Cyclopropane fatty acids (CPFA), as lactobacillic acid and dihydrosterculic acid, are components of bacterial membranes and have been recently detected in milk and in dairy products from cows fed with corn silage. In this paper, a specific quantitative gas chromatography-mass spectrometry (GC-MS) method for the detection of CPFA in cheeses was developed, and the quality parameters of the method (limit of detection, limit of quantitation, and intralaboratory precision) were assessed. Limit of detection and quantitation of CPFA were, respectively, 60 and 200 mg/kg of cheese fat, and the intralaboratory precision, determined on three concentration levels, satisfied the Horwitz equation. This method was applied to 304 samples of PDO cheeses of certified origin, including Parmigiano Reggiano (Italy), Grana Padano (Italy), Fontina (Italy), Comté (France), and Gruyère (Switzerland). Results showed that CPFA were absent in all of the cheeses whose Production Specification Rules expressly forbid the use of silages (Parmigiano Reggiano, Fontina, Comté, and Gruyère). CPFA were instead present in variable concentrations (300-830 mg/kg of fat) in all of the samples of Grana Padano cheese (silages admitted). A mix of grated Parmigiano Reggiano and Grana Padano was also prepared, showing that the method is able to detect the counterfeiting of Parmigiano Reggiano with other cheeses up to 10-20% Grana Padano content. These results support the hypothesis that CPFA can be used as a marker of silage feedings for cheeses, and the data reported can be considered a first attempt to create a database for CPFA presence in PDO cheeses.

No abstract

The atmospheric double barrier discharge (DBD) plasma technology is a promising tool in food industry as an alternative to traditional food preservation methods. However, the effect of the reactive chemical species generated during the treatment on the qualitative and quantitative content of bioactive compounds in food is still little studied, as well as there are no data concerning potential deleterious effects of DBD treated foods on human cells. We measured antioxidants content and antioxidant capacity of DBD-treated minimally processed Pink Lady® apples in comparison with untreated matched samples. Moreover, we compared the effects of polyphenols extracts obtained from DBD-treated apples on cell viability, reactive oxygen species production and phase II enzyme activation. The results show that the plasma treatment causes a slight reduction of antioxidant content and antioxidant capacity. Noteworthy, apple treated polyphenols extracts do not reduce cell viability and do not suppress the beneficial physiological cell response to oxidative stress.

No abstract

No abstract