【作者】 何雪莲；

【导师】 李从发；

【作者基本信息】 华南热带农业大学 ， 农产品加工及贮藏工程， 2007， 硕士

【摘要】 本文开展了以罗非鱼加工下脚料为原料发酵生产鱼露的研究。为了提高菌种对罗非鱼下脚料进行水解的适应性,首先研究了用鱼糜浆代替部分麦芽汁而制备鱼糜液体曲的方法。探讨了制曲温度、时间、米曲霉种子液添加量对鱼糜液体制曲的影响,通过测定液体曲的蛋白酶活力确定制曲最佳条件。结果表明,温度为40℃,时间为12h,种子液添加量4%为最佳制曲条件,此时,鱼糜液体曲的蛋白酶活力为1270u/mL。然后对鱼露发酵工艺进行了研究,探讨了加盐量、加水量、大豆固体曲量、鱼糜液体曲和原料处理方式对鱼糜发酵过程中氨基酸态氮变化的影响,确定了加曲发酵最佳工艺。结果表明:罗非鱼鱼糜与1.5倍(w/w)水混合打浆,经加热煮沸10min后,加入20%大豆固体曲、15%鱼糜液体曲和9%食盐,于40℃静置发酵12d时得到发酵醪氨基酸态氮为0.77g/100mL,总氮含量为1.69g/100mL。在鱼糜液体曲与大豆曲发酵相结合的基础上,于后熟阶段加入鲁氏酵母(As2.180)和球拟酵母(As2.202)进行再酵以增强酱油质量和风味,生产品质优良的营养鱼酱油。结果表明:采用后熟温度30℃,酵母混合液量10% (As2.180∶As2.202=1∶1),酱醪盐度12%,后熟12d的工艺条件,可生产出优质的鱼酱油产品,其氨基氮、有机酸等营养成分均高于国家标准,且有显著的鲜香味(乙醇4.670 g/L)。最后以腥味成分三甲胺含量和氨基氮损失率为指标,比较了活性炭、β-糊精、酒糟液、海藻糖等对罗非鱼下脚料发酵鱼露脱腥的效果,并通过正交试验得出各自最佳的脱腥条件。经过比较发现,使用活性炭、海藻糖和酒糟液的效果优于β-环糊精。采用海藻糖和活性炭联合脱腥处理,即先添加海藻糖6%在40℃下处理120min,再添活性炭0.5%在35℃处理20min,得到的醪液基本上无腥味,且氨基氮损失率较低(7.24%)。在添加大豆曲量20%、液体曲15%、加盐量9%、发酵温度40℃的条件下,废弃物发酵得到的鱼露,氨基酸态氮为0.77g/100mL,总氮为1.69g/100mL、比重为1.12、酸度为1.99g/100mL;产品的得率约为517mL鱼露/kg原料。最后的感官分析结果表明,该鱼露风味好、色泽深。更多还原

【Abstract】 Fish sauce fermentation technology was studied with wastes after sliced tilapia production to enhance the utilization ratio of fish protein.First,liquid koji was made with Aspergillus oryzae (As3.951) from tilapia waste. the optimum conditions were as follows:tilapia waste was firstly mixed with water in the ratio of 1:1,and heated to 80℃for 5 min and cooled ,and then inculated with 4% liquid starter of Asp. oryzae (As3.951) ,and kept at 40℃for 12h, the protease activity of liquid koji-making obtained was 1270u/mL.Then ,fish sauce fermentation technology was investigated , and the optimal fermentation conditions were as follows: tilapia waste was added with 150% water and blended, boiled for 10min, and then added with 20% soya koji, 15% liquid koji and 9% salt. Then the mixture was fermented at 40℃for 12d.The fermented product contained 0.77g/100mL aimino nitrogen, and 1.69g/100mL total nitrogen.To enhance the flavor ,the mixed culture of Saccharomyces rouxii As2.180 and Torulopsis globosa As2.202(As2.180∶As2.202=1∶1) was added by 10% to the product obtained above ,and re fermented at 12% of salt content for another 12d ,and the flavor was improved with the alcohol content being 4.670g/L.The deodorizing effects ofβ-cyclodextrin,active carbon ,the fucose and on fish sauce were compared using the lose of dissociative amino-nitrogen and the content of TMA as assay parameters. The results indicated that the fishy smell removing effect of active carbon,the fucose were better thanβ-cyclodextrin .Through the L9 (33) orthogonal test, the best deodorizing effect was obtained when fish sauce was treated with 6% fucose at 40℃f or 120 min followed by adding 0.5% active carbon at 35℃for 20 min.After the experiments, the fish sauce is rich in tasty amino acid ,and the fish odour was removed .更多还原