Lacto-fermentation relies on lactic acid bacteria converting sugars into acid. Salt, ingredient proportions and fermentation conditions help guide that process. Use a tested recipe from a food-preservation authority, such as NCHFP fermented dill pickles or NCHFP sauerkraut, and follow the entire procedure.
What is lacto-fermentation?
The name refers to lactic acid, not dairy. Vegetables can carry bacteria that produce acid during fermentation. Salt favours desired organisms, but a salt ratio alone does not establish safety. Temperature, ingredient proportions, submersion, acid development and storage all matter.
Fermentation and vinegar pickling use different preservation processes. Some tested fermented-pickle recipes also contain a little vinegar at the start. Preserve all the quantities in the selected recipe instead of removing vinegar or inventing a new brine.
Match the percentage to its weight basis
A percentage only makes sense when you know which ingredients it includes. Here are three arithmetic examples, not recommended recipes:
For vegetables plus water, include all prepared vegetables, recipe add-ins and the water actually used in the batch. Exclude the jar, weights and salt. Use all of the measured ingredients and salt; discarding some mixed brine changes the amount of salt remaining.
For water only, calculate the salt for the prepared brine before it contacts the vegetables. The recipe still needs to specify the food quantity and process. This is not a measurement of the final salt concentration after moisture and salt move between vegetables and brine.
For dry salting, calculate against the prepared vegetables. If more covering brine is needed, follow the recipe’s separate instructions. Whether you pour brine over vegetables does not by itself tell you which percentage basis the recipe uses.
These recipe ratios exclude salt from the base weight. They differ from a true mass percentage of the finished salted mixture.
Choose a recipe for your produce
Different foods and preparation methods need different procedures. Start with a tested recipe for the produce you plan to preserve. The NCHFP dill pickle recipe specifies cucumber, water, salt and vinegar quantities together; its sauerkraut recipe uses a dry-salting procedure. Neither is a universal recipe for mixed vegetables, hot sauce, olives or every other ferment.
Use fresh produce and follow the recipe’s washing, trimming and cutting instructions. Do not change the vegetable-to-water ratio while keeping the same salt amount.
Keep vegetables submerged
Use the recipe’s food-safe container and weighting method to hold the produce under brine. Follow its headspace, covering and handling instructions. If extra brine is needed, use the recipe’s stated covering-brine formula; do not assume it is the same percentage as a vegetables-plus-water calculation.
Related calculator
Fermentation Brine Calculator
Calculate salt using vegetables plus water, water only, or dry vegetable weight. Match the percentage and basis in your tested recipe.
Follow the temperature and time instructions
Use the temperature range and fermentation procedure specified by your recipe. Changing the salt or temperature to make fermentation faster can change the process. There is no universal number of days or taste threshold that establishes completion for all vegetables.
Free Fermentation Salt Reference Card (printable PDF)
A printable PDF companion for the brine & pickling calculators and guides.
Manage fermentation gas
Fermentation can produce carbon dioxide. Use the vessel and covering method recommended by the recipe, and follow the equipment manufacturer’s instructions for pressure release. Do not seal an actively fermenting batch in a vessel without a way for gas to escape.
Observe the batch without assuming safety
Bubbles, cloudiness and a sour aroma can occur during fermentation. They do not prove that the food is safe or ready for storage. Follow the recipe’s checks and completion criteria, including any specified acidity measurements.
Follow spoilage guidance
Do not taste a suspect batch. Follow the recipe’s instructions for surface growth and spoilage. The NCHFP fermented dill pickle recipe directs readers to discard pickles that become soft, slimy or develop a disagreeable odour. Do not assume a growth is harmless from colour alone or use smell to certify a batch as safe.
Store the finished ferment as directed
Follow the tested recipe’s refrigeration or canning instructions after fermentation. A fermented jar is not automatically shelf-stable. For canning, use the full tested procedure and altitude adjustments. Do not dilute an active ferment to reduce salt or shorten the process to compensate for a low salt amount.
NCHFP recommends canning or pickling salt. Its salt guidance permits iodized and non-iodized table salt, notes that anti-caking ingredients can cloud brine, and advises against reduced-sodium salt for fermented pickle recipes.
Read NCHFP’s fermentation guidance, Illinois Extension’s dry-salting and brining guidance, and Minnesota Extension’s fermentation guidance for the full context.
