Baking of bread

Propionibacteria, together with lactic acid bacteria and yeasts, are added to some leavens for dough in order to enrich bread in propionic acid, in addition to lactic and acetic acids produced in the process of fermentation. Such bread contains up to 0.28% of propionic acid and has a prolonged storage life due to the suppressive action of propionic acid on mold growth. This effect can only be achieved if the number of propionibacteria is at least 2.5 10 cells per g raw dough (Spicher, 1983). 

As a leaven for bread a mixed culture of Lactobacillus brevis TKK 105-6-1 and P. acidipropionici TKK 114-3-1 was used after three days of combined cultivation at 30 C in the medium containing hydrolyzed wheat flour, yeast extract and mineral salts (Javanainen et al., 1987) the pH of the culture was adjusted to 5.0-5.8 by adding calcium carbonate (20 g/1). Almost 

By adding propionic acid bacteria to leavens bread can be enriched in vitamin B this is especially important for vegetarians and persons suffering from various diseases arising from vitamin B deficiency (see above). Vitamin Bn content in bacterial cells is regulated by the availability of cobaltous salts in the medium (see Chapter 5). Hence, tiie vitamin Bn content of bread can be modified by using an appropriate leaven. 

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There are several operations in making baked products and there are the machines that are used to carry them out. While there has been a revolution in the baking of bread, the fundamental processes of baking products have not changed some of them are merely carried out in a different way. There are bakeries all over the world, including the third world, and these bakeries do things in different ways. 

To make a solid foam we start from a liquid foam and induce solidification. This can be achieved by a chemical polymerization (Styrofoam), by lowering the temperature (pumice stone or a souffle), or by increasing the temperature to induce a structural transition (baking of bread). Porous solids can appear as solid foams because of their low density and their high content of gas. The difference between the two is that in a porous solid we have a bicontinuous structure while the individual cavities in a foam are closed. This is an important difference because porous solids tend to adsorb liquids due to capillary effects and then completely change their properties. 

Maillard reactions can be involved in the manufacture of foods in at least three quite different ways. First, there is the unconscious role played in the development of flavor in such traditional processes as the roasting of coffee and cacao beans, the baking of breads and cakes, and the cooking of meats. Second, there is the deliberate use of Maillard technology in the production of artificial (or engineered) foods and flavors. Third, there are the efforts to inhibit undesirable results of Maillard reactions in food processing today. 

Food canning results in losses of vitamin B6 of 20 to 30 percent. Milling of wheat may result in losses of up to 80 to 90 percent. Baking of bread may result in losses of up to 17 percent. 

The utmost care should be used when one undertakes the PREPARATION AND BAKING OF BREAD AT HOME... 

High-speed hammer or pin mills result in some selective grinding. Such mills combined with air classification can produce fractions with controlled protein content. Flour with different protein content is needed for the baking of breads and cakes these types of flour were formerly available only by selection of the type of wheat, which is limited by growing conditions prevaihng in particular locations [Wichser, Milling, 3(5), 123-125 (1958)]. 

Although the chemical behavior of a gas depends on its composition, all gases have remarkably similar physical behavior, which is the focus of this chapter. For instance, although the particular gases differ, the same physical behaviors are at work in the operation of a car and in the baking of bread, in the thrust of a rocket engine and in the explosion of a kernel of popcorn, in the process of breathing and in the creation of thunder. 

Although the availability of bread is documented in some of the earliest human writings, pictorial descriptions of the process only date back to the Egyptians (Fig. 6.4-1) and the Romans (Fig. 6.4-2) [6.4.1]. Fig. 6.4-1 describes the mixing, forming and baking of bread and includes special, most probably devotional shapes (top center). It is reproduced from a painting in a tomb from the time of Pharaoh Rameses III (about 1175 BC) [6.4.1, 6.4.2]. 

Moore et al. (1957) observed by the paper chromatograph method that approximately 47% of the tocopherols in ordinary unbleached flour were destroyed in the baking of bread, yet sufficient remained to prevent in vitro hemolysis by dialuric acid method of Gyfirgy and Rose (1949). The trace amounts of tocopherols in bleached flour were destroyed in bread baking. 

The main processes that rely on microbial action for their success are the brewing of beer, the fermentation of wine, and the baking of bread and other leavened baked goods. The brewing of beer and the fermentation of wine are, in principle, the same process the differences between them consist primarily of the materials used to provide flavors and the order in which the resulting solutions are handled. At the heart of both is the same simple yeast-mediated fermentation of sugar and water to produce carbon dioxide and ethanol. 

Biotin losses during the baking of bread and other cereal products are small. Cooking legumes results in loss ofvitamin, which reaches 5-15%, depending on the time of soaking. 

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