Effect of edible oils and oil emulsions on the perception of basic tastes

The intensity of sweet, bitter or astringent tastes is reduced by con-sumption of edible oil or oil emulsions immediately before the inges-tion of test solutions. The basic taste substances were dissolved in 30% aqueous ethanol, flavoured with plant extracts. The time-intensity dependence was influenced similarly. The sensitivity of taste receptors returned to the original value within 15—20 min. Intensities of acidic or salty tastes were not affected.     

感官评定方法确定麻竹笋苦涩味物质成分及与口感的关系

通过分析测定麻竹笋苦涩味物质含量与感官评定方法确定竹笋苦涩味物质成分及与口感的关系。麻竹鲜笋在100℃纯净水中分别进行0、30、90、150 s和420 s 5个时间梯度水煮处理,并测定煮后笋汤、笋渣的可溶性单宁、草酸和游离苦味氨基酸(Phe、Val、Arg、Met和Leu)含量,感官评定小组对其涩味、苦味强度评定,并通过对食品级草酸、单宁标准样品配制的不同质量浓度溶液进行苦涩味感官评定,建立单宁、草酸、单宁和草酸混合液的质量浓度与滋味强度的特征曲线函数。结果表明,影响麻竹笋苦涩味的主要物质是可溶性单宁,竹笋苦味和涩味均与单宁含量呈极显著关系,相关系数分别达0.896和0.867;竹笋涩味与草酸含量呈显著关系,相关系数为0.448,而竹笋苦味与草酸含量无显著关系;竹笋苦涩味与游离苦味氨基酸含量均无显著关系。利用单宁特征曲线函数对竹笋苦涩味偏重的成因进行了分析,对9个笋渣、笋汤的分析结果表明,单宁特征曲线函数对竹笋涩味的解释程度达60.6%~136.4%,对竹笋苦味的解释程度达63.4%~132.0%,较高的可溶性单宁含量是引起麻竹笋苦涩味偏重的主要原因。     

Undesirable sensory properties of the dried pea (Pisum sativum). The rôle of saponins

The rôle of saponins in the undesirable sensory properties of the dried pea P sativum is reported. The sensory properties of isolated soyasaponin I are defined and described as bitter, astringent and metallic. The distribution of saponin in various air-classified pea flour fractions shows that the protein-rich fraction may contain sufficient saponin to cause undesirable tastes.     

加热预处理对大豆胚芽风味及其异黄酮存在形式的影响

大豆胚芽含有大量异黄酮化合物,天然异黄酮存在形式主要丙二酰型糖苷,此类异黄酮化合物是大豆胚芽的苦涩、豆腥味的主要呈味物质。研究显示采用加热处理可较大程度地降低大豆胚芽的苦涩味,从而改善胚芽的风味。采用HPLC分析显示,加热处理可使丙二酰型异黄酮糖苷转换为乙酰型糖苷,甚至糖苷化合物,后者的呈味显著低于丙二酰型异黄酮糖苷化合物。     

Masking of Soy Protein Flavor by Tomato Sauce

Flavor interaction in a model system consisting of 5% (w/w) soy protein in a series of tomato sauces containing 55–100% commercial tomato paste was evaluated by six trained panelists. Intensities of the tomato flavors were found to increase with tomato concentration. The combination of the soy and tomato components resulted in the repression of the bitter, harsh and astringent tomato flavors, and significantly reduced the overall flavor and acidic intensities of the tomato component. Individual odors and flavors of the soy protein became indistinguishable in soy/tomato mixtures. There was a substantial reduction in the overall soy odor, flavor and aftertaste with the increase in tomato concentration.     

尤溪苦茶资源苦涩味物质测定与分析

采用分光光度法和高效液相色谱法,对33?份尤溪苦茶资源的花青素、总黄酮、生物碱组分、儿茶素组分等显苦涩味物质的生化成分进行测定。结果表明,其物质成分特征指标均具有一定差异,20?个指标变异系数在9.74%～73.08%之间,说明尤溪苦茶苦涩味生化成分存在丰富的多样性和变异性。与4?份对照茶树相比,发现尤溪苦茶在花青素、咖啡碱、可可碱、茶碱、表没食子儿茶素没食子酸酯、儿茶素总量和酯型儿茶素的均值均高于对照,表明尤溪苦茶苦涩味突出的原因为高含量的花青素、咖啡碱和儿茶素及其相互协同作用。据此筛选出花青素含量特异资源8?份、高咖啡碱资源1?份、可可碱特异资源1?份以及高表没食子儿茶素没食子酸酯资源21?份,为苦茶的杂交育种、创新加工、功能性成分开发与次生代谢机理的相关研究提供良好的材料基础。     

几种特色瓜的腌制技术(下)

为增加腌制瓜的品种,该文介绍了3种特色瓜的腌制方法。素火腿是选用经霜的老倭瓜,灌满陈年特抽酱油,封盖,悬挂,至次年农历4、5月份取下。入蒸笼蒸熟后切片制成。色酱红,味甘鲜戋;酱姜丝癞葡萄是选用未成熟的癞葡萄经切制、热烫、腌制、加生姜丝压卤、香液浸溃、酱渍和翻袋等工序制成的,色泽金黄或酱红,嫩脆鲜甜,香气独特;酱瓠瓜是将嫩瓠瓜清洗后。经腌渍、压卤、酱渍和翻缸等工序制成的,呈酱红或金黄色,酱替浓郁．鲜甜嫩脆。     

烘焙温度对可可豆苦涩味的影响

对不同烘焙温度下的可可豆进行致苦涩味物质分离分析,基于感官评价和相对香味活力值的概念筛选出参与可可豆苦涩味形成的主要组分,并结合热裂解-气质联用技术研究烘焙温度上升时可可豆挥发性物质的变化规律。结果表明:(1)可可豆提取物苦涩味流分共检测出55种挥发性成分,其中醇类7种,酸类5种,酯类9种,醛类8种,酮类6种,烯烃类2种;(2)致苦涩味的关键组分为2-甲基丙醛、2-甲氧基苯酚、2-庚醇、戊醛、2-戊酮、苯甲醛、2,5-二甲基-4-羟基-3(2H)-呋喃酮,修饰组分为3-甲基丁醇、2,3-二甲基-5-乙基吡嗪、2,5-二甲基吡嗪、2,3-二甲基吡嗪、2-甲基丙醇;(3) 130~135℃为降低可可豆苦涩味的最佳烘焙温度。     

樱桃酒感官评价与电子舌感官分析的相关性研究

对五种不同樱桃酒的感官属性(酸、甜、苦、涩)进行了感官评价和电子舌指纹分析,利用主成分(PCA)与判别因子(DFA)分析对电子舌区分樱桃酒的能力进行了评价,并通过PCA、偏最小二乘法(PLSR)将感官评价结果与电子舌7根传感器(ZZ、BA、BB、CA、GA、HA、JB)响应相关联。结果表明,电子舌指纹分析系统对樱桃酒具有较好的区分辨别能力,传感器JB与酸味,传感器HA、CA与甜味,传感器ZZ与涩、苦味具有较高的相关性。     

毛霉蛋白酶的制备及其酶解产物的分析

应用ＨＰＬＣ法分析了毛霉蛋白酶的酶解产物，并应用质谱仪测定了酶解产物的分子量，结果表明：该蛋白酶在４０℃ＰＨ７．３的条件下催化大豆分离蛋白水解５ｈ。     

Development of soy-based bread with acceptable sensory properties

Consumption of soy protein has been associated with benefits related to numerous areas of health. Due to the widespread consumption of bread, one means of contributing to the health of individuals is through the incorporation of soy protein into bread. To this end, soy flour (SF) or soy protein isolates (SPIs) in 20% and 12% substitution levels, respectively, were added to flour during bread manufacture. The developed breads were tested using a consumer panel for acceptability, using a refined white bread as a control. These data were compared to attribute intensity data collected by the trained panel to identify specific flavor and texture characteristics affecting liking. The sensory profile of the 20% SF bread was acceptable and comparable to the control bread, despite a significantly stronger beany flavor. No significant differences in sensory properties of the SF and control breads were detected by the trained panel for many sensory attributes. The SPI bread, however, had a sensory profile that was significantly more firm, dense, sour, beany, bitter, and astringent with a strong aftertaste in comparison to the wheat control bread. Consumer liking scores for the SPI bread was significantly lower than the liking of the control and the SF added bread. PRACTICAL APPLICATION: Many soy-enriched foods, while contributing positively to health, are considered unacceptable by consumers. This is due to negative sensory properties, such as beany, painty, and astringent notes, often perceived by consumers. This study provides information on the level of SF that can be included in bread in an amount that does not detract from consumer acceptability. This level also allows for a Food and Drug Administration (FDA) health claim to be made.     

Sogurt, a Yogurt-like Soybean Product: Development and Properties

Two sogurt products were prepared by fermenting a formulation containing soymilk, 0.15% calcium acetate, 0.5% gelatin, and lactose (0 or 2%) with Lactobacillus casei and Streptococcus thermophilus. Commercial plain yogurt was used as a control. Sogurts were evaluated for aroma, taste, texture, titratable acidity, pH, and color. Sogurts had beany and raisin aromas, more bitter and astringent tastes than yogurt, and slightly sandy mouth- feel. Sogurts and yogurt did not differ (P < 0.05) in intensity of butter aroma. Sogurt with lactose did not differ (P < 0.05) from yogurt in acidity. Sogurts were yellower and firmer than yogurt.     

不同脱苦涩处理刺梨果汁风味品质分析

以刺梨果汁为原料,采用感官评定方法结合电子舌技术,探讨不同苦涩味的脱除方法对刺梨果汁风味品质的影响,并确定最佳脱除条件。结果表明：刺梨汁整体味感以酸味、涩味和苦味为主。添加剂组合方法脱除刺梨汁苦涩味效果明显优于单一方法,其最佳脱苦涩味的方法为添加质量分数0.12%单宁酶和质量分数0.015%三氯蔗糖,该方法处理的刺梨汁感官评定分值最高、结果最佳、口感适宜、苦涩味最轻,经电子舌检测在苦味和涩味2 个传感器上的响应值最小。在食品风味评价中,应将电子舌技术结合传统感官评定方法进行分析,利于获得更准确、可靠的结论。     

氨肽酶脱苦效果的研究

目的研究从豆腐乳中筛选到的一种枯草芽孢杆菌所产的氨肽酶脱除大豆蛋白质水解物苦味的效果。方法用高效液相色谱法和感官评定。结果1%的大豆蛋白质溶液经胰蛋白酶水解,水解液呈苦味,添加氨肽酶可较好地脱苦,水解液中游离氨基酸的总量增加了28.8%,疏水氨基酸的量也明显增加。结论枯草芽孢杆菌氨肽酶具有较好的脱苦效果。     

酵母抽提物的不同添加方式对藜麦膨化粉感官品质、味觉特性和挥发性风味物质的影响

分别将酵母抽提物(YE)在挤压膨化前后添加到藜麦粉中得到YE藜麦膨化粉和YE+藜麦膨化粉,利用味觉分析系统、GC-MS等方法分析藜麦膨化粉、YE藜麦膨化粉和YE+藜麦膨化粉的味觉特性及挥发性风味物质,并进行感官评价.结果 表明:与藜麦膨化粉相比,YE+藜麦膨化粉的香味浓郁,感官评分较高,苦味、涩味、苦味回味、涩味回味显...     

氨肽酶脱苦效果的研究

目的研究从豆腐乳中筛选到的一种枯草芽孢杆菌所产的氨肽酶脱除大豆蛋白质水解物苦味的效果。方法用高效液相色谱法和感官评定。结果1％的大豆蛋白质溶液经胰蛋白酶水解，水解液呈苦味，添加氨肽酶可较好地脱苦，水解液中游离氨基酸的总量增加了28．8％，疏水氨基酸的量也明显增加。结论枯草芽孢杆菌氨肽酶具有较好的脱苦效果。     

Size-Exclusion HPLC Separation of Bitter and Astringent Fractions from Cheddar Cheese Made with Added Lactobacillus Strains to Accelerate Ripening

Lactobacillus strains were added as an adjunct to the regular lactic starter in Cheddar cheese manufacture in order to accelerate ripening. Microbial cheese proteolysis resulted in the release of free amino acids which were extracted with the astringent and bitter fractions and separated by size-exclusion and reversed-phase HPLC chromatography. Lactobacillus strains generally increased the degree of proteolysis. L. plantarum and L. brevis produced off-flavors possibly due to an accumulation of medium-size peptides. The control cheese (without lactobacilli) had the most peptides with a mean molecular- weight of < 1000 daltons and had a flavor described as slightly bitter. Addition of L. casei-casei L2A accelerated ripening and yielded a well-aged Cheddar cheese without any bitterness even after 7 months at 6°C.     

激活酿造提高酱油中氨基酸总量及优化氨基酸比例

分析激活酿造工艺和普通浇淋工艺得到的酱油氨基酸组成,结果表明,激活酿造得到的酱油游离氨基酸的总量为35.27mg/g,比普通工艺高101.37%,呈鲜味的谷氨酸和天门冬氨酸所占比例均高于对照,其中谷氨酸占酱油全部游离氨基酸的23.87%,而普通浇淋工艺的谷氨酸为全部游离氨基酸的11.47%,激活酿造酱油中呈苦味的氨基酸所占比例大部分低于对照.实验从数据上证明了激活酿造酱油质量要优于普通工艺所得到的酱油.