do you know how much nitrite is uptaked into the meat without injection? A little inside baseball,,,, only about 10% of what’s in the brine. So an equilibrium brine made up of water with not 156ppm nitrite but 1973ppm nitrite will impart only 197ppm nitrite at 10% uptake. This is a USDA recommended brine, btw, so on the equilibrium brine you will be lucky to uptake above 50ppm nitrite. This seems to work fine but lots of people don’t understand how brines work, they are based on 10% uptake.
Yes, I agree, and your info is good for many aapplications. Direct application of dry salt and cure is much more efficient, as is pumping, thus their use commercially to almost the complete exclusion of immersion. For big chunks of meat, I also like the much more efficient dry rub cure.
Your description above is Method One of the two recognized FSIS calculation methods, pumped or short immersion where weight pickup is used. This is the overwhelming method commercially due to efficiency, time, and cost. So it is emphasized a lot and folks forget it is not the only method.
However, the FSIS Inspectors Handbook recognizes a 2nd method, long term immersion curing. While not used commercially, this is a common method home makers use with liquid brines, where meat is kept in brine for up to weeks instead of hours, or pumped/massaged/cooked in hours as most commercial operations do. Because it's a common home method, it's important to remember it exists and is different from the weight gain calculations.
From the USFDA FSIS Inspectors Handbook:
Nitrite in Immersed Products
In immersion curing, the submerged meat or poultry absorbs the cover pickle solution, slowly,
over a long period of time.
There are two recognized methods for calculating the allowable
ingoing amount of nitrite in immersion cured products. The method used depends on the
mechanism of movement of nitrite within the meat and/or poultry/pickle system and into the meat,
meat byproduct, or poultry tissue itself.
[...]
Method Two
The second method assumes that the submerged meat, meat byproduct, or poultry and the
cover pickle act as a single system.
Over time, the ingredients in the pickle, such as nitrite
and salt, migrate into the meat, meat byproduct, and poultry until levels in the tissue and in
the pickle are balanced. This system is actually very complex and dynamic, with
components in constant motion, but it will reach and maintain a state of equilibrium.
[...]
--Note: the
calculation method for nitrite in immersion cured bacon is the same as that for nitrite in other
immersion cured products. Refer to pages 21-24
--------
Additionally, FSIS lists numerous methods it calls uncommon commercially, but gives guidance to inspectors on using the two published calculation methods. One of those is injection with, followed by immersion in, an Equilibrium brine to speed the equilibrium process, using method 2. This is what I primarily use for small chunks like buckboard bacon where I'm doing several small pieces at once.
If readers want more information along with time delay nitrate diffusion tests in a meatblock via diffusion, I refer you to Dr. Greg Blonder, former Director of Bell Labs, who maintains a site on meat science and publishes on Equilibrium curing at genuineideas dot com.
While not of interest to many, it's nice to see you take the numbers seriously and post info that will help folks learn.
Opinions and bad info abound on internet, and since I am definitely not interested in having an argument, I take my info directly from the FSIS Inspectors Handbook and their indepth calculation examples.
As these last couple posts show, it can be hard to calculate nitrite levels, multiple methods exist, and can take a bit of reasoning. It's just a side discussion to meat making, but good to have once in a while, while not losing sight of the fun and simplicity. But We all have the same goal-- to make great tasting healthy meat products safely.
Best regards ;)