Mr. Crumbs sent me an article last month that made my jaw drop. After reading it, I felt cheated and deceived. It was tempting to copy and paste the whole thing for you guys to read, but instead I set it aside specific for today’s post.
According to the article, the U.S. Pharmacopeial Convention (USP) told ABC news that one of the easiest foods that can be tampered with is olive oil, since it can be diluted with cheaper oils and we as consumers won’t know the difference.
Another commonly altered food was lemon juice, where researchers found as little as 15% and 25% lemon juice in bottles labeled 100% pure lemon juice. YIKES!
The article made me wonder… what if the olive oil we buy is really only 15% olive oil? What if the rest of the jug is filled with the icky “yellow vegetable oil” that we’ve been striving so hard to avoid?
And then my next thought made me slightly angry: Am I REALLY paying a premium price for a no-nutrition oil that’s being masked as a higher quality product because it’s in a fancier bottle?!
Fortunately there’s a very simple test to ensure our olive oils really are made with olives, and they’re not being diluted with lesser quality imposters.
Remember from Monday how olive oil is liquid at room temperature yet solid when refrigerated? And remember from early in our Truth About Fat series that polyunsaturated oils (the yellow vegetable kind) are liquid at both room temperature AND when refrigerated.
Those are the standards by which we judge: whether or not it turns a solid!
Two Step Olive Oil Purity Test
- Pour 2-4 tbsp of olive oil into a clean glass jar. Seal the jar.
- Put the jar in the refrigerator for 24 hours.
- If the oil solidifies, it’s monounsaturated and is olive oil.
- If the oil remains a liquid, it is polyunsaturated and is NOT olive oil.
Three different brands of olive oil have come through my front door so far this year, so I took a small sample of each of these oils and ran it through the test above. Curious about the results? First, let’s talk about the oils.
Contender #1: Costco
Costco’s prices are very competitive, and their products are usually good quality. Naturally this is a place to go for something you want to be good, yet affordable (and don’t mind having a lot of). $11.49 for a 2 liter container.
The Statistics:
- Extra Virgin Olive Oil.
- Labeled “first cold pressed.”
- No harvest date, but has an expiration date of February 7, 2014 (purchased March 2013)
- Dark, opaque plastic container.
- Stored in a closet where the temperature is always approximately 68 degrees.
- No mention of NAOOA on the bottle.
Contender #2: Olitalia
This bottle was a Grocery Outlet find and experiment. I had never heard of this brand (despite the bottle saying “the olive oil brand most distributed in the world”), but we needed olive oil and I had a coupon. $6.99 for a 1 L container.
The Statistics:
- Extra Virgin Olive Oil.
- Labeled “first cold pressed.”
- No harvest date nor expiration date. Contains Lot number and time stamp.
- Dark, opaque glass container.
- Stored in a closet where the temperature is always approximately 68 degrees.
- No mention of NAOOA on the bottle.
Contender #3: Trader Joe’s
Trader Joe’s carries a few different varieties of olive oil. This one was simply the cheapest on the shelf – $5.49 for 1 liter, and I bought it for two reasons: a) per liter, the price beat out Costco, and b) it’s a lot easier to pour oil from a 1L container than a 2L jug.
The Statistics:
- Extra Virgin Olive Oil.
- Labeled “cold pressed.”
- Harvest date/expiration date unknown (I accidentally recycled the bottle 🙁 )
- Medium, opaque glass container.
- Stored in a closet where the temperature is always approximately 68 degrees.
- NAOOA data unknown (darn that recycle bin!)
The Two Step Olive Oil Purity Test:
I poured 2 ounces of each oil into separate glass containers and put them in the fridge, on the top shelf, at the very back, Saturday after dinner.
The Result:
After 12 hours, two of the three oils had completely solidified. I was surprised to see one oil still liquid, so I kept the oils in the fridge until evening.
After 24 hours, all three oils had completely solidified. Which one took longer than the others?
Costco.
This doesn’t mean Costco’s olive oil is bad or even watered down with other oils that aren’t derived from olives. It did – after a full day – solidify. But there is no explanation why it took twice as long to get to the same result. I even re-arranged the line-up of the jars in the fridge, thinking that their placement had something to do with it (although they were at the very coldest spot in the fridge… beef on the same shelf nearly froze during the test).
The oil being “old” doesn’t explain it either, since I had bought it early March and opened the container just for the experiment – I haven’t even really used it yet!
Now What?
Honestly, my gut tells me to return the Costco olive oil. Given the simple and consistent standards of the test, it should have passed just as easily as the other oils.
Another reason I’m returning the bottle is because I’m making a commitment to no longer cook with olive oil at high temperatures. We’ve been good about it for the past couple months, but I want to be even more so going forward. This means that opportunities to use 2 liters of olive oil are going to be far less.
Going forward it would be better to buy the smaller 1L glass jars of olive oil from Trader Joe’s, even if I have to buy two at a time. Another option would be to continue trying out random brands from Grocery Outlet. They’re prices are competitive, but now that I know what to look for (using these guidelines for buying), I can be even more discerning on the quality of oil. The Olitalia oil was actually really tasty!
UPDATE: Just a few weeks after this post was published I sifted through all of the the data left in the comments below, and even more. Read the science (and non-science) and determine for yourself whether or not the fridge test is valid!
Where to find Quality Olive Oil
Considering from the test I ran that Costco olive oil may not be the best. And not everyone has a Trader Joe’s or Grocery Outlet, you might need some ideas on where to find good olive oil! Use your price book to compare prices at your local stores.
If you prefer online shopping Amazon has some good options as well as Thrive Market. I trust the brands at Thrive Market to be solid sources. Amazon is a little riskier unless you are sure to research the brand you buy.
Tonya F.
Thank you for this information. This topic caught my eye because just this week I went to my local health food store for groceries and they were out of my normal Organic Extra Virgin Olive Oil (Field Day). So I purchased a different brand (Flora). I kept getting aggravated because I would pack some of the Flora olive oil and balsamic vinegar in my lunch, and unlike Field Day’s oil, when I would get this one out of the fridge it had solidified making it difficult to use for dipping.
I haven’t done the exact 2oz test in glass for 24 hours as you suggested but this was enough to notice there were obvious differences and now I know why, thanks to your post. I guess my forced purchase of a new brand of olive oil was a blessing in disguise. 🙂
Kelly H.
Woohoo! I don’t have to test mine because you already tested it for me! 🙂 I get Trader Joes olive oil. Now I will keep getting that when I run out.
Corey Jewett
Tiffany: The fridge test is inaccurate and misleading. Other oils (like canola and peanut) have enough monosaturated fat that they will at least semi-solidify in the fridge. (I don’t own any canola oil, so I can’t verify this.) See: http://www.truthinoliveoil.com/2013/04/truth-on-olive-oil-health AND http://www.aromadictionary.com/EVOO_blog/?p=550
As for why some oil would take longer to solidify, again it has to do with the ratio of monosaturated fat. When you get down to it, olive oil is a crop. It will vary depending on growing conditions, varietal, harvest time, etc.
Blair Massey: Actually, the Consumer Reports article I believe you are referring to (http://www.consumerreports.org/cro/magazine/2012/09/how-to-find-the-best-extra-virgin-olive-oil/index.htm) is specifically for the Kirkland Signature Toscano oil, not the organic one.
I haven’t read Tom Mueller’s book Extra Virginity (http://www.truthinoliveoil.com/extra-virginity), but there are some helpful resources on his site:
http://www.truthinoliveoil.com/great-oil/how-to-buy-great-olive-oil/
http://www.truthinoliveoil.com/2012/09/toms-supermarket-picks-quality-oils-good-prices
Specifically on the topic of Costco’s olive oils he says: “Costco Kirkland Toscano – Kirkland is the Costco store brand. I’ve been disappointed by Kirkland Organic EVO (not to mention the “extra virgins” in multi-liter plastic jugs), but the Toscano signature oil is the real deal.”
Tiffany
Hi Corey,
I’m going to revisit this issue again next week. The information you and other readers have shared is definitely worth reading and I want to have the opportunity to give it my full attention. I’ve also read some really great research on the topic, but right now it’s like a tangled ball of string in my head. I want to lay out the thoughts so that they all make sense (even to me!) so that we’re all more educated! ~Tiffany
Pam
I ALWAYS use organic virgin coconut oil for all eating and cooking.
The safest and best there is and with all the health benefits other oils can only dream of. I buy it in 5kg lots to make it economical.
Hemp Seed oil far superior to olive oil for making mayonaise etc.
If something is too expensive use it more frugally is my motto but get the best.
Eileen @ Phoenix Helix
Tiffany, I’m sorry but the fridge test is a myth. This website explains why: http://www.aromadictionary.com/EVOO_blog/?p=550 . If you want to know if your olive oil is the real thing, look for the COOC seal (tested for purity) or do your own taste test at home. Open the bottle, close your eyes, and smell. It should smell vibrant and wonderful. Next, pour some in a little glass, and take a taste. Roll it around on your tongue. You should be able to taste the olives, there might be some bitterness or pepperiness at the back of your throat. What you shouldn’t taste is anything greasy, moldy, rancid or reminiscent of cardboard. It also shouldn’t be a neutral tasting oil.
Tiffany
Eileen,
I mentioned to Corey, but I’m going to revisit this issue again next week. The information you and other readers have shared is definitely worth reading and I want to have the opportunity to give it my full attention. I’ve also read some great research on the topic, but right now it’s like a tangled ball of string in my head. I want to lay out the thoughts so that they all make sense (even to me!) so that we’re all more educated! Thanks for sharing your point of view! ~Tiffany
Olinda Paul
I do NOT buy any Italian based oils or distributed by Italy as most of them are FAKE and do not solidify in the fridge. I have also used oil from Greece and the Ukrane…they do the same to their oils. I have even used a local olive oil company in California called STAR. Here is their response to my questions:
They use 100% olive oil. If so I asked why doesn’t it solidify. Because the use “different” types of olives to make one blend. Which seemed to make sense to me for a moment. Then if they use different oils, some types of olives don’t have as much oil properties? Harrumph….and I say this because being Portuguese, my grandparents on both sides made their own olive oils, each using a different type of olive tree. After pressing the oil was kept in a dark closet with a very dark bottle and it was revered. When put in the fridge it definitely became solid. I am not an expert but olive oil doesn’t even TASTE the same as I remember. Also, it was much more oiler and more flavorful than we see in the stores. It’s all about the money they can make at the end of the day. Sad really. You can call the companies while at the grocery like I do. It’s powerful when you say…well then, I don’t think I will buy this brand.
Tiffany
Olinda,
Wow! Your personal experience puts a new spin on olive oil. Olive oil SHOULD taste distinctly like olives – kinda like coconut oil tastes like coconut! How interesting that your grandparents made their own. It would be such a treat to try a homemade version!
Star was one of the brands I was wanting to try, but just didn’t have the opportunity to. Thanks for letting us know how your experiment turned out. It is very sad that the quality of our food has become lesser important than the bottom line profit. 🙁 Thanks for sharing! ~Tiffany
kirsten@FarmFreshFeasts
Tiffany,
Thanks for posting this! I’ve got both the Costco Organic (not yet opened) and regular Olive oils (about half gone) and I’m glad to test and get back to you with my results for the organic once I open it. I hate to waste, so I will use the rest of the bottle that’s open first.
I mainly use it in pizza–and bake that at a high temp–so I am curious.
Appreciate it!
Tiffany
My pleasure Kirsten! We’ve made pizza dough both with and without the oil and didn’t notice much of a difference, so we now go without. You guys eat it as often as we do, so it’s definitely something to put on the radar. I look forward to hearing your results! ~Tiffany
Katie @ Kitchen Stewardship
Kristen,
Baking with EVOO is not a big deal – nothing gets hot enough to be over 350 – think of the “done” temp of a chicken after hours (180F) or bread (220). EVOO should be fine.
🙂 Katie
Tiffany
Thanks for chiming in Katie! Good to see you in my neck of the woods!
One thing I do want to throw out there is baking with a stone. Our pizza stone was designed to withstand high temperatures (800-900F is not uncommon), and since our pizzas cook directly on that stone, the possibility of compromising the integrity of the oil at that temperature seems even greater. I can’t know for sure the temperature of the pies, but just something to consider if you use a stone as well. ~Tiffany
Tessa@The Domestic Diva
Featuring your article this week on Allergy Free Wednesday!
Tiffany
Awesome! Thanks Tessa!
Trisha
Wow! Thank you for sharing. I’m testing our olive oil TONIGHT. I didn’t know that it could be tampered with. I’m also going to be checking out the article you referenced. I don’t use olive oil for much other than salad dressings, but I still hope mine turns out fine!
Linda in Oregon
Grocery Outlet, Seville, cold pressed, extra virgin olive oil, imported from Italy, dark green bottle. Seems like it says all the right things, but it’s as liquid as it was when I put it in the refrigerator for 24 hours. Grrrr…
Fred Meyer, Filippo Berio Olive Oil, since 1867!! for sauteing & grillings, made from select high quality olive oils from Italy, Spain, Greece and Tunisia same story, totally liquid.
Thanks so much for this information Tiffany. I’m disappointed in my oils. I saw one from Calif. at Grocery Outlet, I think I’ll try that one next. Hopefully they have higher standards in place. I just figured if the olive oil was from Italy, it had to be good. Guess not. 😉
Tiffany
Linda in OR,
I appreciate you sharing your experiences, even though they didn’t turn out as expected 🙁 Unfortunately, more proof that all those fancy labels are just for sales. Thanks again Linda, and please do keep us updated!! ~Tiffany
Lisa Lynn
Thank you so much for sharing this on The Creative HomeAcre Hop! I hope to see you again tomorrow. 🙂
Kimberlee Tangen
This was very informative; however, I would like to know why you are no longer cooking with olive oil?
Tiffany
Hi Kimberlee,
Extra Virgin Olive oil has a smoke point of 350 degrees, which is relatively low for what most people use liquid oils for including sauteeing. The smoke point is when the oil can become damaged and create free radicals, toxins for your body. Since we don’t really know what temperature low/medium/high is on our stove tops, it’s best practice to just use a better fat for cooking and save olive oil for straight up eating. Here’s more information on smoke points that may help: https://dontwastethecrumbs.com/2013/02/truth-about-fats-smoke-points-cooking-temperatures-and-choosing-the-best-fat-for-dinner/ Thanks for your kind words! ~Tiffany
Jill's Home Remedies
This is so great to know! Thanks for sharing, and I’ll be giving this a try!
Lindsay
Just wanted to chime in with Valerie that I too tested my Bertolli EVOO and it didn’t solidify… so it’s unlikely that BOTH of our fridges weren’t cold enough. I also had used half of my bottle and can’t return it. I just found a list this week with “impure” honey…
http://worldtruth.tv/75-percent-of-all-honey-sold-in-stores-contains-no-honey-at-all/?fb_action_ids=10151517165419589&fb_action_types=og.likes&fb_source=other_multiline&action_object_map={%2210151517165419589%22%3A10150456215844398}&action_type_map={%2210151517165419589%22%3A%22og.likes%22}&action_ref_map=[]
if anyone is interested it might save someone some money on impure honey!!
Thanks Tiffany for all the time and research you put into keeping us informed!
Tiffany
GREAT information – thanks for sharing Lindsay! I do feel a little better about Kirkland honey now, but still even more tempted to buy it from the farmers market instead. Sorry to hear about your Bertolli too. 🙁 ~Tiffany
Denice
I know you don’t want to cook with olive oil, but a nutritionist told me years ago that you should only cook with REGULAR olive oil ONLY. She said Extra Virgin Olive oil has a “low smoke point” and is carcinogenic when heated enough to actually cook something.
Orlando Cruz
Absolutely correct!
Blair Massey
This was a very interesting test. Consumer Reports did a test on olive oil last year. Costco’s Organic Extra Virgin Olive Oil came out on top for purity, taste, price and having the correct darkness to the container. This is the only brand I buy unless I can get Olive Oil from a small local farm here in California. It is important to know that you are getting what you pay for. I do the same thing with honey. Practically all honey is adulterated with high fructose corn syrup. YUCK!
bob
The bulk olive oil from New Seasons, (for those of you in the NW) tested out fine.
Susan
Recently read that taste is the only true way to tell undiluted virgin olive oil, but how many of us know what the “taste” should be like.
Gina
I buy the same brand of olive oil from Costco that you do. But I’m thinking since it did solidify that’s a good thing. Now that we have a Trader Joe’s somewhat nearby (45 minutes)I think I might go with that brand next time. Great info-thanks!
Valerie B
Wow, I feel like I’ve been completely screwed over! I tested Bertolli EVOO and DaVinci 100% Pure Olive Oil and neither one solidified. The DaVinci, which I didn’t expect to, actually got a little thicker, while the Bertolli is still just as liquid as when I put it in the fridge (well over 24 hours). I’ve used at least half of both bottles so I don’t think I can return them, but you can bet I’ll be trying a different brand. Or just not using it very often and realizing that it’s not pure olive oil. I will be writing to the company though. What’s next – artificial sweetener in my milk? Oh wait…that’s coming too. Grrrrr!
Tiffany
Valerie,
What a bummer! 🙁 However not using it as often, knowing it’s not pure, is an excellent way to not waste resources (given that you can’t return them). Thank you for posting the brands – it allows the rest of us to make educated decisions too. And please let us know when you find a good one too!!
Artificial sweeteners in our milk… I know it. Much more to say on that topic than this tiny comment area will allow. 😉 ~Tiffany
Mary Katherine
Valerie, if the DaVinci brand got thicker (and the other brand not at all) – maybe there is a chance your fridge wasn’t cold enough.
Did you try making it colder, and trying again?
Tiffany, what setting did you use?
Tiffany
Mary Katherine,
My fridge was as cold as it could be. The beef on the top shelf nearly froze!
bob
WHOLE FOOD is the only way to go and raw milk is on that list. If you get anything else well…good luck. They have found uranium in milk and cheese…so like I said good luck.
Shannon
Bob where are you finding raw milk? I would buy it but unpasteurized dairy is banned in Canada and the US…except for Quebec, and I’m not going there to get it 😉
vicky
You can buy raw milk in Canada by buying a share in a cow. I live in Calgary and my raw milk was coming from Vancouver. About $7 a litre. I bought some for about a year but then the pick up and drop offs were becoming too much when the truck was late or broken down and I was tied up so I quit. But it was very tasty.
Tiffany
Thanks Vicky for chiming in on raw milk on Canada! I greatly appreciate it! 🙂
Lorien
you can purchase raw milk in many places in the states. Some require off the farm purchase only and some allow it to be sold in stores. I used to get it straight from the store in NH. There are states that do not allow raw dairy in any form even cheese. Colorado where I now live is one of them. You would have to find a farmer willing to sell it to you illegally off the farm but they are out there if you live in a state that gives itself the right to tell you that you can’t eat what you want.
Stephanie
raw milk is not banned in the US. That is a misinterpretation of the law. Each state has its own regulations. I live in Pennsylvania where you may buy raw milk as long as the FDA has certified is safety. They check the raw milk approved Farms 3 times per week. That is why it cost a fortune you’re paying for the FDA inspector
Susan
News update. West Virginia is now allowing sales of raw milk. Would love to find a dairy or farmer to buy from with confidence.
Jeannie
Unpasteurized is not banned in Texas. You can buy directly from dairy farms. Its delicious.
Brian
I don’t think you should post here anymore
Tiffany
No worries Brian – this is a pretty old comment and I don’t think she meant any harm. 🙂
Anna
Which olive oil did you buy from Costco? The one I have is their organic olive oil, I will have to perform the test and let you know how it goes :)!
Tiffany
Anna,
I do NOT have the organic variety – just plain “Kirkland Extra Virgin Olive Oil.” Do test, and let us know! Thanks!! ~Tiffany
Teri
I have a question – How would you go about testing the olive oil before you buy it? I would be very upset to purchase a bottle of olive oil, then do the test at home, only to find it has been watered down. I haven’t test the bottle I have now, in a way I am worried it may be diluted. Is there a way to test in the store?
Tiffany
Teri,
I don’t know if you can test olive oil before you purchase it, unless you purchase it specifically from an olive oil shop, but even then it would require refrigeration and I don’t know if that’s something they will accommodate. The only way you could test in a store is if you put the oil in a chilled location (like where the milk and eggs are) and came back the next day… but I don’t know how plausible that is.
Going forward if I try a new oil, I plan to test it when I get home and return it if it isn’t pure. Most stores have return policies that should allow this.
The bright side is once you find one or two oils you trust, you shouldn’t have to re-test them unless you have reasons to suspect they’ve been tampered with. ~Tiffany
bob
There is such a thing as customer service. You buy the oil, take it home, put the whole jar in the fridge. If it solidifies then you know, if it doesn’t return it. Really it is THAT simple. Tell the folds at the store if it is NOT olive oil and maybe they can put pressure on their buyers to get the real deal.
Russ
Hi Tiffany,
Great article. I also read the article about whether or not the refrigeration test is valid. I just tested some olive oil from Trader Joe’s; Premium, Extra Virgin, All Natural, Cold Pressed, Imported from Italy. I poured some in a saucer and some in a juice glass and left them in the refrigerator over night. They’re still liquid. No solidification yet, not even a sign of solidifying.
I’ll leave them for a full 24 or even 48 hours and see if it just takes a little longer.
Tiffany
Thanks for the compliment Russ, and for sharing your test results!!
Joe Cannizzaro
I’ve read many ways to test olive oil and sadly most of them are not fool proof because the oil can be mixed with other kinds of oil such a corn oil or canola etc. Fortunately, I received olive oil that my uncle in Italy had pressed by a local guy with my uncle’s own produce. I applied a trick to tell if the olive oil was pure an old friend once told me. The trick is to apply a very small amount (less than a penny in size) and rub your hands with it, your hands should not feel greasy at all. In fact, you shouldn’t even want to wash your hands for how soft they are. Compare it with other kinds of olive oil or even worse, canola. Your hands will feel so greasy that you want to wash them. The problem is that olive oil is not 100% olive oil but mixed, most of the time unless you pay 15-20$ (CAD) a litre. Anything less, you’re buying diluted olive oil with other. Smoke test won’t work, fridge test neither, smell taste neither. Maybe the tingle that occurs with real olive oil will be present like was with the olive oil produced by my uncle in Italy. You must compare with an olive oil of quality before testing the others. Joe Cannizzaro
Bonnie
I am grossly allergic to soy. When I eat a small amount it blurs my vision for hours., but I can generally talk and move around without severe problems.
I’ve never had the courage to test my reaction to measured amounts of soy. All I know is that if I ingest too much soy, my hands and face turn numb and I cannot see, talk, stand or walk. I’ve never found a doctor interested in helping me identify anything helpful relating to my soy allergy.
Fred
You do have to retest them. I just bought a bottle of Lucini olive oil and it didn’t turn white or change at all in the freezer. It used to be real, but apparently it ain’t anymore.
Bob
Sams club members mark olive oil will not solidify . Back it goes
Richard
If you read the article carefully you can easily figure out that the author is a quake and the test almost useless.
The only valid results possible from the test after 24 hours in the refrigerator is that it remains liquid and is therefore likely not olive oil.
Most, if not all, monounsaturated oils solidify in the refrigerator. That means the solid in your refrigerator could be peanut, coconut or many other oils and not what you paid for. Another thing that should have been mentioned in the article is that a recent study indicated almost 70% of the labeled EVOO in the US is fake.
Tiffany
Hey there Richard – you might not have seen this, but this article was originally shared in April of 2013… so if your “recent study” truly is recent, it would not have been available at the time of publishing. There is however a link in the article (the very first link) that highlights a news story that does cite the tampering of olive oil. If you would be so kind as to leave a link to the study you’re referring to, I’d be happy to read it.
Also, to address the validity of the test, there is an update towards the bottom, where the discussion of whether this test is valid or not continues. I encourage you to click it and continue reading.
Lastly, this is a positive and upbeat community. Name calling will not be tolerated, and honestly, isn’t necessary. If your comments do not further the discussion in a helpful manner, they will be deleted. 🙂
kim
UC Davis did tests in 2013 of this refrigerator method and also tested chemically that the olive oil was ‘pure’ and the opposite was true, was there another study this was based on? They found that the lower grade oils solidified and not pure EVOO so I’d love to see the contrary data source to see what factors they were looking at
Martha
What the hell is a quake . do you mean quack so your calling her a duck or a goose. See the problem here is Dickard is that your bored and boring . to be. Been eating too many iron filings from to much cornflakes.lol
Just Curious
Richard, I believe the derogatory term you are looking for is “quack” not “quake”. If Tiffany was a quake that would really be something to talk about. Quacks on the other hand are a dime a dozen.
To round up, if still liquid, not olive oil, if solid, it just might be olive oil.
Has anyone ever seen verified EVOO that remained liquid after refrigeration?
Linda
Research