Overview and Basic Principles. Physiological and Psychological Foundations of Sensory Function. Principles of Good Practise. Discrimination Testing. Discrimination Theories and Advanced Topics. Threshold Testing as a Special Case of Discrimination Tests. Scaling Models and Numerical Measurement. Time Intensity Methods. Context Effects and Biases. Descriptive Analysis. Texture. Color and Appearance Measurement. Acceptance and Preference Testing - Laboratory Applications. Acceptance and Preference Testing - Consumer Tests Outside the Laboratory. Qualitative Research Methods. Data Relationships & Multivariate Applications. Strategic Research. Overview and Recap. Statistical Appendices.

Sensory Evaluation of Food: Principles and Practices

Given the significant increase in consumer interest in organic food products, there is a need to determine to what extent there is a scientific basis for claims made for organic produce. Studies comparing foods derived from organic and conventional growing systems were assessed for three key areas: nutritional value, sensory quality, and food safety. It is evident from this assessment that there are few well-controlled studies that are capable of making a valid comparison. With the possible exception of nitrate content, there is no strong evidence that organic and conventional foods differ in concentrations of various nutrients. Considerations of the impact of organic growing systems on nutrient bioavailability and nonnutrient components have received little attention and are important directions for future research. While there are reports indicating that organic and conventional fruits and vegetables may differ on a variety of sensory qualities, the findings are inconsistent. In future studies, the possibility that typical organic distribution or harvesting systems may deliver products differing in freshness or maturity should be evaluated. There is no evidence that organic foods may be more susceptible to microbiological contamination than conventional foods. While it is likely that organically grown foods are lower in pesticide residues, there has been very little documentation of residue levels.

A comparison of the nutritional value, sensory qualities, and food safety of organically and conventionally produced foods

http://smas.chemeng.ntua.gr/miram/files/publ_148_10_2_2005.pdf

Consumer perception of meat quality and implications for product development in the meat sector—a review

Consumer perception of meat quality and implications for product development in the meat sector.

Consumer preference, behavior and perception about meat and meat products: an overview.

Expectations are generated by a variety of factors. We indicate a flow chart for the role of expectations at the point of choice and in influencing sensory perception at the time of consumption. We review the sparse literature on how advertising, packaging and information generate sensory expectations. The application of various theories to explain the observed effects of sensory expectations are reviewed. There is overwhelming evidence for assimilation-contrast effect, although no studies have been specifically designed to detect it. Finally we review the reasons why individuals might differ in the way that expectations influence sensory perception. These reasons include ideas from persuasion literature and private body consciousness. A number of behavioral hypothesis that follow from these theories are developed.

The generation of sensory expectation by external cues and its effect on sensory perception and hedonic ratings: a review

Consumers unfamiliar with passion-fruit juice were presented with 24 computer generated package images on which six packaging factors (background color, picture, information, brand, language and shape) had been manipulated and asked to give scores for six expected sensory attributes (sweetness, pureness, sharpness, refreshing, freshness, naturalness) and liking. Significant effects were obtained for each attribute, with background color and information being the most important. Consumers varying in Need For Cognition (NFC) were affected differently by the investigated features of the package. High NFC individuals used less of the packaging factors than low NFC subjects did.

Use of computer‐generated images and conjoint analysis to investigate sensory expectations

Free-choice profiling (FCP) was carried out in order to investigate how naive consumers (who had never tried the product before) described and perceived passion-fruit juice. This method allows participants to use their own attributes to describe and quantify food products and beverages. The study used four different samples of passion-fruit juice, analyzed by 10 consumers in three replicates. The data were analyzed by using generalized Procrustes analysis. The first and second dimension accounted for 78.7% of the variance. The product consensus configuration revealed that assessors were able to reproduce samples’ description, and also to differentiate samples. Free-choice profiling is a useful method for describing consumer perception of passionfruit juice.

The consumer sensory perception of passion-fruit juice using free-choice profiling

The packaging and labelling of a food or beverage play an important role in its selection because it is the major source of information for consumers, permitting them to make better choices in the marketplace (McCullough and Best 1980; van Trijp and Steenkamp 1998). Three aspects are important and maybe distinguished in labelling: its potential as a marketing tool, its relevance from an industry viewpoint, and its potential benefits to the consumer (Verbeke and Viaene 1999). Previous studies have demonstrated that the design and content of a food label and its associated packaging may affect the perceived quality, intention to purchase, and liking (Tom et al. 1987; Thogersen 1994; van Dam and van Trijp 1994).

Product Packaging and Branding

We investigate the reliability and predictive power (correspondence with home-use test [HUT] outcomes) of central location tests (CLTs) using a tea bag product. The setting involves three different CLT testing contexts reflecting “natural versus controlled” approaches: (1) traditional CLT, using controlled testing with ad libitum consumption (n = 47); (2) dosing CLT (DCLT), offering dose choices (sugar and milk combinations) that are different across consumers but similar across samples for individuals (n = 47); and (3) free choice CLT (FCLT), simulating natural tea-making circumstances and individual brewing preferences (n = 44). CLT results are compared with outcomes from HUTs, employing Pearson correlation coefficients on CLT-HUT scores as indicators of the ability of CLT outcomes to predict HUT outcomes. Analysis of variance and internal preference mapping methods are also applied. FCLT is found to better discriminate between samples than the other CLTs. However, only the DCLT group revealed a statistically significant (though weak in magnitude) relationship (r = 0.234) between CLT and HUT.



PRACTICAL APPLICATIONS

Central location tests (CLTs) are used extensively in sensory research because of their cost-effectiveness and ease of implementation. However, questions remain about whether CLT responses are consistent with responses from more natural, longer term testing environments. This research studies consumer liking in CLT and compares it with choices of tea made and consumed at home in home-use tests (HUT). It aims to address two major outcomes from three different CLT testing contexts: (1) the degree of relationship to liking scores derived from long-term testing in HUT; and (2) ability to distinguish between samples. The testing product chosen here involves complexity in preparation and significant cultural contextual consumption. Thus, the results are expected to contribute to improving design of CLTs to predict long-term acceptance and choices in food research.

Hal Macfie

Papers

The generation of sensory expectation by external cues and its effect on sensory perception and hedonic ratings: a review

Use of computer‐generated images and conjoint analysis to investigate sensory expectations

The consumer sensory perception of passion-fruit juice using free-choice profiling

Product Packaging and Branding

The influence of testing context on tea bag product acceptance in central location tests