Antioxidative and sensory properties of instant coffee fortifiedwith galactose-fish skin gelatin hydrolysate maillard reaction products

Antioxidative Maillard reaction product (MRP) prepared from the mixture of galactose-gelatin hydrolysate from unicorn leatherjacket skin was fortified in instant coffee brew at different levels (0, 0.5, 1.0 mg/mL) and the resulting brew was characterised. Addition of MRP up to 1.0 mg/mL had no effect on browning index, L*, a*, b*, ΔE* and ΔC* of coffee brew (P>0.05). The pH value of resulting instant coffee brew was decreased with increasing MRP level added (P<0.05). ABTS radical scavenging activity and ferric reducing antioxidant power of coffee brew increased as MRP levels increased (P<0.05). Based on sensory evaluation, there were no differences in likeness score between coffee brew fortified with MRP at all levels used and the control (without MRP). Much higher abundances of cyclohexanone and dimethydisulfide were observed in coffee brew added with MRP, compared with the control. Thus, MRP could serve as the rich source of antioxidant, which could be supplemented in coffee brew without negative effect.