The salinity of Kummok's brine

[Smokeville]

Hello all;

From what I understand, a typical brine of 1/2 gallon of water and 1 cup of kosher salt will read 60 on the salinity scale.

Kummok's brine recipe calls for 1 gallon of water, 1 cup of salt, and 1 quart of soy sauce, which has a LOT of salt.

Can anyone calculate what this does to the salinity? Does this bring it back up to 60?

Thanks, Rich

[pmmpete]

Brine recipes which call for a specific volume of salt, such as 1 cup of kosher salt in half a gallon of water, are less accurate and predictable than brine recipes which call for a specific weight of salt, because different kinds and brands of salt have different densities.  If you check the volume-to-weight conversion tables for salt in various books and internet sites, you get a pretty wide range of weights for a cup of regular table salt.  10 oz./cup is about in the middle of the range of weights for table salt.  Warren Anderson's book "Mastering the Craft of Making Sausage" lists weights of 22 grams/tbsp (i.e. 12.4 oz./cup) for regular salt and 12 grams/tbsp (i.e. 6.8 oz/cup) for kosher salt.  amazingribs.com contains the following conversion table for different kinds of salt:

1 tsp Morton's tables salt equals:
1.5 tsp Morton's kosher salt
1.8 tsp Diamond Crystal brand kosher salt
1.8 tsp Morton's pickling salt
3 to 4 or more tsp sea salt

Because of these differences in the density of salt, a brine recipe which specifies the quantity of salt by weight will be more predictable than a brine recipe which specifies the quantity of salt by volume.  There are charts which specify the volume of water and weight of salt required to prepare brines of different salinities.  For example, a brine which is 60 degrees SAL (salometer degrees) will contain 15.837 percent salt by weight.  That is 1.568 pounds (25.088 oz.) of salt per gallon of water, or .784 pounds (12.544 oz.) of salt per half gallon of water. There is a good article on making brines and salinity at http://www.wedlinydomowe.com/sausage-making/curing/making-brine which contains such charts.  See also "Preparation of Salt Brines for the Fishing Industry," Oregon Sea Grant Publication ORESU-H-99-002, which is available at http://seagrant.oregonstate.edu/sgpubs/onlinepubs/h99002.pdf .
 
Another way to prepare a brine with a specific salinity is to use a salinometer to measure the concentration of the brine, and to adjust the concentration by adding water or salt.  However, that takes a lot of trial and error.  It's faster to use the weights of salt specified on a salinity chart.

It is difficult to predict the salinity of Kummok's salmon brine because his recipe specifies a volume of salt rather than a weight of salt, and because different brands of soy sauce contain different concentrations of salt.  The only way to determine the salt concentration of Kummock's brine recipe for any specific kind of salt and specific brand of soy sauce is by mixing up the volumes of water, salt, and soy sauce which he recommends, and then measuring the concentration of the mixture with a salinometer, before adding any other ingredients such as sugar.

However, you can estimate the salt concentration produced by the water and salt components of Kummok's brine recipe based on the weight-to-volume conversion ratios described above.  Based on the conversion ratio for regular table salt of 10 oz./cup, a cup of regular table salt in half a gallon of water would produce a brine which is about 50 degrees SAL.  However, kosher salt weighs less per cup than regular salt.  Based on Anderson's conversion ratio for kosher salt of 6.8 oz./cup, a cup of kosher salt in half a gallon of water would produce a brine which is about 35 degrees SAL.  Kummok's brine recipe calls for 1 cup of pickling salt in a gallon of water, so if you look just at the salt and water portion of his brine recipe, based on Anderson's conversion ratio for kosher salt, the recipe would produce a brine which is about 18 degrees SAL.

A brine doesn't need to be 60 degrees SAL in order to salt fish for smoking, but the lower the salt concentration in the brine, the longer the fish needs to stay in the brine to reach a desired degree of saltiness.  Longer brining times increase the chances of bacterial growth and spoilage.

The advantage of being accurate and consistent about the salt concentration of your brines is that you can learn how long fish of a certain species, size, thickness, and with or without skin should be left in the brine to produce the degree of saltiness which you like.  If a batch of smoked fish comes out saltier than you prefer, don't leave the next batch in the brine as long.  When I try out a new brine recipe, I adjust the salinity of the water and salt portion of the brine to 60 degrees SAL, because I know how long I like to leave different kinds of fish in a brine of that concentration.

[ExpatCanadian]

Great answer!  I've actually been wondering about this myself....

[Smokeville]

Yes, pmmpete, great answer.

Next question regarding soy sauce. The nutrition label will tell the milligrams per tablespoon. Kikkoman has 920mg / 1tbsp. 1 quart has 64 tablespoons, so the soy sauce should have about 60 grams of sodium (rounded).

The sea salt I'm using is 300 grams per cup, but the label claims it has 390mg of sodium per gram, so the cup would contain 117 grams of sodium. If the sodium is what is important to salinity, then 1 quart of Kikkoman soy sauce would be equal to about 1/2 cup of my sea salt.

Does that make sense?

Many thanks, Rich

[slowpoke]

Thanks,I'm BMing this.Pmmpete