Effect of pre-treatments and drying on the quality attributes of dried rhododendron flowers

Abstract

Rhododendron is a highly perishable and nutritious flower abundant in phytocompounds. However, due to its availability for a short span, it is not much exploited by food researchers. Therefore, the aim of the current study was to optimize the pre-treatments for drying of Rhododendron with maximum phytochemical retention. The effect of different variables was evaluated on the physico-chemical parameters (such as moisture, ash, protein, total sugars and reducing sugars) and phytocompounds (such as ascorbic acid, carotenoids, anthocyanin, total phenols, flavonoids, antioxidant activity and tannins). All the quality attributes were significantly (p ≤ 0.05) affected by blanching treatment and dipping time. Among the chemical pre-treatments, KMS had a significant (p ≤ 0.05) effect on the retention of all phytochemicals, whereas, citric acid could not possess a significant (p ≤ 0.05) effect on the phytochemicals. The optimum process conditions for Rhododendron flowers were found to be 3 min blanching time, 2000 ppm KMS, 0% citric acid, and 26.28 min dipping time along with 0.917 desirability. In the nutshell, it is concluded that KMS in combination with blanching, prior to drying has been proven beneficial in the preservation of the phytocompounds and has the potential to utilize as a new ingredient in various food products.

Keywords

• Citric acid
• Phytocompounds
• Potassium metabisulfite
• Pre-treatments