Type of Lactobacillus plantarum belongs to homofermentative types of subgroups streptobaktery. The

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This is natural, because an excessive increase ddt in the acidity of sourdough fermentation activity reduces yeast and inhibits ddt the growth of lactic acid bacteria, has a negative effect on the activity of enzymes, enzymes and flour on the rheological properties of dough, resilience, the ability to retain carbon dioxide and absorb water, the development of gluten.
The acidity of sourdough is one of the main aspects ddt to be taken into account in assessing its quality. Acid measured ph level of from 0 to 14. Ph level determines the degree of acidity or alkalinity. Considered ddt to be a neutral ph level of water equal to 7. When ph value below 7 is acidic solution at ph value above 7 - alkaline. Consequently, the smaller is the value of ph, by an acidic medium. To leaven the optimal ph level is between 4.5 and 4.8. However, pH may be lower, but not below 3.0, depending on characteristics of the end flour product taste which we want to obtain.
Total acidity yeast depends on many factors: the quality of the flour, consistency, temperature and fermentation time, the frequency of refreshment and lactic acid bacterial strains which inhabit and its acid synthesized.
When using ph meter, we obtain the value of total acidity, which is insufficient in the case of characteristic leaven as does not give the acid balance in its composition. To get a more complete picture is necessary to carry out the titration, ddt which determines the amount of lactic and acetic acid. This is a very complex process which can be done only in a laboratory ddt through chemical analyzes. However, it is important to understand, at least in theory, that the acidity of the sourdough is not unique value.
Lactic acid and acetic acid are the most important derivatives of metabolism of lactic acid bacteria in sourdough. They serve several important functions, for example, create a flavor and aroma of a baking dish and affect the rheological properties of dough. During fermentation, during maturation dough during baking, lactic and acetic acid in combination with the ethanol produced by the yeast form numerous volatile flavoring substance, for example, aldehydes and ketones.
Lactic acid and acetic acid in the yeast must be balanced in equilibrium, which is called the fermentation. The optimal ratio is 3:1 - three parts lactic acid to one part of acetic acid.
In Italy, Technological Regulations set in accordance with which the coefficient of fermentation, ie the ratio of lactic acid and acetic acid in yeast, ddt for different types of baking has to be 3/1 to the standard use in bread and biscuits, 4/1 for baking dough-type- Panettone, Pandoro, Colombo, 0/4 to a stiff dough bread with low humidity, like Kopp Ferrarese.
- Dense medium and the low temperatures slow the metabolism and promote the synthesis of acetic acid. The type and ratio of starter acids - the coefficient of fermentation, oxidation rate and a final pH of yeast depends on the species of lactic acid bacteria present therein.
Homofermentative bacteria which form during fermentation basically the lactic acid and flavoring, some volatile acid, ethyl alcohol and carbon dioxide. For example MBC-Lactobacillus casei and Lactobacillus Plantarum, exhibit rapid production of lactic ddt acid, which significantly affects ddt the final acidity of the dough.
Heterofermentative bacteria, which lactic acid along with substantial amounts of volatile form acids, including acetic acid, ethyl alcohol, ddt carbon dioxide and other compounds causing formation of the aromatic complex. Thus, ub - Lactobacillus Brevis, Lactobacillus fructivorans Lactobacillus fermentum and a low level of oxidation. In the temperature ddt range from 25 to 35 C, they form a mainly lactic acid, and at lower temperatures ddt of 25 to 20 C - acetic acid.
Type of Lactobacillus plantarum belongs to homofermentative types of subgroups streptobaktery. The cells have the form of thick rod sizes (3-8) x (0.7-1.0) mm, while their length may vary depending on environmental conditions. Under adverse conditions occur more elongated shape of the cells. The cells are arranged singly or in short chains. Grains volutin basically do not form. Colonies of average size, dome-shaped, white. On media with chalk zone is formed around the colonies ddt dissolution of chalk. In the baking ddt industry, described species