Evaluation of freeze drying combined with microwave vacuum drying for functional okra snacks: Antioxidant properties, sensory quality, and energy consumption. (1st September 2017)

• Record Type: Journal Article
• Authors: Jiang, Ning; Liu, Chunquan; Li, Dajing; Zhang, Zhongyuan; Liu, Chunju; Wang, Di; Niu, Liying; Zhang, Min
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 82(2017)
• Page Start: 216
• Page End: 226
• Publication Date: 2017-09-01
• Subjects: FD-MVD -- Quercetin -- Epigallocatechin -- Antioxidant activity -- Functional okra snacks; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2017.04.015
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: This study evaluated freeze drying combined with microwave vacuum drying (FD-MVD) for functional okra snacks. FD-MVD was compared using four different drying methods: hot air drying (AD), freeze drying (FD), microwave vacuum drying (MVD), and hot air drying combined with microwave vacuum drying (AD-MVD). For main antioxidant components including epigallocatechin gallate (EGC), epicatechin gallate (EGCG), epigallocatechin (ECG), quercetin 3- O -diglucoside, and quercetin 3- O -(malonyl) and antioxidant properties (IC50, AEAC, FRAP, ABTS, TF, and TPC) and color ( L*, a*, and b* ), the values of FD-MVD were similar to those of FD and significantly higher than those of AD, MVD, and AD-MVD ( P < 0.05). Compared to FD, FD-MVD provided moderate hardness (22.43 ± 1.18 N) and crispness (6.74 ± 0.87 N), and reduced the drying time and energy consumption by approximately 75.36% and 71.92%, respectively. Principal component analysis (PCA) of physicochemical and drying efficiency indexes indicated that FD-MVD is a promising technique for the processing of functional okra snacks. Highlights: The main quercetin and epigallocatechin in okra fruit were identified and quantified. FD-MVD was first applied in functional okra snacks. Comprehensive evaluation of quality and energy consumption was built by PCA. FD-MVD is very promising for functional okra snacks in good quality and cost saving.