电渗析脱盐对鱼露氨基酸和挥发性风味物质组成的影响

本文采用电渗析(ED)技术对传统鱼露发酵液进行脱盐处理,结果表明,在电压为9 V,流速4 cm/s的条件下,目标盐含量为22%、20%、15%、10%、5%和2%(m/m)的鱼露的氨基态氮、氨基酸以及挥发性风味物质含量随脱盐程度的升高而呈非线性降低趋势。当盐含量降低为20%时,氨基态氮损失率为8%,损失率相对较低;游离氨基酸中几种苦味氨基酸如酪氨酸、精氨酸、组氨酸和赖氨酸损失的比例较大,鱼露中所有氨基酸的质量随着脱盐程度增加而降低,尤其是苦味氨基酸如酪氨酸、精氨酸、组氨酸和赖氨酸的损失率较大,当电渗析脱盐至盐含量为2%时,其质量损失率分别为51.60%、49.41%、42.41%和31.12%;挥发性风味物质种类不变,除2-甲基丁醛、3-甲基丁醛和苯甲醛相对百分含量增加外,酸类、酮类、含氮类和含硫类化合物的相对百分含量随着脱盐程度的增加而有所降低,但未低于其呈味阈值;感官评定结果显示当盐含量降低为20%时,电渗析脱盐对鱼露整体风味影响不大,同时利于鱼露的防腐保存,可为低盐鱼露的生产提供参考。     

Modeling and Optimization of Electrodialytic Desalination of Fish Sauce Using Artificial Neural Networks and Genetic Algorithm

Electrodialysis (ED) has been proposed as a means to reduce sodium ion concentration in fish sauce. However, no information is so far available on the optimum condition to operate the ED process. Artificial neural network (ANN)-based models were therefore developed to predict the ED performance and changes in selected quality attributes of ED-treated fish sauce; optimum operating condition of the process was then determined via multi-objective optimization using genetic algorithm (MOGA). The optimal ANN models were able to predict the ED performance with R ²?=?0.995, fish sauce basic characteristics with R ²?=?0.992, and the concentrations of total aroma compounds and total amino acids, flavor difference, and saltiness of the treated fish sauce with R ²?=?0.999. Through the use of MOGA, the optimum condition of the ED process was the use of an applied voltage of 6.3 V and the maintenance of the residual salt concentration of the treated fish sauce of 14.3 % (w/w).     

鱼露特征香气及增香微生物研究进展

鱼露风味浓郁、独特,是部分地区传统调味品。传统鱼露发酵周期过长及含盐量太高限制其发展;但低盐、速酿鱼露存在香气不足的缺陷。通过添加增香微生物加快鱼露香气形成或改善鱼露香气是提高鱼露品质的重要方法。本文综述了鱼露香气物质常用的检测、鉴定方法,归纳获得21种鱼露中最主要的特征香气物质,总结了10株改善鱼露香气的微生物,基于微生物氨基酸代谢途径,分析了鱼露部分特征香气物质产生机制,以期为鱼露品质改善提供参考。     

FISH SAUCE PRODUCTS AND MANUFACTURING: A REVIEW

Fish sauce, due to its characteristic flavor and taste, is a popular condiment for cooking and dipping. Biochemically, fish sauce is salt-soluble protein in the form of amino acids and peptides. It is developed microbiologically with halophilic bacteria, which are principally responsible for flavor and aroma. This review article covers the manufacturing methods of fish sauce, factors affecting the quality of fish sauce, nutritional values of fish sauce, microorganisms involved with fermentation, and flavor. In addition, rapid fermentation to reduce time and new parameters to estimate the quality of fish sauce are reviewed. Along with a new approach for estimating the quality of fish sauce, the quantitative analysis of degradation compounds from ATP and other specific protein compounds in fish sauce are discussed.     

FISH SAUCE PRODUCTS AND MANUFACTURING: A REVIEW

Fish sauce, due to its characteristic flavor and taste, is a popular condiment for cooking and dipping. Biochemically, fish sauce is salt-soluble protein in the form of amino acids and peptides. It is developed microbiologically with halophilic bacteria, which are principally responsible for flavor and aroma. This review article covers the manufacturing methods of fish sauce, factors affecting the quality of fish sauce, nutritional values of fish sauce, microorganisms involved with fermentation, and flavor. In addition, rapid fermentation to reduce time and new parameters to estimate the quality of fish sauce are reviewed. Along with a new approach for estimating the quality of fish sauce, the quantitative analysis of degradation compounds from ATP and other specific protein compounds in fish sauce are discussed.     

Electrodialysis Desalination of Fish Sauce: Electrodialysis Performance and Product Quality

ABSTRACT:  Fish sauce has a unique, pleasant flavor, but contains high levels of sodium chloride, which is nowadays not desirable for health-conscious consumers. Although many researchers have attempted to solve this problem by substituting sodium with potassium in fish sauce, potassium-based products are still unsuitable for patients with kidney disease. Thus, electrodialysis (ED) desalination of fish sauce was carried out. The rate of salt removal, evolution of total soluble solids, and electrical conductivity of the electrodialysis-treated fish sauce were investigated. Moreover, the system performance in terms of yield, energy consumption, and current efficiency were examined. Density, viscosity, ion concentrations (that is, Na⁺, K⁺), total nitrogen, amino nitrogen, and color were investigated at various values of input voltage (6, 7, and 8 V) and remaining salt concentration (22%, 18%, 14%, 10%, 6%, and 2%[w/w]). The results indicated that an increase in the input voltage led to an increase in the rates of salt removal, electrical conductivity, and total soluble solids. The energy consumption increased whereas current efficiency and yield decreased significantly with an increase in input voltage and the salt removal level. Physicochemical properties of the treated fish sauce, in terms of the total soluble solids, density, viscosity, ion concentrations (that is, Na⁺, K⁺), total nitrogen, and color were significantly affected by the input voltage and the salt-removal level.     

酵母抽提物协助酱油减盐后对其风味物质的影响研究

该研究通过使用酱香型酵母抽提物（YE）协助酱油减盐,并对减盐前后酱油风味物质的变化进行分析。结果表明,通过减少原油用量直接减盐20%和30%后,酱油的关键理化指标以及游离氨基酸、小分子肽和挥发性芳香成分等风味物质含量均相应损失20%和30%,酱油味也被明显稀释。而酱香型YE协助减盐20%和30%后酱油的游离氨基酸、小分子肽和挥发性芳香成分总量分别可达到减盐前的99.98%～100.78%、98.40%～99.03%和95.66%～97.13%,且酱油味得以恢复,从而实现了酱油的减盐不减味。     

典型广式酱油与日式酱油的风味物质差异研究

广式酱油和日式酱油在原料、微生物和工艺均有极大的差异。通过比较研究,广式酱油酱香、豉香浓郁,而日式酱油醇香、酯香和甜味更加突出。在氨基酸分析中,广式酱油的总游离氨基酸为5.220 g/100 mL,而日式酱油则为5.903 g/100 mL,但两者氨基酸种类的相对百分含量没有显著的差异（P＞0.05）。气相色谱-质谱法（GC-MS）鉴定出挥发性化合物134种,其中广式酱油的主要挥发性化合物为酯类（25.39%）、醇类（25.23%）、酸类（13.51%）、酮类（4.24%）、醛类（2.57%）、酚类（0.31%）和烷烃类（28.75%）,而日式酱油主要为酯类（56.02%）、醇类（21.11%）、酸类（5.92%）、酮类（3.42%）、醛类（0.69%）、酚类（0.15%）和烷烃类（12.69%）,酱油挥发性化合物的种类、含量及比例构成是引起两种酱油风味独特差异的重要原因。     

低钠复合盐对发酵香肠理化特性及风味的影响

以添加58%氯化钠、30%氯化钾、7%氯化钙、5%甘氨酸的低钠复合盐发酵香肠作为实验组,以100%氯化钠为对照组,通过测定理化指标、感官评价、电子舌味觉特征、游离氨基酸含量以及挥发性风味物质等探究低钠复合盐对发酵香肠品质的影响。结果表明：在香肠发酵成熟过程中,香肠pH值、水分含量呈显著下降趋势,钠含量显著增加。实验组pH值显著低于对照组,水分含量显著高于对照组,并且对产品的色泽和质构特性有一定改善作用,实验组在显著降低钠含量的同时,感官评价与对照组无明显差异。根据电子舌分析,实验组的鲜味、丰富度、苦味显著高于对照组。此外,实验组促进了游离氨基酸的释放,并对挥发性风味物质的产生没有负面影响。因此,实验组在减少42%食盐添加量的基础上,保证了发酵香肠良好感官和风味品质。     

一株戊糖片球菌(Pediococcus pentosaceus)在模拟鱼露中的代谢行为及转录组学分析

本文采用模拟鱼露体系,通过化学成分分析及转录组测序的手段研究了接种Pediococcus pentosaceus对鱼露发酵效果的影响。结果发现Pediococcus pentosaceus可显著提高鱼露中Glu、Gly、Ala、Ser、Asp等良好风味氨基酸的含量,降低Phe等不良风味氨基酸含量;并且鱼露的挥发性成分中烃类、酯类的成分的种类和含量均大幅减少,芳香族化合物的种类大大减少但总量大幅增加;而醛类、酮类、酸类和胺类成分的种类和含量均显著增加;感官评定结果表明接种Pediococcus pentosaceus可显著改善鱼露的鲜味和香气。转录组测序结果表明,在模拟鱼露中Pediococcus pentosaceus的碳水化合物和氨基酸的代谢最为活跃,且处于最活跃的代谢通路中的氨基酸也是鱼露中含量变化最大的氨基酸;还发现Pediococcus pentosaceus有较强的蛋白酶和肽酶活性;柠檬烯和松萜的降解也是Pediococcus pentosaceus的主要代谢通路之一,该通路与挥发性成分的产生有关;本研究未发现Pediococcus pentosaceus在模拟鱼露发酵过程中有氨基酸脱羧酶表达。     

全大豆和脱脂大豆酿造酱油的差异化研究

全大豆和脱脂大豆的主要成分差异是有机溶剂浸出的油脂类物质,分别以全大豆和脱脂大豆为主要原料酿造酱油试验,利用理化指标、感官鉴评和气相色谱-质谱法（GC-MS）分析2种酿造酱油的品质差异。研究结果表明,全大豆酿造酱油整体滋味协调,醇香、酱香浓郁,色泽棕红亮,而脱脂大豆酿造酱油滋味一般,酸味较强,醇香和酱香较淡,色泽较深。GC-MS鉴定出挥发性风味化合物47种,其中全大豆酿造酱油的主要挥发性化合物为酯类28.75%、醇类25.27%、酚类19.17%、酸类18.24%和醛酮类3.75%,而脱脂大豆酿造酱油的主要挥发性化合物为醇类50.50%、酯类26.25%、酸类16.16%、醛酮类2.86%和酚类0.99%,挥发性香气化合物的相对含量差异是引起2种酱油风味差异的主要原因。     

Electrodialytic Removal of Nitrate from Pineapple Juice: Effect on Selected Physicochemical Properties,Amino Acids,and Aroma Components of the Juice

This study aimed at investigating the effect of nitrate removal from pineapple juice by electrodialysis (ED) on selected properties of the ED‐treated juice. Single‐strength pineapple juice with reduced pulp content was treated by ED to reduce the nitrate concentration to 15, 10, or 5 ppm. After ED, the removed pulp was added to the ED‐treated juice and its properties, including electrical conductivity, acidity, pH, total soluble solids (TSS), color, amino acids, and selected aroma compounds, were determined and compared with those of the untreated juice. ED could reduce the nitrate content of 1 L of pineapple juice from an initial value of 50 ppm to less than 5 ppm within 30 min. A significant decrease in the electrical conductivity, acidity, pH, TSS, and yellowness, but a significant increase in the lightness, of the juice was observed upon ED. Concentrations of almost all amino acids of the ED‐treated juice significantly decreased. The concentrations of 8 major compound contributors to the pineapple aroma also significantly decreased. Adding the pulp back to the ED‐treated juice increased the amino acids concentrations; however, it led to a significant decrease in the concentrations of the aroma compounds.     

Olfactometric characterization of aroma active compounds in fermented fish paste in comparison with fish sauce,fermented soy paste and sauce products

Aroma active compounds in commercial fermented fish meat paste product (fish miso), fermented soy paste (soy miso), fish sauce and soy sauces were characterized by using a dynamic headspace method for volatile isolation and GC olfactometry for odor perception. A total of 123 volatile compounds consisting mainly of aldehydes, alcohols, esters, ketones, furans, sulfur and nitrogen-containing compounds, aromatics and acids were consistently identified. A major 16 odor-active compounds were distinguished to contribute as key aroma compounds for the miso and sauce products. Olfactometric and sensory findings clearly differentiated miso products with caramelic, fruity aroma notes, whereas fish sauce products were characterized by ammoniacal, fishy, nutty and cheesy odor note. Soy sauce products, however, were dominated by nutty and cheese aroma. Use of koji for fish miso production was found effective to enhance sweet aroma to the product with a reduction of nutty, meaty and rancid nuance. Principal component analysis employed for statistical interpretations clearly elucidated the relationship among different types of fermented products.     

秋刀鱼鱼露速酿加工工艺研究

为了研究鱼露快速发酵生产工艺,以秋刀鱼为原料,采用加曲适量保温的方式生产鱼露,通过单因素实验探讨不同因素(发酵周期、温度、固液比、加盐量、加曲量)对鱼露发酵生产的影响,并在此基础上进行正交实验工艺优化,结果表明,在发酵周期30 d时,鱼露发酵液中氨基酸态氮含量维持稳定,表明鱼肉组织基本分解完全,最佳发酵工艺条件为:温度30℃、固液比1∶0.6、加曲量5%、加盐量12%。在此条件下制得的鱼露氨基酸态氮含量(0.97±0.02)g/100 m L,可溶性固形物含量23%±0.51%,感官评分88分,鱼露颜色棕红至橙红,无异味,富有鱼露特殊香气,达到快速生产鱼露目的。      

Effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of a sailfin sandfish (Arctoscopus japonicus) fish sauce

The effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of fish sauce produced from sailfin sandfish (Arctoscopus japonicus) with different salt concentrations (10% and 20%) were investigated over 10 months. Fish sauces prepared from sailfin sandfish with rice koji and a low salt concentration had higher total nitrogen, amino nitrogen and total free amino acid than did those without rice koji or with a high salt concentration. Sensory evaluation of fish sauces prepared with rice koji and a low salt concentration found better taste, flavour and overall acceptance than those prepared without rice koji during fermentation (P < 0.05). The use of rice koji increased the total nitrogen, amino nitrogen and free amino acid and also enhanced the sensory qualities during fermentation. These results suggest that the use of rice koji can result in a low‐salt fish sauce with better flavour.     

Application effects of NaCl substitute on the fermentation profile of Pixian douban (broad bean paste)

The effects of a reduced-salt substitute (composed of NaCl, sodium gluconate, KCl, L-histidine, and L-lysine) applied in the fermentation of traditional Pixian douban (PXDB) were explored in this study according to sensory quality, physicochemical characteristics, color, colony count, and the contents of free amino acids (FAAs), organic acids, and volatile flavor compounds. The results showed that the PXDB with a 15% salt substitution had the most attractive reddish-brown color, a mellow fragrance, and the lowest total colony count of the three pastes. The fermentation quality of the 15% salt substitute PXDB was superior to that of the control groups, its sensory quality was more readily accepted, and the contents of its amino acid nitrogen, FAAs and organic acids had increased by 0.1050, 0.3290, and 3.9068 mg/g, respectively. Moreover, the concentrations of the main aroma compounds in the PXDB containing the salt substitute were higher than those of the control. These included phenylethanol, 3-methylthiopropanol, isoamyl alcohol, furfural, benzaldehyde, phenylacetaldehyde, nonanal, isoamyl aldehyde, 4-ethylphenol, and, particularly, 2,6-dimethylpyrazine, which had increased as much as 100 times. Correlation analysis showed that Glu, Phe, Tyr, Gly, Leu, Val, Asp, Ile, citric acids, and succinic acids were all positively correlated with the main aroma and contributed to the generation of PXDB's characteristic flavor, and main aroma substances in turn positively influence PXDB flavor sensory attributes. Overall, these results showed the application of the 15% salt substitute during PXDB fermentation improved the quality of the paste and, thus, would benefit the development of reduced-salt PXDB.     

Effect of electrodialysis pretreatment on physicochemical properties and morphology of spray-dried-fish sauce powder

Fish sauce is a popular Asian food ingredient having specific flavor that gives pleasure to the senses of taste. However, fish sauce contains high-salt content, which is nowadays not desirable by health-conscious consumers. Recently, it has been shown that electrodialysis succeeds in reducing the salt content of fish sauce without affecting its important characteristics over a specific range of residual salt content. In this study the effect of electrodialysis pretreatment prior to spray drying to produce low-salt fish sauce powder, which is a more shelf-stable and convenient product compared with liquid fish sauce, was investigated. Product recovery, morphology and selected physicochemical properties, i.e., moisture content, water activity, hygroscopicity, as well as X-ray diffraction (XRD) patterns of the fish sauce powder were determined. The ED-treated-fish sauces of various salt contents (in the range of approximately 2–25% w/w) were spray dried at inlet drying air temperatures of 120–180 °C. It was found that the feed salt concentration and inlet air temperature had significant effects on all observed variables. This is due to the fact that the feed salt concentration strongly affected water removal from the ED-treated-fish sauce during spray drying, leading to significant alterations of the ED-treated-fish sauce powder properties.     

高盐稀态牡蛎酿造酱油的开发与品质分析

以豆粕、小麦及牡蛎酶解液为原料,采用高盐稀态发酵工艺,研发具有甜香风味的功能性牡蛎酱油,并将其与对照酱油的感官品质、氨基酸含量及风味成分进行了分析比较。结果表明,在牡蛎酶解液添加量为25%时,牡蛎酱油的氨基态氮含量达1.2 g/100 mL。牡蛎酱油较对照酱油在海鲜风味方面更为突出,同时在鲜度、香气方面以及整体评价也更佳。牡蛎酱油和对照酱油均鉴定出6种鲜味氨基酸,但牡蛎酱油的鲜味氨基酸含量（41.8%）高于对照酱油（40.5%）;牡蛎酱油中牛磺酸含量高达36.7 mg/100 g,约为对照酱油的13.6倍。牡蛎酱油的挥发性风味物质中醇类、呋喃类相对含量较高,分别为59.5%、20.7%,从而赋予其香浓而独特的风味。     

Bacteriological properties and health-related biochemical components of fermented fish sauce: An overview

Fish sauce is an amber-colored salty liquid in Southeast Asian cuisine used as an important condiment for improving the taste of foods. It is produced by fermenting the fish with salt in the ratios of 1:1 or 3:1 (fish:salt, wet wt) in underground concrete tanks or earthenware for 6–12 months at ambient conditions. Proteins of the raw materials are hydrolyzed into peptides and amino acids by microbial proteolytic enzymes during fermentation. This paper reviews fish sauce diversity and its bacteriological, biochemical, and biofunctional properties. Additionally, efforts to accelerate fish sauce production by employing halotolerant bacterial cultures and proteinases to reduce the fermentation period and also to improve the acceptability of the product are also reviewed. Further, the review provides an overview of bacterial proteinases that have been employed to enhance the sensory and microbiological quality of fish sauce. The review also outlines the effect of fermented fish sauces on health, especially in reference to several bioactive peptides and bacterial metabolites apart from discussing desalination technique to recover the metabolites from fish sauce.