Impact of chitosan coatings on shelf-life, nutrient elements and biochemical qualities of country beans (Phaseolus lunatus L.) at postharvest storage

Purpose: In Bangladesh, postharvest damage to various vegetables is common because of a lack of appropriate technologies. Country beans (Phaseolus lunatus L.), one of Bangladesh’s main winter vegetables, are cultivated throughout the country, which provides numerous health advantages. A research experiment was performed to measure the impact of chitosan covering on weight loss, shelf-life, and some nutritional characteristics of country beans at postharvest storage. Research Method: The experiment was set up in a completely randomized design (CRD) with three replications and four treatments at room temperature (≈23-25ºC), and the treatments were: T0 (control), T1 (coating with 0.10% solution), T2 (coating with 0.20% solution) and T3 (coating with 0.30% solution). Findings: The use of 0.20% chitosan prevented weight reduction by 1.59% as compared to the control and extended the shelf-life up to 23.3% in country beans at 10 and 12 days after postharvest storage (DAPS), respectively. Chlorophyll-a, chlorophyll-b and total chlorophyll contents varied from 0.75-1.59, 1.36-2.86 and 2.11-4.45 mg g-1 tissue at 5 DAPS and 0.61-1.26, 1.10-2.27 and 1.70-3.53 mg g-1 tissue at 10 DAPS, respectively. Chitosan treatment T2 significantly enhanced calcium (0.77%) and phosphorus (0.51%) contents in the country beans during postharvest storage at 5 DAPS. Additionally, treatment T3 significantly increased total phenolics (3.06 mg 100g-1 tissue) in the country beans during postharvest storage at the same DAPS. Research limitations: The study could not measure some traits (i.e., anti-radical activity, the activity of antioxidant enzymes, etc.) due to a lack of laboratory facilities. Originality/Value: This experiment revealed that country beans covered with 0.20% chitosan solutions could be utilized to enhance several nutritional properties, check weight loss, and prolong the shelf-life.