Your Questions Answered – Master Batching Soap Oils and Lye

Your Questions Answered - Master Batching Soap Oils and Lye


Q – What is master batching and how do I do it?

A – Master batching is simply making up a large batch of soapmaking oils and/or lye water ahead of time and using it as needed. In a large scale facility, making large batches and using the entire batch for each run is commonplace and is typically not referred to as a master batch. However, in an effort for the small soapmaker to save time to increase profit and to work more efficiently, soapmakers began mixing up their batches ahead of time.

Master batching is very simple to do. Most soapmakers prepare their batches in large buckets that will hold around 35lbs of oils. You can purchase this or reuse one that is now empty. Let’s say you have a recipe for a 5lb batch of soap and you want to create a master batch of 35lbs. You will multiply each oil by 7, since 5 will go into 35 seven times.

Let’s take a look at a recipe:

22 oz Olive oil x 7 = 154 oz
13.75 oz Coconut oil 76° x 7 = 96.25 oz
13.75 oz Palm oil x 7 = 96.25 oz
5.5 oz Sweet Almond oil x 7 = 38.5 oz

Melt the solid fats and combine them with the other oils in a large bucket. Each time you want to make a 5lb batch of soap, you will measure 55 oz from your master batch. Always stir the oils well before measuring, as the fats tend to settle at the bottom of the bucket. To make things easier, wrap your bucket in a bucket warmer. Each time you want to use the oils, plug the warmer in a few hours ahead of time. A warmer will bring your oil temperature to about 100°F while remelting any residual free floating fat. If you or someone you know is handy with a drill, you can fashion a spigot to bottom of the side of the bucket to easily measure your oils. This saves the time of measuring and melting oils for each individual 5lb batch.

You can do the same thing with your lye water. I only recommend this if you have a safe place to store it with no children or pets. If you want things ready to go with no calculations when making the soap, follow the same procedure for making the master batch of oils. Multiply everything by 7.

20 oz Distilled water x 7 = 140 oz
7.7 oz Sodium hydroxide x 7 = 53.9 oz

Mix your lye and water. Allow to cool to room temperature and store in large bucket or jugs made of HPDE plastic. Each time you make your soap using this recipe, you will measure 27.7 oz of lye water.

Or if you are cramped for space, you can make the lye water more concentrated. Reduce your water to half when premixing, and then add that back in when making the soap.

20 oz Distilled water x 7 = 140 oz ÷ 2 = 70 oz
7.7 oz Sodium hydroxide x 7 = 53.9 oz

Mix your lye and water. Allow to cool to room temperature and store in large bucket or jugs made of HPDE plastic. Each time you make your soap using this recipe, you will measure 17.7 oz of lye water mixture plus 10 oz of water.

There is no need to heat your lye water. Use it at room temperature. You can use this same method for mixing up large batches of other products you make, such as lotions and lip balms.