Enzymes have been employed in the detergent industry for years, they are depended upon to remove proteins, starches and lipids, which can come from blood, grass, sweat, milk etc. The main enzyme used in the detergent industry initially was protease, which catalyses the breakdown of protein molecules such as blood. However, recent developments have introduced a cocktail of enzymes which included lipases and amylases. Lipase's concentrate on the breakdown of fatty substances such as oils. They hydrolyse the ester bonds in triglycerides, which are a major component of fats. Amylase focuses on the breakdown of starchy deposits, from products such as food. The advantage of using these enzymes is that they are specific, thus removing the desired stain without damaging fabrics. Cellulases were also introduced because when detergents were used small fibres are raised from the surface of cotton thread, resulting in a change in the feel of the fabric and, particularly, in the lowering of the brightness of colours." Consequently cellulase was introduced to remove the small fibres, without damaging surrounding, major fibres. In addition enzymes (amylase and protease) are used in dishwashing detergents as they can remove food particles.
Enzymes play a major role in the brewing industry. In beer brewing, proteases from bacteria are added to prevent cloudiness and amyloglucosidases are utilized to produce low calorie beers. The yeast converts sugars into alcohol and carbon dioxide. However, these sugars are stored as starch in plants; consequently this meant the process of malting had to be undertaken. This process was relatively expensive and hard to control; therefore industrial enzymes such as amylases, glucanases and protease's were introduced to catalyse the malting process and make it easier to control. Thus producing the required sugars for the yeast to react on. In addition enzymes aid the filtration process, because of the polysaccharides; xylans and glucans present in the final beer. This often results in slow filtration. Consequently xylanases and glucanases are added to break down the polysaccharides, therefore increasing the filtration rates. Marx refuted hypothesis.
Many enzymes are applied in the baking industry. The wheat flour used in bread making naturally contains enzymes that modify the starch, protein and fibre fraction of the flour when water is added to the flour to make dough. In addition the yeast accommodates enzymes, which ferment maltose, which in turn produces carbon dioxide, making the bread rise.
Enzymes such as xylanase, a-amylase, protease, glucose oxidase and lipase are used for various reasons, such as controlling the taste, volume of the loaf, crumb texture and staling properties. Consequently correct enzymes must be used, otherwise this could have harmful effects on the dough
Enzymes are used in the food industry; for example rennet is used in cheese production and the many flavours in cheese are a result of protease action. Chymosin from genetically engineered microbes now has replaced rennin previously obtained from calves. Enzymes aid the processing of cooking; they can enhance flavours and aroma, remove unwanted flavours and modify texture. The main enzyme used in the food industry is protease, however, lipase's are becoming increasingly common. Enzymes are particularly used in the production of soy sauce, gelatin hydrolysis and the manufacture of pet food. However, enzymes can cause quality impairment when they continue to work beyond the point of perfection. Flavours, colour and texture can change as a result of this. For example the loss of colour in fruits can be due to hydrolysis of anthocyanins and changes in carotenoid pigments.
Enzymes also have parts in pharmaceuticals and diagnostic industries, however, the applications of enzymes have not been as extensive as other industries. The most successful applications are extracellular enzymes, which mean that they are secreted by the micro-organism which creates them. Enzymes have been used to treat genetic disorders, when some people are unable to produce the required enzymes.
The medical uses of enzymes are that an enzyme called L-asparaginase is thought to be a potent weapon for treatment of leukemia. Dextrinases may prevent tooth decay.
Proteases, naturally present in dog faeces are used to soften hides and remove hair in leather tanning. Blood clots which are made in damaged blood vessels as a result of the deposition of plaque (cholesterol derivative) on inner walls of blood vessels, which is known as atherosclerosis, are digested by specific protease enzymes from bacteria. Isolated enzymes have analytical uses like measuring the amount of glucose in the urine of diabetics. Bacterial lactase produces lactose free milk, which is used by people eho cannot produce lactase. In the production of fruit juice hemicellulases and cellulases break down fruit cell wallsand this increases the amount of juice from the fruit.
Citric acid is used in jam production and is produced by a mutant stain of the fungus Aspergillus niger, which makes the enzyme citrate synthase. Fungal ligninases are used in pulp and paper industries to remove lignin from wood pulp and treat wood waste. In soft centred chocolates, invertase from yeast breaks down the solid filling to produce the soft centre.
Enzymes are used in a variety of industries, for example to enhance flavour and as additives in brewing and detergents. They provide many advantages for different industrial processes. They have also benefited industries in terms of cost, with the introduction of techniques such as enzyme immobilisation. Enzymes have been widely used in the food industries making them more competitive and they have helped in medicine and pharmaceuticals. Consequently, enzymes will be used further in the future as technology progresses. In addition they are a vital part of a number of diverse industrial processes.
By Jegan Kanagalingam