Консервирование проб сырого молока пищевой добавкой низин (Е-234)

Abstract

In order to preserve the initial organoleptic, physico-chemical and microbiological parameters, raw milk samples for veterinary and sanitary examination are transported to the laboratory in a chilled form within a short period of time. Preservatives, which eliminate the need to cool samples, affect the initial milk parameters, pose a danger to laboratory workers and change organoleptics. This paper presents data on the effect of the safe food additive nizin (E-234) at a concentration of 0,03 g/0,5 l on the initial organoleptic (taste, color, odor and consistency) and physico-chemical (mass fraction of fat, protein, skimmed milk residue (SOMO), density, titrated acidity) indicators milk stored at room temperature. It was found that nisin slows down the change in physico-chemical parameters due to spoilage, but causes an increase of 0,14 % in the mass fraction of protein, 1,28 kg/ m3 in density, 0,32 % in the mass fraction of SOMO after 24 hours of experiment. Two methods of reducing the concentration of nisin in the samples were tested: heat treatment of milk and dilution of the preservative before each application. Heat treatment had a weak effect, the indicators decreased by an average of 0,04 %, 0,07 %, 0,22 kg/m3 for protein, SOMO and density, respectively. The second method turned out to be simpler and more effective – the true values of protein, SOMO and density indicators were preserved for the first 6–18 hours of sample storage.