lactalbumin and serum albumin from β-lactoglobulin is studied. Differences in the behavior ( e.g. solubility) of genetic variants of β-lactoglobulin are noted. The solubility of each of the major whey proteins, under similar conditions to those used in the fractionation, is compared with its solubility in the whey protein mixture. The understanding gained of factors important in the fractionation is used in recommending new procedures for α-lactalbumin and β-lactoglobulin isolation.