Enhancing carrot convective drying combining ethanol and ultrasound as pre-treatments: effect on product structure, quality, energy consumption, drying and rehydration kinetics

• Ano de defesa: 2021
• Autor(a) principal: Santos, Karoline Costa dos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Convective drying; Etanol; Ethanol; Rehydration; Reidratação; Secagem convectiva; Ultrasound; Ultrassom
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/11/11141/tde-27052021-143809/

This work evaluated pre-treatments with ethanol and/or ultrasound to the convective drying of carrots, also evaluating structural changes, technological and nutritional quality parameters and describing the involved mechanisms. The pre-treatments with ethanol and ethanol+ultrasound modified both carrot microstructure (cell wall modifications of parenchymatic tissue) and macrostructure (shrinkage and resistance to perforation). Differently, ultrasound in water resulted in cellular swelling and texture behaviour similar to the control. After drying, no differences in shrinkage ratio were observed in all treatments. However, pre-treatments with ethanol and ethanol+ultrasound improved the drying kinetics, reducing the processing time (∼50%) and the energy consumption (42- 62%). These pre-treatments also enhanced rehydration, whose initial rate and water retention were higher than the control. In addition, the carotenoid content was preserved after drying, for all the treatments. Therefore, this study describe an alternative to increase the production of stable foods with improved drying and rehydration processes, without compromising quality.