An EU funded project is aiming to deliver an alternative technology for the dehydration of heat sensitive food through variable frequency microwave and vacuum drying.
MILD-DRY, headed by Spain-based research firm, IRIS, is composed of nine partners from five countries and plans to deliver a combined MicroWave Vacuum drying (MWVD) solution within two years.
The solution will offer a rapid and efficient dehydration method that can yield unique characteristics and improved quality compared to conventionally dried products, said IRIS.
The project will develop a prototype system for its validation in commercial food drying facilities and prototype effectiveness will be validated in commercial food drying facilities.
IRIS said there is a clear need to provide SMEs involved in food dehydration with a technology which will help to overcome the limitations that are currently squeezing European SMEs out of the food drying sector.
Dr Adriana Delgado, project manager, told FoodProductionDaily.com industrial microwave food processing is mostly based on single frequency microwave sources.
“It is expected that the SMEs will use, at the end of the project, the foreground of this research and development work, and exploit them, since they have full ownership of these results.
“That is, during the two years project, research will be steered towards ensuring that the variable frequency MWVD system is scalable and versatile, economical to run and that it makes a significant improvement on the existing commercial drying methods.
“Then, after completion of the project, the SMEs can carry out further research so as to arrive at a fully industrial product, which they will be able to bring to the market in order to realise the beneficial impacts of this research.”
The project will build on laboratory trials using microwave-assisted vacuum drying for the successful dehydration of cranberries, bananas, tomatoes, carrots, garlic, apple and pear. One experiment showed the drying time for carrots was reduced to two hours compared with 4.5-8.5 hours in convectional hot air drying.
She added that MILD-DRY would enable SMEs to save time, money and safeguard their end products.
“This will enable them to maintain their market share in the face of low cost competition from Third Countries, as well as to be better able to compete in the global marketplace.
“The project also represents a business opportunity for the various SMEs suppliers or manufacturers of equipment as it will result in increased sales of components and equipment to produce the system, as well as revenue that will be generated through the installation and servicing of the system.”
Atmospheric forced-air dehydration occurs when the hot air convective dryingof food but has low energy efficiency and lengthy drying time during the falling rate period.
Accelerated Freeze Drying (AFD), which is less damaging to food than conventional hot air drying, it proves expensive, and is a time and energy intensive operation that can only be economically applied to products of a high market value.
Delgado added there are drawbacks to current methods such as non-uniform energy distribution, hot spots and thermal runaway that have been related to single frequency microwave sources.