Microencapsulation of walnut, peanut and pecan oils by spray drying

Publication date: Available online 20 April 2017 Source:Food Structure Author(s): J.J. Luna-Guevara, C.E. Ochoa-Velasco, P. Hernández-Carranza, J.A. Guerrero-Beltrán The aim of this study was to evaluate some physicochemical (peroxide index, water activity), antioxidant (DPPH method), and morphological (electron microscopy) characteristics of microencapsulated oils of walnuts (Juglans regia L.), peanuts (Arachis hypogaea), and pecans (Carya illinoinensis (Wangenh.) K. Koch) obtained by spray-drying. Emulsions with two concentrations of nuts oils (1 and 3%) were prepared with gum Arabic (3.1%), maltodextrin (4.7%), and gelatin (2.2%). The inlet and outlet temperatures in the drying system were 180 and 84°C, respectively; the feeding flow rate of emulsions was 17mL/min. Powders were stored for 28 days at room temperature. During storage, the peroxide index (PI) increased from 0.99 to 2.84-2.97 meq/kg in all types of nuts microencapsulates regardless the amount of oil used. Water activity was lower in microencapsulates from emulsion with 1% oil. The antioxidant capacity (AC) of microencapsulates was below that found in fresh oils. However, it was observed that the AC was slightly higher in microencapsulates from emulsion with 3% oil (51.4-60.3mg of Trolox/g) compared to those from 1% oil (46.5-49.30mg of Trolox/g). During storage, the antioxidant capacity increased from 21.3 to 33.3% in microencapsulates from emulsion with 3% oil. Microencapsulates from emulsion with 3%...
Source: Food Structure - Category: Food Science Source Type: research