Olive Center Offers Chemical Testing
The UC Davis Olive Center is now offerÂing olive oil chemÂiÂcal and senÂsory evalÂuÂaÂtions, includÂing tests for DAGs and PPP, which are unique to the U.S. labÂoÂraÂtory. The deciÂsion to offer these analyÂses was driÂven by requests from proÂducÂers, retailÂers, and importers, with the goal of proÂvidÂing more descripÂtive terms for olive oil qualÂity beyond the stanÂdard IOC/USDA tests.
The UC Davis Olive Center announced that it is now offerÂing olive oil chemÂiÂcal and senÂsory evalÂuÂaÂtions. Included among the choices of chemÂiÂcal analyÂses are tests known as DAGs and PPP. UC Davis is the only labÂoÂraÂtory in the U.S. proÂvidÂing these parÂticÂuÂlar chemÂiÂcal indiÂcaÂtors of olive oil qualÂity, said the cenÂter’s direcÂtor Dan Flynn.
The deciÂsion to offer chemÂiÂcal analyÂses was driÂven by requests from proÂducÂers, retailÂers and importers, accordÂing to Flynn.
Flynn stated that most oils pass the International Olive Council (IOC) and United States Department of Agriculture (USDA) chemÂistry stanÂdards for extra virÂgin even though senÂsory tests fail the same oils for ranÂcid and fusty flaÂvors.
A 2010 UC Davis Olive Center report indiÂcated that the IOC/USDA chemÂiÂcal stanÂdards would be more effecÂtive if they included the newer chemÂiÂcal stanÂdards adopted by Germany and
Australia that meaÂsure DAGs (1,2 diaÂcylÂglycÂerol) and PPP (pyropheoÂphytins) levÂels and corÂreÂlate well with senÂsory tests.
The UC Davis Olive Center offers the DAGs/PPP test as well as other chemÂistry and senÂsory tests.
The senÂsory tests have been offered for about eight months, said Flynn. He indiÂcated that the cenÂter’s tests proÂvide more descripÂtive terms than the IOC/USDA senÂsory tests. For examÂple, the IOC/USDA requires testÂing the fruitiÂness of an oil. The Olive Center tests will furÂther elabÂoÂrate on the charÂacÂterÂisÂtics of fruitiÂness, with descripÂtive terms such as, floÂral, green apple, green almond or banana.
Sensory panÂels conÂtain at least eight trained tasters. Many of the testers have been on panÂels for as long as ten years while othÂers are apprenÂtices with more than two years expeÂriÂence. The testers genÂerÂally meet weekly but Flynn said that the goal is to get results quickly to proÂducÂers and if the demand is there, the senÂsory tests may be schedÂuled more freÂquently.
Results of chemÂiÂcal and senÂsory tests are conÂfiÂdenÂtial but data (withÂout proÂducer names) may be colÂlected for research purÂposes, noted Flynn.
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