Radiofrequency cold plasma – A novel tool for flavour modification in fresh and freeze-dried strawberries

Abstract

Cold plasma treatment is an emerging non-thermal food processing tool. This study aimed to identify how cold plasma can improve the aroma of a model space food system (freeze-dried strawberries) by mitigating freeze-drying aroma losses. Cold plasma significantly reduced the negative impact of freeze-drying on aroma; hence, it might be useful as a secondary treatment technique for foods that require extended shelf-life with improved aroma, such as in space travel. “Zero-averaged gravity” (0.004 g), a proxy for non-terrestrial environments, reduced the abundance of two important volatile aroma compounds (methyl butanoate and methyl hexanoate) in the gas phase above strawberries; this loss was mitigated when treated by cold plasma. The impact of cold plasma on aroma was also shown to be matrix and treatment parameter-dependent, and six cold plasma treatment options were subsequently identified as enabling bespoke aroma modifications that ultimately enhanced strawberry aroma compounds.