Evaluate the effect of using a whey protein membrane loaded with zinc nanoparticles, lactoferrin and neptomycin on microbial growth in laboratory-made soft white cheese

Abstract

The study was conducted in the laboratories of the Department of Food Sciences-College of Agriculture and in the animal house of the College of Veterinary Medicine at Tikrit University for the period from 1/2/2021 to 15/3/2022. The aim of this study was to manufacture edible whey protein membranes with concentrations of 10%, as well as fortify these membranes with zinc nanoparticles, natamycin, and lactoferrin with different concentrations and interactions. The treatments were as follows: T1:control, T2:membrane, T3:0.25 mg nanoparticle zinc and membrane, T4:60 mg lactoferrin and membrane, T5:50 mg bacteriocin and membrane, T6:0.25 mg nanoparticle zinc, 60 mg lactoferrin and T7:0.25 mg zinc. Nano and 50 mg bacteriocin and T8:60 mg lactoferrin and 50 mg bacteriocin and T9:0.25 mg nano zinc and 60 mg lactoferrin and 50 mg bacteriocin. Soft cheese was made from cow’s milk and coated with whey proteins, and the cheese was stored for 21 days at 5±2 °C. The microbial evaluation of cheese coated with whey protein films and fortified showed that the number of bacteria on the first day of storage ranged between 4.13-5.65 Log/g compared with the control samples 1T and 2T at 7.59 and 6.63 Log/g, respectively. At the end of the storage period, treatment 9T was the lowest in terms of growth, reaching 4.26 Log/g, as well as for lipolytic bacteria, as treatment 9T was the least in terms of growth, reaching 1.12 Log/g. This applies to protein-analyzing bacteria, as the results showed that the transaction 9T was the least in terms of growth, reaching 1.64 Log/g