Agency Response Letter GRAS Notice No. GRN 000159
CFSAN/Office of Food Additive Safety
May 27, 2005
George Burdock, Ph.D.
888 17th Avenue, N.W.
Washington, DC 20006
Re: GRAS Notice No. GRN 000159
Dear Dr. Burdock:
The Food and Drug Administration (FDA) is responding to the notice, dated October 5, 2004, that you submitted on behalf of Griffith Laboratories (Griffith, the notifier) in accordance with the agency's proposed regulation, proposed 21 CFR 170.36 (62 FR 18938; April 17, 1997; Substances Generally Recognized as Safe (GRAS); the GRAS proposal). FDA received the notice on October 8, 2004, filed it on October 14, 2004, and designated it as GRAS Notice No. GRN 000159.
The subject of the notice is Carnobacterium maltaromaticum strain CB1.(1) The notice informs FDA of the view of Griffith that C. maltaromaticum strain CB1 is GRAS, through scientific procedures, as an inhibitor of Listeria monocytogenes in ready-to-eat (RTE) meat products at a maximum concentration at inoculation of 1 X 104 colony forming units per gram (cfu/g).
As part of its notice, Griffith includes the report of a panel of individuals (Griffith's GRAS panel) who evaluated the data and information that are the basis for Griffith's GRAS determination. Griffith considers the members of its GRAS panel to be qualified by scientific training and experience to evaluate the safety of substances added to food. Griffith's GRAS panel discusses (1) the history and phylogeny of C. maltaromaticum; (2) its identity and characteristics, including antibiotic resistance profiles; (3) its natural occurrence in food, particularly in meat, fish, and cheese; (4) production and use of C. maltaromaticum cultures, including specifications, fermentation, and preservation procedures; (5) the growth characteristics of C. maltaromaticum on meat products; (6) estimates of exposure to and consumption of C. maltaromaticum in and on food; (7) the safety of ingesting amounts of the biogenic amine tyramine likely to be produced by C. maltaromaticum; and (8) that C. maltaromaticum is unlikely to be a human pathogen. Griffith's GRAS panel concludes that C. maltaromaticum would be safe when added to RTE meats at inoculation ranges between 103 and 104 cfu/g, resulting in the consumption of bacteria from these foods of up to 1.4 X 1011 cfu/day and that C. maltaromaticum would be generally recognized as safe for its intended use in RTE meats.
Griffith discusses publicly available information on the identity of C. maltaromaticum. Griffith describes C. maltaromaticum as naturally selected bacteria. Griffith discussed published information on the initial isolation, characterization, and taxonomic history of Lactobacillus pisciola (a prior designation for strains isolated from stressed rainbow trout that later were reclassified as C. maltaromaticum), lists properties that distinguish C. maltaromaticum from the genus Lactobacillus and other lactic acid bacteria, and discussed uses of lactic acid bacteria in fermented foods. C. maltaromaticum appears as Gram-positive, nonmotile, nonsporeforming rods that occur singly or in short chains and form pinpoint, convex, white, circular, nonpigmented colonies at 25 degrees C on Trypticase Soy Agar. It grows as a facultative anaerobe at temperatures from 6 to 40 degrees C, with optimum growth at 30 degrees C and pH ranging from 6.0 to 7.0. It requires folic acid, riboflavin, pantothenate, and niacin for growth, does not produce catalase or oxidase, and hydrolyzes arginine and esculin with variable gas production. Griffith notes that C. maltaromaticum strain CB1 is deposited as a proprietary strain with the American Type Culture Collection (ATCC) and provided data and information to affirm its identity. Griffith provides published and unpublished information on antibiotic resistance of C. maltaromaticum, comparing with and contrasting to human and dairy isolates of Lactobacillus as well as other Carnobacterium spp. Based on a literature search on antibiotic resistance in C. maltaromaticum, Griffith concludes that resistance to antibiotics in C. maltaromaticum would not be readily transferrable; e.g., plasmid-associated genes in C. maltaromaticum encode bacteriocin production, but have not been found to encode transferrable antibiotic resistance.
Griffith describes standard procedures for production of C. maltaromaticum strains and strain maintenance including growth of cultures in a production fermentor using food grade materials. Specifications include concentration of the C. maltaromaticum strain (between 3.2 X 106 and 3.2 X 107 cfu/g), residual moisture (less than 5 percent), and limitations on other microorganisms (non-lactic acid bacteria, yeasts, molds, and and Staphylococcus aureus at <100 cfu/g, anaerobic sporeforming bacteria and total coliforms at <10 cfu/g, and Clostridium botulinum, Escherichia coli, and Salmonella spp, absent in 50 g, 25 g and 1 g, respectively). Griffith will distribute packages that will yield between 103 and 104 cfu/g for the intended application.
Griffith intends to market C. maltaromaticum as an ingredient that will be sprayed onto the surfaces of RTE meat products at levels of up to 104 cfu/g to inhibit the growth of L. monocytogenes. Griffith indicates that C. maltaromaticum can grow on meat to a maximum concentration of 108 to 109 cfu/g. Using a per capita consumption of meat of 141 g/d, Griffith calculates that there would be a maximum per capita consumption of C. maltaromaticum of 1.41 X 1011 cfu/day; which Griffith suggests would not add significantly to bacterial flora in the body.
Griffith discusses published information documenting the presence of Carnobacterium spp. in food, including meat and meat products, vegetables, fruits, dairy products and seafoods at concentrations between 5 X 107 and 1 X 108 cfu/g. Several published reports support that Carnobacterium spp. were isolated from vacuum-packaged meat, fish, and cheese and that C. divergens and C. maltaromaticum naturally found in fermented meat products could exceed 106 cfu/g during the ripening period. High concentrations of C. maltaromaticum (5 X 105 to 8 X 108 cfu/g) were found in ripened French cheeses, such as Brie and Camembert. Griffith provided unpublished information that C. maltaromaticum inoculated on vacuum-packaged hot dogs grew to 2.75 X 106 cfu/g after 7 weeks of storage.
Griffith summarizes published and unpublished studies relevant to inhibition of the growth of L. monocytogenes mediated by bacteriocins. Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria, such as C. maltaromaticum. Bacteriocins are degraded by proteolytic enzymes; some bacteriocins are heat resistant. Resident intestinal microorganisms are not usually affected by bacteriocins. The bacteriocin produced by C. maltaromaticum was detected at day 10 through day 20 after inoculation. Griffith describes an unpublished experiment in which the activity of the bacteriocin from C. maltaromaticum CB1 was lost within 0.5 minutes after exposure to simulated gastric juice; concluding that the bacteriocin is readily digestible and thus, unlikely to be toxic or allergenic.
Griffith discusses published information on biogenic amines that may form in foods from amino acid decarboxylation by bacterial enzymes and describes histamine and tyramine as well-characterized biogenic amines believed to cause adverse effects in humans. Griffith notes that histamine can induce food poisoning symptoms similar to sombroid poisoning, but that C. maltaromaticum strains produce tyramine, but not histamine. Griffith summarized published and unpublished data on tyramine produced by growing Carnobacterium spp.; under laboratory conditions up to 140 microgram (µg)/gram/day of tyramine was detected, while on foods up to 262 µg/g was detected. Toxic threshold doses for tyramine are not precisely known; however, at least 200 milligram (mg) (equivalent to 2.86 mg/kg body weight) of tyramine was tolerated in healthy subjects, but at 200-400 mg, some individuals experienced increased systolic blood pressure. Griffith concluded that concentrations of tyramine in food inoculated with C. maltaromaticum would not result in adverse health effects.
Griffith also discusses published information about C. maltaromaticum infections in fish, which occur during spawning or handling, noting that stressed conditions predisposed fish to infection by Carnobacterium spp. and often were associated with other pathogenic bacteria. Ingested C. maltaromaticum have not been found pathogenic to fish. Griffith notes that human oral consumption of C. maltaromaticum has not been linked to adverse event reports and cite its characterization as "nonpathogenic" in Canada and France and its designation as Biosafety Level 1 (not known to cause disease in healthy adult humans) by ATCC. While Griffith summarized a published case report of C. maltaromaticum isolated from a human infection (in the stump of a hand accidentally amputated in a sawmill); Griffith deems this published report irrelevant to its intended use of C. maltaromaticum in meats.
Use in Meat Products
During its evaluation of GRN 000159, FDA consulted with the Labeling and Consumer Protection Staff of the Food Safety and Inspection Service (FSIS) of the United States Department of Agriculture (USDA). Under the Federal Meat Inspection Act, FSIS is responsible for determining the efficacy and suitability of food ingredients in meat products as well as prescribing safe conditions of use. Suitability relates to the effectiveness of the ingredient in performing the intended purpose of use and the assurance that the conditions of use will not result in an adulterated product, or one that misleads consumers.
FSIS does not object to the use of C. maltaromaticum strain CB1 under the proposed conditions of use to treat RTE comminuted meat products, such as hot dogs. All ingredients of the C. maltaromaticum spray solution will require ingredient labeling when used to treat meat products under the jurisdiction of FSIS. The proposed use of additional strains of C. maltaromaticum or the expanded use of C. maltaromaticum strain CB1 in other types of meat products or poultry will require an evaluation for suitability by FSIS. For these further uses, FSIS requested that FDA advise Griffith to seek regulatory guidance from FSIS, Labeling and Consumer Protection Staff, about the use of C. maltaromaticum in meat and poultry products. Griffith should direct such an inquiry to Dr. Robert Post, Director, Labeling and Consumer Protection Staff, Office of Policy, Program, and Employee Development, Food Safety and Inspection Service, 1400 Independence Ave., S.W., Suite 602, Annex, Washington, DC 20250-3700. The telephone number for that office is (202) 205-0279 and the telefax number is (202) 205-3625.
Based on the information provided by Griffith, as well as other information available to FDA, the agency has no questions at this time regarding Griffith's conclusion that C. maltaromaticum strain CB1 is GRAS as an inhibitor of L. monocytogenes in RTE meat products under conditions set by USDA/FSIS. The agency has not, however, made its own determination regarding the GRAS status of the subject use of C. maltaromaticum. As always, it is the continuing responsibility of Griffith to ensure that food ingredients that the firm markets are safe, and are otherwise in compliance with all applicable legal and regulatory requirements.
In accordance with proposed 21 CFR 170.36(f), a copy of the text of this letter, as well as a copy of the information in your notice that conforms to the information in proposed 21 CFR 170.36(c)(1), is available for public review and copying on the homepage of the Office of Food Additive Safety (on the Internet at http://www.cfsan.fda.gov/~lrd/foodadd.html).
Laura M. Tarantino, Ph.D.
Office of Food Additive Safety
Center for Food Safety
and Applied Nutrition
cc: Dr. Robert Post, Director
Labeling and Consumer Protection Staff
Office of Policy, Program and Employee Development
Food Safety and Inspection Service
1400 Independence Ave., SW, Suite 602, Annex
Washington, DC 20250-3700
(1)The notice, dated October 8, 2004, listed seven C. maltaromaticum strains for use in ready-to-eat and fresh comminuted meat products. An amendment, dated January 27, 2005, limited the use to ready-to-eat meat products to conform with USDA regulations. An amendment, dated April 8, 2005, limited the subject of the notice to C. maltaromaticum strain CB1 and provided information on the identity of this strain.