Secagem da madeira de louro preto (Nectandra cuspidata) em estufa de micro-ondas

Microwave drying will play an important role in the industrialization of timber in the near future, because improved dimensional stability and increased mechanical strength of wood are dependent on its drying. The objective of this study was to evaluate the drying of Louro preto wood using the microwave process and its influence on drying time, final moisture content, and formation of checks. A program originally developed for Mahogany wood was used due to the similarity between the basic density values of the two wood species. To this end, three (3) drying processes were conducted: drying S1, with initial average moisture content above the fiber saturation point (FSP), reached 13.99% of the final average moisture content after 2h 25min; whereas drying S2 and S3, with initial average moisture contents below the FSP, showed 14.00 and 14.62% of the final average moisture content after 2h 8min and 2h 2min, respectively. The drying processes were considered fast, and the difference in the initial moisture contents of the samples showed the influence of the treatments in the formation of end and surface checks. Drying S2 was more prone to present surface checks than end checks, whereas internal checks were not found in any of the drying processes performed

Unlocking Potentials of Microwaves for Food Safety and Quality

Abstract: Microwave is an effective means to deliver energy to food through polymeric package materials, offering potential for developing short-time in-package sterilization and pasteurization processes. The complex physics related to microwave propagation and microwave heating require special attention to the design of process systems and development of thermal processes in compliance with regulatory requirements for food safety. This article describes the basic microwave properties relevant to heating uniformity and system design, and provides a historical overview on the development of microwave-assisted thermal sterilization (MATS) and pasteurization systems in research laboratories and used in food plants. It presents recent activities on the development of 915 MHz single-mode MATS technology, the procedures leading to regulatory acceptance, and sensory results of the processed products. The article discusses needs for further efforts to bridge remaining knowledge gaps and facilitate transfer of academic research to industrial implementation