The primary chilling of poultry carcasses—a review

This paper reviews the published scientific studies that have been carried out on the chilling of poultry carcasses. The prime purpose of chilling is to limit the growth of both pathogenic and food spoilage microorganisms. There are a wide range of publications that show that, in general, the numbers of both types of microorganism, on the surface of poultry carcasses, is reduced during the chilling process. Immersion or spin chilling is not used in the production of ‘fresh’ chilled poultry in Europe, ‘dry’ air chilling being the preferred chilling method. Many people believe that there is some clear microbiologically based reason behind the selection of air chilling. However, the published data do not appear to support this belief, and if anything point to a microbial advantage of immersion systems. The rate of chilling has some influence on the taste, texture and appearance of poultry meat. Very rapid chilling can result in tougher chicken meat, while very slow chilling can produce pale soft exudative (PSE) muscle. However, in both cases the effect is not as marked as with red meat. No comprehensive published data has been found on the effect of a range of chilling systems, chilling conditions, carcass weight and shape on the rate of chilling, weight loss and heat loss. Without such data it is impossible to optimise the design of a poultry chilling system.