# Postharvest Evaluations of Blackcurrant Fruits with Chitosan and Ultraviolet A Treatments
## 4 Conclusions  
Blackcurrants are well known for their health benefits and are consumed in different forms (fresh, as juices, and in other products), but no research has been performed on blackcurrant postharvest storage combined with chitosan and lights. This research offers researchers and fruit processors a general knowledge of the applications of chitosan and UVA light-separated and combined treatments through multiple fruit quality analyses.  
The results indicated that the treatment influenced berry sugar content without influencing the pH and acids. Chitosan reduced the weight loss compared with the control treatment. UVA increased the weight loss during blackcurrant postharvest storage. Chitosan had effects on microbial populations with or without UVA. UVA, on the other hand, had few antimicrobial effects during blackcurrant postharvest storage. Antioxidants and antioxidant activity assays indicated that in general, treatments did not make significant differences on both total antioxidants and antioxidant activities; changes mainly came from storage time ranges. Specifically, the treatments did have significant effects on certain monomeric phenolics, including cyanidin-3-galactosidase, rutin, luteolin, isorhametin, and kaempfer. Among these substrates, UVA largely influenced cyanidin-3-galactosidase and rutin. Chitosan influenced luteolin content in blackcurrant fruits after storage. In conclusion, chitosan and UVA had differential effects on blackcurrant postharvest storage. Chitosan positively influenced the controlling of weight loss and microbial population growth during postharvest storage, whereas UVA enhanced certain anthocyanin substances.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app142412052/s1](https://www.mdpi.com/article/10.3390/app142412052/s1)]([https://www.mdpi.com/article/10.3390/app142412052/s1](https://www.mdpi.com/article/10.3390/app142412052/s1)), Table S1: Standards in Ultra High-Performance Liquid Chromatography (UHPLC). Table S2: Ascorbic acid content under postharvest treatments. Table S3: Total antioxidant capacities of blackcurrants during storage.  
Conceptualization, Z.W.; methodology, Z.W. and A.S.; investigation, Z.W., A.S., Z.M. and A.A.W.; formal analysis, Z.W., A.S. and Z.M.; fruit collection, Z.M., A.S. and V.R.K.; writing--original draft, Z.W.; writing--review and editing, Z.W., A.S., Z.M., A.A.W. and V.R.K.;funding acquisition, Z.W., A.S. and Z.M. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Specialty Crop Block Grant Program, Grant No. AM22 SCBPMT1127.  
Not applicable.  
The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.  
The authors would like to thank farm manager [PERSON] and the 2022 summer crew for assistance with farm maintenance. The authors would also like to thank research associate [PERSON] and administrative associate [PERSON] for the work coordination.  
The authors declare no conflicts of interest.