How do I make shrubs or fermented fruit preserves, and where do they fall under the rules?

A shrub, or drinking vinegar, is fruit macerated in sugar until it gives up a syrup, strained, and mixed with vinegar, usually in roughly equal parts of fruit, sugar and vinegar. It is made without cooking, kept in the refrigerator, and lasts for months there. Fermented fruit preserves, made by letting yeasts or bacteria work on fruit and sugar, are a different product with no tested home method in US guidance, so treat them as refrigerator foods. Under federal rules, refrigerated foods are excluded from the acidified food regulation, but selling either product depends on your state. This page covers the methods, the storage and the rules.

Three products that get lumped together

The third column belongs here only because people search for "fermented jam" when a batch starts bubbling. A canned jam that ferments has failed. It has nothing in common with a shrub or a deliberate ferment.

Making a shrub

UC Master Food Preservers in El Dorado County teach shrubs from Michael Dietsch's book Shrubs, and their handouts give the working ratios [1][2].

The ratios

• 1:1:1 fruit, sugar and vinegar, in equal parts, is the common starting formula [1].
• 2:1:1 (two parts fruit to one part sugar and one part vinegar) is the other basic ratio [1].
• The handouts say there is no set rule and you can follow your taste [1]. Change the sugar and vinegar to taste, but keep the vinegar acidity and the refrigeration below, because those are what keep a shrub safe.

The cold process, step by step

1. Prepare the fruit. Wash fruit and herbs, discard anything moldy, and use unwaxed citrus or remove the wax before zesting [2].
2. Macerate. Combine chopped or crushed fruit with sugar and let it stand about 24 hours until it forms a syrup [1]. Several of the handout recipes do this step in the refrigerator, covered, for one to two days [1][2].
3. Strain off the solids [1].
4. Add vinegar. Combine the syrup with vinegar. Choose a vinegar of at least 5 percent acidity if you do any of the infusing outside the refrigerator. Rice vinegar is usually below 5 percent, so a shrub made with it should be infused in the refrigerator [2]. Plain white distilled vinegar tastes harsh in a shrub; cider, wine, sherry and balsamic vinegars are the usual choices [1].
5. Rest and store. Most of the handout recipes have you wait about a week in the refrigerator before using the shrub, so the sugar and vinegar round out [1][2].
6. Serve a spoonful or two in sparkling water, or in a cocktail.

Sterilizing the bottles first may help prevent contamination and extend shelf life. The handouts give the same method as for canning jars: boil them 10 minutes at 1,000 feet or less, adding 1 minute for each additional 1,000 feet [1][2].

Sugar choices

White or raw cane sugar gives the clearest, most neutral shrub. Honey is sweeter than sugar and can make shrubs cloudy, so use less; maple sugar is about twice as sweet as white sugar [2].

How long a shrub keeps, and when to throw it out

Shrubs should be stored in the refrigerator, where they keep for up to a year [1]. An Oregon State extension responder, answering a home cook's question about cold-process fruit syrups and shrubs, said refrigerated storage is not a safety issue because of the sugar and the fruit's acidity, with the vinegar adding more, and that freezing is safe and keeps the flavor fresher than refrigeration [3].

Throw a shrub away if you see mold, or if it starts to look bubbly, cloudy or slimy [1]. When in doubt, throw it out [2].

Fermented fruit preserves

Fruit can be fermented in several ways: whole fruit in a honey ferment, fruit with a small amount of salt and a starter culture, fruit kvass, or fruit left with sugar until wild yeasts begin to work. These are traditional foods and many people make them. None of the US home preservation sources reviewed for this page (USDA, NCHFP and the university extension services) publishes a tested method for a fermented fruit preserve.

That leaves you with untested products. If you make them:

• Keep them in the refrigerator from the time fermentation is finished, and treat any batch with mold, a slimy texture or an off smell as spoiled.
• Do not can them, and do not seal them airtight at room temperature to "finish." Fermenting fruit makes gas, and the result can be a pressurized jar.
• Do not add low-acid ingredients (onion, garlic, peppers, herbs in oil) to a fruit ferment. A ferment that fails to sour leaves those ingredients without protection.
• Give no shelf life on a label you cannot back with a test.

Where these sit under the acidified food rule

Federal acidified food rules (21 CFR Part 114) are what require process filing and a process authority for products such as pickles; whether they reach pepper jelly is an open question, covered on pepper jelly. For a shrub or a ferment, the answer turns on the definitions:

• Acid foods are foods with a natural pH of 4.6 or below [4]. Most fruits are acid foods, and a shrub made from them with vinegar stays one.
• Acidified foods are low-acid foods to which acid or acid foods are added, with a water activity above 0.85 and a finished equilibrium pH of 4.6 or below [4]. Peppers and tropical fruits are named among the examples [4].
• Foods that are stored, distributed and retailed under refrigeration are excluded from Part 114 [4]. A shrub or ferment kept refrigerated all the way to the buyer is outside the federal acidified rule.
• Fermentation is not mentioned in section 114.3. The definition turns on acid being added. Michigan's agriculture department states that fermented foods are exempt from its low-acid and acidified food requirements and tells producers to contact their area inspector [5]. That is one state's reading; do not assume another state or FDA reads it the same way.

So a fruit shrub made only from fruit, sugar and vinegar is generally an acid food. A shrub that adds a low-acid ingredient, such as cucumber, peppers or a large amount of fresh herbs, moves toward the acidified definition if it is sold at room temperature, and the honest way to know is a pH test and a process authority's review. The pH page explains the 4.6 line and how to measure it, and process authorities and scheduled processes explains what a review involves.

Selling shrubs and fermented fruit

State rules, more than federal ones, decide this. Cottage food lists are written around shelf-stable foods, and many of them leave out refrigerated products, beverages, acidified foods and ferments. Three examples, checked in October 2026: Michigan's cottage food rules do not allow fermented foods or beverages [6]; Idaho's 2026 food freedom act lists fermented food products among its shelf-stable examples, although the state's older cottage food rule excluded them [7]; and Montana's Local Food Choice Act does not exclude acidified or fermented foods [8]. Rules change, so confirm with the agency named for your state.

Before you sell:

1. Find out whether your state's home food route allows beverages, refrigerated foods, acidified foods or fermented foods at all. Preserves cottage food laws often exclude lists the usual exclusions.
2. If the product leaves your kitchen refrigerated, plan for keeping it cold at the market and in transit, and label it "Keep refrigerated."
3. If it contains any low-acid ingredient, get a pH reading from a lab or process authority before you decide what it is.
4. Ask your agency in writing if your product does not fit their list neatly. Shrubs are new to many inspectors.

The safety picture for jam itself

Shrubs and ferments raise questions about acid, sugar and botulism that apply to jam too. Why ordinary fruit jam is on the safe side of that line, and where the real risks enter, is on can jam give you botulism?

References

1. UC Cooperative Extension, Master Food Preservers of El Dorado County, Kombucha and Shrubs (recipes from Dietsch, Shrubs, 2nd ed.), September 23, 2023. https://www.ccfruitandnuts.ucanr.edu/sites/default/files/2023-10/389540.pdf
2. UC Cooperative Extension, Master Food Preservers of El Dorado County, shrubs handout (adapted from Dietsch, Shrubs, and Han, Wild Drinks and Cocktails), November 16, 2019. https://ucanr.edu/sites/mfp_of_cs/files/315888.pdf
3. Ask Extension, Oehler, Keeping cold process fruit syrups or fruit shrubs (question 847711, Lane County, Oregon), August 29, 2023. https://ask.extension.org/kb/faq.php?id=847711
4. Code of Federal Regulations, 21 CFR 114.3, Definitions (Cornell LII), current. https://www.law.cornell.edu/cfr/text/21/114.3
5. Michigan Department of Agriculture and Rural Development, Low acid foods and acidified foods, undated (viewed October 2026). https://www.michigan.gov/mdard/food-dairy/wholesale-industry-resources/wholesale-manufactured-foods-new-business-guide/food-operations-with-special-requirements/low-acid-foods-and-acidified-foods
6. Michigan Department of Agriculture and Rural Development, What Can I Make? (cottage food), undated (viewed October 2026). https://www.michigan.gov/mdard/food-dairy/cottage-food/what-can-i-make
7. Idaho Legislature, S.B. 1283 (2026) bill text. https://legislature.idaho.gov/wp-content/uploads/sessioninfo/2026/legislation/S1283.pdf
8. Montana Department of Public Health and Human Services, Montana Local Food Choice Act Guidance, October 1, 2023. https://dphhs.mt.gov/assets/publichealth/FCS/CottageFood/MLFCAGuidanceDoc-FAQ10.1.23.pdf