Perceptual attributes of poultry and other meat products: a repertory grid application.

Increased demand for processed poultry products through the growth of home meal replacements and ready to eat products, present an opportunity for the development of new value-added poultry products. Repertory grid interviews were conducted to generate insight into consumer driven product development of these products. Procrustes analysis revealed that healthiness, nutrition, convenience, and processing attributes were most important parameters for discriminating amongst 24 meat and meat alternatives. "White meat", "healthier", "leaner", "good source of protein", "easy to cook" and "convenient", were found to positively influence consumer preferences for unprocessed chicken products, eggs and salmon while price did not appear to be important for differentiating the products. Traditional processed fish and poultry products, such as chicken nuggets, represented undesirable composition, processing and quality concerns. Identification of consumer attributes for discriminating poultry products among other meat alternatives can guide the development of competitive value-added poultry products.

An international study on the importance of androstenone and skatole for boar taint: III. Consumer survey in seven European countries.

There has long been debate over the relative importance for consumer acceptability of androstenone and skatole. The objective of this study was to investigate consumer reaction to pig meat of varying levels of androstenone and skatole in seven member states of the European Union. Over 4000 entire male pigs (and 233 gilts as a control) were produced in six European countries, and a sub-sample of 420 were selected to represent a range of androstenone and skatole levels. Loin samples from these pigs were distributed to the seven participating countries. Samples were prepared and cooked according to standardised procedures in each of the countries and presented to pork consumers. Each consumer rated samples from five pigs for liking of flavour and liking of odour. Although there were significant differences between country panels in their liking of meat from entire males generally, there was a greater degree of dislike as both androstenone and skatole increased. This reaction was stronger for skatole than androstenone and consumers reacted more negatively in terms of odour than flavour.

An international study on the importance of androstenone and skatole for boar taint: IV. Simulation studies on consumer dissatisfaction with entire male pork and the effect of sorting carcasses on the slaughter line, main conclusions and recommendations.

An international study has been conducted in order to determine the respective contributions of androstenone and skatole to boar taint and their possible variations according to production systems and consumer populations. The presentation of the study and the main results concerning skatole and androstenone levels and data from sensory evaluation or consumer surveys are reported in companion papers. The present paper summarises the main conclusions of the study and gives tentative recommendations. A simulation study was conducted, based on the skatole and androstenone levels currently observed in European populations of entire male pigs and on the results of the consumer surveys. The first part of the simulation study demonstrated that, overall, 6.5% (odour) and 3.0% (flavour) more consumers were dissatisfied with entire male than with gilt pork. The differences were, however, very variable according to countries. Consumer dissatisfaction for the odour of entire male pork was mostly associated with high skatole levels, while androstenone had little influence on it. On the other hand, androstenone and skatole had similar contributions to the level of dissatisfaction for flavour. From the present study it is not possible to determine clear cut-off levels for androstenone/skatole. The regression equations presented in [Matthews, K. R., Homer, D. B., Punter, P., Béague, M. P., Gispert, M., Siret, F., Leask, H., Fonti i Furnols, M., & Bonneau, M. (2000). An international study on the importance of androstenone, skatole for boar taint: III. Consumer survey in seven European countries. Meat Science, 54, 271-283] provide a basis for decision making. However, due to methodological limitations, the results may underestimate consumer reaction to entire male pork. The second part of the simulation study demonstrated that sorting carcasses on the basis of androstenone/skatole would reduce, but not eliminate, differences in consumer dissatisfaction between entire male and gilt pork. For odour, taking androstenone into account did not improve the efficiency obtained from sorting using skatole only. For flavour, sorting using both compounds was more efficient than sorting using skatole only. Sorting out 15% of the entire males, on the basis of skatole only, would result in a difference in the proportion of dissatisfied consumers of 4.2% (odour) or 2.0% (flavour) between entire male and gilt pork. The results of the last part of the simulation study demonstrated that decreasing skatole in entire male pig populations, to levels as low as 0.10 ppm, would still result in a difference in the proportion of dissatisfied consumers of 3.2% (odour) or 1.6% (flavour). To reduce this difference further, the levels of both compounds would have to be reduced still further. The lowest difference that can be achieved is 2.3% (odour) or 0.4% (flavour). The conclusions of the present study may differ according to whether immediate commercial applications or long-term goals are considered. On the basis of the skatole and androstenone levels currently observed in entire male pig populations, sorting out procedures based on skatole is the easiest way to rapidly achieve a significant decrease in consumer dissatisfaction with entire male pork. In most countries, however, this will not be sufficient to obtain the same level of acceptability as with gilts. In the long term, a sharp reduction in both skatole and androstenone would have to be achieved in entire male pig populations to obtain low differences in acceptability between entire male and gilt pork.

Sensory evidence for olfactory receptors with opposite chiral selectivity.

Human odor responses to alpha-ionone enantiomers were measured by psycho-physical methods. Surprisingly, subjects' relative sensitivities for these enantiomers were found to diverge widely, some subjects being much more sensitive to (+) than to (-) and vice versa. In 63 subjects the (+)/(-) threshold concentration ratio varied over 4 orders of magnitude. Nine subjects with extreme (+)/(-) ratios were further tested several times over a 7-month period and retained stable ratios. These same nine subjects, when tested for threshold sensitivity to carvone enantiomers, showed (+)/(-) ratios that varied only in a narrow range and did not correlate with their ionone ratios. It is suggested that odor discrimination of alpha-ionone enantiomers involves at least two receptor types of opposite chiral selectivity and that their distribution varies independently in the human population.

Determination of odour affinities based on the dose-response relationships of the frog's electro-olfactogram.

Electro-olfactograms (EOG's) recorded from the frog's olfactory epithelium for 11 substances were used to calculate dissociation constants which in turn serve as an index for the affinity between odorant and receptor site. These constants were calculated with and without a correction for the odour partition between water and air. For a homologous series of 7 n-alcohols these values decrease up to 1-heptanol. The dose-response relationships were based on the peaks of the EOG's since the peak/plateau-ratio was concentration-dependent for some of the substances.