Low grade grapes and red pepper were obtained from local market. The material was collected immediately prior to the disposal step, blended and homogenized by using Sonicator (Ultrasonic processor) XL No. 2015 10 in dark place, then placed in petri dish, packed with aluminium foil and stored in a refrigerator at 50°C.
All samples were freeze dried (LABCONCO, Kansas City, USA) at 50 °C & 0.014 mbar
for 2 days to reach moisture content 4 %. Grapes and pepper samples powder were
ground and stored in a refrigerator at 80 °C in brown glass bottle to prevent oxidative
damage until extractionred materials, and several capsaicinoids.