Foodstuffs in soap

[KiwiMoose]

Hi - sorry for all the questions, but I'm very keen to learn.

If I put fresh squeezed lemon juice, or grated lemon rind, grated fresh ginger, or herbs and spices (fresh and/or dried) into my soap - what effect will it have? And does it affect the longevity of the soap - as in, will the food item go off or mouldy as the soap cures?

What items have you used, and with what success?

 

[steffamarie]

Any chunks are prone to spoilage. Purées are ok provided they are very fine. Lemon, being acidic, may neutralize a portion of your lye. I’m not sure how much, best to check with someone like DeeAnna. Dried herbs and dried lemon peel may be scratchy or cut your skin. I’ve used oat flour with success, as well as walnut shell powder, coconut milk and coconut milk powder, buttermilk powder, honey, and tea-infused oil. I’m too wary of spoilage to try much in the way of purées but many people do here.

 

[lsg]

Lemon juice can affect the way the lye works in your soap. Depending on how much lemon juice you use, you could have a failed batch.

 

[ibct1969]

I think that adding things like purees, herbs etc only add to the aesthetic value- they don't make a difference in the soap for the most part. Purees can work well but I'd google that or search this forum for how to successfully use them. I have seen beautiful soaps made with ground herbs, but they were ground very fine (otherwise they'd be scratchy). If you add them to the top of the soap, they can turn brown if you add them too soon - before the batter is thicker (this happened to me when I added rose petals to one of my soaps). Calendula is pretty and doesn't turn brown- I have infused this in olive oil and sprinkled some on top of a batch I made.

 

[dibbles]

Any botanicals such as herbs or flower petals need to be dried. And most will turn brown. I have used carrot, avocado and cucumber puree in soap with no problems. I have tried cinnamon, paprika and coffee and found them all to be too scratchy for my taste for use as a body bar. But in the case of the cinnamon and paprika I wanted speckles and wasn't looking for exfoliation. I have used ground poppy seeds, but in this case I wanted mild exfoliation. I have infused annatto seed in olive oil for color which works well. I have some black walnut shell powder I received as a sample which adds specks without being scratchy. Cocoa powder and carrot powder were fine as well. Salt bars are lovely - use fine salt (not Dead Salt).

 

[DeeAnna]

Info about adding acids to your soap -- https://classicbells.com/soap/soapystuff.html and scroll down to "Acids and Salts"

 

[earlene]

Many of us have used a variety of different liquids to replace some or all of the water in our lye solution. Lemon juice can be used and I have done so myself, without any difficulty. But if too much is used without accounting for the effect on the lye, then it can mess up the soap. Same with vinegar.

Some other liquids have sugars that when mixed with lye can cause it to boil up and spill out the top of your lye solution container, so that's something to research before trying it with any liquid that contains sugar. Alcohol does the same, so requires caution!

Botanicals of many types have been used in soap, but as mentioned already, dry powdered is preferable to wet if you are going to try herbs or flowers. Oil infusions with botanicals can produce nice colors sometimes. Some botanicals create nice colors when mixed with the lye solution. Research on these different methods and particular botanicals will help you decide which ones you want to try.

Solid food is definitely not good in soap. A very fine puree is required and you need to hold out an equivalent amount of water from your recipe to replace with the puree, otherwise you end up with too much liquid and the soap may not firm up ever. Some pureed foods turn brown in soap and don't look very attractive. Some hold up the color, some fade over time and lose their color. When you want to use a particular food item, post a specific question, and someone here has probably used it and can give you feedback.

 

[Sk8rTips]

As the others have said, I'd stay away from bulkier / more sizeable food products like peel etc as they're *super* scratchy on the skin. And not in a nice, exfoliating kind of way. I learned that the hard way...

 

[KiwiMoose]

Info about adding acids to your soap -- https://classicbells.com/soap/soapystuff.html and scroll down to "Acids and Salts"

Thanks for this resource DeeAnna. I just want to check if I've done my maths right:

I plan to add 100g of fresh squeezed lemon juice to my soap. This will yield 5g of citric acid, which will neutralise 3.12g of my lye. Your webpage suggests that I should have no more than 2% citric acid to oil ratio, so if I'm using 500g oils I'm at only 1% with my 5g, so should be ok. Is the maths OK so far?

Next question: Do I need to reduce my water content by 100g ( to account for the extra liquid in the juice) AND add an additional 3.12g of lye (to account for the amount that will be neutralised by the citric acid content)

Next question: Should I add the juice to the oils before I mix with the lye water, or should I emulsify a bit first and then add?

I plan to add an EO or two also in case you were wondering.

Last question ( from any soaperts out there): Do you reckon this will even work?????

 

[DeeAnna]

Your answers sound right to me.

The lemon juice will be part of the "water" for your recipe, so your thinking about that is correct -- subtract the juice weight from your total water weight. The answer is the amount of additional "real" water you will need. I know there are small amounts of things other than water in citrus juice -- obviously the citric acid -- but for the sake of simplicity, I assume the juice is all water. This assumption is good enough in this situation.

You can add the juice to the fats or to the lye solution. Pick the method that seems best to you. I hope others will chime in with their preferences.

The "add the juice to the lye" method can be done in a couple of ways. One is to mix the juice with your water and make the lye solution using that mixture. Or make the lye solution with plain water, and then add the juice (slowly) to that lye solution. This lets any chemical reaction happen in the lye solution before you start to soap. When people use vinegar in soap, they often use the vinegar as a full water replacement, so they have to make the lye solution with the vinegar -- there's no extra plain water to make the lye. If you wanted to use citrus juice as a full water replacement, you'd have to do the same thing.

The "add the juice to the fats" method is usually done something like this -- add the juice to the fats, stick blend a second or three to make a temporary emulsion, and promptly add the lye solution. The fats essentially dilute the juice and the lye. This helps to slow any chemical reaction and reduce any temperature increase from the chemical reaction.