# Masterbatching fats

Masterbatching is the method of mixing ingredients in quantities large enough for multiple batches of soap. If you have a favorite blend of fats that you use a lot, you might want to make a masterbatched fat blend to simplify your soap making.

The size of your fat masterbatch is up to you. It could be large enough to meet your needs for the next several months. Or it could be enough for that marathon soap making session you are planning for next weekend.

1. Calculate the weight of each fat

Using your favorite soap recipe calculator, set the oil (fat) weight equal to the total masterbatch weight. If you want to make five batches of soap and each batch uses 500 grams of fat, then the total masterbatch weight is 5 x 500 = 2500 grams.

Consider increasing the total masterbatch weight by a small amount to allow for a bit of loss -- perhaps an extra ounce or two (30-60 grams). It is hard to completely scrape the fat out of a container and it seems like there are always a few drips.

Decide the percentages of the various fats you want in the masterbatch. Enter those percentages into the recipe calculator. You do not need to change any of the the other settings.

Click the "Calculate recipe" button if needed to calculate the recipe.

The resulting recipe should show the weight of each fat needed for the masterbatch. Ignore the weights of all other ingredients.

2. Get prepared

Make sure you have enough of each fat on hand. If you do not have enough of a given fat, reduce the masterbatch size or purchase more of the fat in low supply.

Decide how you want to store the masterbatched fat. Some people put it all in one large container and dip or scoop out enough fat for each batch. Other people portion the fat blend into individual batch-sized containers.

Make sure you have enough storage containers to hold the blended fat. A given weight of fat needs more room than you might expect. It will need about 11% more volume than the same weight of water.

Make sure the storage container(s) are very clean and dry and have a secure, liquid-tight seal.

Consider adding rosemary oleoresin extract (ROE) or another antioxidant such as BHT to the masterbatched fats for protection during storage. Some commercially prepared fats, such as lard, may already contain antioxidants so added ROE is not necessary, but others do not.

3. Make the masterbatch

Gently melt any solid fats, combine with the liquid fats, and add ROE if desired. Stir well and pour into container(s).

Let the fat cool to room temperature if necessary. Label the container(s) and store at room temperature until needed.

For extra long storage or if your blend contains a high percentage of polyunsaturated fat, you may want to keep the fat refrigerated or frozen if you have the room.

You can also make a masterbatched lye solution....