PREDICTING THE SENSORY TEXTURE OF CEREAL SNACK BARS USING INSTRUMENTAL MEASUREMENTS

Twenty cereal snack bar samples (10 recipes x 2 oven sides) with a wide range of textural attribute intensities were evaluated by both a trained sensory panel and instrumental methods to determine which instrumental methods accurately predict sensory textural attributes of cereal snack bars in product development and quality control. Very few studies have been devoted to assessing the textural properties of cereal snack bars. We undertook a range of instrumental tests (three-point bending test, cut (shear) test, puncture test, texture profile analysis [TPA] and modified TPA using a probe size smaller than the sample size) using an Instron Universal Testing Machine. Moisture content and water activity of the bars were also measured. Relationships between sensory textural attributes, and instrumental and physical measurements of the bars, were determined by simple regression analysis. Several of the instrumental measurements showed a high degree of correlation (r >= 0.85, P < 0.001) with some of the sensory textural attributes. Correlations revealed that some of the instrumental measurements could be used to predict the sensory attributes of firmness, chewiness and crumbliness. The compression energy required for the second compression cycle of the modified TPA gave the best prediction of these attributes. Relationships between other sensory textural attributes (sample recovery, return time for springiness, moistness, mouthfeel, adhesiveness to teeth) and instrumental and physical measurements of the bars were less clear. PRACTICAL APPLICATIONS Texture is one of the most important sensory characteristics that determine consumer preference for cereal snack bars and is usually assessed by sensory evaluation. However, sensory evaluation is time-consuming and expensive, and therefore, reliable and practical instrumental methods are needed to accurately predict sensory texture attributes. This article demonstrates that some of the sensory texture attributes of cereal snack bars can be well predicted using instrumental methods, and suggests possible instrumental methods that can be used at least in the product development and quality control stages. This study also contributes to enhance the knowledge in the research area of sensory instrumental correlation.