Color stability and anthocyanins retention in microwave‐thermally treated rose powder extracts during storage

Foods rich in anthocyanins are thermally treated to ensure their safety and are stored for a period of time before consumption. Thermal pretreatment could enhance the color and stability of anthocyanins content in most food products. The combination of thermal treatment and storage under subsequent conditions had a significant effect on anthocyanins. The rose powder dispersed in water, aqueous ethanol, and acidified methanol solutions is thermally processed by microwave heating at 400, 600, and 800 W. The extraction rate and stability of anthocyanins and color of the samples during storage at 4°C, 27°C, and 37°C were investigated. Color parameters were monitored using a colorimeter and the stability of anthocyanins was determined by a UV spectrophotometer. Anthocyanins degradation in the microwave thermally treated rose powder solutions after storage at 37°C was faster than those stored under 4°C and 27°C. The storage temperature 4°C resulted in an excellent color and anthocyanins stability. The methanol extracted rose powder solutions resulted in the lowest loss of anthocyanins content in all storage temperatures and times. Practical applications This study investigated the effect of extracted solutions combined with thermal treatments on the color and anthocyanins stability of the rose powder. The results showed the advances in storage time and 4°C storage temperature on the color and anthocyanins content.