# SCALE ACCURACY for SPICES and CURE



## sprky (Apr 10, 2020)

First off I'm NOT going to go into great detail on the subject of cures. The science and process have been done numerous times, all ya have to do is a search and there's a wealth of info to be found on here. I am going to attempt to simplify what is needed, in accuracy. I spent MANY hours researching, this subject. I had questions, which I think others do or will as well. So Hopefully I can answer some of them and clear some thing up. This all applys to what ever measurement you are using lb, oz, g, etc.

Not every scale is the same. While they may appear to be the same, they may be totally different. Here's why.
The terms *accuracy, precision, and resolution* are important descriptors of the properties of weighing scales. Although these terms have different and distinct meanings, they are often confused with one another. It is *important *that they not be used alone to determine the quality or exactness of a scale.
*ACCURACY* is the measure of the degree of closeness of the average value of an object’s displayed weight to the object’s actual weight. If, on average, a scale indicates that a 200 lb reference weight weighs 200.20 lb, then the scale is *accurate to within 0.20 lb in 200 lb, or 0.1%*.
*PRECISION *is a measure of the repeatability of an object’s displayed weight for multiple weighing of the same object.
Example, if the displayed weights of an object that weighs 200 lb are 200.20, 200.30, 200.15, 200.10, and 200.25 lb, then the average displayed weight is still 200.20 lb, but the measured values deviate by as much as 0.10 lb with respect to this average. Thus the precision is expressed as ±0.10 lb, *meaning that the fluctuations are limited to 0.10 lb in either direction*. In a similar example, if the displayed weights are 200.20, 200.40, 200.10, 200.00 and 200.30, the average is still 200.20 lb, and the accuracy is still 0.20 lb or 0.1%. *However, the deviation is larger (0.20 lb) and the precision would be ±0.20 lb, not ±0.10 lb.
RESOLUTION* is the smallest increment of weight that can be detected or displayed on a scale. In the examples cited above for precision, the readout appears to show changes in 0.01 increments, but in fact the digits change by 0.05, and 0.1 lb. Hence the *PRECISION*
The info above came from https://www.homscales.com/sites/def...olution-in-weight-measurements-17-02-27_0.pdf

Armed with the info i found/learned I came to the conclusion that a scale that reads in 0.01 may be just as accurate as one that reads 0.1, or even 1 (I know the 1 is a stretch). There for unless you are measuring out *"PURE Nitrate or Nitrite" *you do NOT need an extremity accurate scale. You could get by using one that uses 1 but myself Id go nothing less then 0.1 (better consistency, 1 rounds too much when using spices). Heres why you can use a lesser accurate scale using cure #1 or #2. Using the recommended amount of 1 teaspoon of cure for 5 pounds of meat there is a margin of error to keep it under the max allowed. 1 teaspoon weighs ~5.46 g. I have spoke with several reputable cure suppliers, and they all have said that there is a Margin of error to be below the max allowed. Several went on to say that if your scale only reads in 1 g increments to use 1 g per pound of meat, and add a few days to the cure time. I crunched the numbers to make sure and yes its below the max PPM.


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## BandCollector (Apr 10, 2020)

Great read and information.

Thanks 

 sprky
 ,

John


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## thirdeye (Apr 10, 2020)

Good info on accuracy of scales, and for as little as $.25 you can verify your scale each time for accuracy of small amounts.  A nickle weighs 5 grams.  It's good to bracket the weight range you will be using just to give yourself some peace of mind you are working within the acceptable margin of error. So if you are measuring amounts between 7g and 15g, use one nickle to confirm 5g, and 4 nickels to confirm 20g, in theory anything in between should be accurate.  I don't recall the price of my 100g and 500g weights, but they are reasonable if you use several different scales. 



sprky said:


> 1 teaspoon weighs ~5.46 g. I have spoke with several reputable cure suppliers, and they all have said that there is a Margin of error to be below the max allowed.



Here is where a slightly different discussion can take place.  There are two reasons it's recommended to weight Cure #1 and one of the accepted (weight) constants is 2.5g/1000g of meat, used for dry curing pork belly for bacon.  That constant can be improved if you account for the salt carrier in Cure #1, But for point of conversation either will give us confidence when using Cure #1.  The other reason is that measuring spoons are notoriously inaccurate.  For a write-up I did years ago I used three different teaspoons to measure the weight of Cure #1, and repeated the measuring three times for a total of nine tests.  Here are the results with very minor rounding:

Cure #1
Teaspoon A:  3.9g/teaspoon
Teaspoon B:  4.1g/teaspoon
Teaspoon B:  4.2g/teaspoon

I'm curious where you got your ~5.46g of  Cure #1 per teaspoon, and if you happened to use more than one teaspoon to confirm that?  One factor could be the grind of the salt carrier varies from manufacturer to manufacturer. For example, a teaspoon of Diamond Crystal kosher salt weights less than a teaspoon of Morton's Kosher because Diamond Crystal has larger grains. The finer salts used when mixing Cure #1 may have a small affect on the measurements. 

All that said, I just tossed this on the table for conversations purposes.  For decades I used teaspoon measurements for both Tender Quick and Cure #1, as did most people because that was how we were taught. I now use a gram scale, and do recommend their use.


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## sprky (Apr 10, 2020)

thirdeye said:


> I'm curious where you got your ~5.46g of  Cure #1 per teaspoon, and if you happened to use more than one teaspoon to confirm that?
> I dint even weigh a teaspoon. I got that figure from another post on here. I dont recall which post I have looked at so many. I wrote in notes i keep for info I think may be useful. Heck I might have even wrote it down wrong, was quite a while back i came across it.
> 
> All that said, I just tossed this on the table for conversations purposes.
> ...


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