Effect of pulsed electric fields (PEF) on physico-chemical properties, β-carotene and antioxidant activity of air-dried apricots

• Published in: Food chemistry Vol. 291; pp. 253 - 262
• Main Authors: Huang, Wenshu, Feng, Zuoshan, Aila, Reheman, Hou, Yakun, Carne, Alan, Bekhit, Alaa El-Din Ahmed
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2019
• Subjects: air drying; Air hot drying; Antioxidant activity; Antioxidants - chemistry; Apricot; apricots; beta Carotene - analysis; beta Carotene - chemistry; beta-carotene; catechol oxidase; color; Colour; Desiccation; dried fruit; Electricity; Fruit - chemistry; Fruit - metabolism; heat; heat treatment; peroxidase; polyphenols; Prunus armeniaca - chemistry; Prunus armeniaca - metabolism; Pulsed electric fields; Reactive Oxygen Species - chemistry; sodium sulfite; Sulfur Dioxide - chemistry; Temperature; β-Carotene; Pulsed electric fields; Apricot; Air hot drying; Antioxidant activity; β-Carotene; Colour
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2019.04.021

•The effects of PEF on quality of dried apricot is investigated.•PEF treatments had no effect on the PPO activity and decreased the POD activity by 30% (p < 0.05).•PEF treatments resulted in higher drying rates.•High PEF treatment retained more β-carotene and suffered less browning during air hot drying.•High PEF treatment had higher antioxidant activity and better colour. Fresh apricots pre-treated by pulsed electric fields at different intensities [LPEF, 0.65 kV/cm, 100 Hz, 20 µs and total treatment time 30 s; HPEF1, 1.25 kV/cm, 100 Hz, 20 µs and total treatment time 30 s; HPEF2, 1.25 kV/cm, 100 Hz, 20 µs and total treatment time 60 s], along with controls [non-treated, non-treated and sulphite treated, and heat pre-treatment at 80 °C, for 10 min (HC)] and soaked in 0.2% sodium sulphite solution for 1 h and then were subject to hot air drying. The changes in drying rate, polyphenol oxidase, peroxidase, and β-carotene contents as well as antioxidant activity and colour in pre-treatment and hot air-dried apricot samples were investigated. PEF and heat treatments increased the drying rate of apricots. PEF treatments had no effect on the PPO activity and decreased the POD activity (p < 0.05). HPEF2 treatment retained more β-carotene, higher antioxidant activity and suffered less browning during processing. Overall, the results indicate that combining sulphite treatment with PEF produces dried apricots with more β-carotene and antioxidant activity, and better colour.