Fat concentration and high-pressure homogenization affect chlorogenic acid bioaccessibility and α-glucosidase inhibitory capacity of milk-based coffee beverages

Abstract

This study aimed at investigating the effect of coffee formulation and high-pressure homogenization (HPH) on chlorogenic acid bioaccessibility and α-glucosidase inhibition.Coffee was added with milk (1:1) containing 0.1, 3.6 or 7.1% fat, homogenized at increasing pressure (0–150 MPa) and in vitro digested. Using milk with the highest fat concentration (7.1%) promoted the formation of smaller particles after HPH treatment, as well as upon digestion. Digested samples with the highest fat content also presented lower ζ-potential, suggesting higher stability. Chlorogenic acids (CGAs) bioaccessibility and α-glucosidase inhibition were evaluated upon in vitro digestion. CGAs bioaccessibility increased from nearly 25% to >50% by adding milk and using HPH. These could promote CGAs micellarization, reducing their susceptibility to degradation during digestion. Properly combined milk and HPH also improved α-glucosidase inhibitory effect. No correlation was found between CGAs bioaccessibility and α-glucosidase inhibition, suggesting that other components may govern antidiabetic properties of coffee.

Keywords

• Coffee
• Milk
• Fat concentration
• High pressure homogenization
• In vitro digestion
• α-glucosidase inhibition