Study on Application of Red Yeast Rice in Fermented Sausage
|School||Henan Agricultural University|
|Course||Agricultural Products Processing and Storage|
|Keywords||fermented sausages process optimization quality physicochemical properties red yeast rice|
In order to reduce the amount of nitrite in the processing of fermented sausages and explore the effects of different amounts on the quality of product, the effects of maturing temperature, maturing relative humidity and red yeast rice addition on sensory quality of fermented sausages were investigated by quadric regression orthogonal rotary design and response surface methodology, and the processing technology parameters were optimized. The physicochemical changes of fermented sausages in the optimized condition during fermentation and ripening process were also investigated. Furthermore, the effects of different levels of red yeast rice on the sensory, microorganism and physicochemical properties of fermented sausages during storage time were studied. The main results and conclusions are as follows:The three factors affected the sensory quality of fermented sausages in the following order, maturing temperature>maturing relative humidity >red yeast rice addition. The optimum technological conditions were: maturing temperature 14℃, maturing relative humidity 76% and red yeast rice addition 1.6g/kg. The sensory evaluation score of salami was 32 under the optimum conditions, which was consistent with the predicted value.In the first three days of fermentation,the fermented sausages pH dropped rapidly to below 5.2 and minimized on day 14,with the value of 4.81.Afterwards,a slight increase in pH was observed which might have been due to amines and ammonia production.The final pH value of the fermented sausage was 4.89.There was almost no change in moisture content during fermentation.And the dehydration rate increased by day 14.However, after day 14,it degreased slowly.The sugar consumption mainly took place in fermentation and early stages of ripening process, then changed slowly. The final total nitrogen and free fatty acid contents increased with the increase of fermentation and ripening time. However, based on the accumulation of dry matter in fermented sausages, the final total nitrogen and free fatty acid contents were not significantly different during fermentation and ripening time (p<0.05).In the aspect of sensory quality, the overall sensory score of fermented sausage with 0.5%, 1% and 1.5% red yeast rice (R1, R2 and R3)can be accepted when these products stored at 4℃for 14 days. Color and taste are predominant influence factor in thecomprehensive sensory. At the same time, the sausages with 1% red yeast rice (R2) had the best overall acceptance by the panelists.In the aspect of microorganism, the total plate count, mold count and anaerobic bacteria count of fermented sausages with different levels of red yeast rice (R1, R2 and R3) were significantly higher than that of A and C, and the values were from7.19 to 7.91logCFU/g, 6.98 to 8.05logCFU/g and 7.22 to 7.99logCFU/g, individually, during cold storage (4℃).In the aspect of physicochemical properties, the water activity of all treatments was not significantly different with storage time and the values were from 0.94 to 0.95. A slower decline rate of pH for all treatment of fermented sausages with red yeast rice can be found. Additionally, with addition of red yeast rice, the degrading rate of nitrite can be slowed down in this study. In the color, the a value of all sausages with red yeast rice were higher than that of A and C (p<0.05). Moreover, a value of R1 were closed to C. The L value of A and C were higher than that of all sausages with red yeast rice. The b value of all sausages with red yeast rice was significantly different with storage time, and the products with 0.5% red yeast rice (R1) had the similar b value as C with storage time. T-VBN value of all treatments with different levels of red yeast rice were higher than that of the A and C during storage, and T-VBN value increased with red yeast rice levels. TBA value of all treatments with different levels of red yeast rice were higher than that of the A and C at 7 day during storage, and TBA value also increased with red yeast rice levels. However, during day 7 to14,it all degreased.Based on the safety of fermented sausages,we should do more research in order to analyze and verify the feasibility.