Comments on: Salad Dressing: The Silent Killer

By: Dr. Cate

Dr. Cate — Wed, 01 Feb 2012 04:03:58 +0000

HI Mikki
If you and are talking about making a fresh batch of oil with garlic, there is no risk of botulism whatsoever. Bacteria that produce botulism toxin are not pathogenic to humans, it is ONLY the toxin that they produce that harms us. This toxin can be produced in appreciable amounts under anaerobic (no oxygen) conditions that are not met in either a clove of garlic or inside our intestines.

HOWEVER, if you are talking about making dressing by doing a garlic infusion in oil where the garlic sits there for a while, then that’s an entirely different matter.

Yes there can be growth of enough botulism bacteria to create gas (that should be visible as bubbles or detectible as a fizz with opening the bottle) and a dangerous dose of botulism toxin.

As to the effect of acid: While the acid in the vinegar would prevent the growth of botulism bacteria in a garlic vinegar infusion, the vinegar would not be miscible with the olive oil and therefore would not lower the Ph of the oil enough to prevent the bacteria’s growth.

Bottom line:
Garlic vinegar infusion: low pH, not anaerobic, likely very safe
Garlic oil infusion: higher pH, potentially anaerobic, likely very unsafe

By: Mikki Coburn

Mikki Coburn — Tue, 31 Jan 2012 21:59:05 +0000

Hi Dr. Cate! I just shared this post about salad dressings with my local WAPF chapter and this question came up which you being a doctor would know. I certainly don’t! Is there any danger to getting botulism from raw garlic with the root end attached if there happens to be some soil contaminated with it? A person asked me this and was worried when he heard about a jar of garlic oil exploding when opened. He wanted to know if adding vinegar kills bacteria, which I know it does if enough is used, but I think he’s asking about making dressing with it and I do see you use only garlic powder not fresh and this might have prompted his question. Thanks if you can help me out. Mikki

By: Dr. Cate

Dr. Cate — Tue, 29 Nov 2011 04:45:06 +0000

Patsy

Jeanne was hit by a 5 day power outage right after I asked her for her recipe. She’s rebounded and has kindly supplied the secret formula for perfect buttermilk dill dressing to us, which I added to the post above. Thanks, Jeanne!

By: Patsy

Patsy — Mon, 07 Nov 2011 17:07:43 +0000

May I have that recipe? “Buttermilk Dill Dressing” by Jeanne. Sounds yummo.

By: Dr. Cate

Dr. Cate — Thu, 06 Oct 2011 12:07:08 +0000

Very helpful points about sugar and salt, thank you, Jeanne!
Your buttermilk dill dressing was divine, by the way.

By: Jeanne Martin

Jeanne Martin — Thu, 06 Oct 2011 02:09:49 +0000

I realize that people have different tastes, but I would seriously reconsider the ratio of oil to vinegar/acid in these recipes. They are way too acidic in my opinion with a ratio of approximately 2:1. I have tried even the traditional ratio of 3:1 that rouxbe and other traditional sources recommend. My family will not eat dressing with this much acid without a good deal of sugar to balance. I use a ratio of between 5:1 and 8:1. This means that for ½ cup of oil, the amount of acidic ingredients should be between 1 and 1 1/2 TB. The other thing these recipes lack is salt. Every ½ cup of oil should be seasoned with at least 1/2 tsp. salt. I would also boost the amounts of the other flavors.

I think a very important issue to consider is balance. Most people are used to a balance of sweet/sour in dressings since most commercial dressings contain sugar of some sort. (sweet/sour balance – think lemonade). If you choose not to use sweetener, then for many people, the amount of acidic ingredients in a dressing with a 2:1 or a 3:1 oil/acid ratio will be too sour. If you find these recipes too sour, try using less vinegar/acid and boosting the amount of salt and other flavorings. Homemade dressing can be delicious! It’s just a matter of finding the ratios that work for you.

By: Dr. Cate

Dr. Cate — Tue, 27 Sep 2011 23:17:49 +0000

Hi Pam
I totally forgot about that old thread! Our conversation ended by Eddie, who deserves credit for this, sending me a photo of a giant plastic bottle of canola where right on the label it says 1.8% trans fat. Which settled the issue for both of us. Not everyone would go out of there way to prove themselves corrected, thanks again Eddie, if you’re still out there.

According to the textbooks, is impossible to find canola with less trans fat than that, so most canola oil probably has more. I reference a study in Deep Nutrition that said up to 5% off the shelf, and because MegaTrans can oxidize and multiply, another study that says when you cook with the stuff you can generate as much as 27% trans fat.

By: Pam

Pam — Tue, 27 Sep 2011 16:25:59 +0000

Hi Dr. Cate –

I see that you were relocating in 2010 and mentioned you weren’t able to respond promptly to all comments. I am curious about your thoughts to Eddie’s second post above. I am not a scientist and so my head hurts reading through it. I am trying to convince my in-laws not to use canola oil and so I am hoping to get all of my ducks in a row.

thanks! Pam

PS I was able to get our library system in Massachusetts to order both Deep Nutrition and Food Rules!!!!

By: Cherry Clavette-Arnold

Cherry Clavette-Arnold — Mon, 26 Sep 2011 00:54:57 +0000

I made a great vinaigrette with yogurt today. Here is the recipe:
1 cup of good olive oil
1/3 cup of balsamic vinegar
2 TBSP dijon mustard
2 TBSP full fat yogurt
1 TBSP finely minced onion
1/2 tsp sea salt
2 tsp oregano

Place all in a shaker bottle, shake & enjoy! I had mine on a greek salad

By: Quickie Salad « Between Two Truths

Quickie Salad « Between Two Truths — Wed, 01 Sep 2010 08:16:11 +0000

[...] will you please kill the salad dressing. All you need is a little olive oil to bring out the flavor of the veggies and/or a spritz of lemon [...]