What We Do

The UC Davis Olive Center promotes collaboration between UC Davis, olive producers, and the community. The university’s relationship with the olive industry began a century ago with the development of safe canning methods for California olives. This collaboration has also produced research into new olive cultivars, mechanical harvesting, olive fruit fly control, olive oil processing, and sensory evaluation of olive oil. The UC Davis Olive Center brings together North America’s leading authorities on olive oil and table olives.

Below is a list of on-going UC Davis Olive Center research projects and their current status.  Please contact Nicole Sturzenberger at the olive center with any additional questions, ndsturzenberger@ucdavis.edu

FOR MORE INFORMATION ON GROWING OLIVES, PLEASE CONTACT YOUR COUNTY'S FARM ADVISOR.

UC ANR Cooperative Extension

OLIVE TREES

Organic management of olive orchards.   With the assistance of farm advisor Paul Vossen and consultant Alexandra Devarenne, Dan Flynn oversaw the donation and planting of 600 new olive trees at UC Davis. Flynn, experienced in organic agriculture, will oversee the organic certification of the new orchards and is working with Extension Specialist Karen Klonsky to study organic methods as applied to super-high-density orchards.  Status:  Dan met with inspectors from California Certified Organic Farmers in Fall, 2008 and is now keeping records of orchard inputs so that the orchards can be certified organic in about two years.

Disease-resistant olive rootstock.   The olive center will seek to conduct joint research with the Institut de Recerca i Tecnologia Agroalimentaries (IRTA) in Barcelona on verticillium-resistant olive rootstock.    The olive center has been in discussions with California olive tree nurseries to provide matching funds for the project and with the Department of Plant Pathology to lead the project.  Status:  In April 2009, the Department is developing a proposal for testing super-high-density olive tree clones that have been in verticillium-infected soil for three years.  Foundation Plant Services has imported olive trees grafted to verticillium-resistant rootstock from IRTA and has initiated the quarantine period. 

Olive tree research fund.  The olive center is in discussions with nursery leaders to develop a fund dedicated to olive tree research.  Status:  Discussions are ongoing.

TABLE OLIVES

Mechanical harvesting for table olives.  Dr. Louise Ferguson has been engaged in a five-year study of methods to mechanically harvest black-ripe olives in a conventional orchard. The study is funded by the California Olive Committee under a USDA marketing order.    In addition, Dr. Jean-Xavier Guinard is working with Dr. Louise Ferguson on sensory research comparing mechanically harvested black-ripe olives with hand-picked olives.   Status:  Research is ongoing.  For more information, see HTTP://groups.UCANR.org/olive_harvest  In June 2008 a graduate student working under the direction of Dr. Guinard, Soh Min Lee, led a trained taste panel in tasting black-ripe olives harvested by hand and those harvested mechanically.  The panel found that processing variations were more significant factors in affecting sensory attributes than the method of harvest. 

Specialty table olive research.   Dr. Maria Marco, a new associate adjunct professor in the Department of Food Science and Technology and an expert in fermented foods, will be delving into the science of fermented olive products, with a tour of the major processors slated for February 2009.   Status:   The February tour identified a number of potential research projects, including examining processing defects, economic and environmental considerations for processors, and scientific analysis of common processing methods.   As of April 2009 Dr. Marco and the Agricultural Issues Center are preparing proposals to address these issues. 

Table olive sensory research.  Dr. Guinard has led a study of sensory attributes and consumer testing of California black-ripe olives and imported black-ripe olives, funded by the California Ripe Olive Coalition.  Status:  In April 2009, Dr. Guinard and Soh Min Lee expect to release their study comparing California black-ripe olives to imported black-ripe olives.

Olive fly control.  A number of studies are underway to develop effective methods of controlling the olive fruit fly, the most serious pest for olives in California and in the Mediterranean nations. The studies primarily are funded by the California Olive Committee, which administers the federal marketing order for black-ripe olives.  Status:  Research is underway on a number of fronts, see http://www.olivecenter.ucdavis.edu/publications for information on past studies. 

Black-ripe processing.   The California Olive Committee has requested research into enhancing the nutritional qualities of black-ripe processed olives.  Status:   In February 2009, the Committee funded a project led by Dr. Alyson Mitchell that will examine the impact of replacing one of the polyphenols that is commonly removed during processing to enhance the nutritional properties of black-ripe olives.

OLIVE OIL

Olive oil labeling legislation.  Governor Schwarzenegger signed SB 634 (Wiggins) which requires olive oil to be labeled consistent with  international grade standards.  The olive center provided technical support to the California Olive Oil Council on the drafting of the legislation.  The law went into effect on January 1, 2009.  Status:  In January 2009 Dr. Travis Lybbert and graduate student Christopher Gustafson published a paper in the journal of the Gianni Foundation of Agricultural Economics which discussed the new law http://www.olivecenter.ucdavis.edu/Gustafson%20%20Lybbert%20-%20Olive%20oil.pdf

Super-high-density survey.   The olive center has conducted a survey of super-high-density olive growers to assess the orchard practices and size of the industry.  Status:  The survey should be released by May 2009.

Olive oil processing.   In September 2008 the center acquired olive oil milling equipment from Alfa Laval.  Alfa Laval sent a consultant from Italy to assist in plant’s start-up in December.  Ultimately the center hopes to attract contributions to establish a permanent processing facility that would be built at the Robert Mondavi Institute.  Status:  In March 2009, architects designing the August Busch III Brewery, Winery and Food Processing Facility at the RMI modified the plans to accommodate the olive milling equipment.  The design modifications will place the delivery hopper and olive washing components outside the building to encourage processing efficiency and sanitation.  The modifications of the facility design require an additional $57,000, which so far is not funded and will require the help of a donor or donors.  

Olive oil sensory panel. Dr. Jean-Xavier Guinard will begin screening and training panelists in 2009 and intends to seek accreditation by the International Olive Council for a fee-for-service olive oil taste panel. The panel also will conduct research on olive oil sensory profiles.  Status:  Dr. Guinard intends to develop a training plan in Spring 2009.

Olive oil adulteration.   The center began exploring a partnership with the UC Davis Genome Center to conduct sophisticated chemistry analysis to combat olive oil adulteration, submitting a proposal to a potential donor for a $200,000 two-year research project. If funded, world-renowned lipids expert Dr. Ed Frankel will head up the project in collaboration with Dr. Oliver Fiehn of the Genome Center and Dr. Alyson Mitchell of the Department of Food Science and Technology.  Status:  The research proposal has been scaled back to a one-year proposal and will be resubmitted to the potential donor in April 2009.

Olive oil mill waste management. Under the direction of Nicole Sturzenberger, the olive center has been exploring the potential of using olive mill waste for biomass and plastic polymers. Dr. Ruihong Zhang of the Department of Biological and Agricultural Engineering, Dr. Sharon Shoemaker of the California Institute for Agricultural Research and Dr. Peter Green of the Department of Civil and Environmental Engineering have done initial work in these areas, and 2009 will look more closely at the funding viability for further research.  Status:  The research is ongoing, but has not attracted industry funding as of yet.

Olive oil industry survey. The California Olive Oil Council has requested that the olive center update a 2004 survey of the olive oil industry in California.  Status:  The survey will be conducted by Nicole Sturzenberger beginning in Spring, 2009.

Olive oil sensory and consumer research. Dr. Jean-Xavier Guinard is providing the first sensory and consumer examination of olive oils. The research will evaluate more than 20 olive oils from California and around the world, offering valuable insights for California producers into consumer preference.  Status:  The study is underway and will be completed by June 2009.