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This study aims to evaluate functional properties of rice starch‐based nanocomposite (NC) films. Silver nanoparticles (SNP) are synthesized using Saraca asoca leaf extract and found to be spherical with diameters ranging between 27 and 45 nm. The SNP solution is added at three different levels: 50, 100, and 150 mL to filmogenic solution (150 mL) and these films are designated as SNP‐50, SNP‐100, and SNP‐150, respectively. In addition to a control film, two more films are made by adding AgNO3 solution (150 mL) and plant extract (150 mL) into filmogenic solutions. Addition of SNP improves tensile strength and decreases elongation at break of rice starch films. NC films show enhanced UV–vis light barrier properties due to increased color intensity and opacity. SNP added films exhibit lower water solubility, water holding capacity, and water vapor permeability. Scanning electron microscopy suggests that control film, SNP‐50, and SNP‐100 have the smoothest surfaces in comparison to all films. SNP incorporation delays biodegradation of films. Silver nanoparticles in the form of colloid, filmogenic solution, and even as discrete films show excellent antibacterial activity against common food pathogens. The SNP concentration significantly correlates (R2 = 0.62–0.96) to the functional properties of films.

T omato (Lycopersicon esculentum Mill.) from the family of Solanaceae is one of the worldwide important vegetables has essential because it can consume as fresh and also in processed forms (Mutari and Debbie, 2011). Tomatoes are perishable in nature, in Pakistan during high temperature the production decreases and causes the loss of supply of tomato in summer season as compared to winter (Tahir et al., 2021). Values of tomatoes are increasing on daily basis as tomatoes are rich in many nutritional components Abstract | This study evaluates changes in physiological i.e., ash content, moisture content, pH, (total titratable acidity) TTA, (Total soluble solids) TSS, antioxidant activity using 2, 2-diphenyl, 1-picryl hydrazyl (DPPH) and antimicrobial activity in Roma VF tomato variety was assessed within three different mature levels viz., green, pink and red. Outcomes from recent study pointed out that maturity levels involved to change the quality of tomato. Moisture and ash increased with the maturity ranged from 89.38±0.54 to 93.34±0.48 and 0.35±0.02 to 0.41±0.02% respectively. pH increases 4.23±0.15 to 4.77±0.15 and % Titratable acidity decreased 0.77±0.03 to 0.62±0.01 with the increase in ripening. In addition, increase in TSS (5.1-6.0 o brix) and juice content with maturity stages (20.3-28.6 ml 500gm-1) from green to red tomatoes. Antioxidant activity (DPPH) continuously increased from green to red tomato level (37.5-46.3 %). Lycopene content is an antioxidant also increased from 22.1-33.5 mg/kg. Vitamin C content increase from green to pink (4 mg/100 g f.w to 17mg/100g f.w), then decrease till reached towards final stages red 14.5mg/100g f.w indicating decaying of fruits. Antimicrobial activity revealed that mature green has higher activity comparison to half and full ripe stages. Green stages showed ZOI of antimicrobial (10.7-11.6mm) and for antifungal (11.2-11.8mm) in methanol and acetone extracts. It was concluded from the results that ripening stage has effects on the nutritional values which point out that the ideal maturity stage to maintain optimal postharvest storage ability and nutritional value is breaking stage of fresh tomato which is the most suitable for storage.

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