title: Fate of resveratrol and piceid through different hop processings and storage times.
abstract: Trans-Piceid and trans-resveratrol contents of hop cones, hop pellets, CO2 extracts, and spent hop from American varieties (harvest 2004) were determined by reverse-phase high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry [RP-HPLC-APCI(+)-MS/MS]. Pelletization induced strong stilbene degradation in some cultivars. Similarly, 1 year of storage at 4 degrees C led to a huge loss of trans-piceid, especially in the case of hop cones (much faster than in model media, although well protected from light and oxygen). Therefore, after 8 months of storage, the overall stilbene content was in the same range whatever the conditioned form. Absent in fresh hop cones or pellets, cis-resveratrol was released from cis-piceid in all stored samples. On the other hand, no delta-viniferin was detected despite it is present in light-protected model media spiked with trans-piceid. Because supercritical carbon dioxide proved inefficient for recovering resveratrol and piceid from pellets, spent hop emerged as the most interesting material for subsequent specific stilbene extraction.
authors.affiliation: Unité de Brasserie et des Industries Alimentaires, Faculté d'Ingénierie Biologique, Agronomique et Environnementale, Université catholique de Louvain, Croix du Sud, 2 bte 7, B-1348 Louvain-la-Neuve, Belgium.
authors.forename: Vesna
authors.initials: V
authors.lastname: Jerkovic
authors.forename: Sonia
authors.initials: S
authors.lastname: Collin
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D005511:Food Handling / Q000379:methods*; D005960:Glucosides / Q000032:analysis*; D027582:Humulus / Q000737:chemistry*; D000077185:Resveratrol; D013267:Stilbenes / Q000032:analysis*; D053719:Tandem Mass Spectrometry
chemical_list: D005960:Glucosides; D013267:Stilbenes; D000077185:Resveratrol; C058229:polydatin