Technological advances and trends in guava drying-a comprehensive overview

Guava (Psidium guajava L.), a tropical fruit known for its immense benefits, has high perishability, leading to significant post-harvest losses. Drying is important preservation method to extend its shelf life and make it more accessible as a food product. This article comprehensively reviews various drying methods, including traditional (solar and osmotic drying) to modern techniques (spray, freeze, cast-tape, foam-mat microwave-assisted drying, and heat pump drying), their impact on nutrients and composition as well as their key advantages and disadvantages. Spray drying is an efficient method for producing guava powders but faces challenges such as stickiness and nutrient degradation. Freeze-drying preserves most of guava's nutritional and sensory qualities but is cost-intensive. Microwave-assisted drying, is gaining popularity for guava processing due to its rapid drying with minimal nutrient loss. Foam blanket drying utilizing low temperatures produces high-quality porous guava products while retaining essential nutrients and volatile compounds. Heat pump drying is low-cost technique and could be used as alternative preservation technique in food industry. Comprehensive understanding of these drying methods helps choose suitable techniques for industrial use as well as improves product shelf life and consumer appeal.