Food safety question growing in global importance

The firm said some of its big customers in the food market want to standardise their methods worldwide because of their high throughputs.

This means they are opting for automated sample preparation and PCR set-up so it has a low burden on manual work.

The firm develops detection systems for pathogenic, spoilage and genetically modified organisms based on real-time polymerase chain reaction (PCR) and kits for sample preparation.

Core competence​

Dr Florian Waldherr, key account manager at Biotecon Diagnostics, told FoodQualityNews.com that its core competence was the development of real-time PCR assays for application in food testing.

“This means we have four main fields, on the one hand microbiological assays like pathogens or spoilage organisms, we do detect food allergens, genetically modified organisms and we also detect animal species like for example horse meat, beef meat and pork meat,” ​he said at Analytica 2014 in Munich.

Waldherr said customer demand was focussing around the reliability and the validation of the kits.

“That’s why we do a lot in our own validation before we release a kit and when we have released it we do approvals together with AOAC, for example if you are in the US market or if you are in the European market, with NordVal or Microval which do another validation​.”

Automation in the lab​

Waldherr said the role of automation was growing in importance.

“You do a lot of pipetting for PCR and for sample preparation and this is simple work and you keep potential working force in your laboratory if you do an automatisation​.”    

He gave an example of automation’s role in Salmonella food testing.

“You do a normal enrichment for Salmonella, in buffered peptone water, and then you take out some of your enrichment broth, place it in the robot and then the robot reads your barcoded sample puts it in your system and then does a DNA isolation based on magnetic beads. ​

“It stores the DNA on an elution plate and prepares the master mix and it puts the master mix in your consumable PCR plate adds to DNA and then, if this is finished, the user comes to the machine takes out the plate and puts it in to the PCR cycler.​

“They get the result and then if they want to offer a software for interpretation of the PCR data and they get a red green answer for the question is there Salmonella in the sample or not.”   ​

Foodproof device​

Waldherr said its Foodproof Salmonella Enteritidis and Typhimurium Detection lyokit which enables identification of both serotypes in one assay.

The kits prevent false negatives by internal control and stop carry-over contamination using Uracil-N-Glycosylase.

It is validated to detect 1-10 cfu/5g including enrichment and has AOAC, Microval and NordVal approval.

“If we have a Foodproof Salmonella detection kit we have an enrichment possibility for the DNA, you have to take out the DNA of your enrichment broth contains, if it’s positive, Salmonella DNA.​

“Therefore you have different possibilities, you can do it manually, which means you use a simple lysis buffer where you take your enrichment, put it through the lysis buffer, heat it and centrifuge it and your supernatant contains the DNA which you can use for PCR directly. ​

“Then you take our lyophilized Salmonella kit, this means already you have all your master mix lyophilized in the PCR consumable and just add the  supernatant from your lysis to the plate, put it in the PCR cycler and about, depending on the cycler, about 1 and a half hours later, you get your results.”     ​