Food testing strips are products that help determine whether or not food contains bacteria that can cause
foodborne illness
Foodborne illness (also known as foodborne disease and food poisoning) is any illness resulting from the contamination of food by pathogenic bacteria, viruses, or parasites,
as well as prions (the agents of mad cow disease), and toxins such ...
. These products can typically be used on food, water, and hard surfaces, and are often designed for quick and easy home and commercial use.
Categories
Currently, there are two categories of food testing strips on the market.
One type of food testing strip is an assay
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
reactant test, which requires the strip to be dipped into a blended mixture of food or test samples,
distilled water and a
reagent
In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...
. Such tests are designed specifically to detect those strains of ''
Listeria
''Listeria'' is a genus of bacteria that acts as an intracellular parasite in mammals. As of 2024, 28 species have been identified. The genus is named in honour of the British pioneer of sterile surgery Joseph Lister. ''Listeria'' species ...
'', ''
Campylobacter'', ''
E.coli'' and ''
Salmonella
''Salmonella'' is a genus of bacillus (shape), rod-shaped, (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two known species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' ...
'' that are harmful to humans.
[ https://www.fsis.usda.gov/sites/default/files/media_file/documents/Validated-Test-Kit.pdf]
A second type of food testing strip is a gram-negative swab, which is usually administered directly to the food itself. Gram-negative swabs generally work faster than enzyme reactant strips, but they differ in that the gram-negative swabs are designed to detect a broad group of organisms, not just those that can cause foodborne illness in humans.
Usage
The enzyme reactant test strips react when the buffer solution breaks the bacterial wall. This breach releases enzymes, which react upon contact to the enzyme test strips.
The gram-negative reactant activates when components of the gram-negative cell wall or specific enzymes are present, causing the swab itself to change color. This is not directly indicative of the presence or absence of human pathogen in the test sample.
People are now working on new ways to enhance these pathogen strips with silk pills and new
nano-fiber membrane technology.
See also
*
Food safety
Food safety (or food hygiene) is used as a scientific method/discipline describing handling, food processing, preparation, and food storage, storage of food in ways that prevent foodborne illness. The occurrence of two or more cases of a simi ...
References
* Olafsdottir, Sigridur and Olaffson, D.R. "02/15/05" United States Patent Washington D.C. United States Patent and Trademark Office
* Zakrzewski, Z., et al., "The Effects of Adjuvants on the Physical Properties and Active-Substance Release from Oral Suspensions," Goldschmidt Informiert, 57:14-17 (1982).
* Lowenkamp, Bill “Material Safety Data Sheet (MSDS) for ''Salmonella/E.Coli'' Testing strips“ Hazleshurst, MS Lowenkamp Labs (2007)
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External links
Article on Instant Test Strips by Sean Henahan, Access Excellence
Food safety