Effect of chitosan and alginate edible coating incorporated with lauric arginate on chicken meat quality

Abstract

1- Effect of chitosan (2%), alginate (2%) edible coating or their incorporation with lauric arginate (2%( on the bacterial quality of chicken drumsticks There were significant (P < 0.05) reduction of APC, psychrotrophs, S. aureus and Enterobacteriacae counts in chitosan and alginate coated chicken drumsticks as compared with the control untreated samples. However, the higher reduction rate for bacterial counts was observed in chitosan coated samples as compared with alginate coated samples. It was also clear that temperature of coats application has an essential role in decreasing the bacterial counts. Where, it was observed that all investigated bacterial counts especially APC, psychrotrophs and S. aureus at 0 time of examination and along the freezing storage and the Enterobacteriacae at the 3rd month of freezing storage were significantly (P < 0.05) decreased in control untreated samples at temperature 50 ºC (C50) as compared with control untreated samples at temperature 25 ºC (C25). However, the significant (P < 0.05) reduction of APC in chitosan coated samples at temperature 50 (CH50) in the 2nd and the 3rd month of freezing storage were recorded as compared with chitosan coated samples at temperature 25 ºC (CH25). Interestingly, incorporation of LAE into chitosan or alginate coats at temperature 25 ºC and 50 ºC (M25 and M50) significantly (P < 0.05) decrease the bacterial counts of coated samples when compared with those coated with chitosan only at temperature 25 ºC and 50 ºC (CH25 and CH50) or alginate only at temperature 25 ºC and 50 ºC (Alg25 and Alg50). Based on the achieved results it was found that lauric arginate could enhance the antibacterial efficacy of chitosan and alginate coats.

2- Effect of chitosan (2%), alginate (2%) edible coating or their incorporation with lauric arginate (2%( on the deterioration criteria of chicken drumsticks pH is a decisive factor for determining the suitability of raw meat for manufacturing good quality products. Moreover, the measurement of pH, TVBN and TBA value is described a simple reliable and appropriate methods for detection of meat quality. Determination of TBA has been found to be a good indicator for lipid oxidation in meat and meat products. Spoilage in poultry meat caused by auto-oxidation and is evaluated by measuring the malonaldehyde (MDA) content, which is a secondary product of lipid oxidation. Among the chemical indicators of spoilage, TBA assay is commonly used to estimate the oxidative rancidity of meats and other fat containing food products; more specifically, this assay measures the quantity of malonaldehyde, which is an oxidative breakdown product formed mainly from peroxidized polyunsaturated fatty acids. Lipid peroxidation leads to low quality, rancidity and accumulation of potentially toxic substances in foods. TBA value was related to the oxidation in meat products also, some microorganisms can degrade the fat by either lipase hydrolysis enzyme or oxidation by oxidize enzyme which can yield rancidity. Oxidative rancidity was occurred at TBA more than 0.9 mg %.