Model food for microwave-assisted pasteurization of fruit juices and nectars at 915 and 2,450 MHz

Author(s)

Sobreiro, Pedro Henrique ^[1] ; Isozaki Sato, Laura Naomi ^[1] ; Wilhelms Gut, Jorge Andrey ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Dept Chem Engn, Escola Politecn, BR-05508010 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, FoRC Food Res Ctr, Sao Paulo - Brazil

• Document type: Journal article
• Source: JOURNAL OF FOOD PROCESS ENGINEERING; v. 41, n. 7 NOV 2018.
• Web of Science Citations: 0

Abstract

A model food based on aqueous solutions of sucrose and sodium chloride is proposed for studying the microwave-assisted pasteurization of fruit juices and nectars. Relative electrical permittivity, dielectric loss factor, and electrical conductivity of solutions with sucrose up to 40.0 g/100 mL and sodium chloride up to 1.6 g/100 mL were experimentally determined and successfully correlated with concentrations and temperature (from 10 to 90 degrees C). By adjusting the concentrations of the solutes, it was possible to satisfactorily match the dielectric behavior of 12 examples of products. Thermophysical and flow properties of the model food (density, specific heat, thermal conductivity, and viscosity) could be estimated from literature data, which is useful for process simulation. Continuous flow microwave heating is an emerging technology with a potential to be used in the thermal processing of liquid foods. Model foods are important to study heating patterns, test prototypes, test process control, or tuning strategies, to be used as sterilization solutions, or carrier of chemical, biological, or enzymatic markers. The model food proposed here can match dielectric properties of fruit juices or nectars. (AU)

• FAPESP's process: 14/17534-0 - Evaluation of the effects of focused microwave processing on liquid foods
• Grantee: Jorge Andrey Wilhelms Gut
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07914-8 - FoRC - Food Research Center
• Grantee: Bernadette Dora Gombossy de Melo Franco
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 12/04073-0 - Experimental determination of the dielectric properties of liquid and pasty foods considering the continuous heat treatment using microwave technology
• Grantee: Carmen Cecilia Tadini
• Support Opportunities: Regular Research Grants