EFFECT OF ROSEMARY ESSENTIAL OIL ON THE QUALITY OF PORK BURGERS

摘要

The aim of this study was to determine the effect of rosemary essential oil (EO) on the quality of burgers manufactured without synthetic additives and stored under retail display conditions. For that 3 batches of pork burgers (minced to 5 mm and 2% salt) were prepared: the control group C, R_1 (0.05% EO), and R_2 (0.4% EO). The patties were packed with modified atmosphere (70%O_2: 20%CO_2: 10% N_2) and stored for a maximum of 9 days at 4°C. Meat spoilage was determined by measuring colour, microbiological analysis (total viable, total psycrophiles and mould and yeast counts, log u.f.c/g), and sensory analysis was carried out evaluating visual and odour attributes (Rancid Odour and Meat Colour) through descriptive analysis with 10 trained panellists. Analysis was performed at 0, 3, 6 and 9 days. L, a~*, b~* values showed that EO (R_1 and R_2) increased colour stability. From day 3 of storage had higher a~* values (P<0.05), which implies less pigment oxidation and a better appearance. This was contrasted with the sensory analysis. Independently of the dosage used, a positive effect of rosemary was found on meat colour and rancid odour. Regarding the antimicrobial effect of EO, significant differences from C group and R_1-R_2, was observed in mesophiles and psycrophiles during all the storage. The use of EO of rosemary improves the quality of burgers due to the fact that this delays the oxidation of fat and colour and microbiological spoilage, improving the appearance of the meat.