Fermentation with Lactic Acid Bacteria

Kim, Y. J., and Liu, R. H. 2002. Increase of conjugated linoleic acid content in milk by fermentation with lactic acid bacteria. J. Food Sci., 67,1731-1737. 

Vutanen, T., Pihlanto, A., Akkanen, S., Korhonen, H. (2007). Development of antioxidant activity in milk whey during fermentation with lactic acid bacteria. Journal of Applied Microbiology, 102,106-115. 

Lactose is readily fermented by lactic acid bacteria, especially Lactococcus spp. and Lactobacillus spp., to lactic acid, and by some species of yeast, e.g. Kluyveromyces spp., to ethanol (Figure 2.27). Lactic acid may be used as a food acidulant, as a component in the manufacture of plastics, or converted to ammonium lactate as a source of nitrogen for animal nutrition. It can be converted to propionic acid, which has many food applications, by Propionibacterium spp. Potable ethanol is being produced commercially from lactose in whey or UF permeate. The ethanol may also be used for industrial purposes or as a fuel but is probably not cost-competitive with ethanol produced by fermentation of sucrose or chemically. The ethanol may also be oxidized to acetic acid. The mother liquor remaining from the production of lactic acid or ethanol may be subjected to anaerobic digestion with the production of methane (CH4) for use as a fuel several such plants are in commercial use. 

Cultured buttermilk is manufactured by fermenting whole milk, reconstituted nonfat dry milk, partly skimmed milk, or skim milk with lactic acid bacteria. Most commercial cultured buttermilk is made from skim milk. Mixed strains of lactic streptococci are used to produce lactic acid and leuconostocs for development of the characteristic diacetyl flavor and aroma. Buttermilk is similar to skim milk in composition, except that it contains about 0.9% total acid expressed as lactic acid. The percentage of lactose normally found in skim milk is reduced in proportion to the percentage of lactic acid in the buttermilk. According to White (1978), the fat content of buttermilk usually varies from 1 to 1.8%, sometimes in the form of small flakes or granules to simulate churned buttermilk, the by-product of butter churning. Usually 0.1% salt is added. 

Together with proteins and peptides, amino acids constitute the main components of the nitrogenous fraction of musts and wines. They are also the most studied and best known nitrogenated components in wines. Free amino acids in musts are of paramount importance. They constitute a source of nitrogen for yeasts in alcoholic fermentation, for lactic acid bacteria in malolactic fermentation, and can also be a source of aromatic compounds (Kosir and Kidric, 2001). In certain cases, some amino acids... 

Another component important for the beer flavour in this context is obtained by the fermentation of cereals with lactic acid bacteria. Flavour substances produced in this way supplement the beer flavour obtained by the yeast fermentation in a very positive way [24[. 

Chien, H.L. H.Y. Huang C.C. Chou. Transformation of isoflavone phytoestrogens during the fermentation of soymilk with lactic acid bacteria and bifidobacteria. Food Microbiol. 2006, 23, 772-77%. 

Cereal flours Fermentation of sourdough with lactic acid bacteria 25 Peptides (8—57 amino acid residues) Coda et al. (2012)... 

It should be emphasised that the cured colour can be obtained without starter culture and also that a minimum level of either nitrate or nitrite is needed to obtain the cured colour. However, Micrococcaceae, and particularly Staphylococcus, ensure the utilisation of the curing agents and stabilise the colour because of catalase formation. Colour development is accelerated in comparison to fermentation, relying on the indigenous flora or fermentation carried out with lactic acid bacteria alone. 

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). 

Other types of fermenters have been developed for specific applications. Anaerobic bioreactors are used when microorganisms do the conversions in the absence of oxygen. Examples are the acetone-butanol-ethanol (ABE) fermentation with Clostridium species, the production of lactic acid with lactic acid bacteria, and bioethanol fermentation with Saccharomyces cerevisiae. Because of the need for large volumes with these low-cost products, and the ease of construction, these... 

Mozzi, F., Ortiz, M.E., Bleckwedel, J., et al. (2013) Metabolomics as a tool for the comprehensive understanding of fermented and functional foods with lactic acid bacteria. Food Res Int 54, 1152-1161. 

In addition to alcohoHc fermentation, a malolactic fermentation by certain desirable strains of lactic acid bacteria needs to be considered. Occasionally, wild strains produce off-flavors. Malolactic fermentation is desirable in many red table wines for increased stabiUty, more complex flavor, and sometimes for decreased acidity. Selected strains are often added toward the end of alcohoHc fermentation. AH the malic acid present is converted into lactic acid, with the resultant decrease of acidity and Hberation of carbon dioxide. Obviously this has more effect on the acidity the more malic acid is present, and this is the case in wine from underripe, too-tart grapes. Once malolactic fermentation has occurred, it does not recur unless another susceptible wine is blended. 

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