【作者】 郭黎洋；

【导师】 章建浩；

【作者基本信息】 南京农业大学 ， 食品科学， 2008， 硕士

【摘要】 羊肉是国际上每一个国家都食用的畜肉之一,但其特别的气味（“膻”味）而影响部分消费者的可接纳性。火腿是我国主要的传统腌腊肉制品,因其色、香、味而著称于世。在我国新疆牧区,民间有将羊肉腌制后风干成熟形成风干羊肉的习惯。本课题试图采用传统火腿的腌制风干成熟工艺,探索改善山羊腿气味和风味的工艺方法,为采用新工艺新技术开发具有特色风味的羊腿新产品提供理论和技术基础。具体研究内容和结果如下:1.山羊腿干腌发酵成熟工艺研究:参照金华火腿现代工艺技术进行山羊腿腌制、发酵、成熟实验,研究其成熟工艺参数及在腌制、发酵过程中山羊腿的理化指标、质构变化及感官评定情况。结果表明:随着加工过程的进行,水分含量经历了从高到低的变化,在风干成熟60天的时候达到48.86%;NaCl含量则随着加工进程逐步增高,风干成熟60天时为9.41%;pH值在加工过程中无显著变化（6.13～6.40）。感官评定结果:经过脱水风干成熟60天,产品风味质感得分较高。综合理化指标分析及感官评定结果,山羊腿腌制、发酵、成熟合理的工艺参数为:腌制20天（8℃;RH 60%）;风干发酵20天（15-20℃;RH 80%）;成熟20天（20-30℃;RH 90%）。2.山羊腿在工艺过程中脂质分解氧化研究:分析工艺过程6个工艺点样品股二头肌中游离脂肪酸（FFA）的变化及硫代巴比妥酸值（TBARS）、双烯值等氧化指标,研究其与温度、湿度等工艺条件的相关性,结果表明:总脂肪和甘油三酯含量随加工时间逐渐升高（P＜0.05）,而磷脂呈下降趋势（P＞0.05）;游离脂肪酸总量（∑FFA）和不饱和脂肪酸（UFA）在发酵20天达到最高（459.25和229.89mg/g脂质）,随后随着温度的上升而下降。FFA含量前四位分别是油酸、棕榈酸、亚油酸和硬脂酸,其中亚油酸是脂类物质中最重要的形成风味化合物的脂类成分。TBARS在风干发酵20天达到最高值0.28μgTEP·g^-1后下降且与温度呈正相关,表明温度会促进脂质分解氧化,当温度升高到一定程度时脂质氧化的初级产物会进一步氧化为风味物质;双烯值基本呈上升趋势,与含盐量和温度呈正相关（R²=0.907和R²=0.603）,表明一定的盐含量有利于脂质氧化的发生。3.山羊腿在工艺过程中风味物质变化研究:采用固相微萃取（SPME）和GC-MS方法鉴定分析工艺过程中山羊腿的风味物质,并采用主成分分析方法研究其风味特征。结果表明:工艺过程中共检测出风味物质71种（醇类10种;醛类17种;酸类3种;酮类7种;烃类13种）,其中醛类物质含量最高,占风味物质,总量的37.46%。第一主成分（Axis1）主要由直链醛（已醛、戊醛、庚醛、辛醛和壬醛）组成,解释了股二头肌风味成分总方差的56.79%;第二主成分（Axis2）主要由5种醇（己醇、戊醇、乙醇、3-甲基-1-丁醇、2-甲基-1-丁醇）,2种酸（3-甲基丁酸、乙酸）组成,解释了股二头肌风味成分总方差的24.31%。2,2-二甲基戊烷、3,3-二甲基庚烷、4,5-二甲基壬烷,这一类的支链化合物可能和羊肉的特征性风味（4-甲基辛酸和4-甲基壬酸）相关。更多还原

【Abstract】 Goat meat is one of the widely consumed meats in the world.However,its special odour causes low consumption.Dry-cured ham,as one of the most significant of air-drying and ripening animal products,is well-known because of its flavor,color and taste.In Xinjiang province of China,local people have the custom of curing the goat meat and keeping it outdoor for air-drying and ripening to special products.The aim of this paper is to explore the new processing technology for improving sensory qualities of goat legs by using dry-curing and ageing process of traditional ham in order to provide a theory and technology basis for developing goat meat new products.The contents and results of each chapter are as follows:1) Studies on curing and air-drying and ripening processing technique and parameters of goat legsThe process of curing and ageing of goat legs was researched by using Jinhua ham traditional process.The index of chemical compounds,textures,and sensory evaluation were analyzed during processing.Results showed that:water content decreased and the content of sodium chloride increased with the processing,which were 48.86%and 9.41%at 60 days of aging respectively,pH values in goat legs was no significant changes（P＞0.05）. The hardness,adhesiveness,springiness and chewiness of goat legs increased,cohesiveness and resilience decreased with the processing.The results of sensory evaluation:the score of flavor content,flavor intensity and overall appreciation arrived highest at the process point of 20 days ageing.The process parameters of curing and air-drying and ripening for goat legs were salting-curing 20 days（8℃,60%RH）,air-drying stages 20 days（15-20℃;80% RH）;ageing stages 20 days（20-30℃;90%RH）.2) Lipolysis and lipid oxidation in goat legs during processingThe lipid oxidation and lipolysis in biceps femoris muscle were studied by analyzing FFA,TBARS,conjugated diene value at 6 processing and the relationship with temperature and relative humidity.Results showed that:the total of lipids content and triacylglycerol increased（P＜0.05） during the processing,but phospholipids decreased.FFA content increased before the stages of 20days air-drying,arrived highest at ageing for 20 days （459.25mg/g lipid）.Palmitic acid,linoleic acid,Linoleic and stearic acid were main free fatty acid in goat legs,and linoleic was the main free fatty acid forming the flavor of goat legs by oxidation.TBA values increased before the stages of 20days air-drying arrived 0.28μgTEP·g^-1 at the stages of 20days drying and ageing,then decreased;conjugated diene value increased totally.Salt content and temperature had significantly influence on lipid oxidation（R²=0.907 and 0.603 respectively）.3) Studies on the flavor compounds of goat legs during processingFlavor compounds in biceps femoris of goat legs were extracted and identified by solid phase microextraction（SPME） GC/MS system during processing.Main flavor compounds was identified in the analysis method of CPA（principal component analysis）. The flavor compounds in final products of goat legs was clustered in the following chemical families:alkanes and alkenes,aromatic hydrocarbons,alcohols,aldehydes, ketones,carboxylic acids,esters,oxygenous heterocycle compounds,nitrogenous compounds,sulphur compounds,chloride compounds,amides and terpenes.The content of aldehydes is highest,accounting for 37.46%of total flavor compounds.The first principal component of the flavor compounds in final products was a group dominated by aldehydes （2-methyl-,Butanal;3-methyl-,Butanal;3-methyl-,Butenal;Decanal;Heptanal;Hexanal; Nonanal）.The second principal component was a group mainly dominated by alcohols （Ethyl alcohol;1-Octen-3-ol;1-Penten-3-ol;Heptanol;Hexanol;2-ethyl-,Hexanol） and acids（3-methyl-Pentanoic acid;Acetic acid;2-methyl-,Butanoic acid）,which had a multiple origins.The two first principal components of biceps femoris explained 56.79% and 24.31%of the total variance of the flavors respectively.The branched compounds such as 4,5-dimethyl,Nonane;2,2-dimethyl,Pentane;3,3-dimethyl,Heptane could have the connection with the goat special odour（4-methyl octanoic acid and 4-methyl nonanoic acid）.更多还原