As anticipated in the last days (read here), the scientists of EU project Quafety have been available on the platform of Tacler July, on Friday from 2 to 3 pm (GMT +2), to discuss some topics that are being studied within the project.A brief report from the third meeting which occurred on 25 July follows.
During the meeting, the scientists of Cardiff University (UK), Dr Hilary Rogers and Natasha Spadafora, and Matthew Bates for Markes International, company leader in innovative technology for trace organic analysis, were interviewed on ‘how to use volatiles to assess quality and shelf-life of fresh-cut produce’.
From the interview it resulted that the aim of this research group within Quafety Project is developing an easy to use system for assessing product quality and safety. As part of an assessment of input quality, effects of processing, or shelf life, this system enables you to collect volatile compounds with an easy to use collection system operated by minimally trained staff. You can then receive information on the relative quality of the product or markers for possible contamination with pathogens within a few days. The time limitation is dependent on transport of collection tubes to the laboratory; results from the analysis can be available within hours.
Matthew Bates has explained: “Markes International is responsible for providing the technical solution to Cardiff University to give the most robust and sensitive technique possible for the detection of VOCs (Volatile Organic Compounds), which make up the aroma of fruit and vegetables”. Natasha Spadafora has continued explaining that they have analysed VOCs, after head space was taken on sorbent tubes, by using 1) thermal desorption (TD) that is a sampling and injection technique, 2) gas chromatography (GC) that is a separation technique of compounds and 3) mass spectrometry (MS) that is a detection technique of compounds. Matthew Bates have said: “the combination of TD, GC and MS gives you a very powerful tool for quantitative and qualitative analysis of the compounds that are responsible for the odour.”
The scientists working on rocket and melon have found that wounding during processing, storage temperature and microbial spoilage are the main factors affecting the levels and the composition of VOC profiles.
Hilary Rogers has said that the whole aroma bouquet of a produce consists in hundreds of compounds, but she has explained: “We are now moving on to identify small numbers of compounds that are sufficient to discriminate between different states of the post-harvest material. In some cases, we are able to identify about 6 compounds that are a diagnostic of time and temperature of storage.”
The most important classes of compounds found in rocket are aldehydes and isothiocyantes while in melon are esters, ketones and alcohols.
Hilary Rogers has explained the differences between rocket and melon: “Melon is very sensitive to changes in temperature and we have studied the effect of cut size on melon showing that VOCs change with increased damage to the tissue. While, rocket leaves produce a much smaller number of VOCs at lower levels and so are more challenging to work with.”
You can find the full version of the interview and of the open discussion registering on www.tacler.com and visiting the Quafety section.
We wait until 19th September at 2.00 pm (GMT+2, Rome Time) on Tacler platform with Quafety scientists of University of Athens, Dr Eleftherios Drosinos and Dr Periklis Tzamalis will speak of ‘Quality and food safety management systems and voluntary certification schemes’.
Further info:
www.quafety.eu
www.freshplaza.com/sector/109/quafety
www.tacler.com
Contact:
Dr Hilary Rogers
Email: RogersHJ@cardiff.ac.uk