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Fructilactobacillus Sanfranciscensis
''Fructilactobacillus sanfranciscensis'' is a heterofermentative species of lactic acid bacteria which, through the production mainly of lactic and acetic acids, helps give sourdough bread its characteristic taste. It is named after San Francisco, where sourdough was found to contain the variety, though it is dominant in Type I sourdoughs globally. In fact, ''F. sanfranciscensis'' has been used in sourdough breads for thousands of years, and is used in 3 million tons of sourdough goods yearly. For commercial use, specific strains of ''F. sanfranciscensis'' are grown on defined media, freeze-dried, and shipped to bakeries worldwide. Overview ''Fructilactobacillus sanfranciscensis'' was first known to be isolated in 1971 by Kline and Sugihara. As lactic acid bacteria, the strains are Gram-positive, slender, rod-shaped, nonsporulating, and non-motile. They are also obligately heterofermentative, meaning that they can convert hexose sugars into not just lactic acid, but also et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactic Acid Bacteria
Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical ( cocci) bacteria that share common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and milk products, produce lactic acid as the major metabolic end product of carbohydrate fermentation, giving them the common name lactic acid bacteria (LAB). Production of lactic acid has linked LAB with food fermentations, as acidification inhibits the growth of spoilage agents. Proteinaceous bacteriocins are produced by several LAB strains and provide an additional hurdle for spoilage and pathogenic microorganisms. Furthermore, lactic acid and other metabolic products contribute to the organoleptic and textural profile of a food item. The industrial importance of the LAB is further evidenced by their generally recognized as safe (GRAS) status, due to their ubiquitous appearance in food and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sourdough Bread
Sourdough is a type of bread that uses the fermentation, fermentation by naturally occurring yeast and lactobacillaceae, lactobacillus bacteria to raise the dough. In addition to leavening the bread, the fermentation process produces lactic acid, which gives the bread its distinctive sour taste and improves its keeping-qualities. History Sourdough is one of the most ancient forms of bread. It was the standard method of breadmaking for most of human history until the Middle Ages, when it was replaced by barm. Barm, in turn, was replaced in the late 19th and early 20th centuries by industrially produced baker's yeast. The ''Encyclopedia of Food Microbiology'' states: "One of the oldest sourdough breads dates from 3700 BCE and was excavated in Switzerland, but the origin of sourdough fermentation likely relates to the origin of agriculture in the Fertile Crescent and Egypt several thousand years earlier", and "Bread production relied on the use of sourdough as a leavening agent for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Francisco
San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of 2024, San Francisco is the List of California cities by population, fourth-most populous city in the U.S. state of California and the List of United States cities by population, 17th-most populous in the United States. San Francisco has a land area of at the upper end of the San Francisco Peninsula and is the County statistics of the United States, fifth-most densely populated U.S. county. Among U.S. cities proper with over 250,000 residents, San Francisco is ranked first by per capita income and sixth by aggregate income as of 2023. San Francisco anchors the Metropolitan statistical area#United States, 13th-most populous metropolitan statistical area in the U.S., with almost 4.6 million residents in 2023. The larger San Francisco Bay Area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Growth Medium
A growth medium or culture medium is a solid, liquid, or semi-solid designed to support the growth of a population of microorganisms or cells via the process of cell proliferation or small plants like the moss ''Physcomitrella patens''. Different types of media are used for growing different types of cells. The two major types of growth media are those used for cell culture, which use specific cell types derived from plants or animals, and those used for microbiological culture, which are used for growing microorganisms such as bacteria or fungi. The most common growth media for microorganisms are nutrient broths and agar plates; specialized media are sometimes required for microorganism and cell culture growth. Some organisms, termed fastidious organisms, require specialized environments due to complex nutritional requirements. Viruses, for example, are obligate intracellular parasites and require a growth medium containing living cells. Types The most common growth media ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freeze Dry
Freeze drying, also known as lyophilization or cryodesiccation, is a low temperature Food drying, dehydration process that involves freezing the product and lowering pressure, thereby removing the ice by Sublimation (phase transition), sublimation. This is in contrast to dehydration by most conventional methods that evaporate water using heat. Because of the low temperature used in processing, the rehydrated product retains many of its original qualities. When solid objects like strawberries are freeze dried the original shape of the product is maintained. If the product to be dried is a liquid, as often seen in pharmaceutical applications, the properties of the final product are optimized by the combination of excipients (i.e., inactive ingredients). Primary applications of freeze drying include biological (e.g., bacteria and yeasts), biomedical (e.g., surgical transplants), food processing (e.g., coffee), and Food preservation, preservation. History The Inca were freeze dry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive Bacteria
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is used by microbiologists to place bacteria into two main categories, gram-positive (+) and gram-negative (−). Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria retain the crystal violet stain used in the test, resulting in a purple color when observed through an optical microscope. The thick layer of peptidoglycan in the bacterial cell wall retains the stain after it has been fixed in place by iodine. During the decolorization step, the decolorizer removes crystal violet from all other cells. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sourdough Starter
Sourdough is a type of bread that uses the fermentation by naturally occurring yeast and lactobacillus bacteria to raise the dough. In addition to leavening the bread, the fermentation process produces lactic acid, which gives the bread its distinctive sour taste and improves its keeping-qualities. History Sourdough is one of the most ancient forms of bread. It was the standard method of breadmaking for most of human history until the Middle Ages, when it was replaced by barm. Barm, in turn, was replaced in the late 19th and early 20th centuries by industrially produced baker's yeast. The ''Encyclopedia of Food Microbiology'' states: "One of the oldest sourdough breads dates from 3700 BCE and was excavated in Switzerland, but the origin of sourdough fermentation likely relates to the origin of agriculture in the Fertile Crescent and Egypt several thousand years earlier", and "Bread production relied on the use of sourdough as a leavening agent for most of human history; the us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaven
In cooking, a leavening agent () or raising agent, also called a leaven () or leavener, is any one of a number of substances used in doughs and batter (cooking), batters that cause a Effervescence, foaming action (gas bubbles) that lightens and softens the mixture. An alternative or supplement to leavening agents is mechanical action by which air is incorporated (i.e. kneading). Leavening agents can be biological or synthetic chemical compounds. The gas produced is often carbon dioxide, or occasionally hydrogen. When a dough or batter is mixed, the starch in the flour and the water in the dough form a Matrix (biology), matrix (often supported further by proteins like gluten or polysaccharides, such as pentosans or xanthan gum). The starch then starch gelatinization, gelatinizes and sets, leaving gas bubbles that remain. Biological leavening agents * ''Saccharomyces cerevisiae'' producing carbon dioxide found in: ** baker's yeast ** Beer barm (unpasteurised—live yeast) ** gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yeast
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom (biology), kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitute 1% of all described fungal species. Some yeast species have the ability to develop multicellular characteristics by forming strings of connected budding cells known as pseudohyphae or false hyphae, or quickly evolve into a Multicellular organism, multicellular cluster with specialised Organelle, cell organelles function. Yeast sizes vary greatly, depending on species and environment, typically measuring 3–4 micrometre, μm in diameter, although some yeasts can grow to 40 μm in size. Most yeasts reproduce asexual reproduction, asexually by mitosis, and many do so by the asymmetric division process known as budding. With their single-celled growth habit, yeasts can be contrasted with Mold (fungus), molds, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maltose
} Maltose ( or ), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two-unit member of the amylose homologous series, the key structural motif of starch. When beta-amylase breaks down starch, it removes two glucose units at a time, producing maltose. An example of this reaction is found in germinating seeds, which is why it was named after malt. Unlike sucrose, it is a reducing sugar. History Maltose was discovered by Augustin-Pierre Dubrunfaut, although this discovery was not widely accepted until it was confirmed in 1872 by Irish chemist and brewer Cornelius O'Sullivan. Its name comes from malt, combined with the suffix ' -ose' which is used in names of sugars. Structure and nomenclature Carbohydrates are generally divided into monosaccharides, oligosaccharides, and polysaccharides depending on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biochemistry)
In chemistry, the term substrate is highly context-dependent. Broadly speaking, it can refer either to a chemical species being observed in a chemical reaction, or to a surface on which other chemical reactions or microscopy are performed. In the former sense, a reagent is added to the ''substrate'' to generate a product through a chemical reaction. The term is used in a similar sense in synthetic and organic chemistry, where the substrate is the chemical of interest that is being modified. In biochemistry, an enzyme substrate is the material upon which an enzyme acts. When referring to Le Chatelier's principle, the substrate is the reagent whose concentration is changed. ;Spontaneous reaction : :*Where S is substrate and P is product. ;Catalysed reaction : :*Where S is substrate, P is product and C is catalyst. In the latter sense, it may refer to a surface on which other chemical reactions are performed or play a supporting role in a variety of spectroscopic and mic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosomal RNA
Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal DNA (rDNA) and then bound to ribosomal proteins to form SSU rRNA, small and LSU rRNA, large ribosome subunits. rRNA is the physical and mechanical factor of the ribosome that forces transfer RNA (tRNA) and messenger RNA (mRNA) to process and Translation (biology), translate the latter into proteins. Ribosomal RNA is the predominant form of RNA found in most cells; it makes up about 80% of cellular RNA despite never being translated into proteins itself. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins, though this ratio differs between Prokaryote, prokaryotes and Eukaryote, eukaryotes. Structure Although the primary structure of rRNA sequences can vary across organisms, Base pair, base-pairing within these sequ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
