In tropical countries, the mango sector generates high volumes of byproducts (peel, seeds, rejects, etc.) that need to be valorized. This research carried out on Cambodian Keo Romeat mango waste, was undertaken to support the mango industry. The aim was to better understand how ripening stage and processing method impact the final quality of the products, e.g., animal feed, especially as regards to soluble pectin and fiber content. Mangoes were selected from four ripening stages from young (i.e., green) to over-ripe mango, and processed using blanching and drying, drying or freeze-drying. The characterization of macronutrient (pectin, fiber, ash, lipid, carbohydrate and moisture) content was achieved in pulp and peel for each ripening stage and process treatment. Results showed that both processing and ripening had a significant impact on fiber and soluble pectin content even if ripening always had a greater effect. Maximizing both pectin and fiber contents in the mango pulp or peel was not possible, since the anti-correlation between their concentrations during ripening presented an R² of >0.7. Indeed, when fiber content decreased, the pectin content increased in mango peel and pulp. A simple 4-dimensional data representation was helpful for industrial growers and processors, enabling them to make suitable and appropriate choices between ripening and the processing needs according to the desired product quality without requiring specialized knowledge in food science.