| Fermented sausage is a kind of meat products,the meat will be divided into a certain size,and mixed with sugar,salt and other materials together,and then inoculated with natural or artificial starter cultures.A series of physical and chemical reactions occurred during the fermentation period,which gives a unique flavor to the fermented sausage products.The fermented sausage has a high nutritional value and delicious taste,and it is popular with consumers.At the same time,the fermented sausage has the characteristics of low water activity,low p H and a certain amount of salt.In addition,the preservation period of the fermented sausage is long,and it is easy to eat so that it can be widely popular in the world.Fermented sausage is usually made of pork,and the rabbit meat which has the reputation of "meat in the prime" is also suitable.Rabbit meat has a "four high and four low" nutritional value(such as high protein,high lysine,high lecithin,high digestibility,low fat,low cholesterol,low uric acid,low calorie).Fermented sausage made of rabbit meat is more nutritious and suitable for all ages of people.According to different processing methods,fermented sausages can be divided into dry sausage,semi-dried sausage and non-dry sausage.And they can also be divided into low-acid fermented sausages and high-acid fermented sausages according to the degree of fermentation.Yet,sometimes they can be divided into Sichuan sausages and Cantonese sausages based onits flavor.In this experiment,the raw material of fermented sausage is rabbit meat and inoculated with microbial starters.Although fermented sausages have many advantages,they still have a lot of problems during processing,such as their long fermentation cycle,undesired microbes during fermentation,high fat content and other issues.Therefore,it is very important to optimize the formulation and fermentation processing conditions.The quality of fermented sausage is affected by many factors duringprocessing,such as the type of starters,inoculation amount,fermentation temperature,fermentation time and so on.Unreasonable processing conditions will destroy the nutritional value of rabbit meat and fermented sausage taste,affecting consumers’ desire to buy.Therefore,it is of great significance to study the process optimization of rabbit meat sausage.In order to increase rabbit meat products and broaden the consumption of rabbit meat,this paper mainly studied the selection of two kinds of bacteria from five kinds of bacteria as the startercultures,and optimized the rabbit fermented sausage by single factor test and response surface optimization design,and then studied the quality changes of sausage during storage.The main conclusions are as follows:1.Screening of strains,Lactobacillus plantarum 102 and Lactococcus lactis were excluded from the Lactobacillus plantarum NO.07,Lactobacillus casei,Pediococcus pentosaceus22227,Lactococcus lactis and Lactobacillus casei by antagonistic test.Then,Lactobacillus plantarum PMO and pentoseococcus 22227 were determined as suitable mixed fermenting microorganism by salt tolerance test and nitrite resistance test.2.We can conclude that the growth of Lactobacillus plantarum PMO and pentoseococcus 22227 is well by salt tolerance test when thecontent of salt is about 2-3%.This is in line with the requirements for the addition of salt in fermented sausages.3.Through the single factor test,we can initially determine the best fermentation conditions: 2% inoculation amount,fermentation temperature of 25℃,fermentation time of 24 h.4.Through the response surface optimization test,we can determine the best processing conditions are inoculation 1.5%,fermentation temperature of 24 ℃,fermentation time of 21 h.Compared with the process parameters,the relative error between the actual value and the predicted value of the pH andSensory scores is below 2%,indicating that the optimization is reliable and can provide reference for the standardized production of fermented sausage.5.With the prolongation of storage time,there were significant differences in the sensory scores of the fermented sausages under the two storage conditions.The sensory quality of sausages stored at room temperature decreased with the increase of storage time,while the changes in sausage under cold storage are slower,the latter is more suitable for storage of fermented sausage.The nitrite values of the fermented sausage under the two storage conditions were all lower than the national standard of 30mg/kg.6.With the increase of storage time,the pH value of fermented sausage showed a tendency to decrease first and then increaseunder the two storage methods.Andthe pH value change of the sausages stored at room temperature is more significant.7.The TBARS values stored at room temperature and cold temperature were 0.556mg/kg and 0.458 mg / kg,respectively,which were less than 1.0mg/kg.When the storage time was 60 days,the TVB-N values of the fermented sausages stored at room temperature and refrigerated in cold temperature were 22.48mg/100 g and 14.39mg/100 g,respectively,which were lower than the safety standard.8.The number of lactic acid bacteria and the total number of bacteria in the sausages under the condition of room temperature storage showed a tendency to rise first and then decreased,while the number of colonies and the total number of bacteria in the sausages under cold storage were maintained at a relatively balanced state.And the approximate number of Escherichia coli in the two storage conditions was lower than 3MPN/g. |
