(Disclosure: I received a discount on the International Food Blogger Conference (IFBC) registration fee in exchange for writing three posts about my experiences at the conference. All opinions are my own.)

This is part 1 of a 2-part series on a visit to an olive grove and olive oil processing facility in Yolo County, California.  The second part will appear soon.

“I absolutely love these trees,” mused Peter Hunter of Longview Ranch in Winters, California. Standing in a grove of 10 year old olive trees with a group of IFBC attendees, I could see why he might feel such strong emotion — the myriad green hues of the leaves and the gentle sound of the wind through the branches was lovely for the eyes and ears.  It was close to harvest time and trees were studded with pale green olives — some so dense that they bent the branches.

This was the first stop on our pre-conference “Olive Oil Excursion,” snacks and beverages in the early evening while we learned about olive farming from Mr. Hunter, Adam Englehardt from Cobram Estate (an Australian company that recently launched U.S. operations), and various other farm and Cobram representatives.  As a food and farming nerd, I found it fascinating to hear about olive growing in California, how olive oil is produced, and how California is maintaining world-class quality standards.

Being Late Offers Advantages

California is relatively new to the global olive oil scene.  To be sure, olive trees have been in the state since the early years of the Spanish colony (you’ll probably find olive presses at the historic California missions), but until about 30 years ago, the vast majority of California olives were used for canning.  And so, when the state’s new olive oil pioneers started going big, they started with a blank slate. They planted trees that would be best suited for California’s climate and soil, planted them easy to harvest rows on relatively flat terrain, and built new processing plants near the groves.  The growth has been impressive, but currently California supplies less than 5% of the extra virgin oil used in the U.S.

The olive grove where the food bloggers gathered was row after row of young 15-foot tall trees on flat land, a far cry from the romantic vision of gnarled ancient trees sprawling across the rolling hills of the countryside, but this planting strategy — Hunter called it “medium-high density” — offers some key advantages.

One of the biggest advantages occurs at harvest time. The “mature green” olives that make the best olive oil cannot be shaken from the tree — their “retention force” is too high — so mechanical or hand harvesting is necessary to gently strip the fruit from the branches with minimal damage. This is a lot easier on fairly short, well-pruned trees in even rows.

Retention force is a big problem for European olive growers, our hosts said, because many of their trees (millions!) grow on hilly terrain that is unsuited for machines, and it is hard to find enough people to hand pick the olives. Consequently, some farms let the fruit get ripe enough to be shaken, which allows the fruit to ripen past its ideal “mature green” state. The resulting olive oil is substandard but might still be labeled extra virgin.

High Quality Olive Oil Requires Quickness

Another big advantage of high density planting is quickness.  Olives can be harvested quickly and rapidly transferred to the processing plant.  Freshness is absolutely critical — the ideal time to press olives is immediately after harvest — so farmers, harvesters, and producers work together to

• Identify the best harvest time – I chatted with one of Cobram Estate’s interns in the grove, and she told me that one of her projects is to visit groves that supply olives to Cobram Estate. She collects olive samples, brings them back to the Cobram laboratory, where she checks their ripeness level, the oil content and other things. With these results, she and her colleagues can estimate the best harvest time for each grove.  The analysis can also help farmers maintain their trees — for example, one part of a grove might be lacking nitrogen, another might be getting the wrong amount of water.
• Quickly pick the crop — mechanical harvesters or groups of skilled human harvesters are deployed to the groves when they are near their peak.
• Rapidly transport the crop to the processing plant — olives are sourced from farms close to their processing plant.
• ASAP processing — during the olive harvest, processing plants are probably running 24/7 and the logistics experts are keeping up-to-date schedules of olive deliveries so that the olives don’t wait around for processing.

The Meaning of Extra Virgin Olive Oil

In the olive oil industry, extra virgin means something. Although some producers use the term without justification (see, for example, the numerous pieces about olive oil fraud), California producers have a specific definition.  California Department of Food and Agriculture regulations define extra virgin oil as

…olive oil that has a free acidity, expressed as free oleic acid, of not more than 0.5 grams per 100 grams, a median of defects equal to 0, and the other characteristics which correspond to the limits fixed for this grade in these standards. Extra Virgin olive oil is fit for consumption without further processing.

These characteristics are determined by a combination of laboratory analysis (for things like free oleic acid content) and panels of trained olive oil tasters (they check for defects like fustiness, mustiness, rancidity).

Tips for Buying, Storing and Using Extra Virgin Olive Oil

If you want to enjoy extra virgin olive oil at its best, here are a few tips for buying, storing and using it:

• Freshness is everything — experts often liken olive oil to fruit juice: it’s a fresh product with a limited shelf live.   Some producers (especially those in California) are putting a harvest date on the bottle so you know exactly when it was processed.  Olive oil is best within 12-18 months of the harvest date.
• Look for the labels — California has its olive oil act together:  solid certification programs are in place to ensure that bottles labelled “extra virgin” pass laboratory and sensory tests (i.e., human taste testers).  The two key groups are the California Olive Oil Council (a trade association) and the Olive Oil Commission of California (a check-off program administered by the California Department of Food and Agriculture). Bottles that carry their labels (shown below) meet extra virgin standards. Spanglish Spoon has an informative piece about How to Spot Good Quality Olive Oil with many more details on the certification programs.  I am not aware of such standards in other countries, but they probably exist.
• Use quickly once opened — when you crack open a new bottle, and every time you open it again, fresh air rushes in.  The oxygen in the air slowly reacts with the oil, reducing its quality. After you open the bottle, try to use it within a few months.  Buying smaller bottles might be a good idea (that 1 gallon bottle might have seemed like a good idea when you bought it, but not when it starts to taste funny before you can use it up).
• Store your oil in a cool, dark place — don’t store in a bright or warm place (like next to your oven or on the kitchen counter), keep it in a cool, dark cupboard. (One of the first things I did after returning from Sacramento was move my olive oil from a cupboard next to the oven to the other side of the kitchen.)
• Avoid the “too good to use” trap — Sometimes, foods that we buy on vacation — like a bottle of olive oil from a vacation in Tuscany or Davis, California — become “too good to use,” and end up going bad because the right “special occasion” never appears.  Don’t let this happen to you:  use that special Tuscan or Davis olive oil to celebrate small achievements at work or your favorite sports-ball team winning a game.  And let your digital photos stimulate fond memories of the trip.  (I have a few bottles of wine that have suffered the “too good to use” fate).
• Have “use it up” recipes — have a few ‘use it up’ recipes in your collection. Two of my favorites are a sherry and olive oil pound cake in Alice Medrich’s Pure Dessert (uses 1 cup) and the Jerusalem olive oil cake with orange marmalade and almonds in Sara Perry’s Holiday Baking: New And Traditional Recipes for Wintertime Holidays (uses 1/2 cup).

In the near future, I’ll post part 2 of this series, which will take you into an olive oil processing facility to see how an inedible green olive is turned into extra virgin olive oil (and will include a flowchart!).

Other Olive-Related Posts from IFBC excursion attendees
Everything You Need to Know to Find the Best Olive Oil by Gold Country Cowgirl
Olive Oil Carrot Cake by Serena Lissy
How to Spot Good Quality Olive Oil by Spanglish Spoon