Localised air delivery systems in the food industry

The transfer of contamination through the airborne route is significant in the assembly area of high-care food factories preparing products such as sandwiches, prepared salads and chilled meals. This paper describes equipment designs that have been proposed to restrict such contamination and maintain low air temperatures around the food whilst allowing higher factory temperatures. Designs based on unidirectional directional flows, open troughs, semi-closed and closed tunnels are described. The uni-directional flow systems have been applied successfully in the chilled food industry although they require higher air flows than the other systems. Troughs offer good maintenance of temperature and low airborne counts around the food. Tunnels are more expensive and there are concerns about clean-ability of the equipment and, with the closed tunnels based on glove-box technology, potential problems of operator comfort. (C) 2001 Elsevier Science Ltd. All rights reserved.