EFFECT OF PLASMA ENERGY ON THE ANTIOXIDANT ACTIVITY, TOTAL POLYPHENOLS AND FUNGAL VIABILITY IN CHAMOMILE (MATRICARIA CHAMOMILLA) AND CINNAMON (CINNAMOMUM ZEYLANICUM)

Abstract

The plasma energy is a collection of free particles with positive and negative charges and has demonstrated to be a good prospect for food preservation. The aim of this study was to evaluate the effect of plasma energy on the antioxidant activity, total polyphenol content and yeasts and molds counts in chamomile and cinnamon powder samples treated at 650, 750 and 850 volts for 0, 1, 3 ,5 7 and10 min. Total counts of yeasts and molds in chamomile and cinamon powder samples were determined before and after each treatment with plasma energy. The enumeration was conducted on potatoe dextrose agar suplemented with 0.6% Bengal rose and 2% ampicillin. The antioxidant activity and total polyphenol content were also analyzed. The results showed that plasma exposure on chamomile and cinnamon powder at 850V for 10 minutes significantly reduced (p<0.05) the concentration of yeasts and molds reduced to <1.0 log CFU/g, and only 0.68±0.19 log CFU/g, respectively. Regarding the antioxidant activity and the total polyphenol content, we observed a reduction of 55% in the antioxidant activity in chamomile, while in cinnamon; there was an increase of 21.4% at 750 V. The highest total polyphenol content was observed after 10 min of treatment at 650 V and 750V, with concentrations of 3.3 ± 0.05 mg GAE/g in chamomile and 1.7 ± 0.01 mg GAE/g in cinnamon. We conclude that treatment with plasma at 750 Volts and 10 minutes of exposure was the best treatment to significantly reduce (p<0.05) yeasts and molds counts without affecting the total polyphenol content in chamomile and cinnamon powder.