In Vitro Study for The Bio accessibility of Micronutrients in Fortified Plant-Based Products and Meat Analogues
Keywords:
Plant-based alternatives, bioavailability, bioaccessibility, in vitro digestion, iron, zinc, vitamin B12, phytic acid, food matrix, fortificationAbstract
The global shift towards plant-based diets has heightened the need to critically evaluate the nutritional adequacy of meat and dairy alternatives beyond their macronutrient profile. While many products are fortified to match the micronutrient content of animal products, their bioavailability remains a significant concern. This study conducted a comparative analysis of the content and in vitro bioaccessibility of critical micronutrients iron, zinc, and vitamin B12 in commercial plant-based burgers (PBBs) and milks (PBMs) against their animal-based counterparts (beef burgers, BBs; bovine milk, BM). Using ICP-MS and HPLC for quantification and the INFOGEST 2.0 protocol to simulate digestion, we found that fortified PBBs contained significantly higher total iron than BBs but exhibited drastically lower iron bioaccessibility (25-32% vs. 58-63%, p < 0.05). This disparity is strongly correlated with phytic acid content and attributed to the inherent susceptibility of non-heme fortificants to inhibition within the complex plant matrix. Zinc bioaccessibility was similar between PBBs and BBs (~30-40%), though lower total zinc in PBBs resulted in a lower absolute bioaccessible amount. Conversely, in the liquid matrix of fortified PBMs, iron and zinc bioaccessibility was significantly higher than in PBBs and was statistically equivalent to BM. Vitamin B12 bioaccessibility was consistently high (>78%) across all fortified products and BM. These results reveal a critical "bioavailability gap" in solid plant-based analogues: high fortification levels do not guarantee sufficient absorption due to food matrix effects and anti-nutritional factors. The findings underscore an urgent need for the industry to adopt advanced strategies, such as selective fortificants, anti-nutrient reduction, and encapsulation technologies, to enhance micronutrient delivery and ensure the long-term nutritional efficacy of plant-based products.
