When recipe calls for a tablespoon of “kosher salt” that seems like a simple instruction, right?

Perhaps not… Many recipes call for a specific amount of “kosher salt”, but we’ve noticed that sometimes it just felt (or later tasted) like the wrong amount to use. Through our introduction to kosher salt and other educational resources, it was clear that kosher salt and table salt are pretty different and we have been using kosher salt for our normal everyday cooking for years. However, as we really didn’t have any choices for kosher salt locally, we have been using Morton’s Coarse Kosher salt by default. We noted that occasionally Diamond Crystal Kosher salt was being recommended specifically, and it eventually dawned on us that there might be significant variation between brands of kosher salt that might be driving this observation.

Supplies

• different types of salt:
  • Diamond Crystal Kosher salt
  • Morton Coarse Kosher salt*
  • Great Value salt (non-iodized, “table” salt)
  • Flor de sal d’es trenc (Fleur de sel from Mallorca)
• kitchen scale
• small containers

Steps

Step 1: Gather your supplies.

Salts types investigated for this post.

Step 2: Weigh the same amount of each type of salt. We measured out 20g of each type.

Each container has 20 grams of salt in it.

*Note: the photos in this post all show a version of Morton Kosher salt that is referred to in the data tables below as “old box”. We have used Morton Kosher salt in the primary testing facility for years, and this box initially seemed… different. Based on the measurements conducted, and some online comments, suspicions grew that the “old box” batch was significantly different (but is it a statistically significant difference?? more on that later) than what we were used to. So, after primary data collection occurred, a new box was acquired and results for that are noted in the data tables as “new box”.

Observations

The differences in volume are pretty startling:

The Flor de sal and Diamond natural have significantly more volume than the Morton* and Great Value varieties for the same mass (20 g).

From the above, it is easy to see that if a recipe simply calls for a volume of kosher salt without telling you what brand was used, the results could vary significantly.

Another way to think about this is for a given volume, how different is the mass of salt:

For the same (50mL) volume of salt, the mass of the salt varies significantly by type and brand (see *note about Morton below).

Results

There is a HUGE difference between the Morton Kosher salt and either the Diamond or Flor de sal. Recipes calibrated for one type of salt will need adjustments if a different type of salt is used. Stating the amount of salt to use by mass would be best (other than textural aspects of “saltiness” you would at least have the same number of moles of NaCl required by the recipe).

Final Words

Dear recipe makers – please tell us what type of salt you use (and it would be a bonus if you weigh it)! While most may be familiar that kosher and table salts are different, the fact that two main brands of kosher salt can be that different can lead to huge differences in recipe results.