Special Report 213 Chemical Weekly October 1, 2013 Enzyme-assisted extraction of bioingredients I n the modern world, bioingredi- ents have an important role to play in different spheres of human life. They can be a major component of food we eat; beverages that quench our thirst; medicines that cure our illness; cosmetics that make us beautiful and clothes that make us fashionable. So the demand for bioingredients is increasing day by day. Modern science and tech- nology is being challenged by the rising demand from society for development of new bioingredients, sources and method of isolation. Bioingredients are the active prin- ciples of plants and are generated in the plants either by the primary or second- ary metabolic reactions taking place during the course of plant growth. The primary metabolites of plants are mainly lipids, protein and carbohydrates. The secondary metabolites are classified into three main groups: phenolics, ter- penoids and alkaloids. As a consequence of the increased demand for bioingredients like essential oil, natural colours, pure components from the industries, there is a need for extensive collection of information on the composition of bioingredients and their recovery methods. The extraction of bioingredients from plant material can be achieved by a number of different methods, like:  Expression;  Distillation (hydro- or water-distil- lation, water and steam distillation, steam distillation);  Solvent extraction;  Super Critical Fluid Extraction (SCFE); and  Enzyme assisted extraction. For each method there may be many variations and refinements and the extraction may be conducted under reduced pressure (vacuum), ambient pressure or excess pressure. The choice of extraction method will depend on the nature of the material, the stability of the chemical components and the speci- fication of the targeted product. Expression Expression is used exclusively for the extraction of citrus oil from the fruit peel, because the chemical components of the oil are easily damaged by heat. Citrus oil production is now a major by- product process of the juice industry. Distillation Distillation is a physical process used in most of the industries to iso- late the volatile portions of plant ma- terials. The main advantage of distilla- tion is that it can generally be carried out with some very simple equipment, close to the location of plant produc- tion. Even in relatively remote loca- tions large quantities of material can be processed in a relatively short time. There are various types of distillation methods like hydro distillation, water and steam distillation and steam distil- lation. The selection of the distillation method depends on the nature of the plants and their parts. Water distillation is the simplest of the three distillation methods. It is one of the oldest methods of distilla- tion used. The plant material is mixed directly with water in a still pot. A perforated grid may be inserted above the base of the still pot to prevent the plant material settling on the bottom and coming in direct contact with the heated base of the still and resulting in charring. The spice is fully immersed in hot water. The result is a soup, which carries aromatic molecules of the plant. The method is not much in use these days, because of the risk of overheating K.C. BABY Lead-Sales Application Bio-Ingredients Division Synthite Industries Ltd. E-mail: babykc@synthite.com DR. T.V. RANGANATHAN Professor Food Processing and Engineering Karunya University, Coimbatore E-mail: srivarahe@gmail.com