Sunday, 28 July 2013

Soap Making - Rendering the Fat

Making the lye, step II is going to be some time happening on this blog. I tried to filter my batch and again, no lye. The egg sank and when I tried using a hydrometer to test the specific density, the density was the same as water. To add salt to the wound, there appeared to be maggots living in my supposedly caustic solution quite happily, so lye it very much wasn't. I chucked it out and I think I've identified where I went wrong on this attempt, and it's one of three options:
  • I misidentified the wood and you simply can't leach lye that isn't there. 
  • I had too little ash to too much water, so it would have been lye, if I'd evaporated off some of the water,
  • or I had lye, but didn't filter it soon enough, so it exhausted itself on the straw in the bucket 
In the mean time, I've been working on the oils I'll be using for this project. Thanks to a local butcher, I've gotten my hands on pig and cow fat which I'm wet rendering down into a usable fat for soap making. Wet rendering involves adding the fat to hot water and summering away, periodically skimming the fat from the surface of the water. This method gives a lighter, more deordorised form of fat, and leaves my kitchen smelling faintly of bacon. The resulting lard is beautifully silky, and as previous soap making I've done has exclusively been vegetarian in ingredients, and I'm really looking forward to seeing how well it turns out as a soap. 

The beef gave up it's fat more readily, giving a harder, lightly yellow coloured fat. It's easy to see how this gives a harder soap. 

Now I just need to get my hands on the commercial potassium hydroxide pellets a friend secured for me, and I'll be able to start soap making! I have a total of 8 bars planned: pure lard, pure tallow, tallow & lard comabined and olive oil - each of these combinations I'll do once with potassium hydroxide (KOH) and once with the more modern sodium hydroxide (NaOH) for comparison. 

I'm also tempted to put some of the lard to use in enfleurage - a technique for, well, harvesting the perfume for delicate blooms while the Whiskey Mac rose is still blooming in the back garden. And if that's successful, it'll make a most delightful soap.

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