الفهرس 
cover englishOnly 14 pages are availabe for public view
 |  | from | 112 |  |  |
| | | from | 112 | | |
Abstract
Chitosan is a natural bioactive polysaccharide, derived from the deacetylation of chitin with intrinsic antimicrobial activity and can be recognized as a natural alternative to synthesized antimicrobial for extending perishable food shelf life. For exploring the effect of chitosan and lactic acid and their combination on extending the shelf life of chicken breast fillets at refrigerator storage and decontamination of Salmonella Typhimurium and E.coli,chicken breast fillets were treated with chitosan 0.5% ,chitosan 1% , chitosan 2% and lactic acid 1% solutions beside their combination and stored at 4 o C. Treated samples were examined for sensory attributes, deterioration criteria and bacterial load at regular intervals. Samples treated with chitosan 0.5% didn’t significantly (P<0.05) differ from the control, meanwhile treated samples withchitosan 1%, 2% , lactic acid 1% and combination between chitosan 2% and Lactic acid 1% extended chicken fillet shelf life by three days more than the control. Although using of lactic acid 1% reduce the fillet bacterial load as chitosan 2% treated samples, however the sensory properties of treated samples with chitosan 2% were significantly higher than lactic acid 1%treated samples, as lactic acid 1% were showing significant reduction in their sensory attributes.Combination lactic acid 1% and chitosan 2% were nearly showing same results.Chitosan 0.5% or 1% nearly had no effect on reduction of Salmonella, but chitosan 2%, lactic acid 1% and combination of them reduced Salmonella count by about 1.5 log cfu/g. Chitosan 0.5% nearly had no effect on reduction of E. coli, but chitosan 2%, lactic acid 1% and combination of them reduced E. coli count by about 1 to1.5 log cfu/g.