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Muscle is considered a sterile tissue. However, the butchering practices used to prepare cuts of meat used for steaks introduce micro-organisms onto the surface. These may be primarily those associated with spoilage e.g. Pseudomonas species, but bacterial pathogens including Salmonella, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and pathogenic spore formers can also be introduced by the same operations. When rare steaks are cooked, the surface of the meat is cooked but the interior remains raw. Temperatures reached at the surface should be high enough to eliminate vegetative cells and in theory the steak should not prove hazardous even though the centre is uncooked. This is in contrast to comminuted meat products (e.g. hamburgers) where the bacteria become distributed throughout the product during mincing of the meat and thorough cooking is needed to remove all these risks. <P>
However, this consideration is based on the two premises: that the interior of muscle is sterile and that minimal cooking associated with rare steaks kills all vegetative cells on the surface. This work aims to demonstrate that rare steak is a microbiologically safe product.
The specified cooking procedure reduced total aerobic counts to < 102 cfu/g and eliminated the risk of vegetative pathogens including E. coli. The potential for cross contamination from raw surfaces onto cooked surfaces via the tongs used in cooking was identified as a risk factor, but both treatment in water at 82°C or use of alcowipes on the tongs after contact with a raw surface eliminated this problem. Based on these findings, guidelines for the cooking of rare steak could be produced for the industry.