GUIDE TO S.A.P. VALUES IN SOAP MAKING

SAP values allow you to calculate the precise amount of sodium hydroxide required to fully saponify a given weight of oil/s. Below are both the SAP values of each oil you are likely to use, together with a guide to the mathemetics needed. There is also a simpler to use Saponification Chart which allows you to simply multiply the number of Ounces of each oil by a factor to give you the amount of sodium hydroxide in Ounces. To convert to grams simply multipy by 28.35.

Water is not a precise measurement. When calculating the amount of water to use in a soap recipe work on approximately 30-35% of the total weight of other ingredients used. i.e. 4lb of oils and 8.2oz sodium hydroxide will require approximately 1lb 8oz (1.5lb) of water.

SAP VALUES OF BASE OILS

Almond (sweet): 192.5
Apricot Kernel: 190.0
Avocado: 187.5
Babassu: 247.0
Beef Tallow: 197.0
Borage: 188.0
Calendula: 190.0
Castor: 180.3
Cocoa Butter: 193.8
Coconut: 268.0

Corn: 192.0
Evening Primrose: 191.0
Hazelnut: 195.0
Hemp Seed: 192.8
Jojoba: 97.5
Kukui Nut: 190.0
Lard: 194.6
Macadamia Nut: 195.0
Neem: 194.5
Olive: 189.7

 Palm Kernel: 219.9
Palm: 199.1
Peanut: 192.1
Pumpkin Seed: 193.0
Rapeseed: 174.7
Rosehip Seed: 193.0
Safflower: 192.0
Sesame Seed: 187.9
Shea Butter: 180.0
Soybean: 190.6

Sunflower Seed: 188.7
Wheatgerm: 185.0

Waxes

Beeswax: 88-100
Lanolin: 82-130
Lecithin: 110-140

HOW TO USE

To calculate the SAP value for a combination of oils first you need to calculate what percentage of the whole mixture of oils each oil makes up. For example. A mixture of oils consisting of 2 Lb Olive Oil: 1Lb 4oz Coconut Oil: 12oz Palm Oil will be: 50%Olive Oil: 31.25% Coconut Oil: 18.75% Palm Oil. Representing all the oils as 1, each percentage then becomes: 0.5: 0.3125: 0.1875

Next you multiply each figure by the Value in the table for each oil and add them all together. This will be:
0.5 (189.7) + 0.3125 (268) + 0.1875 (199.1) = 215.93 and divide by 1000 = 0.21593

Next, multiply the total 4Lb of oils by this figure:
4Lb x 0.21593 = 0.86Lb of sodium hydroxide.

Because SAP values pre-date our use of sodium hydroxide in soapmaking we have to make an adjustment. SAP values are for using potassuim hydroxide. To convert simply multiply the figure by 40/56.1:
0.86 x 40/56.1 = 0.61Lb

To convert into Ounces, multiply by 16: 0.61 x 16 = 9.76oz

Finally, as most of us work in grams this side of the Atlantic, convert this figure by multiplying by 28.35:
9.76 x 28.35 = 276 grams

Therefore, to produce a fully saponified soap using 2Lb Olive Oil: 1Lb 4oz Coconut Oil and 12oz of Palm Oil you will need 276 grams of Sodium Hydroxide.

To superfat your soap, simply discount this figure. As a guide, between 5 and 10% discount will produce a very good superfatted soap, i.e. 250g will be a satisfactory amount to achieve a good superfatted soap formula

 

SAPONIFICATION CHART

As an alternative to using traditional SAP values, the following chart can be used. Each figure is a multiplication factor. Simply multiply the quantity of oil/s by the figure for that oil to arrive at the amount of sodium hydroxide required to fully saponify that oil. If you're working in grams the figure you get will be in grams. If you're working in Lbs & Oz the figure you get will be in Oz and fractions of Oz. To convert Oz into Grams, multiply the resulting figure by 28.35. When working in combinations of oils, work out the figure for each oil separately and then add them together

Almond (Sweet): 0.136
Apricot kernel: 0.135
Avocado: 0.133
Babassu: 0.175
Beef Tallow: 0.140
Borage Oil: 0.136
Castor: 0.128
Cocoa Butter: 0.137
Coconut: 0.190

 Corn: 0.136
Evening Primrose: 0.136
Hazelnut: 0.136
Hemp Seed: 0.137
Jojoba: 0.069
Kukui Nut: 0.135
Lard: 0.138
Macadamia Nut: 0.139
Olive: 0.134

Palm Kernel: 0.156
Palm: 0.141
Peanut: 0.136
Pumpkin Seed: 0.135
Safflower: 0.136
Sesame: 0.133
Shea Butter: 0.128
Soybean: 0.135
Sunflower: 0.134

Wheatgerm: 0.132

Waxes

Beeswax: 0.069
Lanolin: 0.074

 

HOW TO USE

To use this simple chart, simply multiply the weight of each oil in Ounces by the value for that oil in the table above. This will give the amount of Sodium Hydroxide required to fully saponify that amount of that particular oil in Ounces. To convert that figure into grams, multiply by 28.35.

For combinations of oils, each oil should be calculated separately and then the figures added together to give the overall figure for the combination.