Production of Sustainable Food Ingredients From Watermelon Wastes Using Drum-Drying

Abstract

Watermelon is among the most widely cultivated fruits globally, yet it suffers a high waste rate of 45% due to its short shelf life. In 2023, global watermelon production reached 99.7 million tons, with China and Türkiye contributing 60.1 million and 3.5 million tons, respectively. This study explores the potential of processing discarded watermelons into long-lasting food ingredients to mitigate waste and enhance sustainability. Two test samples were developed: one combining watermelon pulp with flour, and another incorporating both watermelon pulp and rind with flour. The research also highlights the underutilized potential of watermelon rind as a valuable food ingredient. Experiments using a drum dryer produced ingredients with a moisture content of 3.40–3.77 g/100 g and water activity of 0.361–0.37, ensuring an extended shelf life. The new ingredients, rich in sugars and dietary fiber, offer a sustainable, natural alternative for industrial applications and can be produced 15.8%–19.1% cheaper than the value of their components. Redirecting 45% of global watermelon waste into food ingredients could potentially offset 2.7 million tons of CO2e emissions globally and 94,500 tons of CO2e in Türkiye annually. This study not only provides a sustainable solution to watermelon waste but also emphasizes efficient agricultural land use, reduced carbon emissions, minimized water consumption, and higher-quality product development. By transforming a frequently discarded by-product into valuable food ingredients, this research supports global sustainability efforts and promotes innovative approaches to reducing food waste.