Does fermenting change the rules for my sauce?

Sometimes, and you do not get to decide it alone. FDA's 2010 draft guidance, later withdrawn in part, said that "Not all fermented foods meet the definition of 'acidified foods'" but "some fermented foods that contain acid are also acidified foods" [1][6]. This book takes a firm line on the common case: a pepper ferment finished with vinegar, citrus juice or any other added acid is treated as an acidified food that needs a scheduled process, unless a process authority classifies it otherwise in writing. A ferment that reaches pH 4.6 or below on its own, with nothing acidic added, may fall outside the federal rule. Who makes that call, and what your state says, is what this page sorts out.

What FDA has actually said

The federal definition in 21 CFR 114.3(b) covers "low-acid foods to which acid(s) or acid food(s) are added" and reach a finished equilibrium pH of 4.6 or below [2]. The section never mentions fermentation. Fermentation lowers pH through lactic acid made by bacteria in the jar, which is acid produced in the food rather than acid added to it. That difference is why FDA's guidance and many state rules discuss fermented foods separately.

FDA addressed it in the notice announcing its draft acidified foods guidance (75 FR 59268, September 27, 2010) [1]. The key lines:

• "Not all fermented foods meet the definition of 'acidified foods' in 21 CFR 114.3(b)."
• "However, some fermented foods that contain acid are also acidified foods."
• Processors of acid foods and fermented foods that are not acidified foods "would not be subject to the acidified food regulations."
• Those processors "may choose to voluntarily register and file scheduled processes" with FDA.

Two limits on that text matter. First, it was only ever a draft. FDA's notice says the guidance "does not create or confer any rights for or on any person and does not operate to bind FDA or the public" [1]. FDA never finalized it, and on December 30, 2015 it withdrew the draft guidance in part (80 FR 81550) [6]. The 2010 text is still the most direct thing FDA has published on ferments, and it binds no one. Second, the notice does not give a test for which fermented foods count. It names sauerkraut, cucumber pickles and green olives as fermented low-acid foods, and leaves hot sauce unmentioned [1].

Three kinds of fermented sauce

Most fermented hot sauces fall into one of three patterns. The third column is how this book treats each one. It is a starting position for your conversation with a process authority, and it rules on nothing.

The third row is the one Georgia's bulletin spells out. UGA defines fermented foods as low-acid foods fermented by acid-producing microorganisms until pH reaches 4.6 or below, and notes that partially fermented foods "need added acid" to get there, which makes them acidified [3]. Cold-pack pickles that need added acid are classed as acidified in the same document [3].

Some regulators lean further toward exemption than this book does. Minnesota's Department of Agriculture says fermented foods whose pH drops through natural fermentation, rather than added acid, are exempt, giving traditional sauerkraut and kimchi as examples [4]. Montana's overview says: "If the final pH of all parts of the fermented food is 4.6 or less, the food would not be an acidified food" [5]. Those are each state's reading for its own licensing, and neither changes the federal text. Neither source addresses a sauce with vinegar added after fermentation. That is the gap this book closes conservatively: once acid goes in, treat it as acidified until a process authority says otherwise.

Other food rules still apply to a ferment outside Part 114. Eurofins notes that fermented products that may be exempt from Part 114 are still covered by 21 CFR 117, the current good manufacturing practice rule [7]. Food facility registration, labeling and state licensing still apply.

Why the vinegar question matters so much

Most fermented hot sauces get vinegar at the end, for flavor, for a lower and steadier pH, and because a ferment blended with nothing acidic keeps fermenting in the bottle. Finishing a ferment covers the methods. From a regulatory view, adding the vinegar is the step that makes a fermented pepper mash fit the words of 114.3(b): "low-acid foods to which acid(s) or acid food(s) are added" [2].

A fermented sauce also carries the same pathogen question as any acidified sauce. Holding pH at or below 4.6 stops botulism, but acid-tolerant organisms like E. coli O157:H7 need a heat step or a long enough hold at low pH to die off [8]. The published hold data for unheated sauces applies to acetic acid sauces below pH 3.3, and a process authority has to set any cold-fill process for sale; cold fill has the numbers.

Process authorities that will not take ferments

Not every process authority will evaluate a fermented product. Washington State University's Food Processing Extension states plainly: "We do not provide process authority evaluations for any fermented products." It also declines products that have not been thermally processed [9]. Other university authorities do not say either way on their public pages; Cornell's and Texas A&M's fee and submission pages, as of October 2026, do not mention fermented products [10][11]. Ask before you pay.

When you contact an authority about a ferment, send:

1. The full formula by weight, including salt as a percentage of the peppers and other produce.
2. Fermentation time and temperature, and pH readings across the ferment with dates.
3. Whether, when and how much acid you add after fermenting.
4. Whether you heat the sauce after blending, to what temperature and for how long.
5. Container, closure and how the sauce will be stored and sold.

Ask for a written classification letter that states whether the product is an acidified food. If the answer is that it is not, keep that letter with your records. If FDA disagrees, the 2010 draft notice said it would tell you so and expect you to follow the regulation [1].

How states list fermented foods

State cottage food and home food laws often list fermented foods separately from acidified foods, and they do not agree. Some allow fermented foods from home kitchens, some allow them with conditions such as a pH test, and some exclude them outright. Examples from the agencies' own pages:

Oregon shows how informal this can get. An Oregon State University Extension answer from February 1, 2023 told a grower that fully fermenting peppers and blending them into a sauce "is okay under farm-direct," and that "you're required to test each batch of acidified product for pH before selling" [17]. A May 29, 2026 OSU Extension article adds only that "a fermented hot sauce with no added vinegar or acid may follow a different review process" [18]. Both point you back to the Oregon Department of Agriculture. Your state page under selling hot sauce in your state gives the current rule and agency.

What to do with your ferment now

1. Decide whether your finished sauce has any added acid. If it does, plan on the full acidified food path.
2. If it does not, find a process authority that evaluates ferments and ask for a written classification.
3. Call your state agriculture or health department and ask how it treats fermented hot sauce by name as well as fermented vegetables in general.
4. Keep every pH reading from every batch. Whether you are exempt or not, records are what you show an inspector.

Never tell a buyer or an inspector your sauce is exempt because it is fermented. Say who classified it and show the letter.

Finding someone who will classify your ferment

The next step is a process authority who accepts fermented products and will put the classification in writing. Finding a process authority covers how to choose one and what they need from you.

References

1. U.S. Food and Drug Administration, Draft Guidance for Industry: Acidified Foods; Availability, 75 FR 59268, Docket FDA-2010-D-0434, September 27, 2010. https://regulations.justia.com/regulations/fedreg/2010/09/27/2010-24089.html
2. Legal Information Institute, Cornell Law School, 21 CFR 114.3 Definitions, accessed October 2026. https://www.law.cornell.edu/cfr/text/21/114.3
3. Mohan, A., Step-by-Step Guidelines for Processing, Manufacturing, and Regulatory Approval of Acidified Foods in Georgia, UGA Extension Bulletin B 1455, November 2015. https://secure.caes.uga.edu/extension/publications/files/pdf/B%201455_1.PDF
4. Minnesota Department of Agriculture, Acidified Foods, modified July 30, 2025. https://www.mda.state.mn.us/acidified-foods
5. Montana Department of Public Health and Human Services, Acidified Food Overview, revised December 11, 2014. https://www.dphhs.mt.gov/assets/publichealth/FCS/Wholesale/AcidifiedOverview.pdf
6. U.S. Food and Drug Administration, Acidified Foods; Draft Guidance for Industry; Withdrawal of Draft Guidance (in part), 80 FR 81550, December 30, 2015. https://www.govinfo.gov/content/pkg/FR-2015-12-30/html/2015-32781.htm
7. Eurofins, Process Authority: FAQ and Answers, May 8, 2025, updated May 6, 2026. https://www.eurofins.com/en-us/food-feed-testing/resource-library/process-authority-faq-and-answers/
8. Breidt, F., Sandeep, K. P., and Arritt, F. M., Use of Linear Models for Thermal Processing of Acidified Foods, Food Protection Trends 30(5):268-272, 2010. https://site.extension.uga.edu/foodscienceandtechnology/files/2023/07/Breidt-et-al-2010-Below-4.1.pdf
9. Washington State University Food Processing Extension, Product Evaluation, accessed October 2026. https://foodprocessing.wsu.edu/extension/product-eval/
10. Cornell Food Venture Center, CFVC Services and Fees, accessed October 2026. https://cals.cornell.edu/cornell-agritech/partners-institutes/cornell-food-venture-center/cfvc-services-fees
11. Texas A&M AgriLife Extension, Food Processing Entrepreneurs: Submitting Samples, accessed October 2026. https://aggie-horticulture.tamu.edu/food-technology/food-processing-entrepreneurs/getting-started/submitting-samples/
12. Penn State Extension, Who to Contact if You Want to Sell Home Preserved Foods, March 17, 2025. https://extension.psu.edu/who-to-contact-if-you-want-to-sell-home-preserved-foods
13. Illinois General Assembly, Public Act 103-0903, effective January 1, 2025. https://ilga.gov/Legislation/publicacts/view/103-0903
14. Wisconsin Department of Agriculture, Trade and Consumer Protection, Selling Home-Canned Foods, undated, accessed October 2026. https://datcp.wi.gov/Pages/Programs_Services/FSHomeCannedFoods.aspx
15. Michigan Department of Agriculture and Rural Development, Cottage Food: What Can I Make?, accessed October 2026. https://www.michigan.gov/mdard/food-dairy/cottage-food/what-can-i-make
16. South Carolina Department of Agriculture, Home-based Food Production Law guidance, July 2025. https://agriculture.sc.gov/wp-content/uploads/2025/07/SCHome-basedFoodProductionLawBook2025_digital.pdf
17. Oregon State University Extension (Clackamas County), Ask Extension answer on fermented pepper hot sauce under farm-direct, February 1, 2023. https://ask.extension.org/kb/faq.php?id=819582
18. Hibbard-Swanson, J., How do I start selling homemade hot sauce in Oregon?, Oregon State University Extension, May 29, 2026. https://extension.oregonstate.edu/ask-extension/featured/how-do-i-start-selling-homemade-hot-sauce-oregon