Olive Oil FAQs

Learn about extra virgin olive oil, cooking, health benefits, the best way to store olive oil, how we make it, and more.


1. Why buy in bulk? How long will it last?

Save time, money, and the environment by buying in bulk! Our 3 and 9 Liter refill-at-home containers create a near-perfect environment for olive oil, by eliminating light and oxygen exposure, even once it’s “open”. Keeps your oil optimal for 24+ months! Olive oil is only made once a year, in the fall/early winter, so buying a year's worth of EVOO saves you time, money, and reduces the waste of "one use" bottles. Refill the same bottle over and over again and stop tossing out a bottle every week or two! Believe it or not, there is not an endless supply of sand used to make glass, and only 30% of all glass actually gets recycled. Go one better and re-use!

Prices vary depending on the variety of oil you’re getting, but in general:
The 3L container holds the equivalent of four 750ml bottles / six 500ml bottles (12-24% savings). The 9L holds the equivalent of eighteen 500ml bottles / twelve 750ml bottles (17-34% savings!).

Plus, you'll always have your favorite oil on hand—let’s be real, running out of olive oil is a near kitchen emergency—and you can even share a bottle with a friend, neighbor, or have beautiful olive oil on hand for an impromptu hostess gift!

More details: Made with 100% BPA-free materials. 9L dimensions: 9.5" tall, 7.5" deep (8.75" deep including spout which sticks out 1.25" from box), 10.5" wide. 3L dimensions: just under 12.5" tall, and about 7 x 7" around the base, though it's flexible and can be molded a bit in each direction.


2. Are your 3 and 9 L containers recyclable?

IF plastics beside the hard plastics (#1 & 2) were being recycled somewhere in the world then yes, technically, our Liter bags could be recycled, as they fall in the #7 category of plastics. However, since no one in the world currently recycles anything other than 1 and 2 plastics, the sad answer is no. We stopped putting the "chasing arrows" #7 sign on our bags for this reason, because the reality is they are not being recycled and to label them as such would be "wish cycling," basically false advertising.

When we first switched to the 3 and 9 L containers we had high hopes they would be recycled, but as China stopped accepting American plastics as of 2018, we are trying again to switch course, exploring how to find a #1 or #2 plastic that will work, or an old school metal olive oil tin. The metal tin is a superior choice regarding recycling, and we can top it off with an inert gas when we bottle it, but once it's open customers would have to re-top the container with gas to ensure freshness, and that just seems too cumbersome. It is never simple. The reason we like plastic is it keeps the oil in an oxygen-free environment, which means the oil can stay fresh and usable for up to 4 years—because there is no oxygen to degrade it, and it keeps out all light. This is a huge improvement over the days when olive oil was only optimum for 1 year.

Additionally, plastic weighs considerably less than glass, which means less gasoline/fuel is used in the shipping of our products, so less of a carbon footprint. Lastly, because plastic is considerably less expensive than glass or metal tins on the front, we can offer our products for less, which is always helpful when you are producing a premium item that people traditionally are not accustomed to paying a lot for, as much of what is marketed as extra virgin olive oil is in fact a much lesser product.

3. Can I refill my empty bottles at the Ferry Building?

Waste not want not! Come on by the Ferry Building, refill your bottle and save $3 per bottle, which saves precious resources (did you know that only 30% of all glass actually gets recycled?). We generally have at least seven of our varieties/flavors available. Looking for something specific? Give us a call at 415-765-0405.

4. Do I need to wash my bottle for refills? What’s the best way?

If the inside of the bottle smells like fresh oil and you’ve recently finished it, it should be fine to refill just like that, no need to wash. But if it has sediment or smells musky, it’s best to give it a thorough washing. Some dishwashers do a great job - it’s worth a try!

Otherwise, squeeze 6-8 drops of dish soap into the bottle, add hot water and shake. Next, flush flush flush, until the water runs clear. Drip dry upside-down for an hour or so, then right side up until totally dry, usually 1-2 days. (If you keep the bottle upside-down to dry, condensation will get trapped in the shoulder of the bottle, so it needs to be right-side-up to evaporate. If you have a lid, leave it off/loose until right before you come in and then bring it with you.

DO NOT put a used cork back in - we will provide a new cork at the store. If you're at home, wait at least a week until recorking a bottle - wait until there is no condensation or drips anywhere inside.


5. What is Extra Virgin Olive Oil (EVOO)?

“Extra Virgin” is the highest grade for olive oil, the best. It is always cold-pressed from the first pressing of the olives. Olive oil may be called Extra Virgin if it has less than 1% free oleic acid, and exhibits superior taste, color and aroma. To be a true Extra Virgin it must pass a chemical and an organoleptic analysis.

6. Are your olive oils Organic?

While most of our oils are not currently certified organic, many are in transition (a 3-year process, during which the groves are farmed organically but cannot yet be labeled organic), and all of our olives are grown sustainably with no sprays— pesticides, herbicides, etc—ever used on the trees/fruit. The quality of our products and sustainability is super important to us, and we are excited to be making this official transition.

ALL of the fruit and herbs that are used to make our flavored oils are certified organic, as this impacts the quality of the final product immensely, but because the olives are not yet certified we cannot label them as such.

A few of our offerings are fully certified organic, by choice of the farmers who grow and harvest them, and are labeled as such. We are proud that our Organic Coratina has finally achieved its organic status as well in 2024!


7. Why is your olive oil sometimes cloudy?

One reason our oils can be cloudy is because we usually do not filter our oils. Filtering oils can reduce flavor and body in an oil. We do rack our oils several times after milling (letting the oils sit and settle), which reduces nearly all of the particulate matter and helps clarify the oils.

Our oils tend to be most hazy in the beginning of the year, when they are first pressed and bottled, especially our citrus oils, but oils vary year to year and natural variation is normal. Over time, you may see a thin layer of the tiny olive particles settle out to the bottom of your bottle. This is totally normal too. You can transfer the oil to a clean bottle if you like, once it has settled, if it looks as though there is too much sediment in the bottom. In general, a dusting or thin layer of matter is fine. Anything more than that, we recommend transferring.

You can read more about when to decant your oils here. Some years, if the oil is taking too long to settle out, we will filter it, as having excessive particulate matter in the oil can impart off flavors to the oil.

Another reason olive oils can be cloudy is temperature. If it is winter, and you just got your olive oil, it will likely be cold, and the natural waxes will have suspended. You oil should return to normal in a day or two at room temperature. Again, this is a normal process and does not harm the oil.

8. My olive oil arrived frozen! Does this damage the oil?

It's normal for extra virgin olive oil to solidify or look cloudy when it gets cold (it's actually a good test of whether or not your olive oil IS 100% extra virgin olive oil), so this is very common when shipping during winter/chilly months. Olive oil begins to solidify around 45-50 degrees F. It can look clumpy or lumpy, but this does not negatively impact the olive oil's quality or shelf life. Please just leave it out at room temperature for a few days and it should clarify and return to normal. Do not warm it with hot water or sunlight (heat and UV light ARE things that will damage your olive oil's taste and quality and shorten it's shelf life).

9. What is the best way to store olive oil?

Olive oil should be stored in a cool, dark place. Properly stored, olive oil can keep for at least two years in an unopened container. Olive oil should not be stored in the refrigerator. If chilled, olive oil will become cloudy and eventually solidify or crystallize. Should this happen, the oil is perfectly fine; just leave the oil at room temperature for a time to restore it to its natural state. Buying olive oil in dark green glass further protects it. The four enemies of olive oil are: air, time, heat, and light. It is best to buy only what you will use in 2 months, once opened. The oil will not go bad in this time, but its fresh flavor and scent will fade.

10. How long does olive oil stay good?

It depends on the oil! Olive oil is a fresh product and does not benefit from aging. EVOO has optimum taste and health benefits for anywhere from 12 and up to 36 months after harvest. We harvest October-January each year, and you’ll see a harvest date sticker on the back of each bottle and on every product's page when you order.

How long an extra virgin olive oil will hold up depends on a lot of factors, including it's chemical make-up including polyphenol (antioxidant) levels, acidity levels, whether or not it's filtered, how it's made and how it's stored. We third-party lab test (as well as taste-test) our oils over time to make sure they continue to qualify as Extra Virgin. For example, our Reserve oil from 2012 had a 0.3% acidity when produced and still qualified as EVOO - and was tasty and healthful - 2.5 years later!

Advances in milling have given us oils that clock in at .3% acidity, whereas 25 years ago we were all happy with anything under 1%—so we have "gained time" here with improvements in quality, as well as in packaging, which has become increasingly important as year-to-year the crop now varies widely due to climate change. The years when we have a good crop, we now need to hold oil for the next year, because the next year might be bad or potentially catastrophic. We have one grove, for example, that for most of its life has produced an average of 8k gallons per year that is now down to 5. Why? Less water, more heat. Olive trees are great in that they require less water than most tree crops and can handle a lot of heat, but even they have their limits.

For best flavor, a bottle of olive oil should ideally be used within about 3 months of opening, as, once open, it begins to oxidize, losing freshness, so choose a size bottle that you will use in 3 months.

Our bulk  3L and 10L containers are light and oxygen free, so can hold olive oil fresh for 24-36+ months, that way you just dispense a little at a time, as you need it! These are the best options for long-term storage of oil we have found.

11. How long beyond the harvest date is your olive oil safe to use?

If it has not been opened, it depends on how well it has been stored. If it has been stored well, i.e. the classic cool dark place, then it can stay good for a few years, really. We've opened 4 year old Lemon oil and it was still fresh and delicious; citrus oils tend to last longer. For regular olive oil, it could be equally as long. The best test is to open it and smell it. Does it still smell fresh and grassy? Does it still taste fresh? Then it's ok. If it smells like playdough, wet cardboard, oil paint, or old nuts, that is rancidity. Throw it away!

If it has been opened, it still depends on how well it has been stored, i.e., the dark cool place, but you have considerably less time. The food snob/brat in us wouldn't recommend using a bottle of oil that has been open for more than 2-3 months; the pragmatic Yankee in us might extend that deadline a bit. ;)

12. Should I cook with EVOO?

As long as you are not deep-frying, yes, it is a fabulous oil to cook with, used by millions of people around the world! Our House Blend and OIio Santo EVOOs are all-purpose olive oils, suitable for sautés, sauces, grilling, vinaigrette, as finishing oil, or enjoyed simply with fresh baguette.

The smoke point of EVOO is usually just above 400F, and you can fry at 360, so yes, you can even pan fry with it! The key if you are going to fry in olive oil is to warm the oil slowly in the pan—put oil in a cold pan and heat them both slowly - if you pour olive oil into a hot pan you'll denature it, destroying all the goodness!

That said, we also make and source a handful each year that are more special and expensive due to the careful way they have been grown and produced to have rich, intricate flavor profiles.


13. What are the health benefits of EVOO?

The 7 essential nutrients for good health are: proteins, fats, carbohydrates, vitamins, minerals, roughage and water. EVOO is a fat necessary for human health. The nervous system, hair, skin, and organs all require soluble fats, much in the same way your car requires not only fuel, but oil. Olive oil has many polyphenols, an antioxidant (berries are rich in antioxidants, which is why you always hear they are so good for you). Oleocanthal, which is anti-inflammatory, is one of the primary polyphenols in EVOO, and is what gives it the peppery burn in the back of the throat - the bigger the burn, the better it is for you! Read more about polyphenols (and how to look for high polyphenol olive oils) here.

14. What are the nutritional components of olive oil?

A tablespoon of olive oil contains 120 calories, 14 grams of fat, and no cholesterol. Seventy seven percent (77%) of the fat in olive oil is monounsaturated, and nine percent (9%) is polyunsaturated fat; fourteen percent (14%) is vegetable-derived saturated fat. Extra Virgin olive oils also contain the antioxidants beta-carotene and Vitamin E, as well as the phenolic compounds tyrosol and hydroxytyrosol. Olive oil also contains no salt and is naturally cholesterol-free. While there is no scientific consensus, studies suggest that when substituted for saturated fats, monounsaturated fat lowers blood cholesterol, especially the harmful low density lipoproteins (LDL) while protecting the good high density lipoproteins (HDL).

You can read more about polyphenols and high polyphenol Stonehouse olive oils here.

15. Why is olive oil considered superior to other oils?

Taste is the most obvious difference between olive oil and other commercially popular vegetable oils such as corn, soybean, or canola oils: these oils are tasteless fats. You would not want to eat a piece of bread dipped in vegetable oil for the same reason that many chefs refrain from adding tasteless fat to the foods they prepare. Olive oil, especially extra virgin olive oil, adds a flavor and textural dimension lacking in other oils, making it a suitable substitute for butter and margarine in almost any recipe. In fact, more and more restaurants are serving extra virgin olive oil, both plain and flavored with salt and pepper, as an alternative to butter for bread.

Moreover, vegetable oils are industrial, processed foods. Vegetable oils are generally extracted by means of petroleum-based chemical solvents, and then must be highly refined to remove impurities. Along with the impurities, refining removes taste, color and nutrients.

Extra virgin olive oils are not processed or refined, and are one of the healthiest fats you can find, both in terms of fat composition - it is mostly composed of healthy monounsaturated fats - and because it is chock-full of antioxidants called polyphenols. Read more about polyphenols and Stonehouse's high polyphenol olive oils here. Extra virgin olive oil is essentially fresh squeezed from the fruit of the olive tree, without alteration of the color, taste, and nutrients or vitamins.

16. How does olive oil compare with butter and margarine?

Butter and margarine are essentially fats like cooking oils. A tablespoon of ordinary butter contains twelve grams of fat, of which 8 grams (66%) are saturated fat. In addition, a serving of butter contains 33mg of cholesterol, while olive oil has none! Saturated fat and cholesterol have been linked to increased levels of low density lipoproteins (LDLs) the bad cholesterol. Thus, compared to butter, a serving of olive oil contains much less saturated fat (only 2 grams) and no cholesterol.

The comparison with margarine and the many dairy-free brands is more difficult because the fat breakdown varies by manufacturer and ingredient. Margarine typically contains approximately 10 grams of fat per tablespoon. However, to solidify the vegetable oils used to make margarine and dairy-free options, the oils have to be hydrogenated. In the hydrogenation process, trans-fatty acids are created. Trans fats have a double whammy effect of increasing LDLs, the bad cholesterol, and lowering HDLs, the good cholesterol. It is well studied that diets rich in trans fats increase your risk of heart disease. Eat good fat!

17. Can olive oil be used to replace butter, margarine or vegetable oil in recipes?

Yes, please! Olive oil can be used in place of butter, margarine or vegetable oils like canola in many recipes, such as on vegetables, rice, potatoes, for baking, on toast - just about anything!


Click here to browse Stonehouse Recipes by Product or Type of Dish!


Olive Tree FAQs

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