Calcium and vitamin D3 fortification of almond milk: A chemical engineering approach to enhancing nutritional quality and mineral bioavailability

Background: The increasing demand for plant-based dairy alternatives has highlighted almond milk as a popular option due to its favorable sensory properties and suitability for individuals with lactose intolerance or milk protein sensitivity. However, its inherently low levels of calcium and vitamin D3 limit its nutritional equivalence to cow’s milk, particularly in populations with higher mineral requirements. Aim: This study aimed to enhance the nutritional and functional quality of almond milk through calcium and vitamin D3 fortification, while evaluating its physicochemical characteristics, mineral bioavailability, and sensory acceptability. Methods: Almond milk was prepared using an almond-to-water ratio of 1:4, followed by fortification with calcium chloride (0.3 g/100 mL) and vitamin D3 (80 IU/100 mL). Physicochemical properties were analyzed using standard methods, while calcium bioavailability was assessed using an in vitro digestion model based on the INFOGEST protocol. Mineral quantification was performed using atomic absorption spectrophotometry. Sensory evaluation was conducted to assess product acceptability. Results: Fortification significantly increased calcium content from 13.99 to 120 mg/100 mL without altering macronutrient composition. Physicochemical parameters such as density, electrical conductivity, and total salts increased, indicating effective dissolution and homogeneous distribution of the added minerals. In vitro digestion revealed progressive calcium release, with bioavailability reaching 65.41% during the intestinal phase. Sensory evaluation demonstrated high acceptability, with no adverse effects on flavor, texture, or appearance. Conclusion: Calcium and vitamin D3 fortification effectively improves the nutritional profile and functional performance of almond milk. The integration of food science and chemical engineering principles enables the development of a stable, bioavailable, and consumer-acceptable plant-based beverage, supporting its potential as a viable alternative to dairy milk.