【作者】 张进杰；

【导师】 叶兴乾；

【作者基本信息】 浙江大学 ， 食品科学， 2012， 博士

【摘要】 腌制腊鱼风味独特,耐贮藏,在我国南方的饮食文化中有着重要地位。风味和食用安全性是腌制水产制品的重要品质,加工、贮藏和烹饪均对水产制品的风味和食用安全性有重要影响。本文以草鱼为实验原料,针对产业的需求,系统分析了传统腌制腊鱼的加工工艺,贮藏方法和烹饪方式对腊鱼风味和食用品质的关系,为传统腌制腊鱼的品质控制提供理论基础。主要结果如下：1.腊鱼腌制工艺优化以腌制后草鱼肉盐溶性蛋白含量、氯化钠含量、盐卤蛋白质含量为指标,通过单因素试验及响应面分析法,研究不同腌制条件(时间、温度、加盐量)对草鱼肉品质的影响,并建立感官评定结果与测定指标的数学模型,优化干腌工艺条件。结果表明：1)鱼肉中氯化钠的含量及盐卤中蛋白质含量与腌制时间、温度和加盐量正相关；腌制时间、温度对鱼肉盐溶性蛋白含量有一定影响。2)采用响应面分析法建立感官评定与腌制条件的数学模型,曲面回归方程拟合性好。对感官评定结果的影响：加盐量>腌制温度>腌制时间。3)通过响应面交互作用分析与优化,最佳腌制条件：腌制温度为9.29℃,腌制时间6.02 d,加盐量11.70%,所得腊鱼的感官评分值与模型预测值基本相符。结论：腌制时间和腌制温度对腊鱼感官评定结果的影响极显著,草鱼干腌的最适加盐量为1：9。2.腊鱼干制成熟工艺优化研究了日晒干制(RS),5℃低温干制(DW5),15℃低温干制(DW15),15℃罨蒸干制(YZ15)和45℃热风干制(RF45)5种不同腊鱼干制方式的制作时间,对腊鱼制品的营养成分、蛋白质降解相关产物(游离氨基酸、生物胺、硝酸盐、亚硝酸盐、TVB-N)和食用感官品质的影响。5种不同腊鱼干制方法的工艺时间长短顺序为：RF45<DW15<DW5<YZ15<RS,YZ15工艺时间约为RS的一半。干制显著性地提高鱼肉中蛋白、油脂和灰分的含量,但各干制方式的成熟腊鱼之间的基本营养成分无显著性差异；SDS图谱显示RS和YZ15腊鱼中蛋白质降解程度最大,显著性提高腊鱼中呈味氨基酸含量。干制导致鱼肉的蛋白质和油脂发生降解氧化,促进腊鱼肉中生物胺、硝酸盐含量、亚硝酸盐含量和TVB-N值的升高,综合对比各干制腊鱼食用安全性及食用感官品质,以YZ15所得腊鱼安全性和食用感官品质为最佳。15℃罨蒸干制方式既提高了传统腊鱼制作效率,也提高了腊鱼食用安全性和改善了腊鱼的感官品质。3.香辛料对腊鱼油脂的抗氧化作用研究了在腊鱼腌制及干制成熟过程中添加花椒对腊鱼油脂的抗氧化作用。添加2%(W/W)的花椒粉末,对腌制和干制成熟的腊鱼基本营养成分无显著影响,能显著性抑制草鱼油脂中极性油脂比例、游离脂肪酸含量、油脂过氧化值和油脂TBA值的升高(P<0.05);添加花椒抑制了油脂中饱和脂肪酸含量的升高,单不饱和脂肪酸和多不饱和脂肪酸含量的降低,显著性地抑制了鱼块油脂中DHA和EPA含量的降低(P<0.05),起到了保持腊鱼油脂质量的作用。4.香辛料和蔗糖对腊鱼中蛋白质降解产物和感官品质的影响研究了添加花椒和蔗糖的腌制工艺对腊鱼品质的影响。对比考察了腊鱼A(食盐10%)、腊鱼B(食盐10%+花椒2%)和腊鱼C(食盐10%+花椒2%+蔗糖1%)制作过程中腊鱼肉中微生物(总菌落数和总乳酸菌落数)、水溶性氮类物质(WSN)、非蛋白氮类物质(NPN)、游离氨基酸(FAA)和总挥发性盐基氮(TVB-N),以及感官评定分值的变化。花椒对腊鱼中总菌落数有一定的抑制作用,而对乳酸菌无明显影响,抑制蛋白降解产物TVB-N的生成；而蔗糖的添加能显著性降低腊鱼的pH值,增加腊鱼中乳酸菌菌落数,促进蛋白质降解,提高腊鱼中WSN、NPN和FAA含量；花椒和蔗糖的组合添加能显著性地改善腊鱼的色泽、气味和鲜味。同时添加花椒、蔗糖和食盐腌制而成的腊鱼C具有最优的感官品质。5.腊鱼制作过程中非挥发性呈味成分分析研究了腊鱼制作过程中非挥发性风味成分(糖、琥珀酸、无机盐、游离氨基酸和5’-单磷酸呈味核苷酸),及添加蔗糖腌制对腊鱼中非挥发性呈味成分的作用。腊鱼A(添加蔗糖腌制)中检测出核糖、葡萄糖、果糖、磷酸化核糖、磷酸化葡萄糖和蔗糖6种糖；腊鱼B(未添加蔗糖腌制)中只检测出葡萄糖、果糖、磷酸化核糖和磷酸化葡萄糖4种糖；腊鱼A中总糖含量约为腊鱼B的8倍。腊鱼中各糖含量和琥珀酸含量均小于其阈值。NaCl对腊鱼的咸味起到绝对性的贡献作用。干制成熟过程中腊鱼肉中游离氨基酸含量显著性增加,成熟腊鱼A和腊鱼B分别有11种和9种游离氨基酸含量均大于阈值。腊鱼制作过程中腊鱼肉中5’-单磷酸种类有所变化,在成熟腊鱼A中检测出6种5’-单磷酸核苷酸(5’AMP、5’-CMP、5’-GMP、5’-IMP、5’UMP、5’-XMP),腊鱼B中检测出5种5’-单磷酸核苷酸(5’-AMP、5’-CMP、5’GMP、5’-IMP、5’-UMP)；腊鱼A中呈味核苷酸含量和总5’-单磷酸核苷酸含量均大于腊鱼B(呈味核苷酸含量：27.94 mg/100 g>15.40 mg/100 g；总5’-单磷酸核苷酸：31.97 mg/100g>19.42 mg/100 g)；经氨基酸与核苷酸的呈味协同作用计算分析,干制成熟过程是腊鱼鲜味生成的主要阶段。腊鱼A最终产品的EUC约为腊鱼B的两倍,由此说明,在腊鱼制作过程中,添加蔗糖有利于腊鱼呈鲜味的提升。6.不同保鲜方法对腊鱼中微生物和生物胺作用的比较研究研究了托盘保鲜膜空气包装(C)、真空包装(VP),气调包装(MAP,100%CO2),壳聚糖涂膜包装(CF)对4°C冷藏过程中腊鱼中微生物、生物胺和三甲胺(TMA)的含量变化。在冷藏过程中所有处理样品的pH值呈逐渐下降趋势,而总菌落数、总乳酸菌落数、总生物胺含量和三甲胺(TMA-N)含量均呈逐渐上升的趋势。VP、MAP和CF对腊鱼中总菌落数和主要优势菌---乳酸菌均有显著性抑制作用,以CF对腊鱼中总菌落数的抑制效果最优。在C和VP样品的贮藏后期有大肠杆菌检出。成熟腊鱼中只检测出组胺、腐胺、尸胺、酪胺亚精胺和精胺6种生物胺,而在贮藏后期腊鱼中检测到9种生物胺。组胺、腐胺、尸胺、酪胺为腊鱼中主要生物胺成分,VP、MAP和CF对腊鱼贮藏过程中生物胺形成的抑制作用具存在显著性差异,只有亚精胺和精胺在4种包装处理腊鱼贮藏过程中无显著性变化；100%CO2MAP和CF对苯乙胺和色胺的生成具有显著性抑制作用;以组胺含量安全性衡量,腊鱼在4°C冷藏条件下,C、VP、MAP和CF处理包装的腊鱼保质期分别为60d,120 d,150d和180d。7.不同烹饪方法对腊鱼游离氨基酸和生物胺含量的影响研究了不同烹饪方法对两种腊鱼(A：加1%糖腌制；B：不加糖腌制)食用品质,糖、游离氨基酸和生物胺的影响。蒸制9 min和微波烹制4min时,腊鱼食用的感官品质均分别为最佳。加热烹饪处理导致美拉德反应的发生,糖(还原糖、磷酸化糖和蔗糖)、游离氨基酸和生物胺含量发生不同程度的变化。蒸制处理(9 min)导致腊鱼A和腊鱼B中总糖含量分别下降113.58和7.52 mg/100g DW；微波烹饪处理(4 min)导致腊鱼A和腊鱼B中总糖含量分别下降186.12和75.26 mg/100g DW；蒸制处理导致游离氨基酸含量升高,而微波处理导致游离氨基酸含量显著性降低。蒸制处理在一定程度上有降低腊鱼A中总生物胺的作用(-2.24%),却使腊鱼B中总生物胺含量稍有增加(2.06%)；微波处理使添加蔗糖腌制的腊鱼A的腐胺、尸胺和组胺含量分别降低28.26%、43.81%和59.16%,总生物胺含量下降46.49%；未添加蔗糖腌制的腊鱼B的腐胺、尸胺和组胺含量分别降低15.51%、20.63%和21.15%,总生物胺含量下降18.85%。添加蔗糖腌制腊鱼,和采取的微波烹饪方式可显著性的降低最终食用腊鱼中生物胺含量。更多还原

【Abstract】 Layu is the traditional name for the dry-cured grass carp (Ctenopharyngodon idellus) produced in China. It is popular not only for its special chewiness and flavor but also longer shelf life. The flavour and edible safety is the main quality of fermented fish food. While the processing, preservation and cooking methods determined those properties. In this study provided the theory basis for processing, preservation and cooking of Layu products. The main results were as follows:1. Optimization of dry-salting technology for grass carp using response surface analysisUsing the content of sodium chloride and salt-soluble protein in Grass carp (Ctenpharyngodon idellus) muscle and the protein content in brine as indexes, the effect of different salting condition (time, temperature and concentration of brine) on the quality of grass carp muscle was studied by single factor test and response surface analysis method. A multiple regression model was set up between the results of sensory evaluation and determined indexes in different dry-salting condition. The results showed as follows:1) There were positive correlation between dry-salting factors such as time, temperature and concentration of brine and the content of sodium chloride in grass carp muscle as well as the protein content in brine. The dry-salting time and temperature affected the content of salt-soluble protein in grass carp meat.2) The model set up by response surface method showed regression equation fit well with experimental data, and the content of sodium chloride extremely significantly affects the sensory evaluation, followed by fermentation temperature and time.3) When the dry-salting time 6.02 days, temperatue 9.29℃and the concentration of sodium chloride added to 11.70%, Grass carp dried was best with the sensory evaluation. The results were basically correspond to model prediction.2. The influence of different drying processes on quality of LayuFive different processing conditions, Sun-drying (5-15℃, RS), low-temperature drying (5℃, DW5), low-temperature drying (15℃, DW15), combination drying (15℃, YZ15) and hot-air drying (45℃, RF45) of curing Layu were studied, and the nutrient components, physicochemical properties and sensory quality of Layu were compared. The order of the different processing time listed here:RF45< DW15< DW5< YZ15< RS. Results showed that drying process had a great effect on the nutrient components and they increased the contents of protein, oil and ash, but there is none significant differences between different drying processes. The drying process has significant influence on the dydrolysis of proteins in fish meat showed by SDS-PAGE result, and significantly increased the content of free amino acids in the Layu products, especially RS and YZ15 drying methods. The content of biogenic amines, Nitrite, Nitrates and the TVB-N value increased in the drying process. Overall, sensory evaluation showed that the combionation dried Layu was more acceptable than the other drying methods products. Based on the safety and sensory quality comprehensive evaluation, the combination drying process is the best choice for drying the curing Layu.3. Effect of spice on the lipid oxidation and fatty acid composition of Layu during processingThe Chinese traditional dry-cured grass carp fish (Layu) was processed without (A) and with (B,2%, W/W) spice, Zamthoxylum Bungeanum Maxim, and the lipid oxidation and fatty acid composition of Layu was investigated. All treatments reduced the moisture contents and increased the relative ratio of protein, lipids and ash, and there were non differences between A and B. Zanthoxylum Bungeanum Maxim has the ability of delaying oxidation of oils. The oil of Layu A had a higher peroxide value, thiobarbituric acid (TBA) index value, the content of polar lipids and free fatty acids than Layu B during the manufacturing process. Layu B had a higher content of DHA and EPA than Layu B. Zanthoxylum Bungeanum Maxim can improve the quality of Layu.4. Spice-sucrose treatments to improving the quality of LayuThe effect of spice and sucrose treatments on the quality of Layu was evaluated. Under the same processing, the Grass carp meat was marinate with A (salt), B (salt and Zanthoxylum Bungeanum Maxim), and C (salt, Zanthoxylum Bungeanum Maxim and sucrose). The pH value of C significantly lower than those of A and B. B and C affected the population of total viable counts, but C had a higher population of lactic acid count than those of A and B. Zanthoxylum Bungeanum Maxim has the ability of decreased the formation of total volatile basic nitrogen (TVB-N) in Layu. Sucrose increased the content of water soluble nitrogen (WSN), none protein nitrogen (NPN) and free amino acids (FAAs) of Layu. Zanthoxylum Bungeanum Maxim combined with sucrose improve the color, flavor and umami taste of Layu. Product C has the best quality.5. Effect of sucrose on the non-volatile taste compounds of LayuThe non-volatile taste active compounds, including soluble sugars, succinic acid, free amino acids and flavour 5’-nucleotides in the meat of Layu (A:fermented with 1% sucrose; B:fermented without sucrose), and the effect of sucrose on the non-volatile taste active compounds in Layu during processing were analyzed. Higher levels of sugars, NaCl and free amino acids, and lower flavour 5’-nucleotide were detected in the final products when compared to the fresh fish. In the presence of sucrose, Layu A had higher levels of sugars (461.88±57.83 mg/100g), free amino acids (2566.86±87.21 mg/100g) and 5’-nucleotide (31.97±3.32 mg/100 g) than those of Layu B (57.20±9.85 mg/100g,2401.19±85.27 mg/100g, and 19.42±1.87 mg/100 g, respectively) after ageing. In Layu A,6 sugars (ribose, glucose, fructose, phosphorylated ribose, phosphorylated glucose and sucrose) were detected while only 4 sugars (glucose, fructose, phosphorylated ribose and phosphorylated glucose) were detected in Layu B. There were 11 and 9 free amino acids were of higher taste active values (TAV) greater than on in Layu A and Layu B, respectively. The total content of sugars in aged Layu A is eight times higher than that of Layu B after ageing. The total content of flavour 5’-nucleotide in Layu A (27.94±3.05 mg/100 g) is higher than that of Layu B (15.40±1.87 mg/100 g). As the TAVs of soluble sugars, succinic acid and flavour 5’-nucleotide were lower than one, those compounds are likely to have insignificant impact on the taste of Layu. For the effect of sucrose on the content of free amino acids and flavour 5’-nucleotide in the production of Layu, the equivalent umami concentration (EUC) of Layu A (5.085 g MSG/100g meat) is higher than that of Layu B (2.645 g MSG/100g meat), which meant that the umami taste of the Layu meat was very intense, and the addition of sucrose in the processing, can increase the taste of Layu, especially the umami.6. Biogenic amines in Layu preserved by four different packing methodsA study was carried out to determine the effect of vacuum packed (VP) and modified atmosphere (MAP) (100% CO2) packing, chitosan film (CF) and cling film (C) wrapping on the microorganisms, and the formation of biogenic amines and trimethylamine (TMA) during storage of Layu at 4℃. The pH value generally decreased, while the Total viable counts, Lactic acid bacteria, biogenic amine and TMA contents generally increased in all treatments with increasing storage period. Lactic acid bacteria were the predominant flora in Layu, and some enterobacteriaceae were detected in samples C and VP. Levels of putrescine, cadaverine, histamine, tyramine, spermidine and spermine in Layu samples were found to be in the range of 0-52.53 mg/kg whose concentration changed little for a period of 20 days at 4℃. While 9 biogenic amines were detected at the end of storage, and putrescine, cadaverine, histamine and tyramine were the main biogenic amines. The treatments of VP. MAP and CF possess different inhibitory effect on the increasing of biogenic amines. The content of spermiidine and spermine isn’t influenced by the treatments, while MAP and CF can significantly suppressed the increasing of phenylethylamine and tryptamine. The treatment of C, VP, MAP and CF extended the shelf life of Layu to 60 d,120 d,150 d and 180 d, respectively.7. Effect of two cooking methods on sensory quality and biogemic amines of LayuThe effect of cooking methods on the content of sugars, free amino acids and biogemic amines were studied in two kinds of Layu (Layu A:fermented with 1% sucrose; Layu B: fermented without sucrose). The optimum cooking time for Steaming and microwaving is 9 min and 4 min, respectively, getting the best sensory quality. Thermal processes indurced the different changes in sugars (reducing sugars, phosphorylated reducing sugars and sucrose), free amino acids and biogenic amines through Maillard reaction. After the application of steaming 9 min, the content of total sugars in Layu A and Layu B were decreased respectively by 113.58 and 7.52 mg/100g DW. After the application of steaming 9 min, the content of total sugars in Layu A and Layu B were decreased respectively by 186.12 and 75.26 mg/100g DW. The treatment of steaming increased the content of free amino acids, while microwaving decreased that in Layu A and Layu B. Steaming treatment decreased the content of total biogenic amines in Layu A (-2.24%), while increased a little amount of that in Layu B (2.06%). Microwaving treatment decreased the content of putrescine, cadaverine and histamine 28.26%,43.81% and 59.16%, respectively in Layu A; by 15.51%,20.63% and 21.15% in Layu B. Microwaving treatment decreased the total biogenic amines by 46.49% and 18.85% in Layu A and Layu B, respectively. It could be concluded that Layu fermented with sucrose, and with the microwaving method can decrease the content of biogenic amine to the minimum.更多还原