SDE-GC-MS分析奶香发酵风味物的致香成分

为更好地了解乳酸菌的发酵产香特性,本实验利用同时蒸馏萃取-气相色谱-质谱联用技术(SDE-GC-MS)对乳酸菌单菌种分别以牛奶、奶油为基料发酵产奶香风味物的致香成分进行分析比较,分别地鉴定出13种、19种风味物质,一共包括酯类化合物4种、酸类化合物4种、羰基化合物13种、醇类化合物1种、芳环化合物3种、不饱和化学物1种。对比两种奶香风味物致香成分发现,以奶油为基料发酵产奶香风味物的致香成分中,所含的羰基化合物种类较丰富,而以牛奶为基料发酵产生的酯类化合物较多。     

新型稀奶油-大豆分离蛋白香基的制备

为了丰富奶味香基蛋白源营养种类、降低成本并增强其风味强度,选用大豆分离蛋白部分替代稀奶油构建复合体系,采用两种不同的酶法结合乳酸菌发酵法,开发新型奶味香基,同时对两款香基的感官特性、主要代谢物和风味物质进行分析。结果表明,一步酶法结合发酵制备的香基具有较高水平的游离脂肪酸和中长链挥发性酸,并因此呈现出刺激性的酸败味等不良风味;而两步酶法结合发酵制备的香基积累了更高含量的多肽和氨基酸,短链挥发性酸以及3-羟基-2-丁酮、苯甲醛、糠醛、δ-十二内酯等重要挥发性风味物质,并获得更高的感官评价分数,更适于制备新型稀奶油-大豆分离蛋白复合风味香基。     

奶香型卷烟纸特征成分的释放迁移行为

制备了3种不同奶香卷烟纸并制成卷烟,考察其特征成分的释放及迁移行为.结果表明,奶香香精和奶香型卷烟纸的特征成分为香兰素、乙基香兰素,且是奶香型卷烟的嗅香来源.加香卷烟纸奶香特征成分会有效迁移到主流烟气中,卷烟抽吸前3 口的特征成分迁移量基本一致.奶香型卷烟放置4个月后,烟丝中的香兰素会迁移到卷烟纸中,而乙基香兰素主要转...     

新型稀奶油-大豆分离蛋白香基的风味形成研究

该研究利用两步酶法结合发酵制备出一款新型稀奶油-大豆分离蛋白复合风味香基。克服了目前单一酶法、发酵法、一步酶法结合发酵法所制备的奶味香基产香周期长，易产生刺激性风味、菌酶存在拮抗作用等局限性。同时，使用大豆分离蛋白部分替代稀奶油，构建全新复合底物体系，丰富稀奶油蛋白源营养与风味物质并降低了香基生产成本。该研究对香基经菌酶不同处理的主要代谢物和风味物质的变化进行测定，分析了两者的潜在关系，探讨了菌酶对香基风味形成的不同作用。结果表明，干酪乳杆菌和蛋白酶共同添加时，促进了苯甲醛、乙酸、3-羟基-2-丁酮、2,3-丁二酮、糠醛和2-戊基呋喃的形成，而先蛋白酶后脂肪酶的处理则有利于丁酸、己酸、辛酸、癸酸、9-癸烯酸、十二酸、辛酸乙酯和δ-十二内酯的积累。     

HbNO在发酵灌肠制品中的应用研究

使用猪血和NaNO2制备亚硝基血红蛋白(HbNO),将其代替助色剂NaNO2应用于香肠中,能有效降低香肠中NO2残留量,并提高其铁的含量。进一步添加产香发酵菌和天然抗氧化剂,在增进香肠风味,消除肉毒中毒隐患及抗氧化保质方面起控制作用,从而实现其低硝、高铁、增香、保质、安全的目标。     

奶啤的研制

以牛奶、麦芽和酒花为主要原料,通过二次生物发酵研制出具有奶香和啤酒风味的奶啤饮料。通过实验确定奶啤的最佳配方及生产工艺流程并对奶啤的稳定性进行探讨,从而研制出即有啤酒的低酒精度、泡沫丰富和适度的二氧化碳,又具有酸乳饮料的酸甜可口、营养全面的奶啤饮料。     

生物法制备奶味香精的研究进展

奶味香精,是一种具有奶香香气的新型食品添加剂.文章综述了奶味香精中主要风味化合物的来源以及生物法制备奶味香精的途径,并对奶味香精的前景进行了展望.     

Jamie Oliver欢聚秋之韵——番茄香肠意面

这几道香浓美味的菜是为你的秋日聚会特别推荐的：先来一道香滑诱人的奶香南瓜汤，再来一道味道十足的番茄香肠意面，最后，用金秋的硕果采结束这次愉快的晚餐。谁会不心动呢？”     

基于感官导向的香荚兰特征风味物质分析及重构

采用顶空固相微萃取结合气相色谱-质谱联用法分析香荚兰提取物挥发性香气成分组成。以感官为导向,利用嗅觉阈值、香气活性值（odour active value,OAV）及香气重组实验研究香荚兰提取物特征风味物质并进行重构。结果表明,香荚兰提取物中共检出83种香气成分,与香荚兰提取物特征风味密切相关的奶香、甜香、酸香、膏香、焦香、豆香和辛香香韵特征成分共有34种。基于OAV判断香兰素、4-(乙氧基甲基)苯酚、愈创木酚、乙酸、4-乙烯基愈创木酚、香草醇乙醚等14种化合物为香荚兰提取物特征风味的关键贡献成分。14种关键贡献成分的重组样品具有香荚兰样的奶香、甜香、烟熏香和酸香,香荚兰特征香气风格辨识度明显,与香荚兰特征风味天然香原料的感官相似度达92.33%。香兰素、4-(乙氧基甲基)苯酚、愈创木酚、乙酸、4-乙烯基愈创木酚、香草醇乙醚、乳酸乙酯等14种化合物被鉴定为香荚兰特征风味物质,可作为香荚兰特征风味天然香原料质控的关键指标,也可为复配重构香荚兰特征风味添加剂提供物质基础。     

复合酶水解奶油制备天然奶味香基的工艺研究

采用脂肪酶和蛋白酶组成的复合酶制剂作为催化剂,酶解奶油制备天然奶味香基。结果表明,当酶解温度为40 ℃,酶解时间7 h,奶油浓度为95%,酶添加量为1.0%,乳清液添加量为25%,脂肪酶A与复合蛋白酶比例为2∶1时,所制得的天然奶味香基为甜奶香型,其香气自然、柔和、圆润,此时所产奶味香基的酸价在18～21 mg/g之间,感官评分值可达到70以上。     

GC-MS分析天然奶味香精的致香成分

利用气相色谱-质谱联用技术对两种天然奶味香精中的致香成分进行了分析鉴定,结合计算机质谱图库,确定两种香精中的主要致香成分为内酯类、中短链脂肪酸、酯类、噻唑类等化合物.两种香精的香气不同,各化合物之间的组成及含量不同,但含量最高的都为δ-癸内酯.利用确定的GC-MS条件对无水奶油的酶解物进行了分析,鉴定了贡献较大的脂肪酸组成及微量物质.     

乳及其制品中风味物质的研究进展

乳尤其是发酵乳中的风味物质种类繁多,包括非挥发性酸、挥发酸、羰基化合物以及蛋白、脂肪和乳糖等的分解物。由于加工过程中微生物和理化的原因,容易使乳制品产生不良风味。通过加入抗氧化剂等添加剂、加强杀菌措施、控制原料奶的品质和环境条件来控制风味的变化,提高其品质。     

脂肪酶水解乳脂制备天然奶味香基的研究

选取了5种微生物来源的脂肪酶对乳脂进行酶解。结合香气评定,筛选出了对乳脂中短链脂肪酸特异性最强、水解物香气评分最高的lipase MER为实验用酶。研究了lipase MER水解乳脂的工艺条件,得出其水解乳脂适宜温度为40℃、pH值为6.5,底物浓度为50%。经焙烤评定lipase MER水解乳脂制得的水解物奶香柔和、自然。可作为调配天然奶味香精的香基。     

热处理引起牛乳风味变化的研究进展

热处理是各种乳制品生产过程中不可或缺的工艺步骤,热处理过程中乳体系的风味组成会发生变化。近年来,不同乳制品的风味日益引起国内外学者和消费者的关注。本文介绍了新鲜牛乳中风味物质的基本特性、风味物质的形成途径及乳中异味的来源;探讨了热处理过程中主要风味前体发生的变化;阐述了加热、浓缩、干燥等热处理对乳制品中风味组成的影响及其对储藏过程中风味变化的作用,为乳制品加工中热处理的潜在影响提供理论参考。     

巧克力风味牛奶的研制与开发

近年来市场上出现的巧克力牛奶一般都是用巧克力加牛奶直接配制而成的,由于巧克力热量高,易导致肥胖、高血脂等疾病,因此在市场上的销售受到了一定的限制。本课题通过选用巧克力香精替代巧克力,以鲜牛奶为主要原料,选用L9(33)正交表,通过正交实验筛选最佳配方。试验结果表明鲜牛奶85.0%,复合稳定剂0.16%,巧克力香精0.07%,食用色素0.106%,AK糖0.02%,可可粉0.4%,白砂糖2.0%。产品经分析检测符合国家质量卫生标准,口感细腻,巧克力风味浓郁,奶香突出,色泽诱人,是一种非常有发展前途的新型风味牛奶。     

The effect of vitamin concentrates on the flavor of pasteurized fluid milk

Fluid milk consumption in the United States continues to decline. As a result, the level of dietary vitamin D provided by fluid milk in the United States diet has also declined. Undesirable flavor(s)/off flavor(s) in fluid milk can negatively affect milk consumption and consumer product acceptability. The objectives of this study were to identify aroma-active compounds in vitamin concentrates used to fortify fluid milk, and to determine the influence of vitamin A and D fortification on the flavor of milk. The aroma profiles of 14 commercial vitamin concentrates (vitamins A and D), in both oil-soluble and water-dispersible forms, were evaluated by sensory and instrumental volatile compound analyses. Orthonasal thresholds were determined for 8 key aroma-active compounds in skim and whole milk. Six representative vitamin concentrates were selected to fortify skim and 2% fat pasteurized milks (vitamin A at 1,500–3,000 IU/qt, vitamin D at 200–1,200 IU/qt, vitamin A and D at 1,000/200–6,000/1,200 IU/qt). Pasteurized milks were evaluated by sensory and instrumental volatile compound analyses and by consumers. Fat content, vitamin content, and fat globule particle size were also determined. The entire experiment was done in duplicate. Water-dispersible vitamin concentrates had overall higher aroma intensities and more detected aroma-active compounds than oil-soluble vitamin concentrates. Trained panelists and consumers were able to detect flavor differences between skim milks fortified with water-dispersible vitamin A or vitamin A and D, and unfortified skim milks. Consumers were unable to detect flavor differences in oil-soluble fortified milks, but trained panelists documented a faint carrot flavor in oil-soluble fortified skim milks at higher vitamin A concentrations (3,000–6,000 IU). No differences were detected in skim milks fortified with vitamin D, and no differences were detected in any 2% milk. These results demonstrate that vitamin concentrates may contribute to off flavor(s) in fluid milk, especially in skim milk fortified with water-dispersible vitamin concentrates.     

Flavor and flavor chemistry differences among milks processed by high-temperature,short-time pasteurization or ultra-pasteurization

Typical high-temperature, short-time (HTST) pasteurization encompasses a lower heat treatment and shorter refrigerated shelf life compared with ultra-pasteurization (UP) achieved by direct steam injection (DSI-UP) or indirect heat (IND-UP). A greater understanding of the effect of different heat treatments on flavor and flavor chemistry of milk is required to characterize, understand, and identify the sources of flavors. The objective of this study was to determine the differences in the flavor and volatile compound profiles of milk subjected to HTST, DSI-UP, or IND-UP using sensory and instrumental techniques. Raw skim and raw standardized 2% fat milks (50 L each) were processed in triplicate and pasteurized at 78°C for 15 s (HTST) or 140°C for 2.3 s by DSI-UP or IND-UP. Milks were cooled and stored at 4°C, then analyzed at d 0, 3, 7, and 14. Sensory attributes were determined using a trained panel, and aroma active compounds were evaluated by solid-phase micro-extraction or stir bar sorptive extraction followed by gas chromatography-mass spectrometry, gas chromatography-olfactometry, and gas chromatography-triple quad mass spectrometry. The UP milks had distinct cooked and sulfur flavors compared with HTST milks. The HTST milks had less diversity in aroma active compounds compared with UP milks. Flavor intensity of all milks decreased by d 14 of storage. Aroma active compound profiles were affected by heat treatment and storage time in both skim and 2% milk. High-impact aroma active compounds were hydrogen sulfide, dimethyl trisulfide, and methional in DSI-UP and 2 and 3-methylbutanal, furfural, 2-heptanone, 2-acetyl-1-pyrroline, 2-aminoacetophenone, benzaldehyde, and dimethyl sulfide in IND-UP. These results provide a foundation knowledge of the effect of heat treatments on flavor development and differences in sensory quality of UP milks.     

巧克力风味牛奶的研制与开发

通过选用巧克力香精替代巧克力,以鲜牛奶为主要原料,选用L9(33)正交表,通过正交实验筛选最佳配方。结果表明,鲜牛奶85.0%,复合稳定剂0.16%,巧克力香精0.07%,食用色素0.106%,AK糖0.02%,可可粉0.4%,白砂糖2.0%(均为质量分数,下同)。产品经分析检测符合国家质量卫生标准,口感细腻,巧克力风味浓郁,奶香突出,色泽诱人,是一种很有发展前途的风味牛奶。