40 research outputs found
Non thermal plasma as an alternative tool for milk processing
In this study, a novel cold plasma system has been tested and
optimized as an alternative processing method for decontamination
of E. coli. Salmonella Typhirimium and Staphylococcus aureus in
milk samples. Further to assessing the system for optimal decontamination
parameters, changes to the chemical composition and
sensory qualities of milk were also tested by well established
methods such as GC\u2013MS, SDS-PAGE and colorimetric testing. The
inactivation of test microorganisms reached the highest level after
3 minutes of application which was followed by a slower rate of
inactivation. Plasma application did not significantly affect the pH,
colour, proteins, fatty acid composition, and volatile compounds of milk samples. The findings of this work have preliminarily
established the feasibility of using plasma technology for milk
decontamination while retaining the nutritional and sensory quality.
If established this technology will provide both health and
economical impacts
Biochemical changes to milk following treatment by a novel, cold atmospheric plasma system
It has previously been shown that non-thermal (i.e., cold) plasma can successfully decontaminate milk from Escherichia coli. This study investigated the possible biochemical changes to the protein, free fatty acids and volatiles profiles of whole raw milk samples following application of cold plasma. Raw milk was treated with a cold plasma system at intervals of 0, 3, 6, 9, 12, 15 and 20min. Significant changes were observed for 1 octanol (P<0.05), 2 heptanone (P<0.01), 2 hexenal (P<0.01), 2 octenal (P<0.05), nonanal and benzaldehyde (P<0.001). Plasma treatment did not result in significant changes to the lipid composition of raw milk. However, exposure to cold plasma significantly increased the total aldehyde content following 20min treatment. No significant difference was observed in the total ketone or alcohol levels
The effect of low temperature plasma on volatile profile of milk
In this study, the time dependent effect of non thermal plasma (NTP) application (15 kV, AC power supply) on the volatile profile of milk was investigated by gas chromatography\u2013mass spectrometry, based on solid-phase microextraction (SPME) analysis. Plasma was applied at time intervals of 0, 3, 6, 9, 12, 15 and 20 min. More than 50 volatile organic compounds were separated and identified. The exposure to NTP treatments resulted in a significant increase in the content of the total aldehydes for milk samples treated for 15 min. Furthermore, the comparison of chromatographic data of control samples with those treated with NTP suggested that the content of total alcohols in the NTP treated samples was slightly higher, while that of the hydrocarbons was not affected by LTP treatment. The molecules significantly affected by NTP treatments included; 2 heptanone, nonanal, 2 octenal, 1 octanol and benzaldyde which showed a marked increase following exposure to the plasma