New philosophy for drying mangoes
In a revolutionary approach towards drying mangoes, Munters South Africa and Landman Dried Produce embarked on a journey of research and proved a new drying method that is conceptually and thermodynamically ground-breaking in the fruit-drying industry. Landman Dried Produce has been exporting fresh mangoes to Europe for many years prior to embarking on drying their mangoes for export. Munters and Landman Dried Produce got together with the mutual goal of setting a new standard in quality dried mango.
Hygiene is more easily controlled in Munters “enclosed-loop” system, as if all care is taken with hygiene from the beginning of the process, there is a low risk of yeast formation in this type of system. This is because the air is recirculated and reconditioned without the possibility of being contaminated with unnecessary fresh air.
Munters approach optimizes the energy-efficiency in two areas of temperature and enthalpy. Munters provides the right balance of dry air to temperature. Because the drying chamber removes moisture from the fruit, the air needs to be conditioned to create the right climate condition for the fruit to relinquish its moisture efficiently and naturally. Within all markets Munters objective is to find the most energy-efficient method. Munters method utilizes 40% less energy consumption than envisaged by the producer, which has helped alleviate heavier electrical infrastructure costs and assisted with the reduction of on-demand consumption of electricity.
Landman Dried Produce has had very positive feedback from their international clientele and SAD asserted that the new approach produces superlative quality for the export market. While the mango-drying season typically ends mid-April, Landman Dried Produce can now continue throughout the year, drying other fruits such as banana and papaya, where the results have also been more than satisfactory. Munters, through their sixty-year excellence in drying technology, continue to serve the food industry through their development of innovative solutions.
Munters supplied an enhanced MX7600 system solution to supply low humidity air through a tunnel holding wet mango layered out on trays. 7500kg of wet Mango were batch dried to 1500kg in 30 hours. The layers were created to maximise air distribution over the mangoes for maximum evaporative effect. Through careful trial, Munters found an optimized three-step humidity approach suitable for the varying conditions required during the drying process. Temperature and humidity is kept constant in the re-circulated air and care is taken not to surface dry the product. The evaporative effect is extremely strong in the first step of the drying cycle, so Munters create the optimum humidity level whilst maintaining the supply air at 35oC.
This new drying process is revolutionary because at no stage is the fruit warmer than 36oC. This has a major impact on quality, as too much heat affects both colour and taste. With this new Munters approach, colour retention is extremely good and taste more natural, with improvements in the dried product’s texture too.