Results and DiscussionDuring storage of bread for 168 h, ∆H AP increased while the relative amount of FW decreased (Table 1). Water becomes unfreezable due to inclusion into the amylopectin crystals but also due to inclusion into the continuous, rigid amylopectin network. No amylopectin retrogradation was observed during drying. Crumb firmness increased during storage and drying ( Figure 1).The decreased crumb moisture content during storage did not result in an increased crumb firmness (Figure 1), showing that amylopectin retrogradation was largely responsible for crumb firming during storage. However, the increase in melting enthalpy levelled off after a couple of days of storage (Table 1), while crumb firmness increased further. This points to an additional phenomenon which contributes to crumb firmness.With 1 H NMR, changes in the distribution of protons from water and biopolymers can be observed. During storage of bread, the area of population A (rigid protons) increased due to formation of amylopectin crystals (Figure 2a). In addition, the mobility (T 2 relaxation time) and area of population E (mobile exchanging protons in the formed gel network) decreased during bread storage due to formation of a continuous, rigid amylopectin network and crumb to crust moisture migration (Figure 2a). Bread crumb firming is a complex process. It is generally accepted that amylopectin retrogradation is an important contributor to crumb firming during storage, but there is no direct cause and effect relationship between both processes 1 . Besides formation of amylopectin crystals 1 , water diffusion also affects crumb firmness during storage. Literature is scarce about the impact of such diffusion. It occurs on a macroscopic scale, i.e. from crumb to crust 2 , as well as on a molecular scale, i.e. from gluten to starch 3 . However, the relative importance of water redistribution and amylopectin retrogradation for bread firming is still under debate. Since water related phenomena are involved in crumb firming, the use of low resolution (LR) proton Nuclear Magnetic Resonance ( 1 H NMR) to examine bread crumb holds promise. the objective of this study was to investigate changes during bread storage, thereby distinguishing between the effect of crumb to crust migration and evaporation of water and the effect of amylopectin recrystallization with water incorporation into the resulting starch network. Introduction and Objective ReferencesBread making process Bread was made using a straight-dough method [100.0 g wheat flour (14.0% moisture), 5.3 g compressed yeast, 6.0 g sucrose, 1.5 g NaCl, 57.0 mL water] as described in Bosmans et al. (2012) 4 . Differential scanning calorimetry (DSC) measurementsThe melting enthalpy of retrograded amylopectin (∆H AP ) and the relative amount of freezable water (FW) were determined with DSC 5 . Firmness measurementsCrumb firmness was detected with an Instron 3342 (Instron, Norwood, MA, USA) on fresh, stored (for 168 h) and dried bread crumb 5 . H NMR measurementsProton relaxation measurement...

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Foam‐type cakes are complex food systems. Their main ingredients are wheat flour, hen eggs, sugar, leavening agent, and, in some cases, oil and/or surfactants. In contrast to the vast amount of research outcomes on the contribution of ingredients to the quality of batter‐type cake systems, information on the functionality and importance of the ingredients and their constituents in foam‐type cake systems is lacking. This review defines foam‐type cakes, describes how they are made, summarizes the current knowledge of factors determining their quality, and identifies the current knowledge gaps.

The use of starch in food systems in many instances relies on its thickening and gelling capacity. When native starches fail to match process and/or product‐specific requirements, starches are physically and/or chemically modified to meet end‐use demands. Evidently, differences between starches of varying botanical origin have to be considered when selecting or modifying starches for particular applications. Potato starch (PS) ranks third in world production after maize and wheat starches. Its unique properties differ from those of cereal and pulse starches and are directly related to its molecular structure and organization. This review summarizes the differences between PS and cereal and pulse starches and how they set it apart in terms of gelatinization, pasting, gelation, and retrogradation. Recent advances in improving PS pasting and gelation using enzyme technology and mineral ions are also described.

Pastry products are produced from heterogeneous multilayered dough systems. The main ingredients are flour, water, fat and sugar for puff pastry, and the same plus yeast for fermented pastry. Key aspects in pastry production are (i) building laminated dough containing alternating layers of dough and bakery fat and (ii) maintaining this multilayered structure during processing to allow for steam entrapment for proper dough lift during baking. Although most authors agree on the importance of gluten and fat for maintaining the integrity of the different layers, detailed studies on their specific function are lacking. The exact mechanism of steam entrapment during dough lift and the relative contribution of water set free from the fat phase during baking also remain unclear. This review brings together current knowledge on pastry products and the factors determining (intermediate) product quality. Its focus is on flour constituents, fat, water, and (where applicable) yeast during the different production stages of pastry products. Future research needs are addressed as the knowledge on biochemical and physical changes occurring in flour constituents and other ingredients during pastry production and their effect on product quality is currently inadequate.

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