Freeze-drying can be just as effective at preserving nutrients in fruit as freezing, according to new research.
The study was carried out by freeze dried ingredients supplier Chaucer, with Newcastle University’s School of Agriculture, Food and Rural Development. The researchers tested the levels of two nutrients – vitamin C and anthocyanins – in freeze-dried strawberries over a 12-month period, comparing them with frozen strawberries kept for the same period of time.
They found no major difference in the nutritional stability of the two sets of samples. The freeze-dried fruit lost on average 1.8% of its vitamin C and 1.4% of its anthocyanin for each month of the trial, while the frozen lost 1.4% of its vitamin C and 2.3% of its anthocyanin.
The findings back up those of a 2013 study carried out by Chaucer with Sheffield Hallam University, which looked at a number of fruits and vegetables. That study found that freeze-drying had little detrimental effect on the vitamin C content, total antioxidant capacity or total phenolic content of either strawberries or the other plants tested.
“Vitamin C and anthocyanin are key nutritional markers for the overall nutrient content of foods,” said Chaucer CEO Andy Ducker, “but their sensitivity to heat, light and oxygen mean that they can be partially or completely destroyed by long storage periods.
“Given the increasing demand for healthy alternatives to processed ingredients we continue to invest in studies and technologies to improve our understanding and capabilities, ultimately responding to consumers’ needs.”
As well as supplying ingredients to manufacturers including Kellogg’s, Mondelez International, Unilever and Nestlé, Chaucer makes freeze-dried fruit and veg snacks under the Fru Snax and Nothing But brand names – the latter of which has recently gained listings in Holland & Barrett and Whole Foods Marke