PL
Wykorzystanie powłok jadalnych jest jednym z nowoczesnych rozwiązań technologicznych, pozwalającym na ograniczenie niekorzystnych zmian podczas przechowywania produktów spożywczych. Celem pracy było określenie wpływu powłoki jadalnej wytworzonej na bazie pullulanu, izolatu białka sojowego oraz kwasu stearynowego na zmiany mikrobiologiczne w mięsie wołowym. Próbki mięsa wołowego o masie 10 g pokryte i niepokryte powłoką przechowywano przez 7 dni w warunkach chłodniczych. Bezpośrednio po naniesieniu powłoki (czas „0”) oraz 3 i 7 dniach przechowywania oznaczano ogólną liczbę bakterii: tlenowych mezofilnych, z grupy coli, enterokoków, psychrotrofowych, bakterii kwasu mlekowego oraz drożdży i pleśni. Zastosowanie powłoki jadalnej najskuteczniej zahamowało wzrost liczby bakterii tlenowych mezofilnych, LAB, enterokoków i psychrofilnych, redukując ich liczbę o 1 cykl logarytmiczny w porównaniu z próbkami kontrolnymi (bez powłoki). Stopień zahamowania wzrostu badanych grup drobnoustrojów był jednak zbyt niski, aby można ją było stosować w przypadku surowca mięsnego.
EN
The main objective of food packaging is to preserve its freshness and microbial quality for a long period of time. In the meat industry, due to the nature of the product, the type of packaging and packing methods are chosen according barrier against adverse factors. The use of edible coatings is one of the modern technology that allows for the reduction of adverse changes during storage of food products. Edible coatings and fi lms are thin layers made of a single component or multicomponent mixtures which aim is the prevention or reduction biochemical, physicochemical and biological responsible for the spoilage of the product during its storage. The aim of the study was to determine the effect of edible coatings prepared on the basis of pullulan, soy protein isolate, and stearic acid on the microbiological changes occurring in bovine meat during the seven days refrigeration storage. The research material was beef purchased at one of the city’s supermarkets. Pullulan was prepared by the batch culture of Aureobasidium pullulans white mutant B-1. The strain used in the study came from the collection of the Department of Biotechnology and Food Microbiology, Warsaw School of Live Sciences. For the preparation of coatings stearic acid and soy protein isolate SUPRO 595 were used. Beef samples of 10 g weight were coated with an edible coating by immersing in a solution of the emulsion and drying in a laminar fl ow of sterile air at a temperature of 24°C. In parallel control samples without the coating were prepared. The meat samples coated and uncoated edible coating were stored for 7 days under refrigeration (4–6°C). Immediately after application of the coating (time “0”) and after 3 and 7 days of storage destignation for total number of mesophilic aerobic microorganisms, coliforms, enterococci, psychrotrophic bacteria, lactic acid bacteria and yeasts and molds were performed. It has been found that the method for applying the edible coating did not affect the reduce the initial number of microorganisms signifi cantly. There was no presence of mold in the tested samples of beef. During the storing the number of microorganisms identifi ed in the samples increased, however, in the samples coated with an edible coating it was signifi cantly lower. The use of edible coatings effi ciently inhibited the growth of mesophilic aerobic bacteria, LAB, enterococci and psychrotrophic bacteria. Their number, compared with uncoated samples was reduced by 1 log cycle. The same limitation of the number of yeast after 7 days of storage in the coated samples was observed. The degree of inhibition of growth of the tested groups of microorganisms was too low, so it can be used for raw meat.