Retenção de óleo de café verde em complexos coacervados de proteínas concentradas do soro de leite ou soja e goma arábica

• Ano de defesa: 2014
• Autor(a) principal: Maggioli , Mirtza Fúlvia
• Orientador(a): Cavallieri, Ângelo Luiz Fazani
• Banca de defesa: Cavallieri , Ângelo Luiz Fazani , Gonçalves , Maria Ássima Bittar, Bonsanto, Fabiana Perrechil
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Programa de Pós-graduação em Ciência e Tecnologia de Alimentos (EAEA)
• Departamento: Escola de Agronomia e Engenharia de Alimentos - EAEA (RG)
• País: Brasil
• Palavras-chave em Português: Microencapsulação; Coacervação complexa; Ph; Concentrado proteico do soro de leite / goma arábica; Isolado proteico de soja / goma arábica
• Palavras-chave em Inglês: Microencapsulation; Complex coacervation; Ph; Whey protein / gum arabic; Soy protein / gum arabica
• Área do conhecimento CNPq: CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/6546

This work shows the green coffee oil coacervation processes, as core material, in two different systems: whey protein / gum arabic and soy protein / gum arabic, as biopolymer wall. The biopolymers concentration were fixed in 4% (weight / weight) of the emulsion, and the proportion between then was respectively 2:1 and 1,4:1. Different emulsions were made, each one with a different green coffee oil concentration (0%, 10%, 17.5% and 25%) compared with wall materials. From these emulsions with adjusted pH, the system presented phase separation (coacervation). The following system characteristics were studied: maximum interation pHs, emulsions rheological behavior, emulsions sizes, physico-chemical characterization of the phases (coacervate and supernadant), process mass balance, coacervate rheology, microparticles morphology after lyophilization, the powder density, the powder stability and the microencapsulation process efficiency. The results confirmed that there is an optimum range of particle formation, depending on pH. The emulsions presented typical Newtonian fluid behavior and the viscosity increased with incresing the oil concentration. That behavior does not depend on wall materials. It was also observed that wet coacervates were better fitted to Power Law, presenting pseudoplastic behavior. Concentrate soy protein / gum arabic showed thixotropy. The emulsion gout showed an surface average diameter between 2,24 µm e 14,42µm. The microparticles exhibited slightly spherical, rough surface and pores, probably influenced by drying process. The process efficiency showed no dependence on the oil concentration at studied systems. The adsorption isotherms (at 30°C) of the obtained powders were best fitted to the GAB model and the e moisture content of monolayer (xm) for this model were between 2.5% to 5.1% for CPSL and GA microparticles and between 5.1% and 6.1% for IPS and GA