High-pressure processing, microwave, ohmic, and conventional thermal pasteurization: Quality aspects and energy economics

© 2019 The Authors. Journal of Food Process Engineering published by Wiley Periodicals, Inc. In this work, we collect and compare product quality data (vitamin C and flavor compounds) for orange juice processed using conventional thermal and innovative (high pressure, microwave, and ohmic) technologies under commercially representative conditions. We also measure and compare their respective energy demands and associated costs. While significant efficiency gains are made due to electrification using the innovative technologies (especially the ohmic process), the high per-unit costs of grid electricity results in poorer processing economics relative to conventional gas-fired technologies. UK levelized cost of electricity (LCOE) data suggest that as the share of renewables in the electricity generation energy mix is increased, the innovative technologies will eventually become more economical, in addition to the significant greenhouse gas emission reductions per liter of product. No significant differences are observed in the quality attributes of the processed product across all the technologies. The innovative electricity-driven technologies are thus promising alternatives to conventional thermal pasteurization. Practical applications: Beverage processing by conventional thermal treatment is energy consuming and can adversely affect the sensory and nutritional quality attributes of the final product. Innovative, mild processing techniques such as high-pressure processing, microwave, and ohmic heating are increasingly gaining industry attention due to their potentials to significantly address these challenges. Actual uptake is still relatively low due to factors including risk aversion, process validation issues, and economics. This work compares these technologies with conventional thermal treatment in terms of critical product quality attributes (vitamin C and flavor compounds) and process energy economics under commercially representative processing conditions. The results of this study will be useful as a guide to food processors for implementing the innovative technologies and could lead to new product development and process optimization.Research Councils UK. Grant Number: EP/K011820/

Reducing energy consumption in spray drying by monodisperse droplet generation: Modelling and simulation

The possibilities of reducing energy consumption in spray drying by monodisperse droplet generation have been explored. From heat/mass balances and droplet travel dynamics in a single-stream spray dryer, correlations have been established for the drying gas temperatures that satisfy given outlet product moisture contents for droplet streams of different diameters-with skimmed milk as a case study. The results suggest that energy consumption can be reduced by up to 90%, compared to what obtains in a conventional system that produces droplet sizes up to 10 times the desired size. An experimental single-stream monodisperse droplet dryer, based on piezoelectric atomisation has been constructed, with an imaging system for future validation studies

Energy and quality performance assessment of emerging and conventional food preservation technologies

This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) The energy performance of emerging food pasteurisation technologies (high pressure processing, microwave volumetric heating, ohmic heating) are evaluated to establish whether they can offer significant reductions in energy consumption and overall carbon emissions, relative to conventional processes, while delivering equivalent microbiological lethality, nutritional and organoleptic quality under commercially-representative processing conditions. Product quality (vitamin C and flavour compounds) data have been collected using established analytical and instrumental methods to benchmark achievable product quality improvements. The results show that for maintaining the raw product quality, the emerging electro-technologies are more energy- and primary resource-efficient, subject to identified operating parameters.Research Councils UK (RCUK

Comparative assessment of innovative and conventional food preservation technologies: Process energy performance and greenhouse gas emissions

Research Councils U