Which Method Is Better for Preserving Meat and Cheese: Coating Propolis on The Packaging Material or Spraying Directly onto The Food?

Abstract

This study was carried out to determine whether it is better to spray a preservative coating of propolis on the food packaging material or directly onto meat and cheddar cheese. To test this, the surfaces of a vacuum bag (Polyamide/Polyethylene-PA/PE), some stretch film (Low Density Polyethylene- LDPE) and a ziploc bag (Oriented Polypropylene-OPP) and food samples were coated by spraying them with a propolis-ethyl acetate (PEA) solution. Moreover, a propolis-propylene glycol (PPG) solution was sprayed directly on the food surfaces (cheese and meat) to study the shelf life of these products without packaging. Meat and cheddar cheese placed in packages and covered with a PPG solution were stored at 4°C for 30 and 45 days, respectively. The predominant phenolic compound in the propolis used in the study was caffeic acid phenethyl ester (CAPE) at a level of 27.523,4 μg g-1, and the lowest amount of phenolic acid was epigallocatechin gallate at 287.53 μg g-1. At the end of the storage period, the Enterobacteriaceae count of the meat sample stored in propolis sprayed vacuum packaging decreased by 1.01 log CFU g-1 (p˂0.05) compared to the control, and achieved the best result. It was concluded that the PPG solution applied onto the meat did not adhere well to it and the solution could not achieve its antimicrobial effect. At the end of the storage period, while the cheddar cheese sample kept in a propolis-treated vacuum bag had the lowest TMAB count for 21 days (p˂0.05), PPG directly sprayed on cheddar cheese had the lowest TMAB count at the end of storage with 6.64 log CFU g-1 (p˂0.05). The PPG solution was able to adhere to the surface of the cheddar cheese and propolis was able to show its antimicrobial activity. In addition, the LAB (MRS) value for the cheddar cheese sample stored in propolis-treated vacuum packaging decreased by 0.60 log CFU g-1 (p˂0.05) compared to the control and achieved the best result. Microbiological analysis showed that propolis coating in vacuum packaging improved the microbiological quality of the meat and the cheddar cheese.