Saturday, January 23, 2010

Yarrow craft group: Bath bombs & bath salts

Click here for the handout from today's class!
These are super easy if you follow the instructions properly. Bath bombs are made with citric acid and baking soda. When you add them to the bath, they fizz up when they touch the water. (It's like the volcanoes we made for school as kids with vinegar and baking soda. Only in this case, the vinegar has been replaced with citric acid. When it touches the water, it starts an acid-base reaction, causing the fizz!)

Ideally, you won't use any water based ingredients in bath bombs. Stick with fragrance oils and powdered or oil based colours. Having said this, we did use water soluble colours in our class today. If you put the drops of colour into the little puddle of fragrance oil or soybean oil, you won't set off the fizz. Only use a titch or two of colour - one or two drops for the recipe below - and you won't get fizz!

Finally, bath bombs are humidity sensitive. The citric acid is a humectant - it draws water from the atmosphere to it - so the higher the humidity, the higher the possibility you will get "warty" bombs that react to the moisture. I solve this problem by making bath cupcakes - the liner for the cupcake and the icing on top hides the warts!

My recipe:
1 cup baking soda
1/2 cup citric acid
1 to 2 tbsp oil of your choice (I like soy bean oil, but olive oil is awesome also)
3 to 5 ml (3/5 to 1 tsp fragrance oil)

Mix together your baking soda and citric acid. Then add the oil, a few drops of colour, and your fragrance oil. Mix together well. Press into a mold - a silicone ice cube tray or a silicone cupcake tray lined with cute decorated liners - and let set. You can try them about 20 to 30 minutes later. If you go to press it out and it doesn't pop out, it's not done! I tend to let my bath cupcakes sit overnight if I have the time.

Note: This is a 2:1 ratio of baking soda to citric acid. The recipe we did today - the one in the handout - is a 3:1 ratio of baking soda to citric acid. I wouldn't go with 1:1 or 4:1, but the other ratios work well. Why would you use the lower ratio - so you can make more with a craft group!

Click here for today's handout on bath salts.

These are even easier than bath bombs! You can use water based colourants and fragrances for this project.

My bath salt recipe - should do two baths!
1/2 cup epsom salts
colour (use food colouring here if you like)
2 to 3 ml fragrance oil of your choice
Put the epsom salts into a cup. Add your colour. Add your scent. Stir. Package in a cellophane bag or glass container. Label and give to your favourite person who needs a hot, relaxing bath!

Note: Do not package these in plastic sandwich bags. The plastic in those bags will suck out the scent. Store in a glass container or cellophane bag to retain the smell.

Please join me May 1st for another parent-child class - we're making melt & pour soap!


andreja said...

Thanks for your bath bomb recipe! I've tried it before and it works every single time. I've tried other recipes with call for water and every time my bombs, I got warty bombs. With your recipe, there is no hassle at all. I do add more oil though. I keep adding oil until the mixture sticks together when I press it with my fingers.
I did use water based color the last time I've made bath bombs and I did get some fizz, but I quickly added some corn starch and I was able to stop fizzing and at the end, bombs didn't end up being warty at all.
Again, thanks for the recipe, my kids are very grateful. So am I, I just need more free time to actually use bath bombs myself. lol

Tara said...

I find using cocoa butter for the oil results in nice hard bombs.