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Carambola is an excellent source of vitamin C (vit‐C) and possesses many nutritious properties. This research was directed to moisture sorption isotherm, air drying kinetics, and vit‐C degradation throughout blanching, storage, and drying of carambola. Fresh carambola contained 91.44% moisture and 24.2 mg/100 g vit‐C. The monolayer moisture content was 7.3 g/100 g solid according to Brunauer, Emmett, and Teller (BET) equation. The drying process (cabinet dryer) at different temperatures and sample thickness exposed that more the temperature, higher the drying rate at a constant thickness. Furthermore, drying rate was declined at a constant temperature with the rise of sample thickness. The samples pretreated with citric acid showed the lowest drying time and vit‐C degradation in blanching. The influence of drying temperature and duration on the retention of vit‐C was also analyzed. The activation energy (Ea) of the vit‐C loss was 9.24 kcal/g‐mole. Higher the exposure at a constant temperature, more the reduction of vit‐C content as per first‐order reaction kinetics. During room temperature storage of whole carambola in 3 and 12 days showed 13.7% and 41.2% loss of vit‐C, respectively. Vit‐C degradation was lower for blanched than non‐blanched samples in refrigeration storage, while this change was relatively lower for both in frozen storage. Scanning electronic microscopic (SEM) studies were conducted to evaluate the effects of temperature and pretreatment on the surface morphology of dried carambola. Practical applications: Carambola grows abundantly in Bangladesh. Nevertheless its availability and nutritive significance, it is not so utilized and popular in the fruit market. This yields postharvest difficulties for chemical and microbial spoilage due to its perishability. Therefore, drying of this fruit is an utmost operative and cost‐effective process. Thus, it will be accessible in off‐season and can be used for the development of new products with these dried fruits. The present investigation explores the physical and chemical properties of carambola to reveal its prospective in fruit processing. Presented information and results of this research can assist the food technologist in implementing the drying method and storage condition of carambola. [ABSTRACT FROM AUTHOR]

We investigated the aqueous and ethanolic extracts of different forms (local names: mura and chora) of turmeric (Curcuma longa) from the Khulna and Chittagong divisions of Bangladesh for their antioxidant properties and polyphenol, flavonoid, tannin, and ascorbic acid contents. The antioxidant activity was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicalscavenging activity and ferric reducing antioxidant power (FRAP) values. The ethanolic extract of Chittagong's mura contained the highest concentrations of polyphenols (16.07%), flavonoids (9.66%), and ascorbic acid (0.09mg/100 g) and chora resulted in high yields (17.39%). The ethanolic extract of Khulna's mura showed a higher DPPH radical-scavenging activity with the lowest 50% inhibitory concentration (IC50) (1.08 κg/mL), while Khulna's chora had the highest FRAP value (4204.46 ± 74.48 M Fe [II] per 100 g). Overall, the ethanolic extract had higher antioxidant properties than those in the aqueous extract. However, the tannin concentration was lower in the ethanolic extract. We conclude that the turmeric varieties investigated in this study are useful sources of natural antioxidants, which confer significant protection against free radical damage. [ABSTRACT FROM AUTHOR]