Sourdough bread

Introduction. The technique of biocatalysis has been used for thousands of years in the production of various food products including bread ( sourdough ) the fermentation of sugar from fruit and fruit pulp to produce alcoholic beverages the processing of milk to produce cheese, yoghurt, and other products the production of vinegar and sauerkraut and many other products. 

Sourdough is a mixture of flour and water, containing yeasts and lactic acid bacteria, used as starter culture to leaven bread. Sourdoughs are produced at... 

Lactic acid [50-21-5] (2-hydroxypropanoic acid), CH CHOHCOOH, is the most widely occurring hydroxycarboxylic acid and thus is the principal topic of this article. It was first discovered ia 1780 by the Swedish chemist Scheele. Lactic acid is a naturally occurring organic acid that can be produced by fermentation or chemical synthesis. It is present ia many foods both naturally or as a product of in situ microbial fermentation, as ia sauerkraut, yogurt, buttermilk, sourdough breads, and many other fermented foods. Lactic acid is also a principal metaboHc iatermediate ia most living organisms, from anaerobic prokaryotes to humans. 

Fumaric acid breaks the sulfur-to-sulfur bonds in the elastic protein gluten in bread doughs. This makes the doughs more machine-able. It also is a key ingredient in rye and sourdough breads—it makes them sourer. 

Bacteria in miik feed on iactose (miik sugar) to produce iactic acid, another carboxyiic acid. Under controiied conditions, this process gives yogurt. Simiiariy, the proper combination of yeast and bacteria acts on flour to form just enough iactic acid and acetic acid (CH3 CO2 H) to give sourdough bread its distinctive tang. 

Thiele, C., Ganzle, M.G., Vogel, R.F. 2002. Contribution of sourdough lactobacilli, yeasts, and cereal enzymes to the generation of amino acids in dough relevant for bread flavor. Cereal Chem 79 45-51. 

E., and Gobbetti, M. 2004. Sourdough bread made from wheat and nontoxic flours and started with selected Lactobacilli is tolerated in celiac patients. Appl Environ Microbiol 70(2) 1088-1096. 

Well known in the supermarkets and health food stores, Country Life Bakery began focusing on wholemeal and sourdough and in the last 9 years has increasingly turned its attention to organic to satisfy customer demand. Its breads are sent interstate now and to Southeast Asia, mainly Singapore. 

Sourdough has long been known to improve the shelf life of bread and bakery products, primarily because of the existence of lactic acid produced by lactic acid bacteria (Lavermicocca, Valerio, and Visconti, 2003). 

Sourdough is also classified as a natural preservative and has long been known to improve the shelf lives of bread and bakery products. Phenyllactic acid (PLA) has been found in cultures of Lactococcus plantation with antifungal activity in sourdough breads. Relevant amounts of PLA naturally occur in several honeys from different geographical areas. It is nontoxic for human and animal cells and may also be safely used in food. However, information is needed on its effect on rheology and flavor,... 

A REVIEW OF THE APPLICATION OF SOURDOUGH TECHNOLOGY TO WHEAT BREADS... 

III. Positive Effects of Sourdough on Wheat Bread Quality... 

V. Effect of Sourdough Incorporation on Bread Dough Structure... 

III. POSITIVE EFFECTS OF SOURDOUGH ON WHEAT BREAD QUALITY... 

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