The hypothesis that free ferulic acid in stored orange juice contributes to the objectional aroma of p-vinyl guaiacol (PVG) was tested. Singlestrength orange juice (SSOJ) contained 185 pLgn free ferulic acid which increased to 316 p&L after pasteurization. Commercial samples of SSOJ contained 3.7m& free ferulic when incubated at 35°C for 28 days; incubation at 5O"C, resulted in 9.5 mg/L, while samples kept at 4°C contained 2.9 mg/L. Simultaneously, PVG content in SSOJ increased by 2-(35°C) to 3-(50°C) fold, while addition of ferulic acid accelerated formation of PVG. Inclusion of orange juice with added ferulic acid, produced a less acceptable aroma (laboratory taste panel) than juice incubated without added ferulic acid.