26th September 2012.– European Small and Medium Enterprises (SMEs) dryers will be more competitive thanks to MILD-DRY, a EU-funded project which will deliver an alternative technology for the dehydration of heat sensitive food by combining the benefits of two effective drying methods: microwave and vacuum.
The project consortium will get together on the 27th of September, 2012, for the MILD-DRY kick-off meeting. As the project is coordinated by IRIS Research&Development, the meeting will take place in its branch offices in Dublin (Ireland). The MILD-DRY project consortium is composed of six dried food producers and three research entities, from six different countries across Europe.
The combined MicroWave Vacuum-Drying (MWVD) solution which MILD-DRY will deliver in two years, will offer a rapid and efficient dehydration solution that can yield unique characteristics and improved quality compared to conventionally dried products.
To this end, MILD-DRY will build on the positive results of laboratory trials using microwave-assisted vacuum drying (MAVD) for the successful dehydration of grapes, cranberries, bananas, tomatoes, carrots, garlic, kiwifruit, apple and pear, whereby the drying time for carrots for example was reduced to 2 hours compared with 4.5-8.5 hours in convectional hot air drying. In order to bridge the gap between laboratory research and industrial application, the MILD-DRY project will develop a prototype system for its validation in commercial food drying facilities. The system design will focus on positive economic returns, considering the start-up and maintenance costs, electricity use, ease of operation, and added value to the final products. The MILD-DRY prototype effectiveness will be validated in real commercial food drying facilities. This technology will be affordable, robust and easy to maintain. The treated food will be analysed to ensure its safety and to assess its quality and shelf-life.
The challenge: heat sensitive food
Drying is by far the most useful large scale operation method of keeping solid foods safe for long periods of time. Dried food holds many advantages for the mass production of commercially prepared goods, not least cheaper transportation costs, longer storage life and ease of use. However, heat sensitive foods and products that possess excellent quality in terms of taste, aroma, texture, and appearance, pose a major challenge to driers. Products like herbs, spices, seafood, garlic, ginger, spring onions and shrimps are cellular tissues containing gas-filled pores that tend to collapse when subjected to dehydration. This collapse is more noticeable with prolonged exposure to elevated drying temperatures, such as those used in convective drying. For this reason, hot air drying results in substantial degradation in quality attributes such as colour, nutrients and flavour, sever shrinkage also reduces bulk density and dehydration capacity. Also, chemical changes causing loss of flavour and nutrients occur during convective drying so the properties of dehydrated products are poor.
Meeting today´s driers needs
A number of drying techniques have been developed over the years, among them atmospheric forced-air dehydration, which is a very common method. The major disadvantage of the hot air convective drying of food is the low energy efficiency and lengthy drying time during the falling rate period.
While one effective alternative is 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. Moreover, in view of the high capital costs involved AFD is often prohibitive for SMEs.
There is thus a clear need to provide companies 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, paving the way forward for multinationals and low cost manufacturers from Third countries to gain an increasing foothold in the marketplace. Drying operations need to be precisely controlled and optimized in order to produce a good quality product that has the highest level of nutrient retention and flavor whilst maintaining microbial safety.
The R&D project coordinator Dr Adriana Delgado, from IRIS, highlights the potential of the MILD-DRY: “Advantages of these two effective drying methods, microwave drying (MW), in particular variable frequency microwave heating, and vacuum drying (VD), will be combined to take the most of each techniques: cost and speed in the case of MW and quality preservation in the case of VD.”. Dr Delgado stresses that “the European SME driers will be provided with an affordable drying method which will overcome cost limitations that SMEs cannot afford to operate, like the AFD”.
Besides IRIS, the other eight companies and entities involved in the European project are as follows: University College Dublin, National University of Ireland Dublin; Lebensmittelversuchsanstalt, Austria; Fullwell Mill Limited, United Kingdom; Tuerkiye Suet Et Gida Sanayicileri Ve Uereticileri Birligi Dernegi, Turkey; Freshseal Limited, United Kingdom; Gokser Makina Sanayi Ve Ticaret Limited Sirketi, Turkey; Evaluation Technologique Ingenieurie et Applications SA (ETIA), France; and The Food Machinery Company, United Kingdom.
Dissemination Manager - Melek Us, Setbir, Turkey.
Intellectual Property Manager - Lee Gapper, The Food Machinery Company, United Kingdom.
To learn more about the MILD-DRY project, please visit www.milddry.eu. The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) managed by REA Research Executive Agency under grant agreement n° 315043.