Brine Calculator

Saltwater is the simplest solution in the kitchen but also the most obscure part of many recipes. Although salt content is given as a percentage, few people explain what that percentage refers to.

Because of this lack of information, the salt content of sauerkraut in one book (e.g. 2%) can differ by a third from another book (e.g. 2%). There are methods that only take into account water and others that include both the cabbage and the water.

This calculator allows you to change the denominator from a predefined base to a controllable selection. By selecting the reference value for the percentage it shows how much salt is required, what concentration can actually be achieved or the ratio of water to salt and also explains what happens chemically in the solution.

What does the percentage of salt water mean?

The percentage of salt water is a mass ratio. Salt is always measured by weight. The only question is what value to use as the denominator.

Water is convenient. Since water has a density of 1 gram per milliliter, one liter of water equals one kilogram, and a 3% salt solution would be equal to one kilogram of water plus 30 grams of salt. Because of this simple calculation, the method using only water as a reference point is the standard method used in many books on fermentation.

It makes more sense to take the ingredients and water as a base. Most vegetables are made up of water, so if you put them in a jar and leave it for a day, that water is already brine. The fact that this has been taken into account from the start is why some restaurants can make a variety of fermented foods with the same ratio.

A concrete example:

Let's say you want to make a salt solution with a volume of 2.5 liters and a concentration of 2% using water as the base. Most fermentation recipes are designed to use this method of calculation.

Fifty grams: if you take the total weight as a basis, for example in a glass of chopped greens with a weight of 900 g and water with a weight of 1600 g, then the basis is the sum of 2500 g, and the result would also be 50 g. This accidental coincidence is why the two methods can easily be confused.

If you mix 1 kg of cucumber with 1 liter of water and calculate it as 3.5%, then using water as the basis would require 35 g of salt while using total weight as the basis would require 70 g. The latter would have a taste reminiscent of sea water.

A hidden pitfall in percentage statements that no one explains.

A salt solution with water as the solvent (10%) has a different concentration of salt than 10%. If you add 200 grams of salt to 2000 grams of water, then the weight of the resulting liquid is 2200 grams, and the proportion of salt in it will be 9.09%.

The difference is small at concentrations used for fermentation but becomes larger at higher concentrations used for preservation. At 2%, there are two possible interpretations differing by a quarter of a percentage point while at 25% the difference is exactly five percentage points.

Chemically speaking, it is important to pay attention to the second number as this indicates the actual concentration of the solution. Recipes almost always refer to the first number. This calculator shows both values simultaneously so you don't have to guess which convention a particular source uses.

The amount of salt required per ingredient:

These are concentrations that have been established over time in the traditions of fermentation and preservation. Unless otherwise stated all values refer to water as a solvent. Do not consider these values as rigid rules but rather averages within a certain range.

Wet salting, dry salting, equilibrium salting.

For brining in a saturated solution, high concentration of the solution and precise time control are required. When meat is immersed into a salt solution with 5 to 7% concentration, it quickly absorbs salt on its outside surface so that it must be removed before the surface becomes too salty. As the salt will be distributed inside when cooked later, the finished poultry has uniform taste even if the brine does not reach the center.

Dry brining does not use water. The salt on the surface pulls moisture out of the meat and dissolves to be reabsorbed by the meat itself as a concentrated saline solution. This prevents dilution, and causes the skin to dry out, which is why poultry is well suited for dry brining.

The equilibrium brining is a more patient method. The meat and water are weighed together, and a small amount of salt is added. The salt then naturally distributes itself until all areas have the same concentration. At this point no further change will take place. This makes it more flexible as poultry won't become too salty even if stored for longer periods.

Not all salt is equal.

Recipes that call for measuring salt with a spoon are not only measuring the salt but also air. The amount that fits in a spoon depends on the shape of the crystals and there can be differences between brands that exceed twice as much.

Replacing a tablespoon of table salt with a tablespoon of Diamond Crystal will nearly double the amount of salt. This is one of the most common causes for home-canning failures, which is why reliable canning resources strongly recommend purchasing a scale.

Do not use iodized salts or salts with anti-caking agents during active fermentation. Iodine acts as an antibacterial agent, and this is undesirable when culturing lactic acid bacteria. Anti-caking agents can cloud the brine.

How long does it take to cure?

Since salt diffuses into the meat, the time required does not depend on the weight of the piece of meat but rather on the distance that the salt has to travel. If the thickness is doubled, then the time increases by a factor of four. Even if the weight of the piece of meat doubles without changing its thickness, the time required remains nearly unchanged.

Here 'd' is the thickness of the thickest part in inches, 'r' is about 8 hours per square inch for flavor brining, 's' is 1 for flat steaks and 1.5 for round steaks. For full equilibrium brine the concentration must be the same at the center as it is on the surface, and the time required is about 120 hours per square inch.

Keep the whole process below 4 degrees C, use non-reactive containers and dispose of used brine without reuse.

The effect of salt on water.

When salt dissolves, there are measurable changes that occur to the liquid. This calculator shows those changes because they reveal how solutions of salts behave.

Density:

Salt water is denser than fresh water and its density changes in a predictable pattern. A 10% solution has a density of 1.071 g/ml while saturated salt water has a density of 1.197 g/ml. This explains why the traditional olive test works. If you put an egg in salt water, you can get a rough estimate of how salty the water is. An egg needs to be about 1.03 g/ml to float which corresponds to about 5% concentration of salt water.

Salt meter reading:

Industrial manufacturers often express the salt content in terms of SAL degrees, with 100 being fully saturated. A brine solution with a weight ratio of 10% has an SAL value of 38. This is just another name for saturation degree and also corresponds to the scale that can be read by an areometer directly immersed into liquid.

saturation level

At room temperature water can only dissolve about 36 grams of salt. Calculated per 100 grams of water, the resulting solution has a salinity of 26.4%. Heating the water brings few benefits. Sodium chloride is a typical solid whose solubility changes little with increasing temperature. Even when boiling, the dissolved amount increases to about 39 grams of salt per 100 grams of water.

freezing point

Each dissolved particle lowers the freezing point, and each unit of the salt's chemical formula produces two particles. A brine with 3.5% salt is roughly equivalent to seawater and freezes at a temperature close to -2 °C. With 10% salt, the freezing point is closer to -6 °C.

The lowest temperature is -21.1 degrees Celsius which corresponds to the eutectic point for a brine with 23.3% salt. Below this temperature no mixture of salt and water can remain liquid. This explains why on really cold days, road salt may not work any more.

Things that can't be explained by chemistry alone.

The calculations performed here are correct but actual values may vary. Vegetables give off water to the brine in the first day or two so the initial concentration of 3.5% will slowly decrease in your tank. This is normal and another reason to use total weight as a reference.

Meat marked "pre-seasoned" or with a certain percentage of solution has already been salted at the factory. If you add additional salt, it will make the turkey inedibly salty.

Curing salt is a different substance with different uses. The product "Prague powder" contains 6.25% sodium nitrite, which is expressed in parts per million (ppm) and regulated by law as to the maximum amount allowed, not by the salt content. The contents of this page do not apply to "Prague powder", nor can it be substituted for with coarse salt.

These results are estimates and are intended for use in cooking, fermentation or laboratory purposes. The properties of the solution will be calculated as pure sodium chloride at 20 degrees Celsius which may differ from actual ingredients. For food preservation please follow verified recipes and local food safety guidelines.