Real-time PCR

PCR (short for polymerase chain reaction) is an important analysis method in food analysis as well as in medical diagnostics.

A real-time PCR test duplicates and analyzes specific DNA sequences. In food analysis, PCR tests are used in many applications, e.g. for the detection of pathogenic microorganisms, for allergen identification, for the detection of genetically modified organisms (GMO) or for the identification of animal species. PCR tests offer many advantages: They are very specific, sensitive, robust, rapid and reliable. Moreover, the tests can be automated.

Advantages of real-time PCR tests

• Safe: specific and validated method
• Reliable: quality-controlled test kits
• User-friendly: easy-to-use, universal sample preparation
• Effective: capable to multiplex and quantify
• Versatile: many application areas

Real-time PCR procedure

The first step of all analysis is representative sampling and homogenization. After lysis of the organic cells of food tissue, the DNA will be prepared using different dedicated DNA or RNA preparation kits either for bacteria or viruses. SureFood® PREP Basic and SureFood® Prep Advanced kits are used for solid food and feed from plant or meat origin. For beverages specific DNA preparation kits will be used depending on the matrix, whereas the new QuickGEN line allows a straight forward easy handling.

The modular system of DNA preparation and DNA detection can be used independently. Amplification of the target DNA requires in addition to the relevant kits the use of a suitable thermocycler with two (FAM/HEX) up to 4 (FAM/HEX/ROX/Cy5) detection channels.

Application areas for PCR in food testing

• Allergens

​Food allergies can cause severe immunological reactions. In order to protect customers, food products have to be tested for allergenic substances. We offer a wide range of PCR kits for the detection of allergens such as soya, hazelnut, peanut, gluten, almond, celery, sesame, mustard, fish or crustaceans. We also offer multiplex assays for the simultaneous detection of multiple allergens (peanut/hazelnut/walnut and celery/soya/mustard).

• Animal speciation

​Species specification is of great interest: meat products can be falsified due to incorrect declaration (see horse meat scandal). Another application is the guarantee of religious dietary rules (halal, kosher). Our SureFood® Animal ID product line allows for sensitive testing for pork, beef, horse, donkey, chicken, turkey and other species. With the SureFood® Fish ID product line, we offer a wide range of PCR kits for the identification of fish species.

• Beverage spoilage

​When producing beverages, the detection of beverage spoilers is crucial. With the GEN-IAL® product line, we offer a wide range of screening kits for the detection of spoilage organisms in beer and wine production, e.g. Lactobacillus, Pediococcus, Megasphaera, Pectinatus, Dekkera bruxellensis or Oenococcus oeni. The test kits can be used for in-process control as well as for final product control.

• GMO

​In recent years, the worldwide production of genetically modified food has steadily increased. Since food products, which contain genetically modified organisms (GMO), must be labelled, the demand for sensitive test methods is increasing. Our SureFood® GMO product line allows for qualitative and quantitative detection of GMO – such as genetically modified maize, LibertyLink Rice or Roundup Ready Soya.

• Microbiology

Detection of microbiological contamination is one of the main fields of application of PCR in food analysis. Our product line SureFast® detects a wide range of pathogenic bacteria (e.g. Salmonella, Listeria, Legionella, E. coli, Staphylococcus aureus, Campylobacter), viruses (e.g. Norovirus, Hepatitis and Influenza) as well as yeasts and molds in food.