中温发酵酸乳的游离氨基酸、脂肪酸和感官特性的研究

采用正交设计试验研究了球杆菌比例、全脂乳浓度、发酵终点以及蔗糖添加量对中温发酵酸乳的风味和游离氨基酸、脂肪酸含量的影响。以9个不同的酸乳工艺配方为研究对象,采用主成分分析法(PCA)研究了不同样品的感官特征和游离氨基酸,脂肪酸含量。采用偏最小二乘回归分析法(PLSR)研究了感官结果和仪器测定结果的相关性。结果表明,球杆菌比例和全脂乳浓度是影响奶香味酸味、游离氨基酸量,脂肪酸量的重要因素。偏最小二乘回归分析表明酸乳气味与脂肪酸相关性较强,而风味和余味与游离氨基酸相关性强。     

搅拌型酸奶感官评价与仪器测定间的相关性研究

选取8种市售搅拌型酸奶,对其挥发性物质、非挥发性物质和质构进行全面测定,并同时进行感官评价。分析各检测指标与感官指标之间的相关关系,建立检测指标与感官指标的逐步回归模型。结果显示,糖类物质中蔗糖和半乳糖与甜味的对应性最高;丙酮、2-丁酮、D-(+)-葡萄糖醛酸γ内酯、乙酸乙酯与酸奶的果香味相关;2,3-丁二酮赋予酸奶奶香味;二甲基二硫醚和二甲基硫醚分别是酸奶蒸煮味与硫味的主要来源。口中稠度、吞咽力度、拉丝感和粉感与全质构分析(texture profile analysis,TPA)模式中对应指标间存在极显著的相关性(P<0.01)。逐步回归分析显示,可以使用蔗糖、半乳糖、丙酮、乙酸乙酯、二甲基二硫醚、二甲基硫醚、稠度与胶黏性的测量值代替感官评价。     

Chemical, Microbiological and Sensory Properties of Plain Nonfat Yogurt

Chemical and microbiological properties of plain nonfat yogurt were determined after 2, 6 and 12 days refrigerated storage. Sensory properties were determined after 6 days storage. Viable culture bacteria concentrations ranged from 140 to 8,000 × 10⁶/g and ratios of lactobacillus to streptococcus ranged from 0.18 to 15.4. Chemical criteria used to characterize products included: pH, titratable acidity, lactic and four other organic acids and lactose by HPLC, and 23 major volatile organic compounds by dynamic headspace analysis. Lactic acid concentrations ranged from 7.5 to 9.9 mg/g. Major flavor volatiles in all yogurts included: acetaldehyde, heptane, acetone, diacetyl, and benzothiazole. Untrained sensory panels showed differences for flavor, aroma and acceptability.     

Improved Acid, Flavor and Volatile Compound Production in a High Protein and Fiber Soymilk Yogurt-like Product

The effects of added caseinate (CAS), casein hydrolyzate (CASHY) and whey protein hydrolyzate (WPHY) on acid, flavor and volatile compound production in a high protein and fiber soymilk yogurt-like product were studied. High protein and fiber soymilk, produced by blending soaked, boiled and dehulled soybeans with Swiss cheese whey ultrafiltration permeate, was fermented with a mixed S. thermophilus and L. bulgaricus yogurt culture. The concentrations of lactic acid, key volatile compounds, i.e., acetaldehyde, acetone, and diacetyl, and the flavor and texture of the resulting soymilk based yogurt formulated with added CAS or CASHY were comparable to those in a milk yogurt control.     

FP/QDA法在无糖酸奶感官性质分析中的比较

分别利用Flash Profile(FP)法和定量描述分析(QDA)法对4种市售无糖酸奶进行了描述性分析.FP法中10名未经训练的和QDA法中6名经过培训的感官评价员分别建立感官描述词,对所有样品进行感官特征评价,并对得到的数据进行了方差分析、主成分分析和系统聚类分析.结果 表明,两种方法都能将样品合理分类,但所分类别...     

不同发酵剂生产的酸奶感官评定和TPA质构分析

质构剖面分析法(Texture Profile Analysis,TPA)是食品质构分析的重要方法。该文通过质构剖面分析法研究了不同发酵剂对酸奶质构的影响,并和感观评价方法进行了比较。结果表明,不同发酵剂对酸奶的硬度和胶粘性影响很大,单一保加利亚乳杆菌和嗜热链球菌生产的酸奶硬度和胶粘性最高。两菌混合硬度和胶粘性明显降低,但内聚性最高。嗜热链球菌可明显增加产品粘度。TPA分析和感观评价中硬度参数值非常吻合,TPA分析中的胶粘性和感观评价中的喉咙口滞留度有较好的关联性。两菌混合后提高杆菌比例生产的酸奶综合感观评价值最高。     

Investigating Influence of pH and Parts on Sensory Characteristics and Volatile Components in Boiled Squid Using Experimental Designs

ABSTRACT: The aroma property of boiled squid was quantitatively described using 10 sensory attributes. From screening experiments based on a Plackett-Burman design, pH and parts of squid were selected as significant factors for generating the "cooked squid" aroma. Squid samples prepared according to a 3-level full-factorial design for pH and parts showed that "sweet,""roasted shrimp,""cooked fish," and "cooked squid" scores were higher in both muscle and muscle with skin at pH 6.5. Response surface models calculated for each of the attributes showed how pH and parts influenced their strength. Partial least squares regression analysis applied to the sensory and GC-MS data revealed that every attribute could be predictable (R²≥ 0.956) using a small number of informative peaks.     

Sensory Characteristics of Selected Species of Freshwater Fish in Retail Distribution

Flavor and texture profiles of the cooked flesh of selected freshwater fish in retail distribution were developed by a highly trained sensory panel. The intensity of a variety of flavor, aftertaste, and texture properties was characterized for each fish, including order of appearance for flavor characteristics. These data provide a first examination of the sensory properties of a variety of freshwater fish available to the consumer. A variety of species, including tilapia and hybrid bass, had overall fish-like flavor and texture, but also had some properties similar to white meats, such as chicken. Catfish was earthier, softer, and more gelatinous than most other freshwater fish studied.     

中国黄酒风味感官特征及其风味轮的构建

首次对中国黄酒的风味轮进行绘制,由国家黄酒评委组成的品评小组结合消费者品评小组,对6种不同类型、不同特点的典型黄酒进行风味感官品评,给出黄酒风味感官基本描述语,对描述语进行筛选整理后,参照啤酒、葡萄酒及清酒风味轮,对描述语进行归类,绘制出中国黄酒风味轮。从黄酒风味轮描述语中,运用多元统计方法及ISO 11035感官描述语选择方法的国际标准,选择确定重要的、而且具有典型差异性的味觉和嗅觉描述语：甜味、苦味、涩味、酸味、鲜味、醇香、焦糖香、果香、药香、烟气香、曲香及蜂蜜香12个作为构成黄酒风味轮廓的主要描述语。这些描述语分别经由国家黄酒评委和消费者应用于黄酒描述分析,表明可以表征中国黄酒主要的基本风味感官特征,可用于黄酒基本描述性感官分析。     

Soy Protein Fortification Affects Sensory, Chemical, and Microbiological Properties of Dairy Yogurts

ABSTRACT: Chemical, microbiological, and sensory properties for low fat yogurts fortified with 0,1, 2.5, or 5% soy protein concentrate were determined through 1 mo storage at 5 °C. Yogurts were adjusted to equivalent total solids with nonfat dried milk. Microbiological counts, fermentation time, and final developed acidity were not affected by soy protein. Instrumental viscosity and sensory thickness, soy aroma, and soy flavor increased with soy protein addition (P 0.05). Soy flavor and aroma did not increase with storage time. Yogurt with 5% soy protein was darker, more chalky, and less sweet compared to control yogurt or yogurts with lower concentrations of soy protein (P 0.05). Yogurts with 1 or 2.5% soy protein were most similar to control yogurt.     

Determination of the Sensory Characteristics of Rose Apples Cultivated In Thailand

ABSTRACT:  Rose apple, an economic fruit in Southeast Asia, has potential as an export to western countries where its special attributes are better known to consumers. This research studied sensory characteristics of 8 rose apple varieties using highly trained panels and a defined sensory lexicon. A total of 9 sensory attributes including rose apple identity (ID), fruity, overall sweet, overall sour, bitter, firmness, cohesiveness of mass, astringent, and pulpy residue were present in all rose apple samples, but at different intensities for each variety. Only 5 attributes (floral/perfumy, green, spongy, initial crispness, and sustained crispness) were found in most samples, and were absent in a few samples; and "characteristic" attributes (rose, peel like, spicy, woody, earthy, starchy, and mealy) were detected in only 1 or a few samples. Based on their sensory characteristics, the rose apples being examined were categorized into 3 clusters. Rose apples in this study that are popularly cultivated and consumed including Pet-Num-Ping, Toon-Klao, Tub-Tim-Jun, Pet-Sai-Rung, and Pet-Sam-Pran, all of which were grouped together in cluster 3. They all had a crispy texture, but were very bland in flavor. Ma-Meow (cluster 1) and Num-Dok-Mai and Sa-Rak (cluster 2), which are not as popular, did not have a crispy texture; however, they did have the characteristic flavors of floral/perfumy and rose. The rose apples in cluster 3 might become better accepted if they had the flavor notes similar to those in cluster 1 and 2.