What Is Nisin?

The bacteriocin nisin is a natural antimicrobial agent with activity against a wide variety of undesirable food borne (pathogenic) bacteria. It is a peptide which is produced by the food grade dairy starter bacterium Lactococcus lactis. Nisin is used as a preservative in heat processed and low pH foods. Nisin cannot be synthesised chemically, so the nisin-producing L. lactis bacteria are used for the synthesis of nisin. A nisin preparation is applied as a concentrate of dry material derived from the controlled fermentation of L. lactis.

 

Structure of Biopreservation with Nisin

. Purposes of the Usage

 

The purposes of application of nisin in foods are multifold:

1) Extend shelf life

2). Cost saving for food processors

    • Reduce the temperature of the heat processing

    • Shorten the time of the heat processing.

    • Protect against temperature abuse of chilled products during storage and distribution.

    • In certain cases use ambient instead of chilled condition for storage and distribution.

3). Ensure Food Safety

Nisin is effective in controlling of pathogenic/food poisoning organisms such as Listeria, Bacillus cereus and Clostridium botulinum as part of an overall safe processing system.

4). Improve Food Quality

Usage Directions and Recommendations

 U.S. FDA’s Gras notice indicated that for use on casings for frankfurters and on cooked meat and poultry products as an antimicrobial agent. Nisin would be used

 

Food Applications *  Nisin Level */ usage level of Niprosin ®
(mg/Kg or mg/L) 

Processed cheese

5-15/200-600

Ricotta cheese

2.5-5.0/100-200

Dipping sauces

1.25-6.25/50-250

Pasteurized milk products

0.25-10.0/10-400 

Crumpets

4-6.25/150-250 

Continental type cooked sausage

5-25/200-1000

Salad dressing

1.25-6.25/50-250

Bear

25-37/1000-1500

Bear, post fermentation

0.25-1.25/10-50

Pasteurized chilled soups

0.25-6.25/10-200 

Canned foods (high acids)

2.5-5/100-200

*:  Delves-Broughton, J. (2005) Nisin as a food preservative. Food Australia, 57(12):525-527.

Known Regulations

 

Nisin is currently recognized as a safe food preservative in approximately 50 countries.

 Nisin is the only lantibiotic allowed as a food supplement. In 1969 the FAO/WHO Expert Committee on Food Additives stated nisin to be safe and natural food additive (FAO/WHO, 1969).

 Some fifteen years later nisin was commercially used in at least 39 countries (Hurst, 1983). In 1983 nisin was incorporated to the EEC food additive list and given the designation E234 (EEC, 1983). In the US, the Food and Drug Agency gave nisin a GRAS status (Generally Regarded As Safe) in 1988 (Federal Register, 1988). By the year 1996 nisin was allowed as a food additive in more than 50 countries, including the EU, China, and the US (Delves-Broughton et al., 1996).

 The concerned part on nisin from U.S. CFR - Code of Federal Regulations Title 21, is incorporated here:  PART 184, Subpart B, Sec. 184.1538 Nisin preparation.

 (a) Nisin preparation is derived from pure culture fermentations of certain strains of Streptococcus lactis Lancefield Group N. Nisin preparation contains nisin (CAS Reg. No. 1414-45-5), a group of related peptides with antibiotic activity.   

(b) The ingredient is a concentrate or dry material that meets the specifications :   

–(1) Nisin content, not less than 900 international units per milligram.  

–(2) Arsenic, not more than 1 part per million.   

–(3) Lead, not more than 2 parts per million.   

–(4) Zinc, not more than 25 parts per million.   

–(5) Copper, zinc plus copper not more than 50 parts per million.  

–(6) Total plate count, not more than 10 per gram.   

–(7) Escherichia coli, absent in 10 grams.  

–(8) Salmonella, absent in 10 grams.   

–(9) Coagulase positive staphylococci, absent in 10 grams.