MSc

Achieving food and nutritional security necessitates the consumption of vegetables, among which green leafy vegetables (GLVs) are especially significant for their high concentration of vitamins, minerals, ascorbic acid, riboflavin, and folic acid. Due to the substantial vitamin content, GLVs can be beneficial in solving the world's nutritional problems, especially in underdeveloped nations where huge population suffers from micronutrient deficiencies, commonly referred to as "hidden hunger." Micronutrient-rich GLVs are essential for preventing malnourishment and a range of degenerative illnesses. They have been discovered to provide a range of health-promoting qualities, including as antioxidant, antibacterial, anti-inflammatory, and anticancer activities, in addition to their nutritional advantages.
The study comprised two experiments. The first experiment assessed the proximate composition of biochemicals, minerals, antioxidants, and antinutrients in leaves after shade drying and fine grinding. Basella alba exhibited the highest content of total protein (15.25%), total chlorophyll (136.91 mg/100 g), and total phenols (152.06 mg GAE/100 g), along with the lowest content of antinutrients, viz., nitrates (0.89 mg/g) and oxalates (13.46 mg/g). In contrast, Cnidoscolus aconitifolius demonstrated the highest moisture content (76.20%), crude fibre (31.05%), ascorbic acid (163.51 mg/100 g), nitrates (0.92 mg/g), and phytates (1.55 mg/g). Alternanthera sessilis was notable for its superior content of crude fat (3.81%), total carbohydrates (74.56 g/100 g), total carotenoids (24.14 mg/100 g), antioxidant activity (IC50 = 0.1544 μg/mL), and oxalates (20.43 mg/g).
The second experiment explored the dehydration and storage stability of powder of minor leafy vegetables. The blanched and unblanched leaf samples were dried in a cabinet drier until they attained constant weight and were powdered. The powders were then packed in two different packaging materials [laminated pouch and aluminium pouch] and kept in two different storage conditions [ambient and refrigerated]. The samples were analyzed for their biochemical composition (moisture, crude fibre, crude fat, total protein, total chlorophyll, total carbohydrate, ascorbic acid, total carotenoids, total phenols, and antioxidant activity), antinutrients (phytates, oxalates, and nitrates), and microbiological safety in monthly interval up to three months. Observations for sensory evaluation of leaf powders were taken after the third month.
In the second experiment, the research on biochemical parameters revealed that the highest moisture (12.36 to 9.35%), total protein (13.87 to 8.73%), total chlorophyll (117.22 to 61.62 mg/100 g), and total phenols (135.21 to 75.52 mg GAE/100 g) were observed in B. alba after the three-month duration. Meanwhile, C. aconitifolius was rich in crude fibre (26.82 to 10.90%) and ascorbic acid (145.28 to 84.79 mg/100 g). Total carbohydrates (72.78 to 57.95 mg/100 g), crude fat (2.86 to 2.44%), and total carotenoids (19.92 to 12.87 mg/100g) were found to be highest in A. sessilis during the storage period of 3 months. The treatment T6 [Unblanched + aluminium pouch + refrigerated storage] had the highest retention, and the lowest was in T3 [Blanched + laminated pouch + ambient storage].
The study on mineral content of leaf powders up on three-months storage revealed that phosphorus (1291.00 to 881.33), potassium (8110.40 to 6262.33), magnesium (1395.00 to 925.00), manganese (9.10 to 6.50), and copper (5.93 to 1.68) mg/100 g were found highest in B. alba. The retention of nitrogen (4053.80 to 3392.00 mg/100 g), sulphur (1150.00 to 385.96 mg/100 g), zinc (7.80 to 3.07 mg/100 g), and sodium (163.80 to 48.17 mg/100 g) were maximum in C. aconitifolius, whereas, the retention of calcium (3700.82 to 2845.03) and iron (40.17 to 26.70) mg/100 g were highest in A. sessilis. The treatment T6 [Unblanched + aluminium pouch + refrigerated storage] was found to have the highest retention of minerals, and the lowest was in T3 [Blanched + laminated pouch + ambient storage].
The results on antioxidant activity after three months of storage revealed that C. aconitifolius had the highest antioxidant activity. The highest antioxidant activity was seen in T6 [Unblanched + aluminium pouch + refrigerated storage] at IC50 = 7.39 μg/mL, and the lowest was in T3 [Blanched + laminated pouch + ambient storage] at IC50 = 14.74 μg/mL.
From the observations of antinutrients, it was found that a significant reduction in nitrate content was found in A. sessilis (0.83 to 0.22 mg/g), while the oxalates significantly reduced in C. aconitifolius (25.80 to 7.67 mg/g) and phytates in B. alba (1.67 to 1.12 mg/g). The treatment T3 [Blanched + laminated pouch + ambient storage] was found to have the highest reduction, and the lowest was in T6 [Unblanched + aluminium pouch + refrigerated storage].
The microbiological analysis revealed that the treatments exhibited microbial load in safe limits under ambient and refrigerated conditions for up to 3 months of storage. However, the lowest total plate count (TPC) was observed in A. sessilis (0.80 to 1.20×105 cfu/g), and the maximum was found in C. aconitifolius (0.95 to 1.35×105 cfu/g). The treatment with the lowest
TPC resulted in T8 [Blanched + aluminium pouch + refrigerated storage], and the highest was in T1 [Unblanched + laminated pouch + ambient storage].
The sensory evaluation of leaf powders (3 MAS) reported that the mean scores for appearance (T8 = 8.83) and for aroma (T5 = 8.66) were significantly higher in C. aconitifolius, whereas for colour (T4 = T8 = 8.50) and overall acceptability (T8 = 8.50) in B. alba.
These findings provide a comprehensive understanding of the nutritional and biochemical profiles of these underutilized, minor leafy vegetables, highlighting their potential for value addition and emphasizing effective post-harvest management in preserving their nutrient content. Value addition through dehydration and cold storage, combined with modern packaging techniques, ensures these vegetables retain their nutrition without compromising quality. Studies should focus on developing advanced preservation and packaging solutions tailored to minor leafy greens, enhancing their contribution to global food and nutrition needs in a sustainable and scalable way