Microbial transglutaminase forms nondisulfide covalent crosslinks in proteins and is being used in foods. This enzyme may produce beneficial effects during breadmaking that are comparable to traditional oxidizing improvers, hypothesized to act via formation of disulfide crosslinks. Transglutaminase greatly improved the crumb strength of baked loaves and provides a potential solution to a common consumer complaint. Transglutaminase also reduced the required work input and substantially improved the water absorption of the dough. Each of these effects would lower processing costs for commercial baking

Microbial transglutaminase forms nondisulfide covalent crosslinks in proteins and is increasingly being used in foods. We have previously demonstrated beneficial effects of microbial transglutaminase during breadmaking, which are comparable to traditional oxidizing improvers, hypothesized to act via formation of disulfide crosslinks. Transglutaminase substantially improved the lift of puff pastry. It also had a dramatic effect on the volume of yeasted croissants made with both white flour and a blend of wholemeal and white flour. Furthermore, these effects were preserved after the pastry and croissant doughs had undergone frozen storage for periods of up to 90 d. Transglutaminase, therefore, offers a potential solution to the problem of pastry and croissant dough deterioration on frozen storage.

Saliva addition plays an important role in bolus formation. During chewing, food breaks down, exposing food particles to saliva. The aim of this study was to explore and understand how bolus moisture content changes during the oral processing of solid foods. Twelve subjects chewed commercially produced solid foods; the boluses were collected at different stages of the mastication process, including the swallowing point, and all of the boluses produced were analyzed for their moisture content. The chewing sessions were recorded on video, enabling the number of chews to be assessed for each subject and food type. Results showed that moisture content of boluses during mastication increased linearly at a rate depending on the subject and food types studied. It was found that for the food types studied, an increase in initial food moisture content increased the bolus moisture content at the swallowing point. Practical Applications Sensory perception experienced during oral processing of foods is through sensing the bolus properties, which change continuously in between ingestion and swallowing. Understanding changes in bolus moisture content, the role of food structure and effects on sensory perception can help in designing foods with predictable sensory attributes. This study demonstrated that while saliva additions vary between people and food types, they increase linearly during mastication. Changes in bolus moisture content during mastication could be used to guide the design of solid foods with target properties.

A series of biscuit‐like model foods that vary primarily in hardness, while keeping other sensory attributes less variable, was developed and used to investigate the relationship between fundamental fracture properties and the sensory perception of hardness of brittle solid foods. Fifteen biscuit samples were evaluated by both a trained sensory panel and three instrumental tests (three‐point bending test, single‐edge notched bend test and modified texture profile analysis), and their relationships were determined by simple linear regression analysis. Correlations revealed that the perceived hardness during biting or chewing is fracture related, and it is directly related to the amount of stress required to initiate and propagate a crack in a material (i.e., fracture stress [σ] and critical stress intensity factor [KIC], respectively). The fracturing of these hard and brittle biscuits appeared to be associated with the release of energy as sound, and thus, the perceived hardness and crunchiness were indistinguishable. PRACTICAL APPLICATIONS Sensory evaluation is time consuming and expensive, and, therefore, reliable and practical (faster, less expensive and reproducible) instrumental methods are needed to accurately predict sensory texture attributes, at least, in the product development and quality control stages. This study demonstrated that the perceived hardness of biscuits can be tracked by σ and KIC with remarkable precision. These properties may be used as a reliable replacement for a sensory assessment of hardness in brittle solid foods, where applicable.

Twenty cereal snack bar samples (10 recipes ¥ 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 Ն 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 APPLICATIONSTexture is one of the most important sensory characteristics that determine consumer preference for cereal snack bars and is usually assessed by 1 Corresponding