[A transcultural study on stirred strawberry yogurt: consumer acceptability versus sensory quality with trained...

The present work was designed in order to obtain the cut off point, to be used in a shelf life study on whole stirred strawberry yogurt. The study was simultaneously carried out in Argentina, Chile and Costa Rica, assaying the same kind of product, elaborated in each one of the countries. The sensory quality parameters obtained from trained panelists and the consumers acceptability, were correlated by using the cut off point methodology through a quality evaluation by the Karlsruhe scale. According to preliminary studies, the storage at 42 degrees C produced considerable damage on parameters such as pH, acidity (volumetric assay), viscosity and sensory quality. For each sample, the cut off point was determined. This value corresponds to the threshold score for the sensory quality, where the consumer starts to perceive negative changes in the product, when comparing with the fresh product. The rejection percentage was also calculated according to the cut off point. The cut off points and the percentage of rejection obtained by the three participating countries were similar. Data obtained from Costa Rica showed changes in color, acidity and rancidity. Argentinean yogurts developed acidity that had a negative effect on texture, appearance and residual flavors. Chilean samples presented a sensory quality that remains almost without change through the studied time. The differences of the deterioration pattern amongst the three countries, demonstrates that the products are different in formulation and elaboration process, in spite of been the same kind of yogurt. This could be explained by differences specified in the regulation of each country.