Improvement Of Technology, Quality Of Smoked Chicken Duirng Cold Wind Drying Process And The Prediction Of Its Shelf Life

Smoked chicken is one of the most famous traditional dried poultry meat products inChina. It is popular for its nice appearance, brown color, close texture, and good taste which isduo to unique formula and traditional techniques. The key link of the process is cold winddrying technology. But traditional drying technology has a lot of problems. There is no certainprocess parameters, and it is greatly influenced by the local and regional climatic conditions.Usually smoked chicken is produced just in winter which takes nearly20days. The quality ofthe products is unstable and unsafe. As a result, this paper optimized the cold wind dryingtechnology of smoked chicken and improved the quality of the products by biologicalfermentation method in order to supply reference parameters for industrial production andmarket promotion.Firstly, to solve the problems of the traditional drying technology, the cold wind dryingprocess of smoked chicken is optimized in this paper. The effects of time, temperature,relative humidity and wind speed on the quality of smoked chicken were studied. The singlefactor experiments were used with indicators of moisture content, NPN, TVBN, TBARS andthe sensory scores. Then an orthogonal experiment was carried out with the orthogonal valueof NPN, TBARS and sensory scores. The results showed that the optimized cold wind dryingprocess of smoked chicken was as follows: temperature18℃, relative humidity65%, windspeed4m/s, time72h. The results of Pearson correlation analysis showed a positivecorrelation between the sensory scores and NPN, TBARS values. Besides, the textural, colorand flavor substances of the best smoked chicken products were checked.Secondly, on the basis of the optimized cold drying process, L.p and P.p wereinoculated into the chicken. Physiological and biochemical characteristics of these two kindsof lactic acid bacteria were determined. Results of the study showed that L.p and P.p had goodability to produce acid at18℃, good tolerance to salt and nitrite and had the ability to breakdown proteins whereas no ability to break down fat and no antagonistic which suggested thatthe two kinds of lactobacillus were suitable for the experiment.Moreover, the effects of L.p and P.p on the quality of smoked chicken were studied. Tochoose proper inoculation concentration and ratio of L.p and P.p, some characteristicindicators including water content, pH, NPN, TVBN, TBARS, NaNO₂, hardness, chewiness,springiness and color were determined. Then the best ratio of L.p and P.p was identified as5:2and the best concentration was identified as3%1×109cfu/mL by a central compositeexperiment. The quality of the products with and without bacteria was also compared. Theresults showed that the quality of the product with bacteria was better than that of the productwithout bacteria.Finally, to make sure the shelf life of the two products at4℃, the changes of colonycount, TVBN, TBARS and pH were studied, also coliforms and pathogenic bacteria weretested. Logistic and Gompertz models were established to measure the growth ofmicroorganisms in the two products. The results showed that: the most important indicatorwhich determines the two products’ shelf life was microbial; the shelf life of the products without bacteria and with bacteria was84days and121days respectively at4℃.