臭鳜鱼的风味物质及风味活性物质分析

通过优化固相微萃取条件,结合气相色谱-质谱联用仪(GC-MS)分离鉴定徽州臭鳜鱼挥发性风味物质,并进一步鉴定其风味活性物质。结合谱库以及保留指数比对,在臭鳜鱼中共鉴定出45种风味物质。根据其结构性质分为9类,其中醇类含量最高,约占总风味成分的62.60%,酸类、芳香类、含氮、含硫化合物等次之。通过计算气味活度值(OAV)并进一步用标准品进行分析,共鉴定出13种风味活性物质,其中丁酸、三甲胺、芳樟醇OAV值较大,对整体风味品质具有重要贡献。     

盐渍鱼酶解制备鱼露及挥发性风味物质的研究

在对Alcalase2.4L和Papain双酶分步酶解盐渍鱼酶解过程研究的基础上酶解鲜鱼和半年盐渍鱼制备鱼露,运用感官分析和顶空固相微萃取(HS-SPME)结合气质联用(GC-MS)法对其风味进行比较分析。结果表明:Alcalase2.4L、Papain双酶分步酶解盐渍鱼酶解效果较好,先加Papain6h后再加Alcalase2.4L效果较好,但鲜味氨基酸的比例不如先加Alcalase2.4L后加Papain高;与鲜鱼酶解鱼露相比,虽然盐渍鱼使蛋白酶的酶解效果有所降低,但盐渍鱼酶解鱼露的风味较好,较接近传统鱼露的风味,且含有挥发性酸类,但具有鱼露特征香味的挥发性风味物质没有检出,说明需进一步发酵才能达到传统成熟鱼露的风味。     

Characterization of flavour and volatile compounds of fermented squid using electronic nose and HPMS in combination with GC-MS

The present study investigated the flavour characteristics and key volatile components of fermented squid (Dosidicus gigas) as well as their formation mechanism by three different starter cultures of lactic acid bacteria (LAB) and natural squid. The sensory assessment, volatile compounds, as well as the amino acids of the mixed fermented squid were detected using pickled brine as samples of fermented squid. A total 88 types of volatile compounds were found in four samples by 0–72 h of fermentation. After fermentation by LAB, the volatile compounds of squid showed that the fermented squid with different started cultures differed mainly in terms of numbers of alcohols, ketones, and esters. Furthermore, the amounts of volatile compounds among three starter cultures were also obviously different. Gas Chromatography-Mass Spectrometer (GC-MS) analysis indicated that the mixed fermentation process contained relatively higher (+)-limonene (11.71%) (lemon scent) and 3-hydroxy-2-butanone (5.72%) (creamy taste). These compounds were not detected in the control group. The main flavour compounds of nonanal and 2, 4-decadienal were gradually reduced. Meanwhile, 2, 3-butanedione, 2-heptanone, 2-pentylfuran, and nonanoic acid are the key flavour components. The total principal component is 94.01%, which were clarified by electronic nose in combination with principal components analysis. After mixed fermentation by LAB, the total amino acid (TAA) content reached 85.36 g/100 g, which was almost twice the amount of the control, especially in aspartate, glutamate, and threonine. Our results indicated that LAB has obvious effects on deodorization and flavour promotion during the fermentation of squid. This study provided an important basis for the further development and utilization of squid.     

食用胶对鸭肉脯保藏期间挥发性风味物质变化的研究

随着保藏时间的延长鸭肉脯中的挥发性风味物质会逐渐挥发,造成鸭肉脯的风味减淡,影响鸭肉脯的品质,因此在加工的过程中需要采取措施以保持鸭肉脯在保藏过程中的挥发性风味物质的稳定性,以鸭肉为原料,研究了鸭肉脯在加工过程中添加黄原胶、卡拉胶、阿拉伯胶和魔芋胶对鸭肉脯保藏期间挥发性风味物质变化规律的影响。采用顶空固相微萃取技术和气相色谱质谱联用检测方(HS-SPEM-GC-MS)对鸭肉脯的挥发性风味物质进行萃取和检测,研究结果表明,添加食用胶后可以减缓鸭肉脯挥发性风味物质总含量的挥发速度,有效的保持了鸭肉脯的挥发性风味物质,同时添加食用胶对鸭肉脯中主要挥发性风味物质中的壬醛、草蒿脑等起到较好的保持作用,从而有利于延长鸭肉脯的保藏时间风味稳定性。     

发酵牦牛肉成熟过程中挥发性香气成分的变化

为探讨发酵牦牛肉挥发性香气成分在成熟过程中的变化规律,本文采用固相微萃取法（SPME）对各取样点样品中挥发性物质进行提取,利用气相-嗅闻-质谱联用法对其中的挥发性成分进行定性和定量分析。总计有84种挥发性成分被鉴定,其中,经嗅闻鉴定的香气活性化合物有48种,包括烃类（12）、醇类（8）、酮类（7）、醛类（3）、酸类（3）、含硫化合物（2）、酯类（4）、含氮类化合物（7）和酚类（2）。在成熟过程中,烃类和酮类含量整体呈现波动变化。醛类和酯类含量在成熟前期增加,而后又降低。酸类和吡嗪类形成于成熟过程,含量逐渐增加。烃类是成品发酵牦牛肉风味组成中含量最高的,其次是醇类、酮类及吡嗪类化合物。香辛料的添加、氨基酸的降解及微生物的代谢对发酵牦牛肉的香气形成具有重要作用。      

冷藏期间真空包装鲻鱼肉中特征性挥发物研究

为了探讨鲻鱼肉中特征性挥发物,利用顶空固相微萃取-气-质联用（HS-SPME-GC-MS）法检测真空包装0℃下贮藏期间鲻鱼肉挥发性风味。实验结果显示,共鉴定出七大类76种化合物,并分析贮藏期间鲻鱼肉中主要的挥发物相对含量变化、气味特征及其来源。研究发现,鲻鱼挥发性风味以烃类、杂环类、醇类和醛类为主,冷藏期间一直能够被检测到的8种主要特征性挥发物分别为:十二烷、十六烷、二十八烷、甲苯、萘、2,4-二叔丁基苯酚、二丁基羟基甲苯和亚硫酸。通过主成分分析冷藏期间鲻鱼特征性挥发物变化规律,提炼出4个主成分因子,为进一步研究鲻鱼挥发性风味成分奠定了基础。      

Change of volatile compounds in fresh fish meat during ice storage

Abstract: The change of volatile compounds in fresh fish meat during 3‐ to 4‐d ice storage was investigated for several fishes using an electronic nose system and a gas chromatography‐mass spectrometer (GC/MS) with headspace solid‐phase micro‐extraction (SPME). Principal component analyses for samples using the electronic nose system revealed that the increase of some volatile compounds during storage was rapid in sardine (Sardinops melanostictus), jack mackerel (Trachurus japonicus), and chub mackerel (Scomber japonicus); moderate in yellowtail (Seriola quinqueradiata), skipjack (Katsuwonus pelamis), and young oriental bluefin tuna (Thunnus thynnus). In contrast to these fishes, the change was little in “white meat” fishes such as red seabream (Chrysophrys major), Japanese seabass (Lateolabrax japonicus), flatfish (Paralichthys olivaceus), puffer (Lagocephalus wheeleri), and bartail flathead (Platycephalus indicus). SPME‐GC/MS analysis showed that some aldehydes and alcohols such as 1‐heptanol, (E)‐2‐octenal, (E)‐2‐hexenal, 1‐pentanol, (E,E)‐2,4‐heptadienal,2,4‐hexadienal, 1‐hexanol, 4‐heptenal, and so forth increased rapidly in jack mackerel and chub mackerel, slowly in skipjack, and a little in red seabream and puffer during the storage. The increase of these compounds was considered to have an effect on the change of electronic nose response. Hexanal was a dominant compound increased from the beginning of the storage in jack mackerel. The increase of volatile compounds was little in red seabream and puffer. The increase of these aldehydes and alcohols was thought to be an appropriate marker for monitoring the freshness of “fresh” fish except for white meat fish. Practical Application: The results of this study are ready to apply for preventing fishy off‐flavor of fisheries products. Lipid oxidative derivatives other than trimethylamine contributed to fresh fish flavor; therefore, to prevent lipid oxidation seemed important.     

四川白口仔姜在贮藏过程中挥发性成分的变化

为研究仔姜在沙土贮藏过程中挥发性风味物质的变化,将采收的仔姜经过挑选、分级、杀菌处理后埋藏在沙土中,并于11℃贮藏,采用固相微萃取—气相色谱—质谱联用测定不同时期贮藏过程中仔姜的挥发性风味物质。结果表明:贮藏过程中从仔姜中共检测出77种挥发性成分,分别为烃类(47种)、醇类(16种)、酮类(1种)、醛类(4种)、醚类(9种),其中烃类、酮类物质总量在贮藏过程中(10,20,30d)无显著差异(P0.05),醇类物质总量在20d时显著降低,30d后显著升高。贮藏过程中仔姜有10种挥发性成分的含量随着贮藏时间延长显著升高,分别为左旋-α-蒎烯、莰烯、2,6-二甲基-2,6-辛二烯、反-β-金合欢烯、别香橙烯、2-茨醇、α-松油醇、香茅醇、香茅醛、柠檬醛,在30d时这些物质含量分别是新鲜样品的5.09,7.89,6.73,10.48,153.75,11.11,8.21,11.73,24.96,14.65倍。     

Characterization of major volatile compounds in whey spirits produced by different distillation stages of fermented lactose-supplemented whey

This research aimed to advance the understanding of acceptable sensory qualities of potable whey-based spirit from nonsupplemented, mid-supplemented, and high-supplemented whey samples by analyzing major volatile compounds during different stages of distillation (head, heart, and tail). The results demonstrated that commercial Saccharomyces cerevisiae strain in lactase-hydrolyzed whey showed rapid and complete sugar hydrolysis and efficient ethanol production in 24, 30, and 36 h on average, producing up to 29.5, 42.1, and 56.4 g/L of ethanol, respectively. The variations in titratable acidity, specific gravity, pH value, residual protein, sugar content, and alcohol yield were investigated during the fermentation. The total amount of volatile compound concentrations significantly decreased from the head (2,087–2,549 mg/L) to the tail whey spirits (890–1,407 mg/L). In the whey spirit, 2-methyl-1-butanol, 3-methyl-1-butanol, 2-methyl-1-propanol, 1-propanol, acetaldehyde, and ethyl acetate were the most prevalent dominant compounds, accounting for the largest proportion of total volatile compounds. The volatile compounds detected were far below the acceptable legal limit. The results suggest that high sensory qualities of potable whey-based spirits can be produced by fermentation of lactose-supplemented whey with S. cerevisiae cells.     

米曲霉发酵罗非鱼及产物挥发性成分分析

采用米曲霉发酵罗非鱼制备腊鱼风味的咸味香精基料,初步确定发酵工艺如下:温度为37℃,接种量（米曲霉单位数/鱼肉重）为4×108cfu/g,料液比（鱼肉重/水重）为0.2（w/w）,发酵时间为40h,产品具有明显腊鱼香味,无明显腥臭味,香气浓烈持久;采用聚二甲基硅氧烷/二乙烯基苯型涂层纤维萃取头（PDMS/DVB）,通过固相微萃取和气质联用技术（SPME-GC-MS）分析鉴定发酵前后挥发性成分,分别鉴定出53种和75种化合物,其中发酵后产品中的醛类和醇类相对含量较高,检测到较高含量的壬醛、正己醛、辛醇、3-羟基丁酮、2-十一酮、1-辛烯-3-醇,其中壬醛、己醛和辛醇均具有特殊的脂肪气息,1-辛烯-3-醇具有明显的蘑菇和泥土味,2-十一酮具有典型牛奶香气。      

微生物发酵剂对发酵香肠中挥发性成分的影响

采用固相微萃取技术结合GC/MS,以壬烷作内标进行定性和半定量,分析自然发酵和添加发酵剂生产的两组发酵香肠的挥发性成分,共鉴定出39种挥发性成分。其中自然发酵组鉴定出35种,总含量为9.486μg等量壬烷/g发酵香肠;添加发酵剂组鉴定出32种,总含量为18.313μg等量壬烷/g发酵香肠。自然发酵香肠主要挥发性成分由萜烯类(27.71%)、酸类(26.42%)和酯类(25.32%)组成;在添加发酵剂组中,最重要的组成是酯类(42.10%),其次为酸类(26.52%)和萜烯类(18.07%)。     

Impact of yeast starter formulations on the production of volatile compounds during wine fermentation

The most diffused starter formulation in winemaking is actually represented by active dry yeast (ADY). Spray‐drying has been reported as an appropriate preservation method for yeast and other micro‐organisms. Despite the numerous advantages of this method, the high air temperatures used can negatively affect cell viability and the fermentative performance of dried cells. In the present study, 11 wine S. cerevisiae strains (both indigenous and commercial) were submitted to spray‐drying; different process conditions were tested in order to select the conditions allowing the highest strain survival. The strains exhibited high variability for tolerance to spray‐drying treatment. Selected strains were tested in fermentation at laboratory scale in different formulations (free fresh cells, free dried cells, immobilized fresh cells and immobilized dried cells), in order to assess the influence of starter formulation on fermentative fitness of strains and aromatic quality of wine. The analysis of volatile fraction in the experimental wines produced by selected strains in different formulations allowed identification of > 50 aromatic compounds (alcohols, esters, ketones, aldehydes and terpenes). The results obtained showed that the starter formulation significantly influenced the content of volatile compounds. In particular, the wines obtained by strains in dried forms (as both free and immobilized cells) contained higher numbers of volatile compounds than wines obtained from fresh cells. Copyright © 2014 John Wiley & Sons, Ltd.     

Vacuum-packed ripened sausages: evolution of volatile compounds during storage

BACKGROUND: Various studies have shown the ability of volatile compounds to influence the quality of charcuterie products because of their effect on sensorial properties. To the best of our knowledge, there are no data in the scientific literature concerning the evolution of volatile compounds of vacuum‐packed ripened sausages over time. The aim of this work was to evaluate the evolution of volatile compounds in vacuum‐packed ripened sausages over time, considering that this kind of packaging is the most commonly used to prolong the shelf‐life of these products. RESULTS: Sixty‐nine volatile compounds were identified. Those derived from spices represented the prevailing compounds at the beginning of storage and significantly decreased (P < 0.001) during 5 months of storage, as a result of the well‐known antioxidant activity. Conversely, compounds derived from the autoxidation of lipids, which are among those chiefly responsible of sensorial properties of meat products, significantly increased (P < 0.001). CONCLUSION: The research demonstrated that vacuum packaging influenced the evolution of volatile compounds during storage of ripened sausages. In particular, the increase of volatile compounds derived from autoxidation of the lipid fraction indicated that oxidative processes involved the fatty fraction of ripened sausages also in the scarcity of oxygen. Copyright © 2011 Society of Chemical Industry     

油菜花粉油脂贮藏过程中挥发性成分变化研究

采用顶空固相微萃取与气相色谱质谱联用技术对油菜花粉油脂在贮藏前后挥发性成分进行了分析。结果表明,新鲜油菜花粉油脂特殊风味物质的主要成分为D-柠檬烯(13.66%)、3-蒈烯(7.95%)、二甲基富烯(5.72%)、β-水芹烯(4.58%)、苯甲醛(3.15%)、氧化石竹烯(2.27%)、苯乙醇(1.16%)和β-蒎烯(1.12%)等化合物。经过常温贮藏6个月后油脂的主要挥发性成分为醛类和酯类化合物。油菜花粉油脂中的高含量亚麻酸导致其易氧化酸败。经分析鉴定出油菜花粉油脂氧化产物含有丙醛、(E)-2-戊烯醛、正己醛、(E)-2-己烯醛、(E,E)-2,4-己二烯醛、(E)-2-辛烯醛、壬醛和(E,E)-2,6-壬二烯醛和2,4-庚二烯醛等。其中2,4-庚二烯醛的含量最高,可作为油菜花粉油脂产品质量优劣的指标。     

Development of normal and branched chain volatile fatty acids during the fermentation process in the manufacture of fish sauce

The formation of volatile fatty acids (VFAs) in fish sauce was investigated. When fish were allowed to spoil prior to salting, very high concentrations of VFAs were produced. The increase was probably caused by microbial action. Addition of salt to spoiled fish seemed to inhibit microbial action, thus suppressing the formation of VFAs. The contents of short and long straight chain VFAs in aerobically fermented sauces were significantly higher than in anaerobically fermented sauces, suggesting that straight chain VFAs developed from fish fats. Certain branched VFAs were derived from the degradation of specific amino acids, such as isobutyric acid from valine and isovaleric acid from leucine. Alanine and isoleucine did not have a clear influence on the production of VFAs. © 2001 Society of Chemical Industry     

Characterization of volatile compounds in fermented milk using solid-phase microextraction methods coupled with gas chromatography-mass spectrometry

Lactic acid bacteria (LAB) are industrially important bacteria that are widely used in the fermented food industry, especially in the manufacture of yogurt. Characteristic flavors are produced by LAB during fermentation and storage that affect the quality and acceptability of fermented milk products. In this study, the volatile compounds in milk fermented by Streptococcus thermophilus IMAU80842 alone, Lactobacillus delbrueckii ssp. bulgaricus IMAU20401 alone, or both species together were identified using solid-phase microextraction methods coupled with gas chromatography-mass spectrometry. A total of 53, 43, and 32 volatile compounds were identified in milk fermented by S. thermophilus alone, L. delbrueckii ssp. bulgaricus alone, or both species together, respectively. The presence of some important flavor compounds was confirmed: acetic acid, acetaldehyde, acetoin, 2,3-butanedione, ethanol, and 1-heptanol. Our results demonstrate that the composition of the volatile compounds in fermented milk depends on the species of LAB used and whether they are used alone or in combination. This is important for the selection of appropriate starter cultures for the production of different types of fermented milk product with particular flavors.     

罐罐肉加工与贮藏过程中挥发性物质变化的研究

为了探明雅安罐罐肉挥发性物质的变化规律,本研究以不同加工与贮藏阶段的罐罐肉为对象,用同时蒸馏萃取结合气相色谱/质谱法对挥发性化合物进行分析。结果显示,罐罐肉在加工与贮藏过程中共检测出120种挥发性物质,醇、醛、酮、烃、酰胺、酯是主要成分,其中以己醛和2,4-癸二烯醛为主的醛类物质相对含量最高（最高达64.42%）。在加工过程中醛、酮、酯显著增加,并检测出酰胺类物质。在贮藏过程中醇、醛、酮的相对含量整体呈现下降趋势,烃类、酰胺类、酯类和其他化合物的相对含量整体呈上升趋势,并新产生了（2E）-2-十一碳烯醛、甲酸己酯、（Z）-9-十八烯酸酰胺和2-戊基呋喃等物质。      

顶空固相微萃取-气质联用法分析麒麟菜中的挥发性成分

以麒麟菜为研究对象,采用顶空固相微萃取（HS-SPME）技术对其挥发性成分进行了萃取,用气相色谱-质谱联用仪（GC-MS）进行了成分鉴定分析。结果显示,麒麟菜挥发性成分中共检出58种物质,其中醛类化合物17种,含量最高为54.10%;烃类化合物27种（其中芳香烃类8种）,含量为23.19%（其中芳香烃类物质含量为10.66%）;酯类化合物4种,占总量的11.68%;酮类化合物5种,占11.03%;醇类2种,含量为0.68%;其他物质共3种,占总量的0.77%。含量较高的单一化合物主要有:壬醛（18.45%）、异佛尔酮（7.75%）、邻苯二甲酸二乙酯（7.50%）、庚醛（7.13%）、己醛（6.33%）、辛醛（6.31%）、乙酸正丁酯（3.65%）、甲苯（3.29%）、癸醛（2.81%）、十二烷（2.21%）等。总体上,醛类化合物对麒麟菜的风味影响较大,其他如酯类、烃类等化合物对麒麟菜的风味有一定影响。