Abstract
Postharvest storage of many freshly picked berries affects polyphenol and sugar content. However, little is known about the impact of refrigerated and frozen storage on aronia berry composition. Therefore, the objective of this study was to characterize how storage at 4 ± 2 °C and − 20 ± 2 °C, and temperature cycles affect aronia berry polyphenols, total solid content, pH, titratable acidity, polyphenol oxidase (PPO) activity, sugar content, acid content, color, and cell structure. Refrigerated storage reduced proanthocyanidins (21%), anthocyanins (36%), and total phenols (21%) after 12 weeks. Frozen storage increased polyphenols in the first 6 mo. of frozen storage but then decreased polyphenols at mo. 8 to levels similar to initial values. Frozen temperature cycling reduced anthocyanins 18% but did not affect total phenols or proanthocyanidins. Scanning electron microscopy analysis indicated temperature cycling induced cell damage, shrinking, and fusion. This disruption led to the release of anthocyanins inside the berry tissue. PPO activity did not significantly correlate with the decrease in polyphenol content during storage. °Brix did not significantly change during refrigeration and frozen storage but did during the 12th temperature cycle. Aronia berries’ pH and titratable acidity were affected more by refrigeration than frozen and temperature storage. The pH increased by 4% during refrigeration, and titratable acidity decreased by 17% at 12 weeks. In conclusion, refrigerated storage results in a modest reduction of aronia berry polyphenols, but absolute extractable polyphenols are stable for up to 8 months of frozen storage.Graphical abstract
Highlights
Berries have polyphenols and nutrients that promote human health (Diaconeasa 2018)
The results from all the different studies indicate, the rates of change of polyphenols, nutrients, sugars, and acids during storage and temperature depends on the berry type, cultivar, and fruit maturity (Khattab et al 2015; Rickman et al 2007; Šamec & Piljac-Žegarac 2014)
This study evaluates the effects on aronia berries in different storage conditions by examining polyphenols, total solid content, pH, titratable acidity, polyphenol oxidase (PPO), sugar content, acid content, color, and cell structure
Summary
Berries are non-climacteric and harvested at full maturity because they will not continue to ripen (Kahramanoglu 2017). Because they are harvested fully ripened, fresh berries have short shelf lives because of high respiration rates, water loss, and susceptibility toward decay and damage. The results from all the different studies indicate, the rates of change of polyphenols, nutrients, sugars, and acids during storage and temperature depends on the berry type, cultivar, and fruit maturity (Khattab et al 2015; Rickman et al 2007; Šamec & Piljac-Žegarac 2014)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call