Purple-fleshed dragon fruit is gaining popularity worldwide due to its distinctive characteristics and health benefits. This climbing cactus, introduced to humid tropical climates, presents challenges in assessing fruit quality. The dynamic transformations in fruit color, bioactive compounds, and textural attributes across 11 developmental stages from 10 to 32 days after flowering under humid tropical conditions were studied. Color analysis revealed significant intensification of red-violet hues, with L* values decreasing by 14.74% and a* values increasing from −8.14 to 32.96. The color transformation is initiated in the pulp at 25 days and the peel at 27 days after flowering. Betalain synthesis commenced after 20 days with rapid accumulation between 25 and 32 days, correlating with color development. Antioxidant activity increased from 79.38% at 10 days to 86.76% at 20 days, followed by a steady decline. Phenolic content peaked at 121.40 mg gallic acid equivalent per 100 g at 25 days before declining, while the flavonoid content decreased with the advancement of fruit development. Concurrent reduction in peel thickness and fruit firmness was also observed. These findings show that purple-fleshed dragon fruit can adapt well to humid tropical conditions, with a 32-day developmental cycle, offering vital insights into quality and maturation phases.

The continuous demand for safe, high-quality, and nutritionally superior food has catalysed the evolution of innovative food processing technologies. Flash Vacuum Expansion (FVE) stands out as a transformative method, bridging the gap between traditional thermal and non-thermal techniques by leveraging the principles of rapid pressure manipulation and thermal efficiency. Through the application of high-saturated steam pressure followed by abrupt decompression, FVE restructures biological matrices, delivering notable enhancements in drying speed, microbial decontamination, and the recovery of valuable bioactive compounds. This review delves into the multifaceted applications of FVE in food processing, spanning laboratory experiments to full-scale industrial practices. The technology has proven instrumental in accelerating drying processes for fruits and vegetables, resulting in significant reductions in processing time and energy costs. Furthermore, FVE optimizes the extraction of essential oils, antioxidants, and other nutraceutical components, enriching the functional and nutritional profiles of food products. Its efficacy in microbial decontamination, including the eradication of spores and vegetative cells, alongside the mitigation of allergenic and anti-nutritional factors, underscores its versatility. Over recent decades, FVE has reshaped food processing paradigms, enhancing both product quality and operational efficiency. This article examines the current advancements, successful industrial implementations, and untapped potential of FVE, positioning it as a pivotal technology for future food processing innovations.