Soap rebatching: because sometimes s#!t happens. Why rebatch soap? Well, for any number of reasons.
- Maybe it cooled too quickly the first round and still needs a couple more hours.
- Maybe it finished with some still-active lye. (Like when making coffee soap.)
- Maybe you want to add certain delicate essential oils that have a difficult time surviving regular saponification.
- Or maybe, you want to rebatch to make your bar soap a little harder.
Whatever your reason, here’s how it’s done. (Spoiler alert: it’s easy.)
First, grate or chop your existing soap into smaller pieces and add everything to a crock pot. (If your initial batch turned out wonky, like it didn’t saponify completely, carefully slop your underdone soap mush into your crock pot.)
Next, turn your crock on and add a cup or so of water to reclaim your soap bits. (Low or high, the heat of your crock matters little: low only means you’ll be rebatching longer, high means you need to be more mindful of scorching.) You’ll be adding more water as needed, so no need to measure precisely.
Keep an eye on your crock pot for the next few hours, still occasionally and adding water to maintain a thick, almost porridige-like consistency.
If you’re rebatching because your soap still has active lye, leave your crock to chug along on low heat for a few hours to ensure your batch saponifies completely. If you’re rebatching for harder bars — think: the amateur soapmaker’s French-milling — or to add delicate essential oils that ordinarily wouldn’t survive single-step soapmaking (grapefruit, neroli, bergamot, etc.), once it’s fully melted and porridge-like, you’re good to go.
With a spatula, transfer your finished soap from your crock pot into a soap mould, or to save time, individual bar moulds. Let cool and leave out to cure for another 2-4 weeks, depending on your season and climate. (And I love the smell that curing soap fills my apartment with.)
Best of all, clean-up is a snap. Bring your crock into the shower with you and it can wash you as you wash it. After all, the only thing it’s dirty with is perfectly good soap.
Granted, rebatched soap isn’t always the sightliest soap in the world, but should you ever need to rebatch for any reason, now you know how. Enjoy!