Environmental Assessment of Whey Valorization in Dairy Products in Kenya

Purpose In Kenya, a growing dairy sector anticipates increased demand for processed products like cheese. Whey, a significant by-product of dairy processing, can substitute milk in dairy products reducing environmental pressures from milk production. Additionally, whey management practices, including occasional discharge into aquatic environments, contribute to harmful eutrophication. No quantification of environmental effects of whey valorization in dairy products, however, exists in the scientific literature. Methods Utilizing dairy product formulations and current whey management estimates, we conducted a Life Cycle Assessment (LCA) to evaluate net environmental effects of replacing milk-based products with whey-based alternatives. The assessment focused on climate change, eutrophication, and land use impacts. Results Findings indicate potential environmental benefits across all impact categories. Substituting milk with whey could avoid approximately 1.2 kg CO₂-equivalent emissions, 1 g of phosphorus-equivalent eutrophication, and 6 m²·year of land use per kilogram of product. Extrapolating results to national whey quantities, utilizing 10% of projected end-of-decade whey to replace milk-based products could yield environmental savings of approximately 6,000 tonnes CO₂-equivalent, 5,000 kg phosphorus-equivalent, and 3,000 hectare·years of land use. Conclusion The environmental rationale for promoting the development and production of whey-based dairy products in Kenya has been quantified. While the conclusion is robust, results are sensitive to the proportion of whey discharged into the environment, the phosphorus removal efficiency in wastewater treatment, and the substitutability between products. These factors warrant careful consideration and improved data collection in Kenya's expanding dairy industry and in whey valorization contexts where this study’s approach is reusable.