: Modified atmosphere packaging is becoming increasingly common. It has been claimed that the technique enables significant shelf-life extension but in so doing presents an increased public health risk. This paper reviews the literature relating to the scientific basis of these claims. It demonstrates that shelf-life, sensory quality and safety of packaged products may be optimised only by harmonising a complex relationship between product and process.

This study examined the effects of sous vide (i.e. vacuum packaging) upon the sensory characteristics of chicken breast and of sliced potatoes in cream both immediately after cooking and following subsequent chilling, chilled storage and reheating. Cooking was to a range of end point temperatures (70 ЊC for 2 minutes, 80 ЊC for 10 minutes, 80 ЊC for 30 minutes) and chilled storage was for 2,5 or 7 days at 5 ЊC. The products were evaluated by separate sensory panels, each comprising either 25 or 10 trained assessors using attribute scaling methods. With both 80 ЊC heat treatments, sous vide significantly increased the flavour intensity of both products (P Ͻ 0.05) and the juiciness and moistness of the chicken and potato respectively (P Ͻ 0.05) compared to nonvacuum packed freshly cooked products. In general, higher hedonic scores were associated with higher flavour and juiciness scores for chicken and with higher flavour and moisture scores for potato. The hedonic appeal results indicate that, contrary to what has been widely assumed, these changes may not always be desirable in terms of product acceptability. The data also indicate that, in some products, the heat treatments necessary to ensure microbiological safety cause an appreciable loss of sensory quality. Sensory evaluation methodologyPart 1 Assessors were selected from a pool of volunteers Sous vide potatoes and carrots I.

Cook-chilled products are increasingly produced in the catering and food processing industries. It is claimed that the application of vacuum packaging followed by processing in-pack (sous vide technology) improves both shelf life and eating quality, but in doing so presents an increased public health risk. This paper reviews the literature relating to the scientific basis of these claims. It demonstrates that, although they have some theoretical foundation, in practice they are unsubstantiated by research. KeywordsCatering foods, convenience foods, eating quality, microbiological safety, shelf life, vacuum packaging. * Correspondent. Fax: +44 532 83311 1.

Cook-chill systems are now widely used within the catering industry. The basic method has been enhanced by the use of vacuum packaging to extend shelf-life; and, it is claimed, sensory quality. This paper reviews the literature available on the sensory quality of foods produced by conventional and enhanced cook-chill methods. It shows that the sensory quality of foods produced by these methods has received little attention from researchers, despite, in the case of methods using vacuum packaging, some extravagant claims about improved eating quality. Most attention has been paid to meat products. Deteriorative changes are shown to occur rapidly, but many variables affect the end result, which is often product and process specific. Lack of standardization, both in the catering industry and in experimental methods, makes comparisons between studies difficult.