Evaluation of the anthocyanin release and health-promoting properties of Pinot Noir grape juices after pulsed electric fields

• Published in: Food chemistry 2016-04, Vol.196, p.833-841
• Main Authors: Leong, Sze Ying, Burritt, David John, Oey, Indrawati
• Format: Article
• Language: English
• Subjects: Anthocyanins; Anthocyanins - chemistry; Antioxidant activity; Antioxidants; Caco-2 cells; Caco-2 Cells - chemistry; Electromagnetic Fields; Fruit - chemistry; Humans; Maceration; Oxidative Stress; Phenols - analysis; Phenols - chemistry; Pinot Noir; Pulsed electric fields; Vitis - chemistry
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2015.10.025

•PEF accelerated the release of grape anthocyanins.•PEF improved the bioprotective capacity of grape juice.•The ability of grape juice in protecting Caco-2 cells against oxidative stress was evaluated.•Results from Caco-2 cells assay highly correlated with anthocyanins. This study evaluated the health-promoting properties of Pinot Noir juices (Vitis vinifera L.) obtained at different maceration times after pulsed electric fields (PEF) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and human intestinal Caco-2 cells assays. Juice quality, anthocyanins, total phenolics and vitamin C were also determined. The evaluation of bioprotective capacity of the juice against H2O2-induced oxidative stress in Caco-2 cells was determined using biomarkers for cellular health and integrity: cell viability and lactate dehydrogenase (LDH) leakage. Compared to untreated grape juice, PEF pre-treatment on grapes enhanced the release of the major anthocyanin found in Pinot Noir, i.e. malvidin-3-O-glucoside (+224%). Increase in the content of total phenolic (+61%) and vitamin C (+19%) as well as improvement in the DPPH scavenging activity (+31%) and bioprotective capacity (+25% for cell viability and +30% for LDH leakage) were observed in grape juices following PEF treatment. Bioprotective capacity determined by the cellular biomarkers had significant linear correlations with malvidin-3-O-glucoside content (0.71⩽r⩽0.73) whereas DPPH scavenging activity was not well correlated with malvidin-3-O-glucoside (r=0.30) and total phenolics (r=0.30). Therefore, evaluation of the bioprotective capacities using Caco-2 cell assay performed in this study makes a novel contribution to the current knowledge that demonstrates the capability of PEF technology to produce plant-based foods with better phytochemical composition and exhibiting the capacity to protect cells from oxidative stress.