Acetic acid Bacteria Control

Du Toit, W.J. and Pretorius, I.S. 2002. The occurrence, control and esoteric effect of acetic acid bacteria in winemaking. Ann. Microbiol. 52, 155-179. 

Sengun, I. K., Karabiyikli, S. (2011). Review importance of acetic acid bacteria in food industry. Food Control, 22,647-656. 

Although sulfite may not be as inhibitory to native yeasts as once believed, prefermentation additions are, nevertheless, crucial in the control of native lactic acid bacteria (LAB) and acetic acid bacteria (AAB). Failure to utilize the agent, at least in the recent history of some California red wine fermentations, has been one step implicated in rapid proliferation of spoilage LAB, the metabolites of which are strongly inhibitory toward both indigeneous and inoculated strains of Saccharomyces sp. (see Sec 1.4.1). 

Bacteria. In addition to the many chemical and physical aspects of foods that have been covered in this section, there are the bacteriological reactions. Some are desirable, such as the action of yeast in leavening, and in beers and wines mold in making cheese acetic acid bacteria in vinegar and acidophilus in yogurt. But others are undesirable and can cause great discomfort and even death included in the latter group are Staphylococcus, Streptococcus, Salmonella, and the dreaded, Clostridium botulinum. Undesirable bacteria can be controlled by—... 

Acetic acid bacteria are very prevalent in nature and are well adapted to growth in sugar-rich and alcohol-rich environments. Wine, beer and cider are natural habitats of these bacteria when production and storage conditions are not correctly controlled. Their quality is clearly lowered, except in the case of certain very particular beers. 

Sulfur dioxide is also active on acetic acid bacteria but additional studies on this subject are needed. These bacteria resist relatively high concentrations. In the winery, acetic acid bacteria are most effectively prevented by avoiding contact with oxygen in the air and controlling temperature in the winery. 

The predominant bacteria were A. pasteurianus, and a novel species was found and named A. ghanensis (Cleenwerck et al. 2007), A. senegalensis (Camu et al. 2007 Ndoye et al. 2007), and A. fabarum (Cleenwerck et al. 2008). Acetic acid can penetrate the cocoa beans, kill the embryo, and decompose their internal structure to form flavor and color development. Thus, acetic acid bacteria have an important function during cocoa bean fermentation that contributes to the formation of cocoa flavor precursors and the control of the cocoa bean fermentation process. 

Mateo E, Torija Ml, Mas A, Bartowsky EJ (2014) Acetic acid bacteria isolated from grapes of South Australian vineyards. Int J Food Microbiol 178 98-106 McCutcheon IP, Moran NA (2007) Parallel genomic evolution and metabolic interdependence in an ancient symbiosis. Proc Natl Acad Sci USA 104 19392-19397 Miller T (2011) Paratransgenesis as a potential tool for pest control review of applied arthropod symbiosis. J Appl Entomol 135 474—478... 

The most important type of mixed solution is a buffer, a solution in which the pH resists change when small amounts of strong acids or bases are added. Buffers are used to calibrate pH meters, to culture bacteria, and to control the pH of solutions in which chemical reactions are taking place. They are also administered intravenously to hospital patients. Human blood plasma is buffered to pH = 7.4 the ocean is buffered to about pH = 8.4 by a complex buffering process that depends on the presence of hydrogen carbonates and silicates. A buffer consists of an aqueous solution of a weak acid and its conjugate base supplied as a salt, or a weak base and its conjugate acid supplied as a salt. Examples are a solution of acetic acid and sodium acetate and a solution of ammonia and ammonium chloride. 

The most obvious method of controlling microbial wine disorders is to prevent contamination of the wine. Yeasts which have been used for the alcoholic fermentation must be removed or inactivated before bottling. The same restriction applies to acetic- or lactic acid bacteria which may have entered the wine during or after fermentation. 

Landete, J.M., Pardo, I. Ferrer, S. (2007b). Biogenic amine production by lactic acid bacteria, acetic bacteria and yeast isolated from wine. Food Control, 18, 1569-1574. 

Until a decade ago, the available experimental data could be used to support either point of view. The major reason was that carefully controlled studies had not been conducted to prove or disprove either contention. At that time, McCarty and McKinney (17,18) published the results of their work in which they investigated the toxicity of acetic acid to methane bacteria. Acetic acid is the most prevalent acid produced during anaerobic waste treatment (19). 

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