The Cold-Air Drying Dynamic Characteristics And Drying Process Optimization Of Dry-Cured Ducks

Traditional process controled for dry-cured ducks which was by natural drying, the cycle of production was long, microorganism was difficult to control. Hot-air drying was often used in industry production, but its high temperature would easily cause the loss of thermal sensitive composition in aquatic products.Low temperature and humidity of the cold-air drying environment could delay and weaken the food corruption which caused by microorganism, enzyme and non enzyme action process, thus effectively maintained product quality. The article based on dry-cured ducks as raw materials using the response surface method optimization control its cold-air drying process,and studied the properties of the cold-air drying dynamics in the manufacturing process of control, through the scanning electron microscope, nutritional, sensory indicators, acid value and peroxide value compared the cold-air drying products and hot-air drying products, got the result of the advantage of cold-air drying pruducts.1.In order to studied the effect temperature, humidity, wind speed on the quality of dry-cured ducks in drying process, considered the effect of three factors on the sensory quality of abalone by single factor experiments. The results showed that:the effect order of three factors on the quality of dry-cured ducks in the experimental range:humidity>temperature>wind speed, as well as the effect of three factors on sensory score increased at first then decreased and show a down parabola.In order to got the best drying technology of drying process, optimized operating parameters of cold-air drying of dry-cured ducks established a quadratic regression orthogonal rotational combing design which optimize technology taking temperature(x1), humidity (X2) and wind (X3) for dry conditions. With sensory score as index, finally obtained the second response surface regression model: and the optimum drying temperature:10.9℃, humidity:75.8%, wind speed:2.4775m/s.2. In order to controled product quality and characterize dynamics characteristic, studied dynamic characteristics of dry-cured ducks and diffusion rate of internal moisture of dry-cured ducks by diffusion coefficients during drying process. The results showed that:effective diffusion coefficients were in1.37×10-10m2/s-2.48×10-10m2/s range, at the temperture was from5℃-25℃.3. To illustrated the superiority of the cold air drying dry-cured ducks, made drying treatment for dry-cured ducks in cold-air drying, hot-air drying and finished chemical comparison parameters under the condition of different operating parameters.(1)By color analysised, showed that the cold-air drying dry-cured ducks which the L value was larger than the hot-air drying.(2) By electron microscopy (sem) under different magnification scans could examine the cold-air drying lined up of muscle control, the space between the fibers was clearly visible, muscle fibers and endomysium closed together. Hot air drying of muscle fibers began to control lateral contraction, muscle fibers and endomysium gap.Weakened muscle wire structure.Then myofibril produced deformation, fracture and collapse phenomenon.Showed the hot air drying the chewiness of control was lower than the cold air drying control.(3)By the sensory score of two drying methods, showed product by cold air drying haved the highest score and was the best for shape, smell, taste.(4)The peroxide value and acide value of the cold air drying dry-cured ducks was lower than the hot air drying products. The results showed that dry-cured ducks was the best by cold air drying.