【作者】 万娟；

【导师】 张慜；

【作者基本信息】 江南大学 ， 农产品加工及贮藏工程， 2012， 硕士

【摘要】 我国淡水鱼资源丰富,其高蛋白低脂肪,是优质蛋白质来源之一,但是淡水鱼加工业普遍存在着工业化程度低的缺点,造成了淡水鱼资源的巨大浪费。目前,对淡水鱼的研究主要集中在干燥、加工、风味以及品质控制等方面。本文研究以新鲜草鱼为原料加工休闲卤鱼粒的技术,充分利用了草鱼资源,并且对企业经济效益的增加具有重要的意义。本文研究了草鱼卤鱼粒制品的加工工艺及贮藏期间的品质变化,为草鱼卤鱼粒制品的加工生产提供理论和实践指导。为了研究草鱼的腌制过程及其对风味的影响。以新鲜草鱼为原料,从加盐量、腌制时间和腌制温度三方面来优化腌制工艺,得到最佳工艺参数为:加盐量10.89%、腌制温度9.23℃、腌制时为18.12 h。考察不同的风干时间对草鱼的风味影响,风干时间为6 d时,共检测出27种风味物质,风味物质中含量最高的是己醛,其含量为24.82%,其次是异戊酯,其含量为15.81%。风干时间为12 d时,共检测出48种风味风味物质,风味物质中含量最高是己醛,其含量为31.74%;其次是辛烷,其含量为15.28%。为了研究草鱼的干燥过程以及脱水过程中各部分水分的变化情况。采用低场核磁共振技术考察了新鲜鱼肉以及腌制和热风干燥处理的草鱼鱼肉的各部分水分的变化情况。在腌制干燥过程中,主要失去的是构造水。干燥的过程是一个逐层烘干的过程,弛豫时间较长的自由度较高的水分会先发生蒸发,之后再发生弛豫时间较短的自由度较低的水分的蒸发。比较热风干燥和真空微波干燥对草鱼片的干燥特性和品质影响,真空微波干燥能够提高干燥效率,并且鱼片的品质也优于热风干燥的鱼片。真空微波干燥的鱼片亮度值较大,而热风干燥的鱼片亮度值较小、黄度值较大。真空干燥鱼片的复水性要优于热风干燥的样品。为了研究草鱼干的加工工艺,主要从鱼干的脱盐、加工、风味以及产品品质的提高四个方面进行研究。研究草鱼干的脱盐过程,在水温30℃、水料比为10:1时脱盐180 min内达到平衡,脱盐时间较短,鱼体质构保全较好,脱盐结束鱼干可直接用于加工,无需再添加盐。油炸卤鱼粒的最佳加工工艺参数:油炸温度为170℃、油炸时间为4 min、鸡精用量为0.4%以及黄酒用量为1.5%。使用该工艺生产的卤鱼粒制品质构紧密、风味突出。卤鱼粒风味研究中共检出48种挥发性风味物质,其中主要风味物质是柠檬烯、2-甲基丁醛、己醛。采用涂膜法降低油炸卤鱼粒的含油率,比较了羧甲基纤维素钠,海藻酸钠,琼脂对含油率和色泽的影响,一般可使含油率降低10%-17%。海藻酸钠降低含油率的效果最好。为了研究油炸卤鱼粒在贮藏期间的贮藏特性,通过常温和高温贮藏实验,考察贮藏期间酸价(AV)和过氧化值(POV)的变化,实验发现贮藏期间AV值升高较快,因此对于高温高压杀菌的油炸卤鱼粒而言,酸价是影响货架期的主要因素。考察了茶多酚的抗氧化性,添加0.3 g/kg的茶多酚能使贮藏末期鱼粒的过氧化值降低23.09%,酸价降低26.47%。更多还原

【Abstract】 China water area is abundant in freshwater fishes. The freshwater fish is a good source of high quality protein, but the industrialization level was low in production scale, which leading a tremendous waste of freshwater fish resource. Currently, the study of freshwater fish mainly concentrated in the drying, processing, flavor and quality control.This thesis was focused on developing processing methods on grass carp relating leisure food, the storage characteristics and processing methods studied in this thesis may bring economic benefits for the enterprises and provide theoretical basis and production guidance in industry and scientific research.In order to study the curing process of grass carp and its impact on the flavor. Optimizing the salting processing treatment from the content of salt, curing time and curing temperature with fresh grass carp. The optimal condition is as follows: the ratio of salt 10.89%, time18.12 h and temperrture 9.23℃. The flavor components of grass crap under different salting time were studied. Totally 27 kinds of flavor components were detected on the sixth day. Hexanal was the highest level with a content of 24.82%. Isopentyl ester was in a lower level with a content of 15.81%. 48 kinds of flavor components were detected on the twelfth day. Hexanal was the highest level with a content of 31.74%. Octane was at second level with a content of 15.28%.In order to study the drying process of the grass carp and changes in various parts of the water during the dewatering process.The LF-NMR was used to determine the moisture changes in fresh grass carps fillets、salted and dried fillets. During the curing and drying process, the main weight loss was the immobilized water. The drying process was a layer by layer drying. The free water evaporated first and then the immobilized water and the constitutional water began evaporated. Comparing the drying characteristics and the quality of dried samples of hot air drying and vacuum microwave drying, final results indicated that vacuum microwave drying was more efficient and leading to a better quality in dried grass crap fillets. The vacuum microwave dried fillets were lighter in color whereas the hot air dried grass carp fillets were darker and more yellow. For rehydration, rehydration rate constants of the salted grass carp fillets from vacuum microwave drying were significantly higher than those from hot air drying.In order to study processing technology of the grass carp, the study mainly from four aspects: desalination、processing, flavor and product quality.The desalination was studied. The optimal condition of desalination is: water temperature 30℃, the ratio of water to fish fillets10:1, desalting time 180min. The desalted fish fillets could directly for process without adding salt. The optimal condition of frying is: frying temperture 170℃, frying time4min, seasoning time 3 min and dosage of millet wine 1.5%. 48 kinds of flavor components were detected in fried grass carp. The main flavor components of fried grass crap were limonene, 2- methylbutyryl aldehyde and hexanal. Three kinds of coating materials (CMC, sodium alginate and agar) were used to the decrease of oil content in fried grass carp. 10%-15% oil was reduced after coating pretreatment. Oil content can significantly be reduced with Sodium alginate coating. In order to study storage characteristics of product during storage. The changes of AV and POV were determined under room temperature and through high temperature storage experiment. The AV level rised quicker than that of POV. For the high temperature and high pressure sterilized fried grass carp, the AV was the key factor in shelf life. 0.3 g/kg tea polyphenol added could reduce the AV for 26.47% and the POV for 23.09%.更多还原