Calculating PPM

[DanMcG]

Could someone help me out here, math is not my strong point. I was looking at 2 recipes on Len Poli's site both were with brines. The first one, a corned beef http://lpoli.50webs.com/index_files/Corned_Beef.pdf
uses 2.5 qt.s (2400 ml)of water and 40 grams of cure #1 and it's mentioned that that equals 148 ppm of cure in the brine.
The second a Canadian style bacon;
http://lpoli.50webs.com/index_files/Can ... on-Len.pdf
uses 2 qt.s (2000g's) of water and only 5.8 grams of #1 and it says the brine contains 146 ppm of nitrite.
How can they have relatively the same percentage of cure when one has 25% more water but 6 times the amount of cure?
The first one I come up with 940ppm and the second one 168ppm. I did some rounding off but I still must be missing something. Is there a simple way for me to calculate it?
Thanks, Dan

[grisell]

Could it be that cure and brine are two different things? I mean that the cure contains other things than nitrite and they are calculating on the nitrite amount?

[DanMcG]

They both use cure #1 which is 6.25% nitrite in a brine. (I used 6% for my calculations)

Maybe I'm not understanding what you're saying. Isn't PPM the amount of nitite in the water?
Apples for apples I can't see how they can be similar in PPM, but I'll be the first to admit I don't fully understand the science of sausage making yet.

[grisell]

First one:

2400 ml + 40 grams = 2440 g in total (ca)
6.25% of 40 gram = 6.25/100 * 40 = 2.5 g nitrite
2.5 g of 2440 g = 2.5/2440 * 1,000,000 = 1025 ppm

Second one:

2000 g + 5.8 g = 2005.8 g
6.25% of 5.8 g = 0.3625 g nitrite
0.3625 g of 2005.8 g = 0.3625/2005.8 * 1,000,000 = 181 ppm

Note that I have assumed the density of the cure to be 1.0 in calculation of the total volume, which is incorrect but of no practical importance.

Where is the salt? That has to be accounted for. Also any other ingredient s.a. sugar.

[Oddley]

I don't think it is relevant calculating the amount of nitrites in the brine. what is relevant is calculating the ingoing amount of nitrites into the meat.

So using the PROCESSING INSPECTORS' CALCULATIONS HANDBOOK

Corned_Beef.pdf

grams premixed cure × % Nitrite in mix × % Pump × 1000000
----------------------------------------------------------------------------- = PPM
100 ×100 × Weight of Brine

60 × 6.25 × 15 × 1000000
---------------------------------------- = 216 ppm
100 ×100 × 2600

For ease, I calculated the second one as an equalized immersion cure.

Canadian Bacon-Len.pdf Equalibrium cure

grams premixed cure # 1 × % Nitrite in mix × 1,000,000
------------------------------------------------------------------------------- = ppm
100 × (green weight (gram) meat block + gram pickle)

7 × 6.25 × 1,000,000
---------------------------- = 130 ppm
100 × (2270 + 1104)

[wheels]

Oddley

I'm confused about your gram pickle figure in the second calc. The total pickle seems to be 2170 not 1104?

Also, why an equilibrium calculation for a pumped piece of meat? I know that it's subsequently brined for 3 days but that only equates to 1.3 days per kg, which is a maximum of 50% towards equilibrium (that is, if we accept that it will perform like a fresh brine cured piece of meat when it has already had a 10% pump).

There must be something I've missed here?

Phil

[Oddley]

This is the recipe that I used from len:

Canadian Style Bacon - American Version

Ingredient Metric:
2270.0 g. Pork loin
56.0 g Salt
26.0 g Sugar
7.0 g Cure #1
15.0 ml Liquid hickory smoke
1000.0 ml Ice water

It seems to me the pork loin weighs 2270 the rest weighs 1104g. 2270 + 1140 = 3410 so I don't understand what the problem is.

grams premixed cure # 1 × % Nitrite in mix × 1,000,000
------------------------------------------------------------------------------- = ppm
100 × (green weight (gram) meat block + gram pickle)

I understand what you are saying. I think that the time in the brine and the 5% pump, plus quite a lot of the dissipation in the first couple of days, as there is no linear dissipation would result in approx a equalization cure.

So instead of doing complicated calcs and frazzing my brain I did a simple equalization cure, so OK shoot me..

So this was sort of a ball park figure of guess work. If you can work out accurately this sort of cure, I bow to your knowledge and wish you would explain it to me.

[wheels]

Ah, there's some confusion here, the link that Dan posted above is:

http://lpoli.50webs.com/index_files/Can ... on-Len.pdf

It has a 10% pump and 2000ml water in the cure. You seem to have a different version?

My initial calcs only show <20 PPM nitrite from the pump and <80 PPM from the brine at equilibrium (which it will get no-where near).

Dan, if there was no brine period, I'd say it was a typo and that the cure #1 should be 58gm - this would give a sensible pumped cure then. It's a long shot but it may be worth emailing Len to check.

If you can work out accurately this sort of cure, I bow to your knowledge and wish you would explain it to me.

Would that I could...would that I could...

...I was hoping you'd explain it to me!

Phil

[DanMcG]

I guess I better start studying, because you guys totally lost me.
One last dumb question.
If you make up a brine with X PPM what does the amount of pump have to do with it, the brine is still X PPM
Like I said I better do more studying.
Thanks all for your input, it will make sense to me sometime.

[wheels]

I'll try.

Assume you are using 100% nitrite - not cure #1 - real 100% nitrite, no salt or anything in it, just nitrite.

If you add 1gm of it to 999gm of water, you'll have 1000gm of brine - that's one in a thousand parts nitrite (1/1000). But we want to know what that is in Parts Per Million. Well, as a million is 1000 x 1000 we just multiply by 1000 to get the answer. So our 1gm nitrite to 999gm water is 1000PPM nitrite.

Ah, but that's the brine, we want to know what's in the meat. If we have a piece of meat that weighs 1000gm and we want to pump it at 10%, the amount of grams to inject will be 1000 divided by 10: that's 1000/10 = 100 gm of brine.

When we've done this our meat may have 100gm of brine in it but this brine will only contain 0.1gm nitrite - our original brine had 1gm nitrite in 1000gm of the brine, our 100gm injected is a tenth of the original and so contains a tenth of the nitrite

So we've got 0.1gm of pure nitrite in 1000gm meat. We already know that to calculate the PPM we just multiply by 1000 which is 0.1 x 1000 = 100PPM.

In reality the calculation is done like Oddley did the corned beef one above:

Corned_Beef.pdf

grams premixed cure × % Nitrite in mix × % Pump × 1000000
----------------------------------------------------------------------------- = PPM
100 ×100 × Weight of Brine

60 × 6.25 × 15 × 1000000
---------------------------------------- = 216 ppm
100 ×100 × 2600

Our example would be:

1 x 100 x 10 x 1000000
---------------------------------------- = 100 PPM
100 x 100 x 1000

You will note that the weight of the meat doesn't even enter into the calculations. Why? Well, because we inject at 10% of the meat's weight, the ratio of cure to meat will be the same for this brine irrespective of the meat weight. e.g 2000gm of meat would be injected with 200gm of cure containing 0.2gm nitrite. That's exactly the same as 0.1gm nitrite in 1000gm meat, so it would still be 100PPM.

I hope this clarifies rather than confuses.

Phil

[grisell]

Oh, we are injecting? Sorry, I missed that.

[DanMcG]

Thanks everyone for your patience and help, I think there's a chance that I just might figure this out.

[DanMcG]

I think I got this right but could someone check it for me?
I want to make up some beef jerky in an immersion pickle.
I’ll use ;
2.5 quarts of water= 2365 g
5 pounds beef (cut in 7 mm / ¼”slices) =2268g
Cure # 1 with 6.25% nitrite

Looking for a maximum 200PPM of nitrite.

N= 200 x Grams Pickle + Grams Meat
1,000,000

200 x (2365 + 2268) = .9266 grams of nitrite
1,000,000

Nitrite---------- .9266 = 14.8 grams of cure # 1
% N in cure #1 .0625


And just a double check;

Cure mix x % nitrite x 1,000,000 = 200 PPM
Grams of pickle + Grams of meat

14.8 x .0625 x 1,000,000 =200 PPM
4633

Now if this is right, what would be the minimal amount of time it would take to get to equilibrium? 12 hours?
The above formula has no salt, sugar or spice added to it just for simplification, but I will add it in the brine weight and recalculate when the time comes.

Thanks again, understanding what I’m doing does make it more enjoyable.
Dan

[wheels]

I bloomin' well hate immersion cures! You work out one part of it and it then throws a load more questions at you!

...oh, and I should say that i don't make jerky either! That said, and for what it's worth, I'll have a bash at answering your question.

Dan, the figures you calculated are correct according to one of the methods given in the FDA Meat Inspectors' handbook, and that method seems to be the correct one for your small pieces of meat. However, the handbook gives no instruction on curing a number of pieces of meat in one brine, nor any time-scale.

We can only assume that with a number of small pieces of meat we use the 'total weight' in the calculation. As to the time-scale, maybe 12 hours is fine, who knows? I'm guessing it may be, but in any case, longer won't harm as you've calculated the maximum PPM it can possibly get to even if it's left for weeks (that's according to the FDA anyway). Having said that, I've immersion cured small chunks of pork for luncheon meats and they're fine in about 12 hours. We also know from NCPaul's tests that a 1kg piece of meat is 45% cured in 24 hours (but the cure is in the outer parts mainly). I reckon that if it was me doing it, I'd give 'em 24 hours or so.

Sorry, I've probably raised more questions than I've answered.

Phil

[grisell]

I bloomin' well hate immersion cures! You work out one part of it and it then throws a load more questions at you!

[---]

I use dry curing whenever I can because of this reason, but maybe it isn't an alternative for you, Dan?