Reducing water leakage by increasing short-chain fructooligosaccharides in strawberries

Resumen del póster presentado al 55th Annual Meeting of the Society for Cryobiology, celebrado en Madrid (España) del 10 al 13 de julio de 2018.Strawberries, highly appreciated lor their excellent flavor, have relevant economic and nutritional benefits. However, their quality deteriorates rapidly due mainly to water loss. Water is a very important component in fruit, mainly in strawberries that exhibit a large quantity of water. More than moisture content it is of great interest to quantifiy the amount of freezable and unfreezable water fraction in strawberries. Sorne varieties are classified as a high C02 tolerant fruit and atmospheres with high C02 concentrations have been used successfully to control fungal decay and to increase flesh firmness. lnterestingly, the metabolie adjustment caused by high C02 treatment involved the enhancement of hydrophilie compounds, facilitating water retention, thereby improving the quality of chilled and frozen strawberries. The aims of this work were first, to determine how protective short treatment such as 20 kPa C02 for 3 days at low temperature, modities fruit water status. For that, the freezable and unfreezable water content in strawberries from two different harvesting time were studied using differential scanning calorimetry. Second, to analyze how changes in unfreezable water fraction was correlatcd with endogenous fructo-oligosaccharides levels and cell structure in strawberry fruit stored under high C02 atmosphere. Finally, in the prescnt work we also tried to determine whether the changes in the levels of unfreezable water content in C02-treated strawberries might affect the thawing behaviour of fruit tissues. The water-holding capacity of strawberries aller thawing was determined by analysing the drip loss ofC02-treated and untreated samples. Our results suggest that by increasing the concentrations of fructo-oligosaccharides, protective high C02 concentrations reduce the amount of water available to be frozen, thus reducing water leakage associated with the freezing-thawing process.This work was financed by a CICYT Project (AGL2014-50381) from the MICINN (Spain).Peer Reviewe