High-Value Compounds in Papaya By-Products (Carica papaya L. var. Formosa and Aliança): Potential Sustainable Use and Exploitation

Abstract

Background: Food waste is a global and growing problem that is gaining traction due to its environmental, ethical, social, and economic repercussions. Between 2022 and 2027, the worldwide papaya market is expected to have a huge increase, meaning a growth in organic waste, including peels and seeds. Thus, this study evaluated the potential use of peels and seeds of two mature papaya fruits as a source of bioactive compounds, converting these by-products into value-added products. Proximate analysis (AOAC methods), mineral content (ICP-MS), free sugars (HPLC-ELSD), fatty acid composition (GC-FID), vitamin E profile (HPLC-DAD-FLD), and antioxidant activity (DPPH and FRAP assays) were evaluated. Results: Both by-products showed high total protein (20–27%), and dietary fiber (32–38%) contents. Papaya peels presented a high ash content (14–16%), indicating a potential application as a mineral source. 14 fatty acids were detected, with α-linolenic acid (30%) as the most abundant in the peels and oleic acid (74%) in the seeds. Both by-products showed high antioxidant activity. Conclusion: Papaya by-products display great potential for industrial recovery and application, such as formulation of new functional food ingredients.

Sustainable Utilization of Food Biowaste (Papaya Peel) Extract for Gold Nanoparticle Biosynthesis and Investigation of Its Multi-Functional Potentials

“…While papaya (mainly its fruit) can be eaten fresh, it is acknowledged to be generally used in food manufacturing industries to make processed foods (mainly the fruit pulp), while other parts such as the peel and seeds are discarded [13]. Some earlier reports have reported that around 32% of non-edible pulp, 8.47% of peel, and 6.51% of seeds are produced as waste during industrial food processing which are mostly discarded as food waste materials [13][14][15][16]. The accumulation of huge amounts of papaya peels (food waste) after its pulp is utilized remains an environmental issue, as the solid wastes transmit life-threatening diseases and there are no sustainable management systems for this huge and year-round production of bioresource waste materials.…”

“…The accumulation of huge amounts of papaya peels (food waste) after its pulp is utilized remains an environmental issue, as the solid wastes transmit life-threatening diseases and there are no sustainable management systems for this huge and year-round production of bioresource waste materials. Thus, the use of papaya food waste materials such as peels in a sustainable manner can add to decreasing food insecurity and enhance food sustainability, specifically in the underdeveloped countries of the world [16]. There is a report of ripened papaya peels used as biofertilizers [17].…”