Development Of Brown Flavor Fermented Milk And Main Flavor Analysis

With the improvement of living standard and health awareness,the demand for fermented milk increases gradually.Brown flavor fermented milk is an innovative product of dairy products,and it has become a major feature of the fermented milk market due to its unique processing technology,flavor and nutrition.However,the investigation of consumers shows that the quality of brown flavor fermented milk on the market is uneven,there are few studies on brown flavor fermented milk now.Therefore,the main factors affecting the sensory quality of brown flavor fermented milk were studied in this experiment,and the main flavor was analyzed,so as to obtain a brown flavor fermented milk with appropriate flavor,which could meet the market demand and standardized production.Main results were as follows:(1)The single factor experiment determined that the appropriate browning time was 5 hours,the sucrose addition was 3%,and the inoculation quantity was 2%.The sensory quality of brown flavor fermented milk was significantly different with different glucose addition,browning temperature,skim milk powder addition,and fermentation time(p<0.05).(2)Three appropriate levels were selected for orthogonal test based on the influencing factors glucose addition,browning temperature,skim milk powder addition and fermentation time,and sensory score was considered as the evaluation index.The best solution was as follows: glucose was 6%,browning temperature was 98?,skim milk powder was 1.25%,fermentation time was 13 hours.(3)The optimal addition range of stabilizer was confirmed by the single test,it was that AGAR was 0.01%-0.10%,sodium carboxymethyl cellulose was 0.05%-0.15%,and high methoxy pectin was 0.01%-0.05%.Orthogonal test was conducted at three levels within the optimal addition range of the three stabilizers,and apparent viscosity was used as the evaluation index.The optimal stabilizers compounding scheme was obtained as follows: AGAR addition was 0.05%,sodium carboxymethyl cellulose addition was 0.10%,high methoxy pectin addition was 0.01%,total addition of stabilizers was 0.16%,and apparent viscosity up to 658.39 m Pa·s.(4)The brown flavor fermented milk developed in this experiment was compared with four similar products on the market by means of electronic tongue technology.The results showed that the sourness was the most obvious difference,followed by saltiness and sweetness,and bitterness was close to zero.Principal component analysis showed that the cumulative contribution rate of the first and second principal components reached 92.43%,which could reflect the overall information of the sample.The sourness,umami and saltiness had higher loading in the first principal component,which indicated that these indexes were the most important ones to evaluate the flavor quality of brown flavor fermented milk.Sweetness and richness had higher loading in the second principal component,which indicated that the second principal component was related to sweetness and richness.(5)36 types of volatile compounds were detected by GC-MS,including 12 types of ester compounds with a relative content of 26.89%,9 types of hydrocarbon compounds with a relative content of 26.93%,7 types of acid compounds with a relative content of 13.60%,2 types of ketones with a relative content of 25.35%,2 types of alcohols with a relative content of 1.63%,and 4 types of heterocyclic compounds with a relative content of 5.60%.The results showed that the main olfactory components of fermented milk come from esters,hydrocarbons and ketones.