"After two years of research an impressing comparison was finally drawn - two ounces dried strawberries deliver as many nutritionally valuable substances as 12 ounces frozen strawberries," Dresden's University of Technology stated in a press release. "In other words, two handfuls of dried strawberries are the same as two packages of frozen ones."
The method involves using vacuum microwave puffing technology. Scientists tested the method by processing strawberries as gently as possible to preserve vitamins and secondary plant compounds.
"Examining various processing conditions, the researchers noticed that the food not only kept its valuable substances after drying but it also showed other attractive characteristics such as a crispy texture, stable colour and puffed structure," they stated. "Moreover, the scientists found that the method which was tested for strawberries can be transferred to other kinds of berries, apples and vegetables, too. Therefore, the vacuum microwave puffing technology could soon stand as a new synonym of food preservation."
The method can be used for other kinds of berries, apples and vegetables.
Friedrich-Schiller-Universität Jena carried out a complementary study, examining the impact on those who ate frozen strawberries and those who ate strawberries dried using the technology.
In both cases the anti-oxidative capacity in the blood increased and the immune system was strengthened, which can be explained by the amount of vitamins contained in the strawberries, they found. The benefits equated to two ounces of vacuum microwave puffed strawberries carrying the same nutritional impact as 12 ounces of frozen.
Food companies will have access to the research and technology. Zittauer Fruchtveredlungs, a German company, was involved in the research. The company is currently selling fruit snacks in France that have been processed using the method .
An unnamed German natural product company has expressed its interest in the technology, the scientists reported.