Vegetable meat cure

Some chefs and retailers are turning to “natural” sources of nitrate or nitrite when curing meats.  The most common reason is to retain a claim of “natural” or preservative-free. Traditional nitrite or nitrate salt mixtures (pink salts) are food additives and preservatives that were chemically synthesized.

Some vegetable extracts such as celery juice powder contain naturally occurring nitrites and nitrates. In its natural form the vegetable extracts are mostly nitrate. Some manufacturers may culture (ferment or enzymatically convert) the nitrate into nitrite. A careful analysis of the product label is required.

When used correctly, a vegetable extract can provide the same culinary objectives as synthetic sodium nitrite/nitrate. There are no USDA standardized limits, procedures, or contact times for vegetable based nitrates or nitrites.

USDA FSIS | Are celery powder and other natural sources of nitrite approved for use as curing agents?
No, neither celery powder (whether in a pre-reduced form or with a bacterial nitrate-reducing culture) nor other natural sources of nitrite are approved for use in 9 CFR 424.21(c) as curing agents. Therefore, products that are formulated with celery powder or other natural sources of nitrite instead of curing agents in 9 CFR 424.21(c) (e.g., hot dogs and corned beef that contain celery powder instead of sodium or potassium nitrite) must be labeled as “uncured” under 9 CFR 319.2. In addition, the label must also contain the statement “no nitrates or nitrites added” per 9 CFR 317.17 that is qualified by the statement “except for those naturally occurring in [name of natural source of nitrite such as celery powder]” in order to not be considered false and misleading under 9 CFR 317.8.

 How would the use of vegetable-based powders containing nitrate or nitrate be addressed in the food code?  Looking at the ask FSIS answer above the USDA has stated:

  • they are NOT approved for use as [antimicrobial] curing agents
  • they ARE considered flavoring agents
  • labeled (retail) items would be expected to be labeled “uncured; no nitrates or nitrites added except for those naturally occurring in [name of natural source of nitrite such as celery powder]”
Therefore, it is reasonable to conclude that curing meats with vegetable-based powders under the US FDA model Food Code would be permitted for flavoring and texture.  These meat products would need to be held outside the temperature danger zone during production.

 Can an operator under the US FDA model Food Code obtain a variance for use of these products to cure meats for safety? 

Curing agents provide more than color retention; they are also important in the control of growth of Clostridium perfringens as well as Clostridium botulinum and its toxin formation in cured products.  Available research from 2011 had not yet supported that naturally occurring sources of nitrite alone can sufficiently control the growth of these pathogens when compared to products that are conventionally cured with sodium nitrite.  However, in 2016 the USDA cited: “FSIS has determined from expert elicitation that nitrite from natural sources should also control the growth of C. botulinum provided ascorbate or a cure accelerator such as erythrobate is added (askFSIS, 2016)”.

 Under Canadian Meat regulations, curing meats with cultured celery powder is permitted.  

2016. Annex C. Section 2.1 Preformed nitrites: Cultured celery powder (or other cultured vegetable juice powders approved for this purpose) may be used as an alternative source of nitrites in the production of cured or fermented meat products. Cultured celery powder contains preformed nitrites produced by bacterial action on nitrates present in the celery product. The level of preformed nitrites present in the celery powder must be declared by the manufacturer of the cultured celery powder. The producer of the meat product must determine the amount of cultured celery powder to be included in the formulation to achieve the minimum levels of nitrites needed to cure the product without exceeding the maximum allowable limit.

A Food Code variance would likely require lab findings for residual nitrite for verification of cure effectiveness. The same should hold true for nitrite or nitrate usage limits. Unlike standardized curing salts mixtures, there are no standards of nitrite or nitrate content in a celery juice powder. The recommendation would be to choose a vendor for the celery juice powder that can provide a certificate of analysis (CoA) stating the exact content of nitrite and nitrate. They should also provide a suggested usage level based on that CoA. For example, one manufacturer states that an operator should use 1.25 oz. of its powder in 25 pounds of ground meat.  After usage, send samples to a lab to verify that there are residual nitrite levels sufficient to prevent the outgrowth of C. botulinum.