NATAMYCIN - Natural Preservative

NATAMYCIN [E235] (Pimaricin) is an antimycotic product which has a broad and effective action. It not only inhibits the growth of different moulds and yeasts, but also inhibits the production of their toxin. Commercial Natamycin contains 50% of the active substance. Small quantities of Natamycin can inhibit all moulds and yeasts, which cause food spoilage. Natamycin has no effect on bacteria, so it does not prevent the natural maturing process of yogurt, cheese, fresh ham, sausage, etc.

Physical characteristic: Natamycin is a white to yellow flavourless, odourless crystalline powder. It is very stable in its crystal form. The solubility of Natamycin is very low in water and in most organic solvents. Only 50mg Natamycin can be dissolved in pure water at room temperature. This low solubility will makes it very suitable for use on the food surface. Natamycin will stay on surface of food, where most moulds and yeasts may grow, but does not influence the natural course of fermentation inside.

Microbiological characteristic: Natamycin can control almost all yeasts and moulds but does not affect bacteria, viruses or other micro-organisms.

Stability: Many factors can influence the stability of Natamycin: acidity (PH value), temperature, light, oxygen, heavy metals, etc.

Usage: Food preservative. Ideal results can be achieved by using Natamycin on the exposed surface of the food where the moulds and yeasts may grow. This is especially useful for cheese manufacture, since mould growth is prevented, while the cheese ripening bacteria will grow and metabolize normally. The product should be stored in a dry, cool place, in original sealed containers, and away from direct sunlight. Such as in beverage drinks; dosage of Natamycin is 15-40 ppm.

Packaging: 500 grams

Shelf life: two years in cool (0-10°C), dry conditions, away from direct sunlight in original unopened packs.

NISIN - Natural Preservative

NISIN [E234] is a food preservative which is well-known and accepted around the world.

Nisin can be used to extend or maintain shelf life of a wide range of heat-treated or acidic foods, and as part of a multifactorial protective system nisin can reduce or control Gram-positive bacteria pathogens. It is a natural food preservative which is highly efficient, safe, and has no side-effects. In addition, it has excellent solubility and stability in foods. It is not effective against Gram-negative bacteria. Yeasts, or moulds.

Application: Nisin can be used in a wide range of heat processed foods. These include: fresh milk, processed cheese and other dairy products, pasteurised liquid egg, processed meat, seafood, canned food, fruit drinks, plant protein drinks, baked products, instant food, beer, wine etc. It can also be used as a preservative in gelatin processing, cosmetics, drugs and health products.

Usage: Recommend dosage for Nisin, such as in beverage drink products is 50-100 ppm. If the product is high acid, the dosage can be decreased to 30-50 ppm.

Packaging: 500 grams

Shelf life: two years in cool (0-10°C), dry conditions, away from direct sunlight in original unopened packs.

Polylysine - Natural Preservative in Food Products

Polylysine
Polylysine (ε-Poly-L-lysine)is a small polypeptide of the essential amino acid L-Lysine that is produced by bacterial fermentation. ε-Poly-L-lysine is used as a natural preservative in food products (see also: Polylysine in food).


Chemical structure & function
ε-Polylysine is a homo-polypeptide of approximately 25 ~ 30 L-Lysine residues. Epsilon (ε) refers to the linkage of the lysine molecules. In contrast to normal peptide bond that is linked by the alpha-carbon group, the lysine amino acids are molecularly linked by the epsilon amino group and the alpha carboxyl group.


ε-Polylysine belongs to the group of cationic surfactants. In water, ε-polylysine contains a positively charged hydrophilic (amino) group and a hydrophobic (methylene) group. Cationic surface-active compounds have the ability to inhibit the growth of microorganisms. According to Japanese researchers, ε-polylysine is absorbed electrostatically to the cell surface of the bacteria, followed by a stripping of the outer membrane. This eventually leads to the abnormal distribution of the cytoplasm causing damage to the bacterial cell.


Properties
ε-Polylysine is a natural substance made from streptomyces albulus metabolism. High potency ε -Polylysine is a hygroscopic, light yellow power. It is soluble in water, slightly soluble in ethanol, insoluble in organic solvent such as ethyl acetate, ether, etc.. The molecular of ε -Polylysine is a straight chain polymer of lysine. It can decompose to lysine in human body, and can be completely digested and absorpted , but has no poisnous side-effects.

ε-Polylysine can inhibit the growth of Gram(+) and Gram(-) bacteria , yeast, mould, virus, ect., especially inhibit the Gram(-) bacteria which can't be easily inhibited by other preservatives,such as E coli, Salmonella,and thermophilic bacillus , etc. Its activity is not affected by PH value , and stable when heated (120°C for 20min). It is widelly used as a highly efficient and safe food preservative.



Production
Production of polylysine by natural fermentation is only observed in Streptomyces strains. The strain Streptomyces albulus is most often found in literature studies and is also used for the commercial production of ε-polylysine.


History
The production of ε-polylysine by natural fermentation was first described by Japanese researchers Shoji Shima and Heiichi Sakai in 1977.


Since the late 1980’s, polylysine has been approved by the Japanese “Ministry of Health, Labour and Welfare” as a preservative in food. In January 2004, polylysine became GRAS (Generally Recognized As Safe) certified in the United States.


Polylysine in food
Polylysine is commercially used as a food preservative in Japan, the republic of Korea and in the USA. Food products containing polylysine are mainly found in Japan. The use of polylysine is common in food applications like: boiled rice, cooked vegetables, soups, noodles and sliced fish (sushi).


Literature studies have reported an antimicrobial effect of ε-polylysine against yeast, fungi, gram-positive bacteria and gram-negative bacteria


Polylysine has a light yellow appearance and is slightly bitter in taste whether in powder or liquid form.


Polylysine was generally recognized as a safe food preservative by FDA in October,2003. It is widely used in food industry. In food application, it is usually applied with alcohol, organic acids, or glyceride, etc.. It can be used in cooked rice, cakes, snacks, noodles, drinks, brewing, meat products, canned food, etc. Recommend dosage from 35 to150 ppm for food processing.

Biology and Health effects
ε-Polylysine was found to be non-toxic at high levels in acute animal studies and was not mutagenic in bacterial reversion assays. Polylysine is “Generally Recognized As Safe” (GRAS) by the FDA.


References
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Nisin - A Choice of Natural Food Preservative

Nisin is a polycyclic peptide antibacterial with 34 amino acid residues used as a food preservative. It contains the uncommon amino acids lanthionine (Lan), methyllanthionine (MeLan), didehydroalanine (Dha) and didehydroaminobutyric acid (Dhb). These unusual amino acids are introduced by posttranslational modification of the precursor peptide. In these reactions a ribosomally synthesized 57-mer is converted to the final peptide. The unsaturated amino acids originate from serine and threonine, and the enzyme-catalysed addition of cysteine residues to the didehydro amino acids result in the multiple thioether bridges.
Nisin is produced by fermentation using the bacterium Lactococcus lactis. Commercially, it is obtained from the culturing of Lactoccus lactis on natural substrates, such as milk or dextrose, and is not chemically synthesized. It is used in processed cheese, meats, beverages, etc. during production to extend shelf life by suppressing Gram-positive spoilage and pathogenic bacteria. While most bacteriocins generally inhibit only closely related species, Nisin is a rare example of a "broad-spectrum" bacteriocin effective against many Gram-positive organisms, including lactic acid bacteria (commonly associated with spoilage), Listeria monocytogenes (a known pathogen), etc. However, when coupled with the chelator EDTA, Nisin has also been known to inhibit Gram-negative bacteria, as well. Nisin is soluble in water and can be effective at levels nearing the parts per billion range. In foods, it is common to use Nisin at levels ranging from ~1-25ppm, depending on the food type and regulatory approval. Due to its naturally selective spectrum of activity, it is also employed as a selective agent in microbiological media for the isolation of gram-negative bacteria, yeast, and moulds. Subtilin and Epidermin are related to Nisin. All are members of a class of molecules known as lantibiotics.
As a food additive, nisin has E number E234.

Nisin - food natural preservative useful

Nisin is a polycyclic peptide antibacterial with 34 amino acid residues used as a food preservative. It contains the uncommon amino acids lanthionine (Lan), methyllanthionine (MeLan), didehydroalanine (Dha) and didehydroaminobutyric acid (Dhb). These unusual amino acids are introduced by posttranslational modification of the precursor peptide. In these reactions a ribosomally synthesized 57-mer is converted to the final peptide. The unsaturated amino acids originate from serine and threonine, and the enzyme-catalysed addition of cysteine residues to the didehydro amino acids result in the multiple thioether bridges.
Nisin is produced by fermentation using the bacterium Lactococcus lactis. Commercially, it is obtained from the culturing of Lactoccus lactis on natural substrates, such as milk or dextrose, and is not chemically synthesized. It is used in processed cheese, meats, beverages, etc. during production to extend shelf life by suppressing Gram-positive spoilage and pathogenic bacteria. While most bacteriocins generally inhibit only closely related species, Nisin is a rare example of a "broad-spectrum" bacteriocin effective against many Gram-positive organisms, including lactic acid bacteria (commonly associated with spoilage), Listeria monocytogenes (a known pathogen), etc. However, when coupled with the chelator EDTA, Nisin has also been known to inhibit Gram-negative bacteria, as well. Nisin is soluble in water and can be effective at levels nearing the parts per billion range. In foods, it is common to use Nisin at levels ranging from ~1-25ppm, depending on the food type and regulatory approval. Due to its naturally selective spectrum of activity, it is also employed as a selective agent in microbiological media for the isolation of gram-negative bacteria, yeast, and moulds. Subtilin and Epidermin are related to Nisin. All are members of a class of molecules known as lantibiotics.
As a food additive, nisin has E number E234.

Probiotics - bacteria for life !

What Are Probiotics ?


It may come as a surprise, but not all bacteria are bad for you. It’s common to hear news reports about harmful bacteria (pathogens) these days, and most of us are familiar with some of their names-Listeria moncytogenes, Clostridium botulinum and various strains of Salmonella, for instance. But other families of bacteria are not injurious to human health, and may, in fact, provide some health benefits, particularly those in the Lactobacillus and Bifidobacterium genera. Probiotic means “for life.” The definition of a probiotic has changed over time, but these days, the generally accepted definition is the one issued by the Food and Agricultural Organization (FAO) of the United Nations and the World Health Organization (WHO). Probiotics are “live microorganisms which when administered in adequate amounts, confer a beneficial health effect on the host.” These microorganisms do not promote or cause disease. They comprise multiple species and subspecies of bacteria, as well as one species of yeast, Saccharomyces, but note that not all live, non-pathenogenic microorganisms are probiotics.


Probiotics are just beginning to catch on in the U.S., but they’ve been a bigger deal in Europe and Asia for years. For instance, Dannon’s Activia, a recent introduction in the U.S., has been sold overseas since 1987. Considering that people of other nations tend to turn to foods and natural remedies for good health, while Americans rely far more heavily on pills and medications, this is not surprising. In fact, according to the International Probiotics Association, Japanese grocery store shelves are stocked with dozens of probiotic-containing foods, while in Europe, yogurts and fermented milks are the most widely-consumed probiotic products. In the U.S., consumption of probiotic supplements far outweighs consumption of foods containing these beneficial bacteria.

Due to the vast number of cells involved in probiotics, counts for these bacteria in any product tend to be very high, often numbering in the billions. While many foods containing probiotics do not list specific bacterial counts, it isn’t uncommon to see numbers of five to ten billion associated with a single serving of probiotic-containing foods. In general, numbers of probiotic bacteria are expressed as a CFU count.


CFU stands for “colony forming unit.” A CFU is a viable cell. Viable cells are live cells that have been rendered dormant and must be reactivated after ingestion on their journey toward the intestinal tract. Consumers are likely to find viable cells in freeze-dried powders that might be in probiotic capsule supplements, for example; live cells are often found in probiotic-containing dairy foods.


You may also see the terms “prebiotics” and “synbiotics.”

Prebiotics are indigestible ingredients in foods that are thought to assist the growth and/or activity of certain probiotics, especially those in the bifidobacteria family. Two of the more commonly-found prebiotics are inulin and fructo-oligosaccharides (FOS).

Synbiotics are supplements or functional foods that contain both a prebiotic and a probiotic (a functional food is one that may provide a health benefit beyond basic nutrition; the concept is based on the ancient Hippocratic concept of food as medicine). The thought is that there are certain combinations of prebiotics and probiotics that can work together especially well.


Neither prebiotics nor synbiotics is covered in this article.

Natamycin : what's useful for today food additive ?

Natamycin has been used for decades in the food industry as a hurdle to fungal outgrowth in dairy products, meats, and other foods. Potential advantages for the usage of natamycin might include the replacement of traditional chemical preservatives, a neutral flavor impact, and less dependence on pH for efficacy, as is common with chemical preservatives. It may be applied by spraying a liquid suspension, by dipping the product in an aqueous suspension (known as a "brine"), or by mixing it into the product in a powdered form along with cellulose (a known "anti-caking" agent) on whole, shredded, or soft cheeses. While not currently approved for use on meats in the United States, some countries allow natamycin to be applied to the surface of dry and fermented sausages to prevent mold growth on the casing. Also, natamycin is approved for various dairy applications in the United States. More specifically, natamycin is commonly used in products such as cottage cheese, sour cream, and yogurt. As a food additive, it has E number E235.

Source: From Wikipedia, the free encyclopedia