Bread staling

Sodium propionate is also often used as an antifungal agent. Calcium is often preferable to sodium, both to reduce sodium levels in the diet and because calcium ions are necessary for the enzyme a-amylase to act on the starches in bread, making them available for the yeast, and improving the texture of the bread. Stale bread is caused by the starch amylose recrystallizing. The enzyme a-amylase converts some of this starch to sugars, which helps prevent recrystallization. 

Another laboratory invoked the role of water in bread staling involving a zipper mechanism that results in the formation of interchain crosslinks 492 Moisture redistribution from crumb to crust played a significant role in crumb firming and amylopectin recrystallization for breads stored for more than seven days 493 According to Piazza and Masi494 to inhibit staling it is more important to slow the dehydration phenomena than it is to increase the initial moisture content in the bread. 

Chinachoti P, Vodovotz Y. Bread Staling. Boca Raton, FL CRC Press 2000. 

Moreover, the bread crumb s moisture loss during seven days of storage open to the air, also did not show a consistent dramatic effect on these two tensile parameters (Chen et al. 1994) as one would expect. The same can be said about the compression parameters, which too showed little correlation with the moisture loss, which was measurable, of course. These reported findings, if indeed representative of the three tested breads (white, Canadian and whole wheat), would suggest that the initial textural changes that accompany bread staling are quite subtle and hence cannot be always manifested in the described crude mechanical parameters. An alternative explanation is that the failure to find the expected trends was mainly due to the large scatter in the experimental results that masked the true trend, if it really existed. 

The n-alkyl portion of emulsifiers such as glycerol monostearate form a complex with helical regions of starch, a phenomenon that is thought to be responsible for the ability of GMS to retard starch crystallization in bread crumb, slowing the process of staling. Several workers have measured the stoichiometry of complex formation by using various methods. Some of these studies are mentioned later in connection with the discussion on bread staling here three typical reports are summarized. 

Microbiological nutrient gelforming agent emulsifier bread staling retardant meat texturizer meat substitute... 

Economics. No consideration of the literature would be complete without the economic study made by the Food Research Institute of Stanford University (66). The studies are mainly concerned with crops, markets, and economics, and comprise a monumental contribution to the literature of wheat. Some technical papers on wheat in the diet, wheat protein, starch and flour quality, bread staling, utilization of wheat germ, and physical tests of flour quality are included. An index to this series (62) consists of abstracts of the annual reviews and special studies, and a chronological list of the individual issues, and lists, by author and subject, of the special studies. 

Gray, J.A. and Bemiller, J.N. 2003. Bread staling Molecular basis and control. Comp. Rev. Food Sci. FoodSaf. 2, 1-21. 

Masi, P., Cavella, S., and Piazza, L. 2001. An interpretation of the rheological behavior of wheat flour dough based on fundamental tests. In Bread Staling (P. Chinacoti and Y. Vodorotz, eds), pp. 75-91. CRC Press, Florida. 

Results in this study are applicable for constant water levels. In baking processes, evaporation and condensation events occur in addition to changes in starch and gluten and therefore must be considered.16 This work could be extended to monitor changes in the distribution of water between starch and gluten during bread staling. 

Bread staling can shorten the shelf-life of bread and generate economic loss. This encourages more researchers to develop new techniques to control or retard the staling process. These techniques include, but are not limited to, the addition of glucose oxidase, xylanase, whey protein, soy protein, pentosans, arabinoxylans, hydroxypropylmethylcellulose and emulsifiers [19,26]. Small molecule materials, such as ribose, xylose, maltose and fructose, are also considered as antistaling agents due to their ability for the transformation of bread crystalline patterns [27]. 

Tian,YQ,YLi,ZYJin,XMXu,JPWang,AQJiao,BYuandTTalba(2009)./6-Cyclodextrin (/3-CD) A new approach in bread staling. Thermochima Acta, 489,22-26. 

Once a product has been made, the ability to maintain its stability comes into question. Thus, Chapter 8 covers the topic of shelf life and focuses on the well-known phenomenon of bread-staling and the factors causing it. Starch is the cereal component believed to play the principal role in the staling of aerated products. 

Is there any way to eliminate crumb-firming in bread-staling ... 

Axford, D. W. E., K. Colwell, and G. A. H. Elton. 1966. Bread staling The current state of knowledge, 1-19. Chorleywood, England British Baking Industries Research Association. 

Chinachoti, R, and Y. Vodovotz. 2000. Bread staling. Boca Raton, FL CRC Press. Glasstone, S., K. J. Laidler, and H. E5n-ing. 1941. The theory of rate processes. New York McGraw-Hill. 

LR NMR can monitor the distribution and mobility of water during bread making (dough, baking to bread, staling). 

Increases in amylopectin crystallinity underlies part of the phenomenon known as bread staling (10). However, it has been recently shown that a rise in the glass transition temperature of the gluten, probably due to moisture migration, is more important (14-16). 

P. Chinachoti and Y. Vodovitz, eds.. Bread Staling, CRC Press, Boca Raton, 2001. 

Around 70°C, the gelatinization of finely divided flours (starches) mixed with water can be observed. Retrogradation, for instance bread staling, can also be studied [97]. Crystallization of amorphous sugars (e.g., crystallization of amorphous lactose in milk powders [98]) can be detected in reconstituted foods. However, protein denaturation is no longer detected elearly when studying liquid whole milk products containing lipids, lactose, caleium, etc. 

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