Antioxidant and angiotensin I-converting enzyme (ACE)-inhibitory potential of spicy Cheddar cheese prepared from cow's milk after in vitro digestion

This study evaluated the antioxidant and angiotensin-I converting enzyme (ACE) inhibitory activities of processed Cheddar cheese fortified with cloves, cumin, or black pepper during 0–9 months of storage. Freeze-dried ethanol-soluble extracts (ESE) and water-soluble extracts (WSE) collected during ripening were also examined. The WSE of black-pepper cheese showed the strongest antioxidant activity, with higher DPPH radical scavenging ability (1516.4 ± 180 µmol Trolox equivalent/g) and reducing power (38.12 ± 0.38 µg/g), along with the highest total phenolics (82.48 ± 3.2 µg GAE/g). After simulated gastrointestinal digestion, the antioxidant properties significantly increased in all the treatments. Digested black-pepper cheese exhibited the highest total antioxidant activity (5752.8 ± 83.3 µg Trolox equivalent/g), while control cheese showed the lowest (4603.3 ± 86.2 µg Trolox equivalent/g). Overall, digested spiced cheeses showed superior antioxidant and ACE-inhibitory activities compared to their corresponding freeze-dried extracts. Results highlight digestion-released bioactive compounds and support spiced Cheddar cheeses as promising functional dairy products.