Impact of gliding arc plasma pretreatment on drying efficiency and physicochemical properties of grape

• Published in: Innovative food science & emerging technologies 2020-07, Vol.63, p.102381, Article 102381
• Main Authors: Miraei Ashtiani, Seyed-Hassan, Rafiee, Mahta, Mohebi Morad, Mina, Khojastehpour, Mehdi, Khani, Mohammad Reza, Rohani, Abbas, Shokri, Babak, Martynenko, Alex
• Format: Article
• Language: English
• Subjects: Antioxidant activity; Cold plasma; Color; Drying; Microstructure
• ISSN: 1466-8564; 1878-5522
• DOI: 10.1016/j.ifset.2020.102381

The effect of cold plasma pretreatment with different durations 10, 20, 30, 40, 50, and 60 s on the mass transfer rate and quality of grape fruit during hot-air drying at 60 °C and 1.5 m/s were studied. It was found that cold plasma pretreatment significantly increased effective moisture diffusivity, reducing the drying time and energy consumption by up to 26.27% and 26.30%, respectively. Longer exposure resulted in smaller shrinkage and higher rehydration ratio. Furthermore, plasma pretreatment resulted in improved quality of dried grapes, in particular higher total phenolic content, antioxidant activity, and vitamin C retention by up to 3.06–30.53%, 7.31–62.29%, and 17.87–168.73%, as compared to the untreated ones. Among all pretreatments, 50 s exposure was preferred due to the minimal energy consumption and the least effect on the samples color. [Display omitted] •Cold plasma application was tested as a pretreatment to hot-air drying of grapes.•Pretreatment markedly reduced the drying time and energy consumption.•Cold plasma treatment resulted in dried samples with better color.•Pre-treated products absorbed more water during rehydration.•The use of cold plasma decreased TPC, AOA and vitamin C losses in dried grapes.