Pediococcus
Encyclopedia
Pediococcus is a genus of Gram-positive
lactic acid bacteria
, placed within the family of Lactobacillaceae
. They usually occur in pairs or tetrads, and divide along two planes of symmetry, as do the other lactic acid cocci genera Aerococcus
and Tetragenococcus. They are purely homofermentative. Pediococcus dextrinicus has recently been reassigned to the genus Lactobacillus
.
such as Leuconostoc
and Lactobacillus
, responsible for the fermentation
of cabbage
, making it sauerkraut
.
In this process, the sugars in fresh cabbage are fermented to lactic acid
, which gives sauerkraut
a sour flavour and good keeping qualities.
Pediococcus bacteria are usually considered contaminants of beer
and wine
, although their presence is sometimes desired in beer styles such as Lambic
. Certain Pediococcus isolates produce diacetyl
which gives a butter
y or butterscotch
aroma to some wines (such as Chardonnay
) and a few styles of beer. Pediococcus species are often used in silage
inoculants. Pediococci are used as probiotics, and are commonly added as beneficial microbes in the creation of cheeses and yogurts.
Gram-positive
Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...
lactic acid bacteria
Lactic acid bacteria
The lactic acid bacteria comprise a clade of Gram-positive, low-GC, acid-tolerant, generally non-sporulating, non-respiring rod or cocci that are associated by their common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and lactic products, produce...
, placed within the family of Lactobacillaceae
Lactobacillaceae
The Lactobacillaceae are a family of lactic acid bacteria....
. They usually occur in pairs or tetrads, and divide along two planes of symmetry, as do the other lactic acid cocci genera Aerococcus
Aerococcus
Aerococcus is a genus in the phylum Firmicutes .-Etymology:The name Aerococcus derives from:Greek masculine gender noun aer, aeros , air; New Latin masculine gender noun coccus , a berry; New Latin masculine gender noun Aerococcus, air coccus.-Species:The genus contains 7 species, namely* A...
and Tetragenococcus. They are purely homofermentative. Pediococcus dextrinicus has recently been reassigned to the genus Lactobacillus
Lactobacillus
Lactobacillus is a genus of Gram-positive facultative anaerobic or microaerophilic rod-shaped bacteria. They are a major part of the lactic acid bacteria group, named as such because most of its members convert lactose and other sugars to lactic acid. They are common and usually benign...
.
Food Processing
Pediococcus is, along with other lactic acid bacteriaLactic acid bacteria
The lactic acid bacteria comprise a clade of Gram-positive, low-GC, acid-tolerant, generally non-sporulating, non-respiring rod or cocci that are associated by their common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and lactic products, produce...
such as Leuconostoc
Leuconostoc
Leuconostoc is a genus of Gram-positive bacteria, placed within the family of Leuconostocaceae. They are generally ovoid cocci often forming chains. Leuconostoc spp. are intrinsically resistant to vancomycin and are catalase-negative . All species within this genus are heterofermentative and are...
and Lactobacillus
Lactobacillus
Lactobacillus is a genus of Gram-positive facultative anaerobic or microaerophilic rod-shaped bacteria. They are a major part of the lactic acid bacteria group, named as such because most of its members convert lactose and other sugars to lactic acid. They are common and usually benign...
, responsible for the fermentation
Fermentation (biochemistry)
Fermentation is the process of extracting energy from the oxidation of organic compounds, such as carbohydrates, using an endogenous electron acceptor, which is usually an organic compound. In contrast, respiration is where electrons are donated to an exogenous electron acceptor, such as oxygen,...
of cabbage
Cabbage
Cabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
, making it sauerkraut
Sauerkraut
Sauerkraut , directly translated from German: "sour cabbage", is finely shredded cabbage that has been fermented by various lactic acid bacteria, including Leuconostoc, Lactobacillus, and Pediococcus. It has a long shelf-life and a distinctive sour flavor, both of which result from the lactic acid...
.
In this process, the sugars in fresh cabbage are fermented to lactic acid
Lactic acid
Lactic acid, also known as milk acid, is a chemical compound that plays a role in various biochemical processes and was first isolated in 1780 by the Swedish chemist Carl Wilhelm Scheele. Lactic acid is a carboxylic acid with the chemical formula C3H6O3...
, which gives sauerkraut
Sauerkraut
Sauerkraut , directly translated from German: "sour cabbage", is finely shredded cabbage that has been fermented by various lactic acid bacteria, including Leuconostoc, Lactobacillus, and Pediococcus. It has a long shelf-life and a distinctive sour flavor, both of which result from the lactic acid...
a sour flavour and good keeping qualities.
Pediococcus bacteria are usually considered contaminants of beer
Beer
Beer is the world's most widely consumed andprobably oldest alcoholic beverage; it is the third most popular drink overall, after water and tea. It is produced by the brewing and fermentation of sugars, mainly derived from malted cereal grains, most commonly malted barley and malted wheat...
and wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...
, although their presence is sometimes desired in beer styles such as Lambic
Lambic
Lambic is a very distinctive type of beer brewed only in the Pajottenland region of Belgium and in Brussels itself at the Cantillon Brewery and museum...
. Certain Pediococcus isolates produce diacetyl
Diacetyl
Diacetyl is a natural byproduct of fermentation. It is a vicinal diketone with the molecular formula C4H6O2...
which gives a butter
Butter
Butter is a dairy product made by churning fresh or fermented cream or milk. It is generally used as a spread and a condiment, as well as in cooking applications, such as baking, sauce making, and pan frying...
y or butterscotch
Butterscotch
Butterscotch is a type of confectionery whose primary ingredients are brown sugar and butter, although other ingredients such as corn syrup, cream, vanilla, and salt are part of some recipes...
aroma to some wines (such as Chardonnay
Chardonnay
Chardonnay is a green-skinned grape variety used to make white wine. It is originated from the Burgundy wine region of eastern France but is now grown wherever wine is produced, from England to New Zealand...
) and a few styles of beer. Pediococcus species are often used in silage
Silage
Silage is fermented, high-moisture fodder that can be fed to ruminants or used as a biofuel feedstock for anaerobic digesters. It is fermented and stored in a process called ensiling or silaging, and is usually made from grass crops, including corn , sorghum or other cereals, using the entire...
inoculants. Pediococci are used as probiotics, and are commonly added as beneficial microbes in the creation of cheeses and yogurts.
See also
- Pediococcus acidilacticiPediococcus acidilacticiPediococcus acidilactici is a species of gram positive coccus that is often found in pairs or tetrads. Pediococcus acidilactici is a homo-fermentative bacterium that can grow in a wide range of pH, temperature and osmotic pressure, therefore being able to colonize the digestive tract...
- LactobacillusLactobacillusLactobacillus is a genus of Gram-positive facultative anaerobic or microaerophilic rod-shaped bacteria. They are a major part of the lactic acid bacteria group, named as such because most of its members convert lactose and other sugars to lactic acid. They are common and usually benign...
- Lactic acid bacteriaLactic acid bacteriaThe lactic acid bacteria comprise a clade of Gram-positive, low-GC, acid-tolerant, generally non-sporulating, non-respiring rod or cocci that are associated by their common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and lactic products, produce...
- FirmicutesFirmicutesThe Firmicutes are a phylum of bacteria, most of which have Gram-positive cell wall structure. A few, however, such as Megasphaera, Pectinatus, Selenomonas and Zymophilus, have a porous pseudo-outer-membrane that causes them to stain Gram-negative...
- SauerkrautSauerkrautSauerkraut , directly translated from German: "sour cabbage", is finely shredded cabbage that has been fermented by various lactic acid bacteria, including Leuconostoc, Lactobacillus, and Pediococcus. It has a long shelf-life and a distinctive sour flavor, both of which result from the lactic acid...