Antioxidant activity of membrane-fractionated coffee extracts in dependence of the storage conditions

Present paper aims at one of the important aspects of the application of products with antioxidant activity: namely the preservation and change of their properties during the storage in different conditions, as well as their reliable characterisation. The tests of antioxidant properties were conducted with membrane-separated coffee extracts, isolated using a "Microdyn Nadir NP030P" type of commercial nanofiltration membrane (30% retention of NaCl; MWCO~400). Prepared coffee permeates and retentates were stored 0÷10 days in cool/warm conditions, with/without air access and at different illumination conditions. The kinetics of content changes was evaluated according to Folin-Ciocalteu method of total phenolic/reducing content determination.