Effects of high hydrostatic pressure on physicochemical properties, enzymes activity, and antioxidant capacities of anthocyanins extracts of wild Lonicera caerulea berry

• The stability of cyanidin-3-glucoside was good after HHP processing.
• Two individual anthocyanins were found in wild L. caerulea from China for the first time.
• SOD was not sensitive to high pressure and maintained good stability.
• Low HHP for a long time showed better antioxidant results than high HHP for a short time.
• HHP processing demonstrated better sterilization effect but severely destroyed enzymes.

Wild Lonicera caerulea berries were subjected to five different high hydrostatic pressure (HHP) treatments (which resemble the conditions of active component extraction and commercial sterilization). The content of anthocyanins and total phenolics increased by 6.84% and 14.35% (p < 0.05), respectively after treatment at 200 MPa for 5 and 10 min. As HHP increased, a higher loss of active component was observed. The total phenolic contents did not differ significantly between the control and the 400 MPa/20 min treated group (p > 0.05); HHP processing demonstrated better sterilization effect but severely destroyed enzymes. Polyphenol oxidase (PPO) and peroxidase (POD) activity were activated at lower HHP, such as 200 MPa, and decreased at 400–600 MPa. Superoxide dismutase (SOD) maintained good stability under HHP processing. The antioxidant capacities of anthocyanins extracts of wild L. caerulea berry were evaluated by 3 different methods (DPPH assay, oxygen radical absorbance capacity assay, and cellular antioxidant activity assay).Industrial RelevanceFactors such as color, luster, and nutrition often affect consumer choice in food. However, the color and nutrition of foods tend to be destroyed during processing and storage. The demand for healthier and more nutritious food while retaining the color and flavor after processing highlights the need to develop novel and gentler technologies for fruit processing. Recently, high hydrostatic pressure (HHP) technologies have been used in different branches of the food industry. In the present study, the content of active component in blue honeysuckle fruit pulps such as anthocyanins and polyphenols showed tendency to increase and then decrease with increasing pressure at room temperature. Five different HHP treatment groups (resembling the conditions of active component extraction conditions and commercial sterilization) were compared to the control (fresh fruit) and heat-treated group to determine the effects of HHP processing on L. caerulea berry pulps. The aim of this study was to investigate the changes in active component particularly the content and composition of anthocyanins under different high-pressure treatment at room temperature; the color and physicochemical indexes were also analyzed at the same conditions. Low HHP for a long period of time (400 MPa/20 min) demonstrated better results than that with high HHP for a short time (600 MPa/10 min), as indicated by the higher contents of anthocyanins and phenols and stronger antioxidant capacities. Therefore, Low HHP conditions can be used as an auxiliary means of active component extraction. The conditions of HHP processing at low HHP for a long period of time (400 MPa/20 min) can be altered to retain active components during food processing.