液熏鲟鱼片生产工艺优化与品质影响分析

研究了液熏鲟鱼片的加工工艺及其对品质的影响,以期为液熏鲟鱼片产品开发提供理论指导。从烟熏液种类、烟熏液质量分数、液熏时间和干燥时间4个方面对烟熏鲟鱼片的工艺进行了优化。结果表明,山楂核烟熏香味料Ⅱ号,烟熏液质量分数5%,液熏3 h,85℃干燥2 h处理条件下液熏鲟鱼片具有浓郁而宜人的烟熏风味。进一步从微生物、含水率、粗蛋白、脂肪、盐分、有效酸度(p H值)、挥发性盐基氮(TVB-N)、苯并芘和挥发性风味成分方面评价鱼片液熏干燥后品质的变化,结果表明鲟鱼片总菌数由液熏前2×10~3CFU/g减少为液熏后5×10~2CFU/g,酚类物质相对含量由液熏前0.89%升高到液熏后8.62%。鲟鱼片液熏干燥后含水率减少而粗蛋白、粗脂肪含量升高,产品中未检出致病菌,苯并芘含量(质量比)仅为0.22μg/kg。以上研究结果表明经本试验优化工艺制得的液熏鲟鱼片产品微生物及苯并芘含量符合相关标准,且风味良好,适宜进行大规模生产和推广。     

汶上芦花鸡和济宁百日鸡母鸡的肌肉营养成分及风味的比较

本试验旨在研究刚开产的汶上芦花鸡和济宁百日鸡母鸡肌肉的营养成分和挥发性风味物质.选择1日龄汶上芦花鸡和济宁百日鸡母鸡各200只,随机分为4个重复,每个重复50只鸡,在统一的营养水平和饲养管理方式下进行饲养,每个重复随机选取4只于150日龄屠宰,分析其肌肉品质、肌肉中挥发性风味物质的含量.结果表明:汶上芦花鸡和济宁百日鸡的胸肌中肌苷酸含量均显著高于腿肌(P<0.05);汶上芦花鸡和济宁百日鸡的腿肌、胸肌的氨基酸组成中EAA/TAA在40%左右,EAA/NEAA均在65%以上,必需氨基酸评分中,汶上芦花鸡和济宁百日鸡的腿肌、胸肌中的苏氨酸、缬氨酸、异亮氨酸、亮氨酸、赖氨酸和汶上芦花鸡的蛋氨酸等必需氨基酸评分均高于理想评分,说明这2个品种均具有优秀的蛋白质水平和较高的营养价值;汶上芦花鸡和济宁百日鸡的腿肌均含有20种脂肪酸,胸肌均含有17种脂肪酸,其中,济宁百日鸡的多不饱和脂肪酸总量(PUFA)显著高于汶上芦花鸡(P<0.05),而单不饱和脂肪酸总量(MUFA)显著低于汶上芦花鸡(P<0.05),表明济宁百日鸡的营养价值要高于汶上芦花鸡,但肉品质上易酸败变质;汶上芦花鸡和济宁百日鸡的腿肌、胸肌中挥发性风味物质组成差别较大,且均以烷烃类、醇类、醛类和酮类化合物为主.由此可见,汶上芦花鸡和济宁百日鸡母鸡均具有较高的营养价值和可口的风味.     

木酢液对2种类型蔬菜感官品质和质量安全的效应

为了研究木酢液对蔬菜感官品质和质量安全的影响,对番茄和大白菜施用不同浓度的木酢液进行对照试验。结果表明：经低浓度500倍木酢液处理后,番茄体内番茄红素含量、Vc含量以及糖酸比均显著增加;大白菜体内可溶性糖含量、可溶性蛋白含量和Vc含量提高明显。而经高浓度300倍木酢液处理后,番茄中番茄红素含量减少,其他指标无显著变化;大白菜除叶绿素含量显著升高外,其他指标变化不显著或降低。此外,木酢液处理显著降低了番茄和大白菜的亚硝酸盐水平,并且没有明显增加重金属的富集程度。这说明适宜浓度的木酢液可以改善蔬菜品质,并能有效保障2类蔬菜的食品质量安全。     

同时蒸馏萃取和固相微萃取对鸡肉汤挥发性风味物质萃取效果的比较

用同时蒸馏萃取法(SDE)和固相微萃取技术(SPME)分别萃取AA肉鸡肉汤的挥发性风味物质,再经过气相色谱和质谱联用技术(GC/MS)进行分析,共检测出87种化合物,包括醛、醇、酮、酸、烃、酯、酚、含N化合物、含S化合物以及含C l化合物等。结果表明采用SDE法对高沸点化合物的萃取效果较好,同时由于萃取温度较高,会产生大量的后续反应产物;固相微萃取法对低沸点化合物的萃取效果较好,特别是对肉汤风味作用极大的醛类萃取效果极佳。     

畜禽肌肉肌苷酸研究进展

文章综述了畜禽肌肉呈味物质肌苷酸的研究现状、呈味机理、代谢途径和影响因素,提出了现阶段肌苷酸研究过程中存在的问题并对未来的研究方向进行了展望,以期为目前动物营养工作者在畜禽风味品质方面的研究提供借鉴与参考。     

固相微萃取分析海南地区黑胡椒粉风味成分

采用固相微萃取采集海南地区黑胡椒粉的挥发性成分,用气相色谱-质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,共鉴定出α-蒎烯、β-蒎烯、3-蒈烯、柠檬烯、异松油烯和石竹烯等15种化合物。     

Geosmin and Off-Flavor in Nile Tilapia (Oreochromis niloticus)

Abstract

The concentration of geosmin (1,10-trans-dimethyl-trans-9-decaol) in fresh tilapia were analyzed by applying high-vacuum distillation, extraction and gas chromatography techniques. The distribution of geosmin in the fish was determined by examining tissues from various parts of tilapia, along with the rates of geosmin absorption and purging. Analysis showed that when geosmin was added to fish flesh at concentrations ranging from 2.8 to 390 μg per kg of flesh, the rate of recovery was 51 to 89%. Sensory evaluation detected muddy flavor in freshwater tilapia with geosmin content ranging from 7.55 to 9.85 μg/kg of fish flesh. However, panelists failed to detect muddy flavor in brackish water tilapia that contained geosmin only in the range of 1.5 to 2.6 μg/kg. Among various tissues of the fish, the intestines contained the highest geosmin concentration, and appeared in descending order in the abdominal, skin and muscle tissues. After holding for 2 h in water with 5 and 50 μg/l geosmin, tilapia absorbed 17.6 and 42.2 μg/kg geosmin in the flesh, respectively. Holding the fish over longer periods in water with higher geosmin content resulted in a greater amount of absorption. In contrast, transferring muddy-flavored fish to static clean water purged geosmin from the fish but it required at least 16 days to eliminate the muddy flavor.     

BOOK REVIEW

No abstract available for this article.     

Monitoring Quality of Packaged Pacific Ocean Perch (Sebastes alutus) in Storage

Pacific ocean perch stored under vacuum, 100% CO₂ or air at -3°C and 3°C was subjected to sensory, trimethylamine (TMA), color, microbial and volatile analyses. Unpleasant sensory attributes, TMA and microbial content were negatively correlated to overall quality, and Hunter 'L' value increased with storage time. Principal factor analysis of sensory data resulted in three factors that accounted for 71% of the variance, with factor 1 (53%) mainly related to poor quality attributes. Volatiles analyzed by the dynamic headspace technique included alkanes, alkenes, aldehydes, aromatics and alcohols. Canonical variate analysis on volatile compounds separated excellent and poor quality fish samples, while good and medium samples were grouped together.     

脱水青胡椒粉风味成分的研究

采用固相微萃取采集40目、60目和80目3种不同脱水青胡椒粉的挥发性成分,用气相色谱-质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,共鉴定出石竹烯(18.43%~30.07%)、3-蒈烯(17.32%~21.84%)、β-派烯(7.61%~15.21%)、柠檬烯(3.28%~14.77%)、α-派烯(4.39%~9.61%)、石竹烯氧化物(2.13%~6.20%)、δ-榄香烯(3.32%~4.96%)和可巴烯(2.01%~2.63%)等34种化合物,而且脱水青胡椒粉粹程度越大,其挥发性成分中3-蒈烯和可巴烯的含量越大。