Shelf life of oils and soap

[MicheleH]

Will the expiry date on the oils I use affect the shelf life of the soap?

I have purchased some coconut oil and it has quite a short expiry date. Will it matter as long as I make the soap prior to their expiration? Or will it be prone to DOS??

 

[user 49910]

Coconut Oil shelf life is approximately 24 months if you're using refined Coconut Oil, coconut oil doesn't go bad after the date on the label. It's okay to use for months or even years after that date if stored properly.

Coconut oil takes a long time to oxidize which means it takes a long time to go bad. As mentioned above, refined coconut oil can last up to 24 months while virgin coconut oil can last up to five years. Any oil stored carelessly can go bad faster than expected.

Usually it is the soft oils such as olive oil that may cause the dreaded orange spots if they've gotten old. Oils low in linoleic and linolenic fatty acids have longer shelf lives.

Also adding a 0.1% amount to oils percentage of Rosemary Oleoresin Extract or ROE, will help extend the shelf life of the soap.

I have personally used coconut oil that was over 4 years old and it had no odor and behaved the same as fresh off the shelf coconut oil.

 

[lsg]

I have had no problem with my coconut oil going bad.

 

[Garden Gives Me Joy]

[...]
Also adding a 0.1% amount to oils percentage of Rosemary Oleoresin Extract or ROE, will help extend the shelf life of the soap.
[...]

After adding the ROE at 0.1% ppo, how do you state your shelf life to others? If you seal your soap, how much time after 'breaking' the seal can someone use it? .... and or, if you do not seal the soap, how much time do you state overall? Is there a standard or general expectation for natural soap?

I am thinking about adding my antioxidant as soon as possible after buying my oils ... ie versus waiting until later when I eventually make soap. However, I wondered whether there is any potential danger if this practice translates into an overall increase of antioxidant in the final product to a percentage beyond 0.1% ppo. To explain the type of scenario I mean; let's say I added the antioxidant to only olive oil (OO) but at the rate suitable to be 0.1% for the entire recipe in which I use it but then later change the recipe a little, thereby essentially altering the overall usage rate of antioxidant beyond 0.1%. ...or, if it will actually be useful, should I endure the tedium of adding the antioxidant to all of my different liquid oils at 0.1%?

[ETA] PS. Happy for direct link to instructions for dealing with multiple dates like breaking seals and overall.

 

[DeeAnna]

There is no legal requirement to provide a "best by" date or expiration date for soap. This is soap, not an edible foodstuff.

Sealed packaging is used for products where exposure to air introduces the chance of microorganisms and provides exposure to open air. Soap is never stored in airtight/hermetic packaging, so I fail to see the concern about "breaking the seal".

It's best to add an antioxidant to fats upon receipt so you reduce the rate of oxidation in the fats from the very beginning. Don't wait to add antioxidant to soap -- this practice is the equivalent of storing cookies in the open air, putting them in a container a week later, and then being upset because the cookies are dry and hard.

Antioxidant should be added to fat at the required rate for the actual weight of the fat, no more. Do not add antioxidant at a higher rate than recommended. Overdosing can increase the rate of oxidation, not slow it down. If you feel the need to add antioxidant later when you make soap, then add another appropriate dose at that time. Don't overdose then either.

 

[DeeAnna]

To answer the OPs question -- The expiration or "best by" date on foods is only a rough guideline, not a requirement.

I use food with the shortest expiration date first so I can keep the food in my pantry as fresh as possible. Even if the expiration or "best by" date is in the past, the food is still safe to eat.

For soap making fats, the same is true. Use your nose and common sense to determine whether the fat is rancid or not, not the expiration date.

Even if you use fresh fats to make your soap, that does not guarantee your soap will not become rancid faster than you would like. Storage conditions, impurities, and many other issues can accelerate the rate of oxidation and the appearance of rancidity.

For the longest shelf life, I recommend using an antioxidant such as ROE (rosemary oleoresin extract) and a chelator such as tetrasodium EDTA or sodium gluconate or sodium citrate.

 

[TheGecko]

Will the expiry date on the oils I use affect the shelf life of the soap?

I have purchased some coconut oil and it has quite a short expiry date. Will it matter as long as I make the soap prior to their expiration? Or will it be prone to DOS??

The majority of 'best buy/expiration' date is an advertising to get you to use up and buying more product. As an example I bought a 35 lb bucket of Palm Oil..."shelf life" is approximately one year; I bought it in March 2020 and I'm still using it with zero problems. Of course, after I bought it I melted it all down, gave it a really good stir to distribute the stearic acid, let it cool down, stirred it again and then filled one-gallon zip-lock bags two-thirds full, removed the air out of the bags, put the bags back in the bucket, closed the lid and put it in the coolest/darkest place in my garage.

I also Master Batch my Oils/Butters and Lye Solution which means I am not opening containers every time I make soap. Two of the reasons why I got into Master Batching because of my concerns about the affect on my having to remelt my Palm Oil all the time was having on it. And because I wanted to start buying larger quantities of ingredients and worried about constantly exposing them to the "air". And even with Master Batching, because I wasn't making as much soap as I had planned to this past year, I did follow @DeeAnna's suggestion and added ROE to my MB'd Oils/Butters.

 

[Garden Gives Me Joy]

[...]
Antioxidant should be added to fat at the required rate for the actual weight of the fat, no more. Do not add antioxidant at a higher rate than recommended. Overdosing can increase the rate of oxidation, not slow it down. If you feel the need to add antioxidant later when you make soap, then add another appropriate dose at that time. Don't overdose then either.

Thanks a lot. This concept was new to me. I was literally about to get heavy handed with antioxidants.

Would I be correct in assuming that, since over-dosing with antioxidants are risky, the only further anti-rancidity supplementation should be sodium citrate and or sodium gluconate because they are not an antioxidant but chelators?

 

[DeeAnna]

...since over-dosing with antioxidants are risky, the only further anti-rancidity supplementation should be ... chelators?

If you have already added an appropriate amount of antioxidant and wanted to go a step further, then I agree you'd want to consider adding a chelator.

 

[TashaBird]

If you have already added an appropriate amount of antioxidant and wanted to go a step further, then I agree you'd want to consider adding a chelator.

is it too late to add ROE to fats half way through a container? Also, is citric acid the same as sodium citrate?

 

[DeeAnna]

You can always add ROE to oils. By adding it up front, your oils get the most protection for the longest time. But it's worthwhile to add ROE whenever you can. Better late than never!

Citric acid isn't the same chemical as sodium citrate. You can make sodium citrate by reacting citric acid with sodium hydroxide. Because we use sodium hydroxide to make soap, some soap makers add citric acid to their lye solution with the extra sodium hydroxide that citric acid needs to turn itself into sodium citrate.

Other soap makers buy ready-made sodium citrate and use that instead. Using sodium citrate rather than citric acid eliminates the need to add the extra sodium hydroxide and deal with that extra math.

But in the end, however you get there, it's citrate that is the chelator in soap, not citric acid.