Performance evaluation of different grown ber (Ziziphus mauritiana) cultivars under low-temperature storage

Abstract

ABSTRACT Ber (Ziziphus mauritiana), also known as “Chinese date” or “jujube,” belongs to the Rhamnaceae family. The current research was designed to assess the effect of storage temperatures (5°C and 15°C) on ascorbic acid content, reducing sugar content, and titratable acidity of four ber (Z. mauritiana) varieties, i.e. Karela, Aakash, Pak white, and Dil-Bahar. For this purpose, fresh ber (Z. mauritiana) varieties were acquired from the Regional Agriculture Research Institute (RARI), Bahawalpur. In the first phase, these ber (Z. mauritiana) varieties were subjected to proximate analysis of reducing sugar contents, titratable acidity, antioxidant activity, and total phenolic contents. Maximum total phenolic content (144.38 ± 0.03 mgGAE/100 g) and antioxidant activity (39 ± 0.06%) were observed in Dil-Bahar variety. In the second phase, stored ber (Z. mauritiana) varieties were subjected to a storage study at 0, 7th, and 14th days for comparative evaluation based on titratable acidity, reducing sugar content, and ascorbic acid content. The results showed that the fruits stored at 5°C showed a maintained level of ascorbic acid content (31.26 ± 0.02 mg/100 g), reducing sugars (41.25 ± 0.02%), and titratable acidity (3.36 ± 0.01%) in Karela. On the contrary, Karela stored at 15°C showed a reduction in ascorbic acid content (28.12 ± 0.02 mg/100 g) and titratable acidity (1.21 ± 0.01%) and an increase in reduced sugar content (46.48 ± 0.03%). Moreover, Dil-Bahar variety showed higher ascorbic acid content (51.69 ± 0.05 mg/100 g), titratable acidity (3.51 ± 0.02%), and reducing sugar content (33.29 ± 0.01%) at 5°C. It was concluded that cultivars showed the best results at low storage temperatures of 5°C.