Oh soap making is great fun
BUT you are working with caustic soda, so you need to take serious safety precautions
Safety googles, rubber gloves and an apron as a minimum and a big bottle of white vinegar on stand by in case of any splashes (I've given myself some sore ones
)
For your peppermint I'd try infusing some with warm oil to get the scent (or you could add it into your lye solution, but it might discolour the leaves) or you could chop it up and mix it through the soap just before you pour it into moulds.
I made some with peppermint essential oil once - it went a funny kinda green/orange colour - smelt great but looked bizarre
Here's some previously written instructions I sent to a friend
Before you start gather all your ingredients, you'll also need a pan for melting the fat and 1, if not 2 heatproof jugs, 2 thermometers (I got jam ones from ebay for 99p each - they're great !) You'll need a whisk or a stick blender to mix it, rubber gloves, safety spex and a facemark isn't a bad idea to save you inhaling any fumes.
So first I mix my lye solution - measure out the caustic soda (everything in soap making goes on weight - not volume) and add it slowly to the distilled or mineral water, stirring all the time - DO NOT stop mixing til it's all dissolved. Keep your nose away from it and try not to let it splash on you (white vinegar is the best thing to neutralise any spills - keep a bottle close by) Once it's mixed pop a thermometer in it and watch - it'll go up to around 200F, that's fine just set it aside safely and let it cool down. Keep kids and pets well away from it !!!
While it's cooling melt your fats in a big pot, then add any liquid ones. Remember to weigh the oils/fats - even liquid ones, it all goes on weight. Pop a thermometer in and see what it's reading.
For this recipe you're aiming to have both lots of liquid at a temperature of between 110F and 115F before combining them - different recipes call for different temps. Sometimes you need to put the pots/jugs into iced water/hot water to adjust the temperatures, it can be a bit of jiggery pokery to get them the same, at the same time - but they have to be for it to work properly.
I tend to have all my oils in a plastic bucket (old mayo bucket) but as long as you're using something 'non reactive' (ie. not aluminium or cast iron) and big enough to cope with both lots of liquid it's fine.
When the oils and lye solution are at temperature, slowly start to mix the lye into the oils, ALWAYS add the lye to the oils and not the other way round. This is when you have to start mixing, either with a hand whisk (which could take an hour or more - I did it this way the first time !) or using a stick blender. But only use a stick blender that you're not going to use for food !
Now you want to mix til you reach 'trace' this is when the soap sits on the surface for a second before dissapearing back in, or your whisk leaves a trail on the surface. The consistancy thickens as cream does, and it can happen pretty quick with a blender - 5 minutes, so be careful it doesn't go to firm or you'll have bother pouring it
If you want to add colour or fragrence now is the time to do it - once you've got any colour or scent blended in (I always do this with a hand whisk) you can pour it into the mould.
You can use silicone trays, loaf pans, even old pringle tubes or juice cartons - or you can buy soap loaf moulds. The choice is endless !
Once in the mould cover it and insulate it well. You can either wrap it in old towels, or I have a polystyrene box kept specially for this purpose, it works a treat !
Leave it completely alone - don't even look at it, for 18-36 hours. After this time it should have cured enough that you can turn it out the mould and slice it. If it sticks you can pop it in the freezer for 30 mins to help turn it out.
After it's sliced it needs to cure further for anything between 3 and 8 weeks, this recipe when I did it, was fine after 3 weeks.
The longer it cures before use the harder it becomes and the longer it lasts. You can still use it before it's cured, but it just won't last as long.
And that's about it ! Apart from the recipe (ooops nearly forgot that !)
64oz lard
20oz olive oil
4oz castor oil
12oz lye crystals (sodium hydroxide)
32oz distilled, spring or mineral water
Combine oils and lye at 110-115F.
This
is quite a big batch of soap - and you might not want to use lard, just be sure to run the amounts through a lye calculator to make sure you're using the right amount for the amount and type of oils you use - the one on Brambleberry.com is good (and easy to use
)
HTH
Karen