California Olive Oil News^©
A Publication of The Olive Oil Source  

Volume 7 Issue 12

December - January  2004-2005

The fourth annual Sonoma Valley Olive Festival started with the blessing of the olives at the Mission San Francisco Solano de Sonoma December 4th. Events run through February 26-27.  There are dozens of promotions and activities ranging from pairings of olive oil and wine at local wineries, olive oil milling, a martini competition, olive art exhibits, etc.  Festivities end with an olive themed Artisan Market.  For a full listing of events look at the events section in this newsletter or go to www.olivefestival.com. 

This year the blessing was given by Father Aurelio Villa after presentations by Wendy Peterson of the Sonoma Valley Visitors Bureau, Ed Stolman of the Olive Press and Gabrielle Leonhard of the Mission Olive Preservation, Restoration, and Education Project (MOREP).

Attendees mingled after the service in cold but sunny weather, listening to the music of a Mariachi band. MOREP had displays and encouraged purchases of trees and olive oil to support their project.

An Olive Harvest Tasting was held in the plank-floored second story of the adobe Barracks building built in 1851.  Vendors offering tastings  included Jacuzzi family winery, L'Olivier, The Olive Press, MOREP, Don's Olives and others.

Several other Sonoma businesses celebrated the beginning of the festival with special events.  B.R. Cohn Winery in Glen Ellen had olive oil tasting at the wine bar and tours of their 130 year old Picholine trees. 

Schug Estate Winery poured their estate wines and hosted Catherine Farrell of Napa Tapas who offered tastes of her olive tapenades and olive oil.

Catherine Farrell of Napa Tapas

Flying First Press

The Olive Oil Source has shipped and delivered a record number of First Presses this year.  While there are now First Presses on most of the world's continents and in most of the olive growing areas of the world, the vast majority end up in California.  If not shipped, customers pick up the presses in pickups, Suburbans, trailers, and some have even been squeezed into tiny hatchback sedans. 

Recently customer Dick Goodman of Arizona showed up with his private plane to pick up a press.  The First Press weighs about 350 lbs and is not exactly compact so getting it into a twin prop plane along with two passengers and a large dog was a challenge. Dick, a man of many talents, currently owns an automotive accessories manufacturing business.  Olive oil making seems to be his next venture.  The press finally made it on board after complete disassembly.

Several web visitors have emailed with chemistry comments and questions relating to freezing olive oil: What are the clouds in my olive oil, will olive oil freeze in the refrigerator and does the way it freezes say anything about its quality?

Refrigerator temperatures are preset to around 37 degrees F by most manufacturers. Chemistry texts list the freezing point of pure oleic acid at around 39 degrees F. Olive oil manufacturers don't generally list a freezing temperature because it is very variable depending on the olive variety and ripeness of the olive at processing. Unlike the properties of an element or simple compound like H2O, olive oil is made up of hundreds of chemicals, many of which change with every pressing.

Like most fruit, olives have waxes on their epidermis (epicarp) to protect them from insects, desiccation and the elements. These natural waxes are what allow an apple to be shined. If an oil is sent to a cold climate or will be used in a product like salad dressing where it will be stored in the refrigerator, it is often "winterized". The oil is chilled and filtered to remove the waxes and stearates. A standard test to determine if olive oil has been sufficiently winterized is to put it in an ice water bath (32 degree F)  for 5 hours. No clouding or crystals should occur.

Oil which has not been winterized will clump and form needle-like crystals at refrigerator temperatures as the longer chain fats and waxes in the oil congeal, but the oil will not usually harden completely unless chilled further. Some olive varieties form waxes which produce long thin crystals, others form waxes which congeal into rosettes, slimy clumps, clouds, a swirl of egg white like material, or white sediment which the consumer may fear represents spoilage.  These visual imperfections may form outside the refrigerator during the winter when oil is exposed to cold temperatures during transport. Chilling or freezing olive oil does no harm and the oil will return  to its normal consistency when warmed.

The ideal temperature to store olive oil to reduce oxidation but to avoid clouding  is around 50 degrees F.  

To determine the actual freezing temperature I put some oils in the freezer with a thermometer. At 40 degrees most of the oils had not hardened or formed any crystals. At 35 degrees F most were firm enough that they could not be poured but were as soft as butter at room temperature. As the temperature lowered, more components of the oil solidified. At 10 degrees F the oils were hard enough that a fork could not penetrate them. Determining at what point to call the oil "frozen" is a matter of semantics. This slow increase in hardening as the temperature is lowered is in sharp contrast to a pure substance such as water which switches from a liquid to solid phase at an exact temperature.

Eric from Montreal writes that he has heard that to determine whether an olive oil is Extra-Virgin, place a small quantity of the oil in a glass bowl and refrigerate it for a few days. If it becomes crystalline, the chances are good that it is a true extra-virgin olive oil. If it forms a block, it is most likely chemically refined oil that has had some first-pressed oil added to it.

I don't think this is a valid observation. While refined or pomace oils will usually be stripped of their waxes and it is more common for a refined oil to be winterized to be used in a cheap dressing, many excellent extra virgin oils do not form "crystals". I have watched the production process of many premium oils from olive to bottle and they form a solid block when frozen. Unfortunately, detecting fraud is more difficult than just freezing the oil.

Olive Tree Restoration at Vallejo Home in Petaluma, California

Mission Olive trees grown from cuttings from an ancient 200 year old grove planted by the Padres and Native Americans were blessed by Sonoma's Franciscan Padre, Padre Aurelio Villa at the blessing of the olives event in Sonoma December 4th.  The olive trees are part of a restoration project at the General Vallejo Home in Petaluma which will include pruning of existing trees and planting of new trees to replace some of those lost from the gardens over the years.

The Mission Olive Preservation, Restoration and Education Project (MOREP) and the California State Parks are conducting the project to preserve and restore the historic Mission olive trees .  The 125+ year old olive trees planted in the gardens and in the picnic area behind the "chalet" will undergo sustainable restoration so that they do not continue to fall as many of the older trees have done.  The canopy has become so heavy that limbs are intertwined and were causing severe breakage last winter.  This is not only unhealthy for the trees, but could be a safety hazard.

Volunteers are needed to assist in the preparation and cleanup of the pruning which will be conducted by volunteer professionals from olive tree growers in the Sonoma Valley.  For more information call Ron Chapman of MOREP at 707-996-8984.
 

Padan Asks: What does the olive pit contain with comparison to the fruits? If we had the option of making the oil without using the pit - is it good thing to do? (oil within, bitterness ext.)

Olive Oil news replies:  The fruit is technically a drupe with three parts; the epidermis (epicarp) which remains green throughout the growth phase then turns purple and brown when ripe, the fleshy part (mesocarp) which contains the oil and the stone or pit (endocarp) which holds the seed. The pit is primarily lignin, a component of wood, with very little oil or flavors. There is some debate in the industry if the pit contributes any oil during processing.

When oil was primarily produced with hydraulic presses, the pit fragments were important in keeping the olive paste on the mats. Today most large oil producers use centrifugal machinery and the pit provides no particular advantage or disadvantage to the processing.

There are olive oil companies which pit the olives before extracting the oil. They claim a better tasting oil but in California these oils have not distinguished themselves in blind competitions such as the L.A. county fair.