The Laboratory Notebook

Answering important questions about quality.

By Robert Green

This month we discuss issues involved in the testing of a “proprietary blend” and things to look for when you know you added a component to a product yet your analytical lab is unable to detect it.

Q. I am selling a finished product that I would like to have tested to confirm it meets label claim. One of the ingredients is a “proprietary blend” of several botanical extracts. Can I test for this ingredient?

A. The short answer is “it depends.” Now the longer answer…

Blends in a finished nutraceutical product can be tricky when it comes to analytical testing for a number of reasons. First, all of the actual components of the blend may not be identified on the label, or if identified, the amounts or ratio of each component in the blend is not disclosed. Since these proprietary blends are usually composed of botanicals it gets more complicated. If the blend contains standardized botanicals and the standardization information is provided (e.g. kola nut seed extract standardized to 10% caffeine) that’s one thing. More likely, however, is that either the botanicals are not standardized, or if they are, the standardization information is absent.

To ease the analytical burden, the first step is to ask your supplier for information sufficient to enable you to confirm the blend is in the product. While many times a supplier will provide this information, our experience is that more often it will not (that is why they call it a “proprietary blend”).

Without the requested information, the next step is for your analytical lab to consider the options and make recommendations. Analytical laboratories have the ability to conduct many different analyses using a wide variety of instrumentation, but there are two primary kinds of tests that we perform; quantitative and qualitative. Quantitative analyses are the most popular and usually the most informative because the results give you a number. If you want to know whether or not a particular ingredient meets label claim, then you want to know how much is in the product. Therefore, you want your lab to perform a quantitative analysis. If, however you just want to verify that the raw material you have is present (either because that is all you care about or you have a botanical without standardization information), then you may request a qualitative analysis, with a result of “yes” or “no” instead of “how much.” Even though you want a quantitative analysis of this blend, a qualitative analysis may still provide you with some comfort.

If your blend contains multiple botanical components with distinctive analytes, your lab should be able to confirm the presence or absence of each component in the blend. To do that, your lab would look for one or more analytes that would be present in each botanical. If the analyte(s) is/are present there is reason to believe that the botanical is present. If one or more of the analytes are not present, however, you may have a problem.

Of course, even this simple ap-proach can get complicated. It is important that the analyte the lab is looking for is exclusive to the botanical you seek in the product under analysis. Often the analytes we look for are present in a wide variety of botanicals, more than one of which may be in your product. If this is the case, finding it is less meaningful in confirming the existence of a particular component. To avoid this you and your lab should carefully review the entire contents in the product and the analytes of each component to select the appropriate analyte(s) to look for. If you can select analytes that your lab traditionally tests for, then the analysis should not be a big deal. But if the only selective analyte is something your lab does not usually test for, then some method development (and added expense) may be in order.

The bottom line is that analyzing a finished product is an involved and important process. Depending on the type of product it is (i.e. capsule, tablet, hard candy) and the nature of its ingredients, each step of the analysis must be carefully considered. Oftentimes a teeny-weenie capsule can be packed with 20 or more ingredients, each of which needs to be properly extracted and analyzed. Very rarely is there a one-size-fits-all approach that works for multiple finished products. If you talk to your lab about the sample and send them an ingredient list, they will be able to advise you on testing abilities and limitations.

Q. I have a powder blend of multiple ingredients, one of which is beta-carotene. I know the beta-carotene was added to the blend. The problem is that multiple laboratories have been unable to detect the beta-carotene in my product. Any ideas on why I keep getting this negative result?

A. Since you mentioned that multiple labs achieved similar results, let’s focus on the product and not the analytical process. The problem you are having with your product is not uncommon. We have to remember that the components we are dealing with in nutraceuticals can be very volatile and complex. Botanical components are especially sensitive. When they are part of the botanical, tucked away as nature intended, their properties are well protected. When you change the conditions of the botanical by drying, grinding, mixing or frying them, it is possible that you are affecting their composition and exposing these natural components to elements which make them susceptible to decomposition. Manipulation of synthetic ingredients can also degrade them. For many ingredients degradation occurs simply with the passage of time.

The disappointing test results may be the effect of several factors, the first of which is mentioned above—processing. Another factor is exposure to various environmental conditions. Light is a big one. Many substances have a tendency to degrade in natural light. Beta-carotene is such a component. Moisture, heat and pH are also important factors. If your manufacturing, packaging and storing processes do not take these into account, this could be a possible explanation.

It is also possible something in your product is incompatible with the beta-carotene, causing it to degrade.

As you can see, the problem is not unique, but determining the cause is not always simple. You and your lab should undertake some detective work to see if a cause can be identified.NW