Orange peel essential oil in rice starch encapsulating material for antimicrobial application against Escherichia coli
Felipe Nardo dos Santos; Estefania Júlia Dierings de Souza; Juliani Buchveitz Pires; Rosane Lopes Crizel; Elder Pacheco da Cruz; sabela Schneid Kroning; Laura Martins Fonseca; Leticia Marques de Assis; Graciela Völz Lopes; Alvaro Renato Guerra Dias; Elessandra da Rosa Zavareze
Abstract
This study investigated the formation of fibers and capsules using rice starch as a wall material to encapsulate orange peel essential oil (OPEO) by electrospinning for antimicrobial applications. Rice starch at a concentration of 20 % (w/v) and varying OPEO concentrations (30 %, 40 %, and 50 %, w/w) were used to produce materials. Free OPEO was analyzed for its chemical profile and antimicrobial activity. The electrospun material was characterized for morphology, size distribution, loading capacity, functional groups, thermal properties, and antimicrobial activity against Escherichia coli. Limonene was identified as the main component of OPEO. The free OPEO was effective against E. coli and Salmonella Typhimurium. When different concentrations of OPEO were incorporated into 20 % rice starch solutions, a decrease in electrical conductivity was observed, leading to the formation of fibers and capsules instead of just fibers. The loading capacities of the materials were 35 %, 29 %, and 28 % for OPEO concentrations of 30 %, 40 %, and 50 %, respectively. Encapsulation of OPEO resulted in increased thermal stability. The material with 50 % OPEO achieved a 6-log reduction in E. coli, showing strong potential for active packaging to reduce food contamination. Future research should explore its practical use in food packaging.