Accelerated ageing of cocoa mucilage wine through hydrodynamic cavitation

Abstract

Affordable source of vital vitamins, minerals, and antioxidants. Among them, Moringa oleifera Lam., often called the "miracle tree," stands out for its exceptional nutritional and medicinal properties. Its leaves are rich in bioactive compounds with antioxidant, anti-inflammatory, and antimicrobial benefits, contributing to improved nutrition and addressing malnutrition, especially in rural households. However, the high moisture content of fresh Moringa leaves makes them highly perishable, necessitating effective post-harvest management to extend their shelf life. Proper dehydration techniques not only reduce spoilage but also help retain their nutritional value, ensuring year-round availability. Converting Moringa leaves into powder enhances their stability and facilitates their incorporation into value-added products. Additionally, suitable packaging and storage conditions play a crucial role in preserving quality and minimizing post-harvest losses. Despite its significance, research on optimizing postharvest handling of Moringa leaves remains limited in Kerala. Hence with this background the present study entitled “Standardisation of dehydration, storage and packaging of drumstick (Moringa oleifera Lam.) leaves” was undertaken to standardize pretreatment methods, dehydration techniques, and suitable packaging materials and storage conditions to enhance the shelf life and preserve the nutritional integrity of Moringa oleifera Lam. leaves. The study was structured into three experiments. The first experiment was to standardise the pretreatments of Moringa leaves. Fresh Moringa leaves were collected, destalked, washed, and subjected to four treatments: control (no blanching), hot water blanching (80°C for 1 min), steam blanching (1 min in a steam cooker), and microwave blanching (800 W for 30 s). Blanched leaves were rapidly cooled, shadedried, powdered, and analysed for physical and biochemical properties including recovery percentage, moisture content, crude fibre, crude fat, total protein, total ash, total carbohydrate, ascorbic acid, total chlorophyll content, total carotenoids and total phenols. The results revealed that blanching treatments significantly influenced the physical and biochemical parameters of Moringa leaves. Microwave blanching (T4) emerged as the most effective pre-treatment, yielding the highest recovery percentage (22.81%), lowest moisture content (8.48%), and maximum retention of crude fibre (13.50%), total carbohydrates (42.00%) and carotenoids (114.48 mg/100g). Steam blanching (T3) and hot water blanching (T2) also showed significant improvements in nutrient retention compared to the control (T1). The control treatment exhibited the lowest recovery (17.94%) and highest moisture content (11.64%), highlighting the importance of blanching in reducing moisture and enhancing nutrient concentration. Microwave blanching also retained higher levels of total ash (12.38%), total protein (24.23%), ascorbic acid (115.61mg/100g), and total chlorophyll (299.80%) and crude fat (7.53%), making it the best pre-treatment method. Moringa leaves blanched by microwave blanching were subjected to different dehydration methods, including shade drying (23–31°C), cabinet drying (50±5°C), microwave oven drying (60°C), and vacuum drying (35±5°C). After drying, the leaves were powdered and analysed for physical (recovery percentage), biochemical (moisture content, crude fibre, crude fat, total protein, total ash, total carbohydrate, ascorbic acid, total chlorophyll content, total carotenoids and total phenols.), mineral (Fe, Ca and K), and antioxidant properties. The results demonstrated that dehydration methods significantly influenced the physical, biochemical, mineral, and antioxidant properties of Moringa oleifera leaves. Vacuum drying (T4) resulted in the highest recovery percentage (28.23%), total carbohydrate (48.00%), total protein (26.28%), total ash (22.42%), ascorbic acid (139.02 mg/100 g), and total phenols (160.91 mg GAE/100 g), while also exhibiting the highest antioxidant activity (IC₅₀: 3.82 mg/ml). Microwave drying (T3) recorded the highest total carotenoid content (119.43 mg/100 g) and retained notable amounts of crude fat (7.42%) and iron (13.34 mg/100 g). Cabinet drying (T2) yielded the highest crude fibre (9.70%) but the lowest crude fat (5.77%) and protein content (23.33%). Shade drying (T1) retained the highest total chlorophyll (324.41 mg/100 g) and crude fat (8.69%) but had the lowest recovery (24.28%) and total carbohydrate content (42.33%). Vacuum drying emerged as the most effective dehydration method, followed by microwave drying, due to their superior retention of key nutrients and antioxidant properties.