1 – Always ask for a Specification from the supplier. This describes the physical and chemical characteristics of what you bought. Like: Color, Aroma, Form (liquid, solid, etc.), pH, and so on.
2 – Okay – you just received the ingredient shipment. You asked that it be sent with a C of A (Certificate of Analysis). This is the proof that the product meets the requirements described in the Specification. First, compare the C of A to the Spec. and make sure the C of A meets the description in the Spec. Now look at a small sample of the ingredient. Does it match the description on the Spec? See the example below.
3 – Small companies (us included) have neither a chemist nor the equipment in-house to test the product. If you compared the physical characteristics and they all passed, then you can trust the chemical characteristics EXCEPT: you should have a program that specifies that you send samples to a testing lab on some schedule.
Every other month we sent samples of at least 3 of our oils out for various types of tests. Since we sell oil, we like to know what the Peroxide Value is. This tells us if the oil is “stable” and not going rancid. We usually test the peroxide value and compare it to the Spec.
Sometimes we’ll send samples of our ingredients out to test for bacteria, yeast and mold. Although – oils do not support microbial growth so we’ve never had a positive.
You don’t need a full lab to assess quality. You need eyes, nose and commons sense and a written procedure to randomly test your ingredients at a reliable lab.
If you need help finding a lab, let us know. We may be able to refer you to one near you. If these documents are still a mystery, come take a class. See the classes listed in this site.
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