Product Composition

I'm not sure if I am posting this in the right category.  I am trying to figure product compositions as I am new to them since our QC Manager left without teaching me and it is now my job to complete them.

We produce relish and brined vegetables and I can't figure out how to figure the vinegar for product compositions. We ferment our vegetables in tanks and some have a natural acid in them.  Do I have to account for the acid in the product or only the vinegar that is added after fermentation?  I'm sure this is confusing because it is to me.  If I have a recipe and we add 18 pounds of vinegar to a product that has a gross weight of 1800# am I correct that the percent composition would be 1% vinegar in the total product.  The product has a natural acid of 0.9 % acid.  And we are putting a 0.5 % acetic acid on it.  Would I figure the vinegar percent on how much we add to the product or the percent acetic acid that is in the product after the brine is added?

I am starting with a pickle that tests .9% acid.  We need a final acid of 0.7%.  In 90 gallons of brine we are putting 2 gallons of vinegar in to get a final acetic acid percent of 0.7% So would my product compostiton be the amount of vinegar we are adding to the pickles or the amount in the total product?

Hoping someone can help me understand this.

Hi jpotrz,

Hopefully I won't lead you wrong but here is my take on your query (if you have not answered it yet):

Your vinegar percent is the % of actual vinegar in the product when compared to the total weight of all the ingredients. So I would say yes, the % Vinegar (the actual ingredient) is 1% of your product.

Your acidity is determined from testing and can be different from the % vinegar if your product has other ingredients that can make it acidic also. Vinegar contributes to % acidity but if there are ingredients that are also acidic e.g ascorbic acid to prevent browning/oxidation, then these ingredients will also affect your acidity value.

Hope I helped.