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Żywieniowe i technologiczne uwarunkowania zmniejszania zawartości laktozy w mleku i produktach mlecznych

Świątek M., Bednarski W., Śliwiński M.

Przemysł Spożywczy

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2018

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T. 72, nr 10

26--29

PL

W pracy omówiono znaczenie laktozy w żywieniu. Wskazano na problem hipolaktazji i nietolerancji laktozy, z istotnym wpływem czynników etnicznych i genetycznych. Przedstawiono możliwości diagnostyczne i sposoby leczenia nietolerancji laktozy. Opisano właściwości preparatów β-galaktozydazy oraz aspekty technologiczne pozyskiwania produktów z rozłożoną laktozą. Przedstawiono zalecenia dotyczące diety bezlaktozowej i wskazano na potrzebę zwiększenia asortymentu produktów z obniżoną zawartością laktozy. W pracy wskazano poziomy progowe laktozy w niektórych krajach UE, w odniesieniu do stosowania określeń „bez laktozy” i „niska zawartość laktozy”.

EN

This work discusses the importance of lactose in nutrition. The problem of hypolactasia and lactose intolerance is pointed out, with significant influence of ethnic and genetic factors. Diagnostic possibilities and methods of treatment of lactose intolerance are presented. The properties of β-galactosidase preparations and technological aspects of obtaining products with hydrolised lactose are discussed. Recommendations regarding a lactose-free diet are presented and the need to increase the range of products with reduced lactose content is indicated. This paper indicates the threshold levels of lactose in some EU countries with reference to the use of the terms “lactose-free” and “low-lactose”.

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Hydrolysis of lactose from cheese whey using a reactor with [beta]-galactosidase enzyme immobilised on a commercial uf membrane

Regenhardt S.A., Mammarella E.J., Rubiolo A.C.

Chemical and Process Engineering

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2013

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Vol. 34, nr 3

375--385

EN

In this study, [Beta]-galactosidase enzyme from Kluyveromyces fragilis was immobilised on a commercial polyethersulfone membrane surface, 10 kDa cut-off. An integrated process, concerning the simultaneous hydrolysis–ultrafiltration of whey lactose was studied and working conditions have been fixed at 55[degrees]C and pH 6.9, the same conditions that are used for the industrial process of protein concentration. For the immobilisation, best results were obtained using 5% (v/v) of glutaraldehyde solution and 0.03 M galactose; the total activity recovery coefficient (TARC) was 44.2%. The amount of immobilised enzyme was 12.49 mg with a total activity of 86.3 LAU at 37[degrees]C, using 5% (w/v) lactose solution in phosphate buffer (100 mM pH 6.9). The stability of the immobilised enzyme was approximately 585 fold higher in comparison with the stability of free enzyme. Multipoint covalent immobilisation improves the stability of the enzyme, thereby enhancing the decision to use the membrane as a filtering element and support for the enzyme immobilisation.

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Immobilization of Aspergillus oryzae Β galactosidase on concanavalin A-layered calcium alginate-cellulose beads and its application in lactose hydrolysis in continuous spiral bed reactors

Ansari S. A, Husain Q.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 4

15-20

EN

In this study, Aspergillus oryzae Β galactosidase was immobilized on concanavalin A layered calcium alginate-cellulose beads as a bioaffi nity support. Immobilized enzyme showed a remarkable broadening in temperature-activity profi les as compared to the native enzyme and exhibited 65% activity in the presence of 5% galactose. Michaelis constant (Km) was 2.57 mM and 5.38 mM for the free and the immobilized Β galactosidase, respectively. Crosslinked Β galactosidase showed greater catalytic activity in the presence of Mg2+ and was more stable during storage at 4°C for 6 weeks. Immobilized enzyme hydrolyzed 67% lactose in milk in 8 h and 85% lactose in whey in 9 h in the stirred batch process at 50oC. The continuous hydrolysis of lactose by crosslinked Β galactosidase in spiral bed reactor exhibited 93% and 88% hydrolysis of lactose at flow rate of 20 ml/h and 30 ml/h, after 1 month operation, respectively.