Green Coffee Extracts: Advances in Green Extraction, Bioactivity, and Food Applications with Emphasis on Sustainable Processing

Abstract

Green coffee extract (GCE) has become a topic of interest due to its rich bioactive compound content and potential health benefits. This article presents a comprehensive review covering the composition of green coffee, coffee bean processing, extraction methods, health benefits, GCE microencapsulation and applications in food products. Green coffee beans contain substantially higher levels of chlorogenic acids (CGA) than roasted beans, with reported values of 543.23 ± 8.92 mg/L in green coffee compared with 90.53 ± 12.97 to 270.93 ± 10.76 mg/L after roasting, reflecting the well-documented degradation of CGA during thermal processing. Among the extraction approaches evaluated, microwave-assisted extraction (MAE) consistently provides the highest yields, producing extracts containing 34.08–40.06% caffeine and 46.41–61.87% CGA. Evidence from clinical studies indicates that GCE supplementation (10–6000 mg/day for 4–12 weeks) in overweight and obese individuals is associated with reductions in BMI and circulating insulin levels. In addition, microencapsulation by spray drying using a combination of agave fructans and gum arabic as wall materials reported in an encapsulation efficiency of 94.36%. As a food ingredient, GCE has been applied at levels of 0.025–12%, contributing to improved oxidative stability during storage for up to 90 days, enhanced antioxidant capacity, and better acceptance in terms of aroma and texture. These various study results indicate that GCE has promising prospects due to its numerous benefits in the fields of food and health, making this review a useful reference for future studies, even though in vivo clinical trials on GCE have not yet been conducted.