Juice related water-soluble pectin characteristics and bioaccessibility of bioactive compounds in oil and emulsion incorporated mixed juice processed by high pressure homogenization

Abstract

Aim of this study was to investigate the juice related water-soluble pectin (WSP) characteristics, total carotenoid bioaccessibility (TCB) and total polyphenolic bioaccessibility (TPB) in oil and emulsion incorporated high pressure homogenized mixed juices. Five mixed juices were prepared with carrot puree, clear apple juice and peach juice at ratios of 50:30:20, 40:40:20, 30:50:20, 40:30:30 and 30:40:30, and subjected to homogenization at 140 MPa and 25 °C for 1 pass. Galacturonic acid (GalA) content, degree of methylesterification (DM), neutral sugars and molecular weight (Mw) were analyzed. Bioaccessibility of carotenoids and polyphenolics was evaluated by using either corn oil or corn oil emulsion. As the results indicated, distinct particle and WSP characteristics were observed among different juice ratios of homogenized mixed juices. Small intestinal digesta showed varied particle and rheological properties. Besides, TCB was significantly higher when added with oil or emulsion than no oil added. Nevertheless, the ratio at 30:40:30 of carrot, apple and peach exhibited the highest TCB, WSP content and DM value, while the ratio at 30:50:20 showed the highest TPB. Results highlighted the potential of manipulating juice ratio to enhance TCB and TPB. Moreover, bioaccessibility of bioactive compounds exhibited significant correlations with particle properties and WSP characteristics respectively. TCB showed upward polynomial correlations with volume-mean and area-mean diameters of digesta respectively, while exhibited downward polynomial correlations with WSP content and DM, respectively. Meanwhile, TPB showed upward polynomial correlations with WSP content and DM, respectively.