220 likes | 804 Views
Lactose intolerance and the production of lactose-free milk. Ein Beitrag im Rahmen des Projekts. Durchgeführt und präsentiert von den Chemisch-Technischen Assistenten an der. Index. Incidence of lactose intolerance Cause of lactose intolerance Symptoms of lactose intolerance
E N D
Lactose intoleranceand the production of lactose-free milk Ein Beitrag im Rahmen des Projekts Durchgeführt und präsentiert von den Chemisch-Technischen Assistenten an der
Index • Incidence of lactose intolerance • Cause of lactose intolerance • Symptoms of lactose intolerance • Help for lactose intolerant persons • Lactose-free milk and milk products • Large-scale production of lactose-free milk • Lab-scale production of lactose-free milk • References 20 October 2009 Klasse 2BKC2
Lactose intolerance Many people have problems with the digestion of milk and milk products: Drinking a glass of milk will have unpleasant side effects for them. Worldwide more than 80% of adults cannot digest the milk sugar lactose: This condition is called lactose intolerance. 20 October 2009 Klasse 2BKC2
Occurence of lactose-intolerance 20 October 2009 Klasse 2BKC2
Yet, lactose-intolerant adults began their lives drinking milk from a bottle or breast and digesting it completely. Babies produce the enzyme lactase in their small intestine. This enzyme breaks down lactose. Therefore: Babies are lactose tolerant 20 October 2009 Klasse 2BKC2
Lactase Lactase acts as a pair of molecular scissors: It snips the disaccaride lactose in two simple sugars, galactose and glucose: Lactose tolerant individuals produce lactase for life. For them, a bar of milk chocolate is a pleasant experience. 20 October 2009 Klasse 2BKC2
80 % of adults worldwide do not produce lactase For them, the pleasure of eating chocolate, a scoop of dairy ice cream or some cheese has unpleasant consequences. 20 October 2009 Klasse 2BKC2
Symptoms oflactose intolerance: bloated feeling, stomach cramps diarrhoea nausea, vomitting flatulence 20 October 2009 Klasse 2BKC2
„Help“ for people with lactose intolerance Undigested lactosein the small and large intestine is the common cause for the nasty discomforts suffered by lactose intolerant persons. • lactase–tablets • to be taken with lactose containing meals • lactose-freemilkproducts • produced by breaking down lactose using lactase • sour milk products • lactose converted to lactic acid using microbes 20 October 2009 Klasse 2BKC2
Market for lactose-free products on the rise Increasing demand from developing countries Increasing range of healthy and tasty lactose-free milk products ice cream yoghourts cheese pudding cream in coffee Most of these are produced by OMIRA 20 October 2009 Klasse 2BKC2
Large-scale industrial production of lactose-free milk • Lactose is split into glucose and galactose by adding the enzyme lactase to milk • Production of lactase enzyme is expensive: • It is manufactured by microorganisms and has to be purified from these. • Key to economic production of lactose-free milk: Immobilization of lactase • Lactase is included within a matrix; milk is continuously pumped through it • No residual lactase in milk • Enzyme can be re-used frequently 20 October 2009 Klasse 2BKC2
Lab-scale in vitro production of lactose-free milk: Immobilizationof Lactase by Na-alginate • Enzyme solution is prepared • and mixed with the Na-alginate solution • Mixture is dropped into a solution of calcium chloride • to harden the alginate beads • The lactase-beads are collected. • They can be re-used for about a month. 20 October 2009 Klasse 2BKC2
MinusL • The lactase-beads are added to conventional cow‘s milk, whey, or lactose-solution + • Cleavage of lactose into galactose and glucose is detected by glucose test strips 20 October 2009 Klasse 2BKC2
Results Lactose cleavage by lactase as a function of time judged by Glucose test sticks 20 October 2009 Klasse 2BKC2
Lactose Lactose + Lactase Results Cleavage of lactose by lactase was also confirmed by HPLC: 20 October 2009 Klasse 2BKC2
References: http://www.familiesonline.co.uk/article/articleview/1399/1/22/ http://www.spiegel.de/img/0,1020,122495,00.jpg http://valiblog.files.wordpress.com/2008/08/babyflasche.jpg46 http://en.wikipedia.org/wiki/File:LacIntol-World2.png http://www.foodreactions.org/colic/ http://www.meuterei2008.de/fileadmin/templates/_gfx/sponsor_minusl.jpg 20 October 2009 Klasse 2BKC2