Study of enzyme inactivation in the processing of green coconut water by focused microwave technology

• Grant number: 14/25179-6
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2015
• Effective date (End): February 28, 2017
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Engineering
• Acordo de Cooperação: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Jorge Andrey Wilhelms Gut
• Grantee: Eduardo dos Santos Funcia
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 13/07914-8 - FoRC - Food Research Center, AP.CEPID

Abstract

In the processing of liquid foods, continuous heat treatment is intended for inactivating microorganisms and enzymes that compromise the safety and product quality. In the case of green coconut water, enzymes polyphenoloxidase (PPO) and peroxidase (POD) exhibit high thermal stability and the sensorial quality of the product (color and taste) is sensitive to high temperatures, making it challenging to process this product without the addition of preservatives. The emerging technology of continuous heating by focused microwaves is promising for promoting rapid volumetric heating without surface overheating and with a non-thermal effect on enzyme inactivation. Thus, the objective of this work is to study the inactivation of PPO and POD in green coconut water to determine the respective kinetics in conventional and microwave heating, seeking identification of non-thermal effects, with validation of the obtained conditions in a pilot scale equipment. To study the kinetics, batch tests will be performed in immersion thermal baths and in a chemical synthesis mini-reactor by focused microwaves with fiber optic temperature record. The enzymatic activity will be evaluated by spectrophotometric methods. Kinetic models for prediction of residual activity will be adjusted based on recorded temperature history using a non-linear optimization method linked to the numerical integration of lethality, thus avoiding the simplifying assumption of constant temperature. Based on the results of the batch runs, processing conditions compatible with the pilot scale equipment with heating by focused microwaves will be defined and tested for obtaining an adequate level of residual enzymatic activity. It is expected that this research will allow the elucidation of the non-thermal effects of microwaves on the inactivation of the enzymes of green coconut water and assessing the feasibility of innovative technology for the processing of this product. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SIGUEMOTO, ERICA SAYURI; PIRES, MARCOS NEVES; FUNCIA, EDUARDO DOS SANTOS; WILHELMS GUT, JORGE ANDREY. Evaluation and modeling of a microwave-assisted unit for continuous flow pasteurization of liquid foods: Residence time distribution, time-temperature history, and integrated lethality. JOURNAL OF FOOD PROCESS ENGINEERING, v. 41, n. 8, DEC 2018. (16/24265-1, 14/06026-4, 15/20113-0, 14/25179-6, 13/07914-8)

FUNCIA, EDUARDO S.; GUT, JORGE A. W.; SASTRY, SUDHIR K.. Effect of Electric Field on Pectinesterase Inactivation During Orange Juice Pasteurization by Ohmic Heating. Food and Bioprocess Technology, v. 13, n. 7, JUN 2020. (16/24265-1, 14/17534-0, 17/24163-7, 13/07914-8, 14/25179-6)

BULHOES BEZERRA CAVALCANTE, TIAGO AUGUSTO; FUNCIA, EDUARDO DOS SANTOS; WILHELMS GUT, JORGE ANDREY. Inactivation of polyphenol oxidase by microwave and conventional heating: Investigation of thermal and non-thermal effects of focused microwaves. Food Chemistry, v. 340, MAR 15 2021. (16/24265-1, 14/17534-0, 14/25041-4, 13/07914-8, 14/25179-6)

SIGUEMOTO, ERICA SAYURI; FUNCIA, EDUARDO DOS SANTOS; PIRES, MARCOS NEVES; WILHELMS GUT, JORGE ANDREY. Modeling of time-temperature history and enzymatic inactivation of cloudy apple juice in continuous flow microwave assisted pasteurization. FOOD AND BIOPRODUCTS PROCESSING, v. 111, p. 45-53, SEP 2018. (16/24265-1, 14/06026-4, 15/20113-0, 14/25179-6, 13/07914-8)

ROJAS, MELIZA LINDSAY; TREVILIN, JULIA HELLMEISTER; FUNCIA, EDUARDO DOS SANTOS; WILHELMS GUT, JORGE ANDREY; DUARTE AUGUSTO, PEDRO ESTEVES. Using ultrasound technology for the inactivation and thermal sensitization of peroxidase in green coconut water. ULTRASONICS SONOCHEMISTRY, v. 36, p. 173-181, MAY 2017. (14/16998-3, 14/25179-6, 14/17534-0)