Heat exchanger solutions for 5 challenging foodstuffs
Thermal treatments using heat exchangers, such as pasteurisation, heating and cooling, feature in the manufacture of multiple food and drink products. In this article we look at five of the most challenging foodstuffs in terms of thermal processing, and the heat exchanger solutions to help manufacturers handle them correctly. Highly viscous materials Highly viscous foods, including nut butters and other fat-based products, can be almost solid at low temperatures. This creates a number of challenges, including moving the material through the heat exchanger. Other considerations include preventing fouling and ensuring an even temperature. Nut butter can be one of the most difficult products to handle, and so a heavy duty rotating scraped surface heat exchanger (SSHE) is required. With its larger motor, bigger scrapers and extra mounting supports, the HRS RHD Series was specifically designed for such tough materials. Products containing pieces The challenge when dealing with pieces of product (from small, diced vegetables to large fruit pieces) is ensuring the mixture moves through the process at a constant speed without damaging the physical integrity of the product. The Unicus Series of reciprocal SSHE is perfect as the separately controlled hydraulic scrapers are available in a range of designs and are fully controllable. Thermally challenging products Some ingredients, such as eggs or chocolate, are very sensitive to temperature and must be processed at precise temperatures to avoid damaging the product. Liquid egg, for example, is extremely delicate as the proteins in egg are more sensitive to heat than other products, such as milk or juices. The white and yolk are distinct components with different compositions and behaviours: egg white is denatured at 58°C while yolk is denatured at 65°C. If not handled correctly, thermal pasteurisation can decrease protein content, change physical characteristics such as texture and colour, and increase product […]