If 2 cups of Himalayan salt is used in making 60 gallons of soup, how much sodium does this contribute to a 24 oz. soup serving?

Question

We have a local soup kitchen that provides 24 ounce containers of soup. There is no nutritional profile posted on the containers, and I'm curious as to how much of the standard (American Heart Association) daily sodium limits 1500 milligram=0.05291094 ounces (for high-blood pressure people] and (FDA?) 2300 milligram = 0.08113011 ounces (for people in general) is provided.

I've been told that 2 cups of Himalayan salt are used for each 60 gallons of soup.

Even though Himalayan salt and table salt are both about 98% sodium chloride--perhaps Himalayan is less densely packed--I have before me a Trader Joe's bottle of Pink Salt Crystals (which I'll assume qualifies as Himalayan). The label says that one teaspoon provides 4 x 470 = 1880 milligram, while the web says a teaspoon of table salt has 2,325 milligrams (as indicated closely above, i. e., 2,300).

Answer 1

This is one part math problem, and one part cooking.

First the math

In a 60 gallon batch, there are 320 24-oz servings.

2 cups is 96 teaspoons...divided into 320 servings is 0.3 teaspoons of salt per 24oz serving.

Now, one teaspoon of table salt has about 2,325 milligrams (mg) of sodium (though, this will vary a bit depending on your salt source, grind size, etc--coarser grinds will have more air between the grains of salt for the same volume). Your salt sample is 1880 mg/teaspoon, so we can consider that a lower bound.

0.3 teaspoons salt will be about 560-700mg of sodium.

Therefore, each 24oz serving of soup would have roughly 560-700mg of added sodium...

And now the cooking part

Salt isn't the only source of sodium in a dish. Particularly when other ingredients might be prepared separately. In a soup, there may be ingredients like broth, bullion, beans, seasoning mixes, canned tomato, bacon/ham/sausage, etc which can all contribute sodium.

The added sodium would be around 560-700mg per 24 ounces of soup, but the total sodium may be higher.

Answer 2

Well, a gallon is 128 ounces. So, 60 gallons is 7,680 ounces. There are 16 (fluid) ounces in two cups. So, each ounce of soup contains 16/7680 =1/480 = 0.00208333 ounces of Himalayan salt. Multiplying this by 24 gives us one-twentieth (1/20) ounces of this salt in each 24 ounce container. This is equivalent to 1417.48 milligrams of Himalayan salt.

Let's multiply this 1417.48 by the ratio of 1,880 to 2,325 (see question), giving us 1146.18 milligrams of sodium in each container.