Sustainability Evaluation of Plant-Based Beverages and Semi-Skimmed Milk Incorporating Nutrients, Market Prices, and Environmental Costs

Abstract

Developing a reliable method to compare food sustainability is gaining traction, with efforts like those by the Food and Agriculture Organization (FAO). This research aims to contribute to a comprehensive scientific comparison of food categories based on CO2 emissions linked not to weight but to their primary function: nutrient availability and uptake in the consumer’s body. The study utilizes a multi-criteria evaluation for sustainability, incorporating the Nutrient Rich Food (NRF) score, protein digestibility, and essential amino acid content. A case study compares one serving of semi-skimmed milk (SSM) with various plant-based beverages (oat, soy, rice, coconut, and almond), considering their carbon footprints in relation to nutrient content and environmental costs. The analysis integrates protein quality through essential amino acid proportion and digestibility. Findings reveal that achieving an NRF11.3 score of 50 requires more servings of unfortified plant-based beverages than semi-skimmed milk, resulting in higher carbon footprints, except for soy drink. However, when considering emerging farm management measures, semi-skimmed and soy drinks show comparable carbon footprints for a given NRF score. Fortified plant-based beverages (soy, oat, and almond) exhibit lower footprints relative to the calculated NRF scores. Yet, when converting carbon footprints to euros using the European Union Emissions Trading System and adding them to retail prices per kilogram, semi-skimmed milk emerges as the option with the lowest “societal costs” (environment and consumer costs). The research underscores that understanding a food product’s nutritional value requires more than knowledge of its composition; uptake into the body maintenance and potential synergistic effects of other components in the food matrix play crucial roles.