INFLUENCE OF EDUCATION/PROFESSION OF MEXICAN CONSUMERS ON ACCEPTANCE AND PURCHASE INTENT OF CORN TORTILLA

Influence of education/profession of Mexican consumers on acceptance and purchase intent of corn tortillas was evaluated. Two groups of 150 Mexican consumers each (faculty/graduate students [A] versus field laborers [B]) rated sensory acceptability of corn tortillas. Acceptance and purchase intent were rated using a binomial scale. Group B had higher expectations towards corn tortillas as indicated by lower acceptability ratings. Both groups used rollability, resistance-to-tearing, and chewiness to differentiate tortilla samples, but group B paid more attention to these attributes as indicated by higher canonical correlation values. Acceptance was influenced by overall liking for both groups; chewiness and taste were also significant for group B. Purchase intent was influenced by overall liking and taste for both groups, but color for group A, and appearance and chewiness for group B were also critical. This study demonstrated that education/profession of Mexican consumers affected their acceptance and purchase intent of corn tortillas.

PRACTICAL APPLICATIONS

This study revealed that education/profession of Mexican consumers affected acceptance and purchase intent of corn tortillas. Two groups of consumers with different levels of education had different expectation toward tortillas when making purchase decision. Understanding how each consumer segment differently perceives about the tortilla product will give marketers and manufacturers a better direction for developing tortilla products with expected sensory qualities.     

WHAT SENSORY CHARACTERISTICS DRIVE PRODUCT QUALITY? AN ASSESSMENT OF INDIVIDUAL DIFFERENCES

Consumers differ dramatically in their sensory preferences for products. This paper assesses the relative importance of appearance, taste/flavor and texture as characteristics that drive acceptance for a complex pie product. The paper classifies consumers as being driven by one or more sensory attributes in their judgment of product quality. To do so, each consumer's liking rating is regressed against each separate attribute liking. The coefficient (M) of the linear equation "Overall Liking = M (Attribute Liking) + B" measures the relative importance of the sensory attribute as a driver of overall quality.     

Understanding the Jasmine phenotype of rice through metabolite profiling and sensory evaluation

Introduction

Aromatic rices are culturally and economically important for many countries in Asia. Investigation of the volatile compounds emitted by rice during cooking is the key to understanding the flavour of elite aromatic rice varieties.

Objectives

The objectives of this study were to compare Jasmine-type aromatic rices from the Greater Mekong Subregion and Australia in terms of their metabolomics and sensory profiles and to draw out associations between the volatile organic compounds and human sensory perception of rice aroma.

Methods

A set of aromatic rice varieties from South East Asia and Australia, along with non-aromatic controls, was grown in tropical and temperate areas of Australia. Untargeted metabolite profiling of volatile compounds, from the heated rice flour, by static headspace extraction and separation by two dimensional gas chromatography time-of-flight mass spectrometry was performed. Volatile compounds were also assayed in the standard references used in the sensory evaluation and compared to the compounds detected in the headspace of rice.

Results

While 2-acetyl-1-pyrroline (2-AP) was a discriminating compound, we identified several of its structural homologues, and a number of other metabolites that were consistently detected in fragrant Jasmine rice. 2-AP producing rice varieties have different sensory properties and these variations were defined by the discriminating compounds identified in each rice type.

Conclusions

The results of this study are valuable in understanding the aspects of aromatic rice that are important to consumers, and in the identification of compounds that breeding programs can use to select for pleasant aromas, enabling breeding programs to target markets with greater accuracy.

     

水稻品种对美国稻瘟病小种IB-33、IB-45和IE-1的抗性遗传

1995年10月至1997年11月,在美国阿肯色大学水稻研究推广中心,用水稻品种LA110和Jasmine-85与水稻品种Teqing、Katy、Mars、LaGrue和Newbonnet进行不完全双列杂交,对其杂交后代和亲本用美国3个主要稻瘟病菌小种(以下简称小种)IB-33、IB-45和IE-1进行接种鉴定和遗传分析研究.结果表明:亲本LA110、Jasmine-85、Teqing抗所有3个小种.Katy抗小种IB-45和IE-1,感小种IB-33.Mars抗小种IE-1,感小种IB-33和IB-45.LaGrue感所有3个小种.Newbonnet抗小种IB-45,感小种IB-33和IE-1.所有抗病亲本的抗病基因,其F1分别对相应小种呈现显性抗病性.抗病亲本杂交,LA110与Jasmine-85对小种IB-33,LA110与Teqing、Jasmine-85对小种IE-1,及Jasmine-85与Teqing对小种IE-1,是等位的抗病基因.LA110与Teqing对小种IB-33,及Jasmine-85与Teqing对小种IB-33,分别存在三对独立遗传的显性抗病基因.LA110与Teqing、Katy、Newbonnet、Jasmine-85对小种IB-45,Jasmine-85与Teqing、Katy、Newbonnet对小种IB-45,LA110与Katy、Mars对小种IE-1,Jasmine-85与Katy、Mars对小种IE-1,分别存在两对独立遗传的显性抗性基因.抗病亲本LA110或Jasmine-85与感病亲本Mars对小种IB-33,抗病亲本LA110与感病亲本Mars对小种IB-45,具有两对显性互补抗病基因,当两对显性抗病基因同时存在时,表现出抗性.抗病亲本LA110或Jasmine-85与感病亲本Katy、LaGrue、Newbonnet对小种IB-33,抗病亲本LA110与感病亲本LaGrue对小种IB-45,抗病亲本Jasmine-85与感病亲本Mars、LaGrue对小种IB-45,抗病亲本LA110或Jasmine-85与感病亲本LaGrue、Newbonnet对小种IE-1,分别存在一对显性抗病基因.两个亲本正、反交的遗传表现一致.本文也讨论了LA110、Teqing和Jasmine-85三个抗病品种在美国水稻抗病育种中利用的可能性.     

EVALUATION OF RANGE-GRAZED AND CONCENTRATE-FEDBEEF BY A TRAINED SENSORY PANEL, A HOUSEHOLD PANEL AND A LABORATORY TEST MARKET GROUP

A trained sensory panel and a household panel evaluated leaner range-grazed and higher grading concentrate-fed beef for sensory characteristics. The findings were compared to those from a laboratory test market study designed to determine the consumer appeal of branded range-grazed beef when compared to concentrate-fed beef. Broiled steaks from concentrate-fed steers were scored more flavorful, more tender, more juicy and more desirable overall than those from range-grazed steers by the trained sensory panel and by the household panel. In the laboratory test market study steaks from range-grazed steers were nearly equal in acceptance to those from concentrate-fed steers because consumers, although accustomed to concentrate-fed beef in their marketplace, compromised palatability for meat they perceived to be leaner and more healthful.     

Phenotyping of Partial Physiological Resistance to Rice Sheath Blight

Sheath blight, caused by Rhizoctonia solani, is one of the most important rice diseases worldwide especially under irrigated agro‐ecosystems. To date, no rice accession with complete resistance to sheath blight has been reported. However, a number of genotypes with varying levels of resistance have been reported. Twelve genotypes (including mega varieties) viz. Tetep, Jasmine 85, Te‐Qing, Duduruchi, Betichikon, Khatochalani, D‐6766, D‐256, Swarna, Sarju‐52, MTU‐1010 and Samba Mashuri were evaluated for quantitative measurement of partial physiological resistance to sheath blight under controlled conditions using detached tiller method. Three independent experiments, each involving three replications, were conducted. Seven days after inoculation, the following disease variables were measured: number of lesions, lesion length, vertical sheath colonization (VSC) on the tiller, disease severity, relative vertical sheath colonization (RVSC) and survival of the leaf blade. Variation between rice genotypes was observed for all the disease variables. Disease severity and VSC were the two most correlated variables, whereas the number of lesions and mean lesion length were the least correlated variables. The ranking of varieties often differed depending on the disease variable considered. Amongst the genotypes tested, D‐256, Tetep and Jasmin‐85 had the lowest number of lesions and disease severity. Similarly, Tetep and D‐256 showed the lowest levels of RVSC, whilst Jasmine‐85 was found to be intermediate. D‐6766, Samba Mashuri and Betichikon showed the highest levels of disease variables. The fraction of dead leaves ranged from 0.00 to 0.38. No dead leaves were observed in Te‐Qing, Swarna and MTU‐1010. The highest fraction of dead leaves was observed for Betichikon (0.38) followed by Duduruchi and D‐6766 (0.33). Our results suggest that this method in combination with other phenotyping methods could be used to quantify partial resistance to rice sheath blight.     

RELIABILITY OF THE FOCUS GROUP TECHNIQUE IN DETERMINING THE QUALITY CHARACTERISTICS OF MUNGBEAN [VIGNA RADIATA (L.) WILCZEC] NOODLES

Two commercial samples were evaluated in five focus group sessions to determine the reliability of the focus group technique in identifying the desirable and important sensory characteristics of dry and cooked mungbean noodles and to determine its quality characteristics. Each focus group consistently identified a similar list of desirable and undesirable characteristics. These results indicated that the focus group technique was a reliable method for determining consumer criteria for quality for mungbean noodles. When there is a need to determine consumers' definition of product quality at a stage when consumer testing is not desired, the focus group technique can be used as a valuable tool. Mungbean noodle quality was found to have two distinct aspects: appearance of the dry noodles and eating quality of the cooked noodles. Color, glossiness, and transparency are the most important characteristics of dry starch noodles while mouthfeel or texture is considered the most important characteristic of cooked starch noodles. Color, taste, and odor of the cooked noodles were considered not as important.     

特种稻谷蛋白亚基的研究

以陕西红香米、绿香米、紫糯、茉莉香米、黑帅、黑宝为实验材料,采用SDS-PAGE方法在pH为8.9,电流为15mA条件下,对其种子的谷蛋白进行了电泳分析,寻找其特征及其之间的差异。结果表明绿香米、黑帅都具有9条特征谱带;茉莉香米具有7条特征谱带;紫糯具有6条特征谱带;黑宝具有5条特征谱带;红香米具有4条特征谱带。分子量较高、蛋白谱带较多的品系为绿香米和黑帅(6～5条);分子量较高、蛋白谱带较少的品系为茉莉香米(2条)。     

A PCR-based marker for a locus conferring the aroma in Myanmar rice (Oryza sativa L.)

Aromatic rice is an important commodity for international trade, which has encouraged the interest of rice breeders to identify the genetic control of rice aroma. The recessive Os2AP gene, which is located on chromosome 8, has been reported to be associated with rice aroma. The 8-bp deletion in exon 7 is an aromatic allele that is present in most aromatic accessions, including the most popular aromatic rice varieties, Jasmine and Basmati. However, other mutations associated with aroma have been detected, but the other mutations are less frequent. In this study, we report an aromatic allele, a 3-bp insertion in exon 13 of Os2AP, as a major allele found in aromatic rice varieties from Myanmar. The insertion is in frame and causes an additional tyrosine (Y) in the amino acid sequence. However, the mutation does not affect the expression of the Os2AP gene. A functional marker for detecting this allele was developed and tested in an aroma-segregating F(2) population. The aroma phenotypes and genotypes showed perfect co-segregation of this population. The marker was also used for screening a collection of aromatic rice varieties collected from different geographical sites of Myanmar. Twice as many aromatic Myanmar rice varieties containing the 3-bp insertion allele were found as the varieties containing the 8-bp deletion allele, which suggested that the 3-bp insertion allele originated in regions of Myanmar.     

稻米外观品质性状遗传与分子定位研究进展

稻米外观品质主要是指稻米的粒形、垩白、透明度和籽粒色泽等,它不仅直接影响到人们的喜好,还与其他品质性状诸如蒸煮食用、加工等密切相关。因此,外观品质对稻米的商品价值有着十分重要的影响。本文从经典遗传与现代分子生物学两个方面对稻米主要外观品质的遗传研究进展进行了较全面的综述,包括粒长、粒宽、长宽比、粒厚、垩白、透明度和籽粒色泽等。综合近年来的遗传研究结果发现,大多数稻米外观品质性状都是由数量基因控制的。利用分子标记技术已将控制外观品质的QTL（qualitative trait locus）定位在不同的染色体上,为下一步的稻米外观品质改良提供了有利条件。     

THE ROLE OF THE KNOWLEDGE OF COLOR AND BRAND NAME ON THE CONSUMER'S HEDONIC RATINGS OF TOMATO PUREES

The objective of study was to assess the influence of the knowledge of color and brand name on consumer response to tomato purees. From focus group interviews it was found that taste and odor of fresh tomato were the most important drivers of consumer choice. To quantify that information a questionnaire was developed and it was submitted to fifty consumers of tomato puree. The questionnaires answers confirmed those coming from the focus group, although same discrepancies were found with those derived from the consumer test. Results showed that color and brand name seemed to be more important than taste and odor of fresh tomato, in fact those attributes, when consumers were tasting samples, affected not only hedonic judgments but sensory perception as well. Finally physico-chemical parameters derived from instrumental measurements have been compared to sensory data by means of PCA in order to validate the consumers'assessment of sensory attributes of tomato puree.     

CONSUMER ACCEPTANCE OF COMMERCIALLY AVAILABLE FRANKFURTERS1

Consumers want meat products that are healthful and affordable. However, consumers will repurchase a product only if it tastes good. Consumers identified reasons for purchasing frankfurters and evaluated overall acceptability of 10 commercially available frankfurters. Consumers listed “taste” as the most important factor when purchasing frankfurters; only 16% of the consumers indicated that nutrition/health was the most important criterion. Nineteen consumer-perceived sensory and liking attributes were measured for the frankfurters in this study. The intensities of the attributes ranged from low to moderately high. All the frankfurters scored in the low to moderate range for overall acceptability. Most of the scores for liking of individual attributes correlated highly with overall liking, indicating that many of the questions relating to attribute liking could be eliminated.     

Diversity of Global Rice Markets and the Science Required for Consumer-Targeted Rice Breeding

With the ever-increasing global demand for high quality rice in both local production regions and with Western consumers, we have a strong desire to understand better the importance of the different traits that make up the quality of the rice grain and obtain a full picture of rice quality demographics. Rice is by no means a ‘one size fits all’ crop. Regional preferences are not only striking, they drive the market and hence are of major economic importance in any rice breeding / improvement strategy. In this analysis, we have engaged local experts across the world to perform a full assessment of all the major rice quality trait characteristics and importantly, to determine how these are combined in the most preferred varieties for each of their regions. Physical as well as biochemical characteristics have been monitored and this has resulted in the identification of no less than 18 quality trait combinations. This complexity immediately reveals the extent of the specificity of consumer preference. Nevertheless, further assessment of these combinations at the variety level reveals that several groups still comprise varieties which consumers can readily identify as being different. This emphasises the shortcomings in the current tools we have available to assess rice quality and raises the issue of how we might correct for this in the future. Only with additional tools and research will we be able to define directed strategies for rice breeding which are able to combine important agronomic features with the demands of local consumers for specific quality attributes and hence, design new, improved crop varieties which will be awarded success in the global market.     

Are all GMOs the same? Consumer acceptance of cisgenic rice in India

India has more than 215 million food‐insecure people, many of whom are farmers. Genetically modified (GM) crops have the potential to alleviate this problem by increasing food supplies and strengthening farmer livelihoods. For this to occur, two factors are critical: (i) a change in the regulatory status of GM crops, and (ii) consumer acceptance of GM foods. There are generally two classifications of GM crops based on how they are bred: cisgenically bred, containing only DNA sequences from sexually compatible organisms; and transgenically bred, including DNA sequences from sexually incompatible organisms. Consumers may view cisgenic foods as more natural than those produced via transgenesis, thus influencing consumer acceptance. This premise was the catalyst for our study—would Indian consumers accept cisgenically bred rice and if so, how would they value cisgenics compared to conventionally bred rice, GM‐labelled rice and ‘no fungicide’ rice? In this willingness‐to‐pay study, respondents did not view cisgenic and GM rice differently. However, participants were willing‐to‐pay a premium for any aforementioned rice with a ‘no fungicide’ attribute, which cisgenics and GM could provide. Although not significantly different (P = 0.16), 76% and 73% of respondents stated a willingness‐to‐consume GM and cisgenic foods, respectively.     

COMPARISON OF ATTRIBUTE LIKING AND JAR SCALES TO EVALUATE THE ADEQUACY OF SENSORY ATTRIBUTES OF MILK DESSERTS

Just-about-right (JAR) scales and attribute liking questions are usually used to study consumer perception of the sensory characteristics of food products. The aim of the present work was to compare the performance of attribute liking and JAR scales to evaluate consumers' perceived adequacy of flavor and texture of milk puddings. Two groups of consumers were asked to evaluate eight milk desserts using (1) overall liking followed by attribute liking for texture and flavor and (2) overall liking followed by JAR scales for thickness, creaminess, sweetness and vanilla flavor. Overall liking scores were significantly different when JAR scales or attribute liking questions were considered. Texture, flavor and overall liking scores were highly correlated to each other, providing the same information. JAR scales correlated better with the intensity of sensory attributes evaluated by a trained sensory panel, being JAR percentages a reliable tool to study the adequacy of sensory attributes.

PRACTICAL APPLICATIONS

Results from the present work showed that consumers might not be able to independently evaluate their liking of different sensory attributes of a product. For this reason, the use of attribute liking questions for studying the adequacy of sensory attributes in complex products would not be recommended. JAR scales were better indicators of the adequacy of sensory attributes. Consumers were able to independently evaluate texture and flavor attributes using JAR scales. However, the influence of JAR scales on overall liking scores should be taken into account when including these scales on consumer studies.