Cereal chemists are interested in rheology because the dough undergoes some type of deformation in every phase of the conversion of flour into baked products. During mixing, dough is subjected to extreme deformations, many that exceed the rupture limit; during fermentation, the deformations are much smaller and therefore exhibit a different set of rheological properties; during sheeting and molding, deformations are at an intermediate level; and, finally, during proofing and baking, the dough is subjected to a range of deformations at varying temperatures. Accordingly, the application of rheological concepts to explain the behavior of dough seems a natural requirement of research on the interrelationships among flour constituents, added ingredients, process parameters, and the required characteristics of the final baked product. At any moment in the baking process, the rheological behavior, that is, the nature of the deformation, exhibited by a specific dough derives from the applied stress and how long the stress is maintained. The resulting deformation may be simple, such as pure viscous flow or elastic deformation, and therefore easy to define precisely. Moreover, under some conditions of stress and time (i. e. , shear rate), doughs behave as ideal materials and their behavior follows theory derived from fundamental concepts. Under usual conditions encountered in baking, however, the rheological behavior is far from ideal; shear rates vary widely and sample size and dimensions are ill-defined.

Soybean and pulse flours are excellent source of various macro- and micro-nutrients, such as proteins, dietary fibers, minerals, and bioactive compounds associated with health benefits. They are becoming increasingly important to the food industry as product formulators and consumers are seeking nutritionally attractive ingredients. Fortification of cereal foods with pulse or soybean flour represents a promising approach to enhance their nutritional value, health benefits, and flavor profiles. However, the lack of gluten protein in these flours results in undesirable dough rheological properties and baked products with poor texture and other quality defects. This thesis is comprised of two studies that aimed to investigate and understand the effect of incorporating soybean or pulse flours on the dough properties and bakery product quality. In the first study, we investigated the effect of formulation (e.g., shortening, sugar, and water) and pretreatment of soy flour on dough properties and cookie texture in a gluten-free (GF) system. Cookies were formulated with composite flours containing commercial GF flour and original or pretreated soy flour (70/30). Reducing agents (cysteine, glutathione, and sodium sulfite) and protease (Flavourzyme) were used for soy flour pretreatment, respectively. The modified proteins were characterized by analyzing contents of free sulfhydryl and free amino group and SDS-PAGE profiles. Dough properties were measured using mixograph and texture analyzer. Cookie quality was determined by analyzing spread ratio, texture, color, and moisture content. Results showed that adding relatively higher amount of sugar, shortening, and water greatly increased cookie spread and improved cookie cracking pattern, though it also increased the stickiness of the dough. Pretreatment of soy flour with reducing agent or protease reduced protein molecular size, and thus, weakened the GF dough, which also led to increased cookie spread and better cracking pattern. In the second study, we investigated the effect of different types (yellow pea, green pea, red lentil, and chickpea) and amounts (0-25%) of whole pulse flours on whole wheat flour-based dough properties and bread quality. Pulse grains were ground using a Wiley mill to obtain whole pulse flour. Mixolab was used to analyze mixing and pasting properties of the whole wheat/pulse composite flours, and bread was characterized. Results showed that increasing the amount of pulse flour in the composite significantly weakened the dough and decreased dough viscosity due to a dilution of gluten proteins. Bread specific volume decreased, and hardness increased with higher amount of pulse flours. Among all the tested pulse flours, the composite flour containing yellow pea flour had overall better baking performances. This research demonstrated the potential of utilizing soybean and pulse flours for bakery applications. The knowledge will be useful for the industry in developing new gluten-free or fortified bakery products.

This practical guide illuminates all aspects of breadmaking. It provides a thorough understanding of the many new developments shaping the industry and offers detailed technical coverage of the complex processes that make bread and fermented products. It examines the nature of bread products, the role of the ingredients in determining their quality, processing methods and their control, and equipment functions. In addition, the book explores the contributions of individual components and processing stages to final bread quality. It also reviews the current state of technical knowledge on breadmaking.

ABSTRACT: Twenty-six papers presented at a symposium for theInternational Union of Food Science and Technology, are included. Two categories of papers are offered: 1) critical reviews of present knowledge on specificied themes, and 2) unpublished data and theory. The papers' approaches are multidisciplinary. Topics included the 1) psychophysics of the sensory evaluation of textural properties; 2) instrumental evaluation of textural properties and common problems associated with measurement; 3) food processing aspects of food rheology; 4) rheological properties of vegetables proteins and their relevance to the preparation of meat extenders and substitutes; 5) the rheology and microstructure of baker's dough and baked products; and 6) the relationship between structure and rheological properties of commodities.