耐盐微生物对鳀鱼露风味形成的影响

研究了艉制鱼露中的耐盐微生物（耐盐乳酸菌M1、M2和耐盐产蛋白酶菌T1）对其发酵初期挥发性风味物质形成的影响。将从鱼露发酵液中分离出来的耐盐微生物经过扩大培养后添加到鱼盐混合物中进行鱼露发酵。在发酵初期,总酸、氨基酸态氮、总氮、非酶褐变指数等理化指标都明显优于未添加发酵剂的空自对照鱼露发酵液。用气相色谱-质谱联用（GC-MS）分析其挥发性风味物质。结果表明,鱼露初期发酵液中分离出来的耐盐乳酸菌M2、产蛋白酶菌T1对鱼露挥发性特征风味成分的形成,尤其是挥发性酸的形成有积极的贡献,而自然发酵的鱼露则很难在发酵初期产生特征挥发性风味物质。     

4种嗜盐古菌发酵的龙头鱼鱼露特性比较

以去除内脏的龙头鱼为原料,利用自行筛选的4种嗜盐古菌做发酵剂生产鱼露。通过测定发酵4.5个月后氨基酸态氮(AAN)、亚硝酸盐、总胺、总酸、挥发性盐基氮(TVB-N)、可溶性总氮(TSN)、组胺、游离氨基酸组成、挥发性风味物质含量变化,从4种嗜盐菌中挑选出更加适宜发酵鱼露的菌种。接种TBN4的鱼露在4种嗜盐古菌发酵的鱼露中氨基酸态氮、可溶性总氮含量、挥发性风味物质总量最高,游离氨基酸含量丰富,且组胺含量最低。而接种9738的鱼露氨基酸态氮含量最高,接种RO2-11的鱼露挥发性风味物质总量较高,组胺含量较低。     

鱼露中耐盐菌的分离鉴定及发酵性能比较

该研究从鱼露中筛选不同株耐盐菌进行菌种鉴定,并对其发酵性能进行研究。经筛选获得5株耐盐细菌,编号为JL-B、JL-C、JL-D、JL-E、JL-F,通过形态学和分子生物学鉴定菌株JT-F为表皮葡萄球菌,其余4株均为嗜盐四联球菌。经5株耐盐菌在蓝圆鲹鱼肉水解液中的发酵特性研究结果表明,5株耐盐菌发酵的鱼肉水解液pH值、总酸、菌落总数、氨基酸态氮（AAN）、挥发性盐基氮（TVBN）含量及感官评价均存在显著差异（P＜0.05）,而总可溶性氮（TSN）的含量并无显著差异（P＞0.05）,且均未检出5'-肌苷酸二钠（IMP）、5'-鸟苷酸二钠（GMP）及组胺。样品发酵60 d后感官评价结果表明,接种嗜盐四联球菌JL-B的鱼肉水解液的风味可接受度最高,酱香味及鲜味突出,发酵效果最好。其pH值最低,稳定在4.30左右,氨基态氮含量最大达到0.49 g/100 mL。     

耐盐微生物对鯷制鱼露风味形成的影响

研究了鯷制鱼露中的耐盐微生物(耐盐乳酸菌M1、M2和耐盐产蛋白酶菌T1)对其发酵初期挥发性风味物质形成的影响。将从鱼露发酵液中分离出来的耐盐微生物经过扩大培养后添加到鱼盐混合物中进行鱼露发酵。在发酵初期,总酸、氨基酸态氮、总氮、非酶褐变指数等理化指标都明显优于未添加发酵剂的空白对照鱼露发酵液。用气相色谱-质谱联用(GC-MS)分析其挥发性风味物质。结果表明,鱼露初期发酵液中分离出来的耐盐乳酸菌M2、产蛋白酶菌T1对鱼露挥发性特征风味成分的形成,尤其是挥发性酸的形成有积极的贡献,而自然发酵的鱼露则很难在发酵初期产生特征挥发性风味物质。     

罗非鱼加工下脚料速酿低盐优质鱼露的研究

文章针对传统鱼露含盐量高、发酵周期长这两个弊端进行了鱼露发酵工艺的优化.采用酶法及微生物发酵方法联用对罗非鱼加工下脚料进行低盐发酵,在实现低值废弃物高值化利用的同时大大缩短了鱼露发酵周期并改善了鱼露风味.首先对下脚料进行复合酶解,然后对米曲霉进行驯化后再对酶解液进行低盐发酵,以发酵液中氨基酸态氮,总酸含量等指标进行工艺的优化.最后通过响应面优化法确定了最佳发酵工艺为:在水解度为20%的基础上添加盐量10%,温度为32℃、种曲添加量为0.2%的条件下保温发酵9天.最后得到的发酵鱼露初品呈棕红色,澄清透明,风味良好;氨基酸态氮含量达到0.5462 g/dL,蛋白质利用率达到55.2%.     

Limosilactobacillus fermentum FSCBAD033控制带鱼加工下脚料发酵鱼露中生物胺含量研究

目的 控制带鱼加工下脚料低盐发酵鱼露中的生物胺含量。方法 以耐盐性高效生物胺降解乳酸菌Limosilactobacillus fermentum FSCBAD033为功能发酵剂控制带鱼加工下脚料发酵鱼露中的生物胺含量,并研究其对鱼露发酵过程中的pH值、NaCl含量、总可溶性氮(Total Soluble Nitrogen,TSN)含量、氨基酸态氮(Amino Acid Nitrogen,AAN)含量、挥发性盐基氮(Total Volatile Basic Nitrogen,TVB-N)含量以及发酵结束时感官风味的影响。结果 与Control组相比,接种L. fermentum FSCBAD033发酵剂对鱼露发酵过程中的NaCl含量影响不大(p>0.05),但可促进pH值下降以及TSN和AAN含量上升,并显著抑制TVB-N的产生(p<0.05)；显著降低发酵结束时鱼露中52.38%尸胺、40.21%组胺、45.44%酪胺、23.74%腐胺、52.67%苯乙胺和43.26%总生物胺(p<0.05),对含量较低的色胺、精胺和亚精胺影响不大；此外,接种L. fermentum FSCBAD033发酵剂可增强发酵结束时鱼露的鲜味和肉味,减弱氨味、腥味和臭味,整体提升鱼露感官风味。结论 L. fermentum FSCBAD033可作为带鱼加工下脚料低盐发酵的功能发酵剂,用于生产低盐、营养丰富、感官风味好且生物胺含量低的高品质鱼露产品。     

淡水鱼加工副产物低盐风味鱼露速酿工艺的优化

主要以淡水鱼加工副产物为原料,采用分段加盐法酿造低盐风味鱼露,探讨了时间、温度、加酶量、加曲量和初始pH对发酵过程中氨基酸态氮(AA-N)含量的影响,且在单因素的基础上采用正交试验对工艺进行优化。结果表明发酵工艺的最佳条件为:发酵温度50℃,加曲量20%,加酶量0.1%,初始pH 6.0;各个因素对氨基酸态氮(AA-N)的含量均有显著性影响,影响顺序为:加曲量初始pH发酵温度加酶量;在最佳发酵条件下鱼露中的氨基酸态氮含量为1.396g/dL。     

盐度和加曲量对罗非鱼片加工废弃物速酿鱼露的影响

对罗非鱼片加工废弃物速酿鱼露的发酵工艺进行了初步研究，从氨基酸态氮、总酸、TVBN、色度、感官5个指标分析了速酿鱼露在不同盐度（4，7，10，13g／dL）和不同加曲量（质量分数10％、15％、2S％、35%）下的发酵状况，综合各指标的影响确定适宜的速酿发酵条件为：7g／dL盐度和10％的加曲量，在此条件下的鱼露发酵液氨基酸态氮、总酸含量较高、腐败程度低，风味感官评价较好。     

低盐鱼露在保存中的性质变化

研究考察了盐分含量为15％的低盐鱼露在保存中的性质变化.结果发现,在保存中鱼露pH下降,挥发性盐基氮含量逐渐上升,但密封保存可以使它们的变化速度下降.在30℃保存下,密封使鱼露中的菌落总数(TVC)逐渐下降,未密封的鱼露,其TVC出现先上升后下降的趋势.在40℃下,鱼露中的TVC出现上升,未密封的鱼露出现最高值为640 cfu/mL,但低于国家标准(5000 cfu/mL).另一方面,在保存中鱼露的氨基酸态氮含量逐渐上升,颜色变深.结果表明,15％的低盐鱼露利用密封条件可以在30～40℃下保存.     

温度对加曲速酿低盐鱼露性质的影响

以蓝圆够为原料,添加酱油曲制备低盐鱼露,考察了恒温发酵温度和变温分段发酵对低盐鱼露性质的影响。在发酵过程中,20℃和40℃恒温发酵可以使酱醅pH稳定在5．2～5．5,但在30℃下经过90d发酵后酱醅的pH逐渐上升并接近6,导致鱼露的挥发性盐基氮（TVB—N）含量最多,表明加曲速酿鱼露的发酵不适合在30℃下进行。然而,20℃低温发酵鱼露中的氨基酸态氮（AA—N）和可溶性总氮（TS—N）的含量都较低,40℃发酵的鱼露含有一定的苦味。当利用先低温后高温分段发酵方式制备低盐鱼露时,不仅可以提高鱼露的AA—N和TS—N的含量,而且可以降低TVB—N含量。游离氨基酸组成分析和感官评价结果表明,分段发酵还可以改良加曲速酿鱼露的品质。     

鲫鱼蛋白酶解制取鱼露及其降胆固醇活性研究

以鲫鱼为原料,利用蛋白酶解技术制取富含多肽的酶解物,并以酶解物为基本原料制备调味品鱼露。通过对胆固醇胶束溶解度的抑制作用,研究其降胆固醇的活性。结果表明,最佳酶解条件为时间5.40h,加酶量109.67U/mL,温度40.23℃,此时胆固醇胶束溶解度抑制率为53.129±0.670%,与预测值54.617±0.240%相吻合。在此条件下,制得的鱼露风味佳、营养高,且具有较好的降胆固醇活性。     

CHARACTERIZATION OF A SALT-TOLERANT ACID PROTEASE PRODUCED BY BACILLUS MEGATERIUM KLP-98 AND ITS POTENTIAL AS A FERMENTATION STARTER FOR THE MANUFACTURE OF FISH SAUCE

A salt-tolerant acid protease was purified from the culture broth of Bacillus megaterium KLP-98 with a molecular weight of 64 kDa. K _m and k _cat values of the protease were 2.1 mg/mL and 6.1 s⁻¹ against azocasein as a substrate, respectively. The optimal temperature for protease activity was 60C but optimal stability temperature was below 40C. The optimal pH for protease activity was 5.5, and it was stable from pH 4.5 to 6.0. Relative activity of the protease was 73, 33, and 5% at 10, 20, and 30% NaCl concentrations, respectively. Among all the substrates tested, the best substrate for B. megaterium KLP-98 was azocasein followed by Z-Phe-Arg-NMec. The protease activity was strongly inhibited by N-ethylmaleimide and E-64. This protease was therefore presumed to be a salt-tolerant acid cysteine protease. The purified protease was applied to accelerate the fermentation of anchovy sauce, and the results indicated its potential as a fermentation starter.

PRACTICAL APPLICATIONS

The B. megaterium KLP-98 protease accelerated the fermentation of anchovy sauce and greatly improved its quality only during 2 days of fermentation, thus will decrease its production cost. Hence, fish or soy sauce industries can benefit from this protease as a fermentation accelerant.     

促酱醪发酵芽孢杆菌的筛选及应用

用酪素平板法从高盐稀态酱醪中筛选出56 株蛋白酶活性较好的菌株,牛津杯法复筛后制曲测定酶活性,得到淀粉酶活性最高的菌株CS1.11、蛋白酶活性最高的菌株CS1.13及纤维素酶活性最高的菌株CS1.17;16S rRNA序列测定结合形态学分析,CS1.11、CS1.13、CS1.17分别鉴定为贝莱斯芽孢杆菌（Bacillus velezensis）、甲基营养型芽孢杆菌（B. methylotrophicus）、枯草芽孢杆菌（B. subtilis）;分别将3 株实验菌与对照菌枯草芽孢杆菌CS1.03单独进行制曲后盐卤发酵,发现CS1.13发酵酱油氨态氮质量浓度最高,为5.12 g/L,CS1.11发酵酱油还原糖质量浓度最高,为27.20 g/L,与其酶活性结果一致,4 株菌对酱油总酸含量影响不大;顶空固相微萃取气相色谱-质谱联用内标法定性及定量分析发酵酱油发现,3 株实验菌与对照菌均具有产生吡嗪类物质及其前体乙偶姻和2,3-丁二醇的优势,且3 株实验菌优于对照菌;吡嗪类物质能赋予酱油良好的风味及健康因子,是芽孢杆菌酱油发酵的特征风味物质。筛选自高盐稀态酱醪的芽孢杆菌CS1.11、CS1.13、CS1.17有促酱醪发酵、丰富酱油风味、增进健康因子的潜力,具备良好的应用前景。     

淡水鱼加工下脚料速酿低盐鱼露的工艺研究

对利用淡水鱼加工下脚料制备低盐鱼露的速酿工艺进行研究。结果表明低盐淡水鱼露发酵最适条件为：加盐量8%、加酶量0.25%、温度45℃、固液比为1:0.75。制得的鱼露产品固形物含量19.43%,游离态含基酸氮含量0.73g/100ml。鱼露呈橙红色;透明,无悬浮物和沉淀物;具固有香味,无异臭味;口感咸鲜,入口滑爽。研究表明,在外加酶和保温的情况下实现了淡水鱼加工下脚料速酿低盐鱼露的目的。     

Improvement of Fish Sauce Quality by Strain CMC5‐3‐1: A Novel Species of Staphylococcus sp.

Staphylococcus sp. CMC5‐3‐1 and CMS5‐7‐5 isolated from fermented fish sauce at 3 to 7 mo, respectively, showed different characteristics on protein hydrolysis and volatile formation. These Gram‐positive cocci were able to grow in up to 15% NaCl with the optimum at 0.5% to 5% NaCl in tryptic soy broth. Based on ribosomal 16S rRNA gene sequences, Staphylococcus sp. CMC5‐3‐1 and CMS5‐7‐5 showed 99.0% similarity to that of Staphylococcus piscifermentans JCM 6057^T, but DNA–DNA relatedness was <30%, indicating that they were likely to be new species. DNA relatedness between these 2 strains was only 65%, suggesting that they also belonged to different species. The α‐amino group content of 6‐month‐old fish sauce inoculated with Staphylococcus sp. CMC5‐3‐1 was 740.5 mM, which was higher than that inoculated by the strain CMS5‐7‐5 (662.14 mM, P < 0.05). Histamine was not produced during fermentations with both strains. Fish sauce inoculated with Staphylococcus sp. CMC5‐3‐1 showed the highest content of total glutamic acid (P < 0.05). The major volatile compound detected in fish sauce inoculated with Staphylococcus sp. CMC5‐3‐1 was 2‐methypropanal, contributing to the desirable dark chocolate note. Staphylococcus sp. CMC5‐3‐1 could be applied as a starter culture to improve the umami and aroma of fish sauce.     

酶解-发酵法制备鱼鲜汁的工艺优化

本文以鲐鱼为原料,利用单因素和正交试验,优化了酶解-发酵法制备鱼鲜汁的工艺,并对其进行了理化指标和微生物检测,以及氨基酸和生物胺测定,从而对产品的营养性和安全性进行了分析。结果表明:原料采用中性蛋白酶/风味蛋白酶（1:2,w/w）,酶添加量800 U/g(w/w),固液比1:4(w/v),50 ℃下酶解6 h后,水解度为69.67%±0.47%;并在此条件下,加入米曲霉制作的豆粕曲（14%,w/w）,加食盐（9%,w/w）,40 ℃下恒温发酵21 d,此条件下所得的发酵液呈红褐色,具有鱼味调味品固有香气及味道,氨基酸态氮含量达0.81±0.02 g/100 mL。发酵液中鲜味氨基酸Asp和Glu,占比27.20%;必需氨基酸占比44.95%;组胺含量仅为13.35 mg/L。该发酵液可作为调配鱼露或其它海鲜调味品的基料,试验为鲐鱼的加工利用提供一条新的途径,具有较好的开发前景和市场预期。     

Acceleration of Thai fish sauce fermentation using proteinases and bacterial starter cultures

ABSTRACT:  A means to accelerate fish sauce fermentation without adversely affecting fish sauce quality was investigated. Starter cultures prepared from Virgibacillus sp. SK33, Virgibacillus sp. SK37, and Staphylococcus sp. SK1-1-5 were added separately to anchovy that was hydrolyzed by 0.25% Alcalase at 60 °C for 2 h followed by 0.5% Flavourzyme at 50 °C for 4 h. The mixtures were then adjusted to contain 25% solar salt and incubated at 35 °C for 4 mo. α-Amino contents of all inoculated samples were higher than the control (without the addition of starter culture) during the course of fermentation. After 4-mo fermentation, the samples inoculated with Staphylococcus sp. SK1-1-5 contained the highest α-amino content of 733.37 ± 13.89 mM while that of the control was 682.67 ± 3.33 mM. Amino acid profiles of inoculated samples showed similar patterns to that of commercial product fermented for 12 mo, with glutamic, aspartic, and lysine being predominant amino acids. Virgibacillus sp. SK33 appeared to decrease histamine content of fish sauce by 50% when compared to the control. Volatile compounds analyzed by GC–MS of all inoculated samples fermented for 4 mo exhibited a similar pattern to those of the 12-mo-old commercial product. Samples inoculated with Staphylococcus sp. SK1-1-5 produced higher levels of volatile fatty acids and showed similar sensory characteristics to the commercial fish sauce fermented for 12 mo. Staphylococcus sp. SK1-1-5 is a potential strain that can be applied to produce fish sauce with overall sensory characteristics of traditional fish sauce in shorter time.     

一株细菌型豆豉发酵菌种的筛选及鉴定

从临沂细菌型豆豉中筛选出一株适于豆豉生产的高产蛋白酶菌种,并对此菌种进行鉴定。结果表明：采用酪蛋白平板初筛,制曲复筛,根据曲样蛋白酶酶活以及游离态含量共选出5株优良菌株用于豆豉的制作,由成品豆豉的理化指标和感官评定认为D2号菌种发酵的豆豉风味好,滋味鲜美。结合生理生化和16SrDNA序列分析初步鉴定D2号菌种为枯草芽孢杆菌,该菌株来源于豆豉,属于安全菌种,具有研究开发价值。     

金枪鱼蒸煮液酶解工艺优化及风味海鲜调味汁的制备

以金枪鱼蒸煮液作为原料,制备风味海鲜调味汁。本实验以水解度为指标,从中性蛋白酶、碱性蛋白酶、木瓜蛋白酶、胃蛋白酶、胰酶中筛选得到最佳酶,在单因素实验基础上,通过响应面优化酶解工艺条件,利用正交实验L₉(34)研究不同酵母添加量、发酵温度、发酵时间对腥味值的影响,并确定最适杀菌条件。结果表明,以木瓜蛋白酶酶解金枪鱼蒸煮液,最佳酶解条件为:酶解时间4 h,酶解温度56 ℃,酶添加量300 U/g;酶解液经过添加酵母0.75%,在35 ℃下发酵60 min,去腥效果较佳;最佳杀菌条件为:90 ℃下灭菌30 min。研制出的金枪鱼调味汁呈黄棕色、鱼香味浓郁,氨基酸态氮含量0.68 g/100 mL,可以充分开发利用,是一种很有发展前景的天然调味品。