Alternative Thermal Processing Technique for Liquid Foods-membrane Processing

Abstract

Liquid foods are sensitive to temperature and concentration by conventional methods results in product deterioration. Alternative processes, such as freeze concentration, have the drawback with respect to the maximum achievable concentration (only up to 40 to 45°Brix). In recent years membrane processes such as Microfiltration, Ultrafiltration and reverse osmosis are gaining importance for the concentration of liquid foods. Since heat is not involved in this process, it is also called Alternate thermal processing technique. This process can be employed as a pre-concentration step to reduce water load on subsequent processing steps and can be easily scaled up. Liquid foods such as fruit juices are of high nutritive value as they are naturally enriched with minerals, vitamins and other beneficial components required for human health. When extracted from their sources fruit juices have low solid content, color strength and high-water load. Recent advances and developments in this membrane processing used for the concentration of liquid foods are discussed here.