Applications in the food industry
For years now, enzymes found application in various sectors of the food industry. Alpha amylases have been the very first enzymes used in the bakery industry to improve the volume and softness of products and reduce starch degradation. The success obtained nowadays by enzymes derives from their functionality and the possibility of reducing or even replacing additives, among which, for instance, emulsifiers. DATEM (E472e or Diacetyltartaric esters of monoglycerides) used to improve the structure of the gluten network and, hence, the final product volume, can be replaced by lipases that produce a complex mix of products acting similar to emulsifiers, with the same end effect. Thus, a clean list of ingredients can be obtained, next to a reduction of recipe costs. An important fibre family is represented by the components of caryopsis: Hemicelluloses and pentosans (arabinoxilans and arabinogalactans). Hemicelluloses are complex polysaccharides consisting of a chain of xilosteum molecules, branched with arabinose chains. Hemicelluloses (occurring in fl our at a level of 2%) are insoluble, and hinder the formation of the gluten network. Pentosan molecules are present in small quantities in fl our (approx. 1%), and can absorb ten times their weight of water. Hemicellulases are a generation of enzymes (pentosanase and xylanase) that convert insoluble fibres into soluble ones. They improve the product softness by enhancing water absorption in the dough. The interaction of the products obtained with hemicellulases that bind with the water present in the dough is similar to that of emulsifiers. In the milk and dairy industry, next to the enzymes used for cheese-making (microbial rennet and calf chimosin used as milk coagulants), lipases are used for fats degradation and lactases are used to break down milk sugar (i.e. lactose) into its basic components, to obtain lactose-free milk that can be given to persons displaying a reaction to milk. In the beverage industry, papain and pectinase are most frequently used as clarifying agents for fruit-based beverages . In winemaking, in the maceration phase, pectolytic enzymes with hemicellulase activity are used that favour the extraction and controlled clarification of must; those with b-glycosidasic activities are used in the selection of “non aggressive” tannins, and for the diffusion of aromas precursors from the grape; those with β-glucanase activity can
break down the glucane chain for simpler pressing, clarification and filtration during wine refining.
New application possibilities
An enzyme has been recently set up to reduce acrylamide formation while cooking or frying foods (mainly bakery products and snacks), with the possibility of reducing toxic molecules generated during industrial processing. In April 2002, Swedish researchers discovered that considerable amounts of acrylamide – a potential tumour inducing substance – can be found in cooked or fried foods. This occurs more frequently in amylaceous products, which, when heated at very high temperatures, form acrylamide as a result of the reaction between reducing sugars and asparagine. Asparaginase allows effective reduction of acrylamide formation by converting free asparagine into aspartic acid. Tests conducted at the AIB (American Institute of Bakery) and the Reading Bakery Systems (RBS) in co-operation with Novozyme, led to a 90% reduction of this molecule in bread, biscuits, cookies, and salted snacks, and of 85% in crackers. In the near future these molecules might be a possible solution to effectively reduce the use of additives in food recipes, thus contributing to reduce production costs and to create a new range of “E-Free” products. Many companies have already chosen this new path, with the support and co-operation of the sector’s pioneers.
Literature
Scheme B – Source
Ministero del Lavoro, della Salute e delle Politiche Sociali, Dipartimento per la sanitĂ pubblica veterinaria, la nutrizione e la sicurezza degli alimenti, Comitato Nazionale per la Sicurezza Alimentare PARERE N. 1 DEL17/07/2008: Lisozima nel Grana Padano
Laffrot – Info – No. 25, September 2002, Il lisozima
Laffrot – Info – No. 23, June 2002, R. Zinoni, Enzimi ad uso enologico: parametri di qualitĂ , fattori di rischio.
http://www.acrylaway.novozymes.com
