| Abstract
This study aimed to prepare an inhibitory edible coating for Gouda cheese based on
whey protein containing lactoperoxidase system (LPOS) and Bunium persicum essential
oil (EO) in order to control postpasteurization contamination. Using a full factorial
design, the effects of LPOS and EO on microbiological characteristics and chemical
indices of manufactured Gouda cheeses were evaluated during 90 days of storage
time. Listeria, lactic acid bacteria, Enterobacter, Escherichia, and Pseudomonas species
were considered as potential pathogenic and spoilage indicators of produced Gouda
cheese samples. Chemical properties of cheeses were assessed using the free fatty
acid, peroxide value, and thiobarbituric acid experiments. The results showed that
bacteria counts remained constant in cheese samples coated with EO and also EO–
LPOS. However, the survival of gram-positive
lactic acid bacteria and Enterobacter
spp. was more pronounced in LPOS-based
coating. The most effective treatments on
oxidation stability parameters in cheese samples were EO-and
EO–LPOS coatings.
By the addition of B. persicum EO and LPOS, further inhibition of the lipid oxidation
of the cheese samples was achieved. Lipolysis, as a result of lipid degradation, was
more pronounced in the control, whey-coated,
and whey–LPOS-coated
samples in
comparison with whey–EO-and
whey–EO–LPOS-coated
samples during the final
days of storage time. These results indicate that antibacterial, lipid oxidation, and
oxygen barrier properties of the coatings were developed by the addition of B. persicum
EO and LPOS. |