CFD model development and validation of a thermonebulisation fungicide fogging system for postharvest storage of fruit

Thermo-Mechanical Analysis in the Fresh Fruit Cold Chain: A Review on Recent Advances

In agro-food research and industry, mathematical models are being used to develop and optimize preharvest and postharvest operations, and their use has grown exponentially over the last decade. Generally, transport phenomena (such as airflow, heat, and mass transfer) during the cooling of horticultural products are complex; therefore, the use of computational modeling techniques is a valid alternative to expensive and difficult experiments because computers continuously become more powerful and less expensive, the software is readily available, and once a model is validated, it is a versatile tool to evaluate the effects of the operating and design parameters involved. In this review, thermo-mechanical modeling studies during postharvest handling are overviewed regarding the experimental, analytical, and computational approaches. The airflow, cooling kinetics, cooling uniformity, and the material and mechanical safety behavior of fresh fruit packaging boxes will be analyzed. Current concerns, challenges, and opportunities are discussed.

Control of Bull's-Eye Rot of Apple Caused by Neofabraea perennans and Neofabraea kienholzii Using Pre- and Postharvest Fungicides

Bull's-eye rot is a major postharvest disease of apple caused by several fungi belonging to the Neofabraea and Phlyctema genera. Chemical control of these fungi is a crucial component of disease management for apples that are conventionally grown. The efficacy of several preharvest and postharvest applied fungicides were evaluated to identify effective chemistries that can control bull's-eye rot incited by Neofabraea perennans and N. kienholzii on apples. In general, the preharvest fungicide thiophanate-methyl was found to be effective at reducing disease caused by N. perennans and N. kienholzii. Two postharvest fungicides, thiabendazole and pyrimethanil, also provided disease control that was far superior to other chemical compounds evaluated in this study. The efficacy of thiabendazole and pyrimethanil was unaffected by application method (fungicide dip compared with thermofog). Despite providing satisfactory control of bull's-eye rot, integration of these three chemicals into disease management programs should proceed judiciously with consideration of their impact on the development of fungicide resistance and influence on diversity in populations of apple postharvest pathogens.

CFD Analysis of Coffee Packaging in Capsules using Gas Flushing Modified Atmosphere Packaging

The aim of this work is to analyze, by means of CFD (Computational Fluid Dynamics), the gas flow in a packaging machine used to fill polymeric capsules with coffee. The final goal is to optimize the geometric shape of some mechanical components in the machine’s sealing station in order to reduce the inert gas consumption achieving an O2 residual which is constantly equal or below 1 % by mass in the center of the capsule. The fluid domain has been obtained starting from the 3D CAD model of the sealing station of the packaging machine. The CAD software SolidWorks has been used to design the system, while Ansys CFX 14.5 software has been used for the CFD analysis. The CFD model has been validated by comparing its results with those obtained by experimental tests. The modified solution allows reducing the average O2 residual from about 3 % to less than 1 %.