Recent studies have highlighted the importance of degree of doneness in consumer satisfaction of steaks. In a recent survey of 3,554 consumers, 30% considered that their steaks were not delivered to their ordered degree of doneness. There was a large penalty in consumer satisfaction scores if steaks were not delivered to the ordered degree of doneness, with a larger penalty for over rather than under cooking.

However despite the importance of steak doneness to the food service industry, it has received relatively little attention by researchers over the years. Generally doneness has been assumed to be simply a function of internal temperature. In an earlier study conducted with Qantas Inflight service Catering we showed that the combination of internal steak temperature, pH, steak thickness and steak weight accounted for 70% of the variation in degree of doneness. This study showed that even after adjusting for these factors, the residual standard error was still (0.7 doneness units, indicating that 48% and 16% of the steaks would still vary by at least (0.5 and (1.0 doneness scores, respectively. Therefore even with tight adherence to specification these results still suggest considerable variation in doneness. However in a 'real world situation' there would be much greater variation in these traits, and it is therefore unlikely that the tolerances in the above experiment would be easily achieved in industry.

If meat science is to address the problem of variation in degree of doneness it is important to initially develop a system whereby the doneness of a steak or roast can be objectively described. Once this has been achieved it is necessary to quantify what variation exists in the doneness/temperature relationship. To date the variation has only been quantified in terms of a subjective score for doneness. If, as suggested by a number of studies in the literature, substantial variation does exit in objectively measured doneness at the same internal cooked temperature then a research program to identify these sources of variation and their control in a the food service industry will be undertaken to increase the consistency of steaks cooked in a commercial environment. If there is little variation in the doneness/temperature relationship then the research at the Beef CRC will focus on factors which affect heat transfer in steaks. At the same time the effect of heat transfer mechanisms on sensory attributes will be investigated.

The objectives for the Beef CRC cooking program are as follows: