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This study is aimed to investigate the effect of microbial Lipase enzymes in different concentration of 10,30 and 50 ppm and ckecking it effect on bugget`s quality. Physicochemical characteristics of bread such as moisture, volume, texture tough, color and intuitive traits are evaluated. The results revealed that there aren`t  any remarkable differences in smell, volume, taste, crust color, shape coordination, crack and rupture and exterior characteristics between experiments and control experiment in intuitive evaluation (P>0.5). Bread produced in 10,30 ppm values of  Lipase enzyme have more prominence  in  characteristics like inner texture , crust quality, improving the ability to br chewed, proper perforation of the texture than control experiment, but using 10 ppm Lipase showed the most prominence in receiving overall intuitive characteristics. According to the results of texture examinations, using10,30ppm concentrations lipase  is better than 50 ppm lipase. Bread produced with 10ppm lipase showed the maximum volume and best crumb color, and 30 ppm lipase enzyme the best crust color of the all, and it has the maximum moisture between experiments and it was a remarkable difference among all experiments (P<0.5).  

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Bakery products, like many processed foods, are subjected to the physical, chemical and microbiological spoilage. Mold growth is a problem that limits the shelf life of high and intermediate- moisture bakery products .Water activity is a physical property that has a direct implication for microbiological safety of food. Foods with lower water activities are quite shelf life since they contain small a mount of water available for microorganisms to use for growth. In this research, effects of polyols (Glycerin, Sorbitol, Propylene glycol), invert and glucose syrup on the quality of batter and cake were evaluated. Polyols, invert and glucose syrup at five levels (1, 2, 3, 4 and 5%) were considered as variable treatments. The results showed that, cakes containing with propylene glycol had higher specific volume of batter, less height of cake and higher moisture of cake (P<0.05). Propylene glycol and glycerol were significant different in decreasing water activity other than sorbitol, invert and glucose syrup (P<0.05). Cakes containing propylene glycol and glycerol were more than sorbitol shelf life, invert and glucose syrup. Samples of cakes containing invert had the lowest pH (P<0.05). Thus, the polyols can be used to increase the quality and shelf life of cake.