Martina Cassarino, Gianluca Giuberti, Margherita Dall’Asta, Hanieh Moshtaghian, Marta Bianchi
. NRF11.3 and NR-FIcarb emerged as the most suitable functional units for carbon footprint calculations, showing moderate, statistically significant positive correlations with wholegrain content (ρ = 0.452 for NRF11.3, ρ = 0.475 for NR-FIcarb, both p < 0.001) and effectively rating grain-food categories in line with dietary guidelines. Transitioning from a weight-based to a nutrition-based functional unit, expressed as either NRF11.3 or NR-FIcarb, did not alter the finding that rice and sweet bakery products had the highest greenhouse gas emissions. However, it highlighted the favorable nutritional quality of "hard bread and crusts" and "flour, cereals, grains, and crushed cereals," leading to reduced carbon footprints. These findings demonstrate that NRF11.3 and NR-FIcarb are equally effective in assessing the quality of grain-based foods and can be applied in food life cycle assessments, providing a practical tool for identifying foods with lower climate impact and higher nutritional value.