Effect of lactic acid and acetic acid on the quality of local meat

Abstract

Effect of lactic acid and acetic acid spray on the quality and shelf-life extension of fresh beef stored at 4oC was investigated. Lactic and acetic acid were sprayed over the meat at various concentrations of 0 (control), 2% lactic acid (L.A.), 4% L.A, 2% acetic acid (A.A.) and 4% A.A. then stored at 4oC for 9 days. Samples were examined in the fresh state (0 day), prior to spay. At specified time (30 min,1, 3, 5, 7 and 9 days) ,samples were analyzed for microbial counts, sensorial properties, pH and total volatile basic nitrogen(TVB-N). Bacterial groups count to indicate effectiveness of treatments included aerobic plate counts (APCs), Psychrophilic counts (PTCs) and total coliform counts(TCCs).Since the beginning of the experiment, the inhibitory effect of lactic acid and acetic acid has been observed. Lactic and acetic acid reduced the microbial counts immediately after the treatment and retarded microbial growth during storage. At first day of display, APCs were reduced by 1.5 to 3 log cycles, log psychrophilic counts were consistently reduced and log coliform counts were reduced to undetectable levels in acid treated groups. The inhibitory effect on bacterial growth was pronounced when the concentration of lactic acetic and lactic acids increased. Acetic and lactic acid treatments improved the microbiological and physicochemical qualities of meat and consequently prolongs their shelf life. Shelf-life of acid treated samples from microbial quality standpoints was 7 -9 days according to treatment used against 3 days in untreated samples. Four percent lactic acid treatments appeared to be more effective in delaying the microbial growth however; meat sample could not keep their color and odor. Comparing the effects of the two acids treatments, lactic acid was found to be more effective in both concentrations used. Lactic acid sprayed samples, particularly with 2%, showed the greater acceptability than did those sprayed with acetic acid throughout the storage days. From microbial and visual quality standpoints, meat sample sprayed with 2% seemed to be more acceptable regarding meat color and bacterial numbers with proper hygiene and handling procedures could provide safer meat with good qualityandto ensure safe public health.