Ciaglia Method Batch Resizing

[The Salford Pig]

Afternoon all,

Can anyone provide any insight on the calculations involved in resizing a batch when using the Ciaglia method?

Regular Mould volume e.g
Mould = 26cm x 7cm x 7cm = 1274 cm^3 (= 1274 ml = 1274 g)
1274 x 0.7 = 891.8 (892) g Total Oil weight to fill mould

Ciaglia Method
30-40% of Total Oil Weight
30% of 892 = 267.6 (268) g of soap shreds

892 g + 268 g = 1160 g Total Oils and Soap Shreds

So, with the above example the final oils and soap shreds will obviously create too much soap for the mould, so how do you resize the batch?

I've watched several videos of the Ciaglia method but none really go into detail about resizing the batch. The closest tutorial I have seen is from The Soap Artist but, she doesn't demonstrate the calculations behind the resizing after incorporating the soap shreds.

TIA

 

[DeeAnna]

Adding the total fats for the new batch plus the total weight of old soap won't give you a useful number, IMO. I handle confetti/ciaglia type batches like this --

Estimate the total weight of the "old soap."

Using a recipe that's typical for the one I would have used for that soap, back-calculate the weight of fats in the old soap. In other words, how much fat would I have to start with to make a batch of soap that has a total weight equal to the weight of old soap?

Reduce the fat used to make the new batch by the estimated weight of fat in the old soap.

As long as the recipe for the new batch is something similar to recipe used to make the old soap, this should come close.

The main error in this method is the amount of water loss in the old soap. I estimate water loss is somewhere around 10%, meaning if I start with 100 g of freshly made soap, it will weigh roughly 90 g after cure. You could use this estimated water loss to adjust the weight of "old soap".

I don't know how you can calculate it any closer than that. For that reason, I keep a few smallish molds handy in case there is some extra soap batter.