Impact of bovine lactoferrin fortification and storage period on the flavor profile and volatile compounds of yogurt

This study aimed to determine the effect of lactoferrin (LF) fortification of bovine milk on yogurt flavor and volatile compound profiles during the 21-day storage period. Experimental yogurt samples containing 750.6 mg/L of LF were produced. LF fortification increased viscosity on the first day of storage and reduced syneresis, while a * and b * showed only minor fluctuations without perceptible color differences. Flavor profile analysis revealed that the “sweet” taste was perceived at a higher intensity in LF-fortified yogurt compared to the control on the first day of storage (control: 2.89; LF-fortified: 3.75). Furthermore, the incorporation of LF influenced the textural properties of the yogurt, resulting in increased astringency during storage. The increased astringency can be explained by LF's interactions with milk proteins, which strengthen the gel network. The volatile compound profiles were generally similar between the control and LF-fortified yogurt samples. In LF-fortified yogurt samples, 2-butanone decreased by the end of storage (from 11.51 to 9.06 μg/kg), whereas benzaldehyde was detected only on day 1 (9.37 μg/kg). LF fortification of A2 yogurt is feasible and subtly improves properties while preserving quality, suggesting for value-added dairy products; further studies should assess formulations and bioactivity.