Mr. Steven Hogan is a natural health and nutrition enthusiast who shares his passion for living a gluten free lifestyle at http://www.glutenfreewire.com/
He has just written the following interesting article about "Laboratory Analysis Of Gluten Traces In Food Samples":
With awareness of gluten allergies afflicting a full one percent of the populations of North America and Europe, food researchers are learning the importance of proving foods are gluten free. However, few people understand the process by which foods are tested for gluten.
The laboratory analysis of gluten traces inside of food products is actually a wide range of tests, which can be used to test for anything from the amount of gluten in a prepackaged food product to the cleanliness of eating surfaces and utensils. What all of these tests have in common is that they are actually testing for the presence of proteins, of which gluten is among (gluten is actually a very specific type of protein that interacts poorly with the digestive systems of people who have allergies to glutenous proteins). Testing for these proteins, as well as a wide range of other proteins from a number of different sources, is possible through numerous testing methods.
The main type of gluten testing method on the market is a product known as enzyme linked immunosorbent assays. As their name implies, these tests are used to analyze enzymes, specifically those that interact with the human immune system. Given as gluten allergies are the result of the human immune system's elements located in the digestive system (where it hinders the absorption of nutrients, hence the “sorbent” element of the name), as well as the fact that gluten is a very specific kind of protein enzyme, the name is hardly unsurprising, all technical language aside. A shorthand version of these tests is ELISAs.
Some ELISA tests are qualitative, meaning that they are used to test for levels of gluten above a specific threshold, which will vary with the specific type of testing method and the chemical reactions that drive the test. If there is a level of glutenous proteins in a tested product above a certain level, it will react with the chemical compounds in the testing system and give a positive result. Among gluten testing methods, lateral flow devices are usually the ones providing qualitative test results.
Other ELISA tests are semi-quantitative, meaning that they provide a somewhat specific number (within certain levels of exactitude that can seem small but can none the less be quite significant statistically) relating to the levels of gluten proteins in a testing substance. Microwell tests are the most common ELISAs that provide semi-quantitative results.
Of the various forms of ELISAs used, the sandwich format tests are the most widely used. The gluten proteins (an antigen) binds to anti-bodies specifically formulated in order to be anti-gluten. The gluten proteins bind themselves to the anti-bodies, anti-bodies which are bound to a surface, typically a microwell plate. Once that's done, another, more specialized antibody, this one specifically geared towards a gluten enzyme, is applied on the microwell plate surface and then binds itself to the gluten already on the plate From there, a final substance is applied that will create a detectable way to determine the intensity of the gluten enzymes trapped on the plate.
Gluten ELISA Kit, manufactured and distributed by Astori Tecnica is recognized as a powerful screening test for detecting and quantify the presence of gluten traces in food and beverage samples.