Nisin is a polypeptide produced by some strains of Streptococcus Lactic (later termed Lactococcus lactis subspecies lactis ) strain, which contains 34 amino acids.
Technical Date Sheet
Nisin is a polypeptide produced by some strains of Streptococcus Lactic (later termed Lactococcus lactis subspecies lactis ) strain, which contains 34 amino acids. It is a natural anti-microbial agent and used as a natural food preservative with high efficiency, nontoxic, no harm to humans and be free from side effects and is deemed to be a GRAS (Generally Recognised as Safe) substance. Nisin is soluble in aqueous environments and most stable in acid conditions.
Nisin possesses anti-microbial activity against a wide range of Gram-positive bacteria, particularly those that produce spores. It inhibits certain strains of the food pathogen, such as Clostridium botulinum, Staphylococcus aureus, Streptococcus hemolyticus, Listeria monocytogenes, Bacillus stearothermophilus, Bacillus subtilis and some others. Nisin is used as a food preservative in a number of thermal processed foods, particularly in dairy products, canned foods, plant protein foods and cured meat etc.
Nisin is applied as a food preservative in over 50 countries and areas all over the world. Up to now, the products of Nisin not only supply in China domestic markets but also batch-bulk enter into international markets, warmly welcomed by the consumers.
Nisin is an effective anti-microbial agent, using Nisin as food preservative can reduce the temperature of the heat processing and shorten the time of the heat processing required, so that the use Nisin can reduce the energy consumption of the process. It can enhance food product quality, and significantly extend the shelf life of food. It can replace or partial replace chemical preservatives and meet consumer demand for food preserved with natural ingredients. It also can control of pathogenic as part of an safe processing system.
According to the standards of Chinese food additive criteria, the maximum dose of use is 200 mg/kg in canned foods and plant protein foods, the maÿ@mum dose of use is 500 mg/kg in dairy products and meats, general dose is 100～200 mg/kg.
2. NISIN TECHNICAL DATA
Product Name: Nisin Chemical Formulation: C143H228O37N42S7
Approximate Formula Wt: 3348 INS: 234 CAS : 1414-45-5
Description: A Standardised powder of Nisin , which is isolated from a fermentation of a selected strain of Lactococcus lactic, the product is standardised by addition of sodium chloride .
Nisin is effective natural food preservative, can be used in products across a wide range of pH levels (3.5-8.0). Inhibition of spore-forming bacterica ( Particularly clostridium spore ) in selected dairy products and other food products. Application restricted by local legislation. Some of the application of Nisin are listed as following:
1.Dairy products: processed cheese and cheese spreads; direct acidified cheeses; pasteurised dairy desserts; fresh and recombined milk; cream product ( Flavoured , Whipped, Thickened, Sour cream etc ).
2. Canned foods
3. Plant protein foods
5. Beer & related product
6. Liquid egg product
7. Processed Fruits and Vegetables ( tomato products ( juices ) pH<4.5 );
8. Dressings and Sauces
9. High moisture/ reduced fat foods
10. Flour products ( Including noodle and pasta); flour product that are cooked on hot plates only e.g. Crumpets, Pikelets, Flapjacks etc.
11. Oil emulsions ( < 80% oil )
12. Mixed food ( Sauces and Toppings, including Mayonnaises and Salad dressings , Dips and Snacks, etc )
13. Processing of Fermentation products.
The specification of Nisin is listed as following Table 1:
Table 1. Specification of Nisin
Grey or off--white powder
pH of 10% water solution:
MAX 20 mg/kg
MAX 3 mg/kg
MIN 1000 IU/MG
5. Content of Nisin
6. Direction for use
It has been used in a wide variety of food products alone or in combination with other preservatives( e.g. Benzoic acid or Sorbic acid).Directly(or made into suspend solution first with boiled water) put it into food and stir well. General dose of use:100mg/kg-200mg/kg, Maximum dose:500mg/kg.
7. Packing : 500g or 1kg
Storage: Keep it tightly closed and stored in cool, dry and shady place.
Expiring date: Two years after packed during 4℃-15℃
The function of Nisin in Canned food for heat processing is listed as following Table 2.
Table 2. The function of Nisin in Canned food for heat processing
* Fo Value is the heat processing time (measured by minutes), keeping the temperature of 121℃in the centre of the food.
*Every gram food adds consistency of Nisin from 40～200 IU.
Nisin used baked foods
Baked foods, such as bread, cake and crumpets are high moisture,flour-based products that are produced by fermentation, baking, cooling and packing. Spoilage of baked food, mostly due to gas-producing bacteria and moulds, has been observed and attempts have been made to improve
shelf-life stability by modified atmosphere, packaging, storage temperature and the addition of sorbate. No attention has been given to the prevention of spoilage due to Bacillus spp. In fact, there have been a number of outbreaks of food poisoning due to this kind of bacteria in baked food. The addition of nisin in food processing may prevent food poisoning outbreaks.
Crumpets are particularly popular in the United Kingdom and Australia,and may be used as an example to demonstrate the advantages of nisin.
Crumpets have high moisture and high water activity. Consequently, they have a short shelf life of usually less than 6 days. The other reason leading to decreasing shelf life is that flour used in the manufacture of crumpets will invariably contain a low number of B. cereus spores. In the cooking process,
the bottom of the crumpets receives a high heat treatment, but the rest of crumpet receives a lower heat treatment, which Bacillus spores easily survive. Thus at the time of production crumpets will routinely contain a low level of B. cereus spores. During the 3 to 5 day shelf life of the product, the level of B. cereus may increase from undetectable levels to greater than 10 5 cfu/g, which can be sufficient to cause food poisoning. It was reported that nisin might be used as a preservative in crumpets. Different concentrations of nisin aqueous solution were added in batter to observe the effectiveness of preservative. The results showed that nisin has a strong inhibition effect of Bacillus cereus. Levels of use increased according to the increase of bacterial spores. When the residual nisin level in batter and crumpet was determined, the results demonstrated that the nisin is almost completely
20 degraded in the batter under room storage conditions, probably due to the high nisinase activity of contaminant organisms. The loss of nisin in crumpets was 69%. Because, during cooking, the bottom of a crumpet receives more intense heating than the top, the residual nisin level is different in different part of crumpets. Residual nisin level is lower in the bottom than the other parts. These results suggest that a moderately high level of nisin addition to batter is necessary to attain a concentration in excess of minimal inhibitory concentration in a freshly produced crumpet. Furthermore, similar studies have been carried out on wholemeal crumpets, pikelets and flapjacks with similar results. A high level of nisin of 625mg was found to be required in wholemeal crumpets whereas nisin levels of 375mg were found to be effective in both pikelets and flapjacks.
The higher level required in wholemeal crumpets is possibly due to more microbial spores in wholemeal flour.