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Scientific Soapmaking Kevin M. Dunn

Summer 2010

$Revision: 1.1 $

1

Acknowledgements Copyright © 2010 Kevin M. Dunn

Acknowledgements •

Mike Lawson/Columbus Foods

•

Scientific Soapmakers

2

Why Teach Soapmaking?

Why Teach Soapmaking? •

Thriving cottage industry

Why Teach Soapmaking?

Why Teach Soapmaking? •

Thriving cottage industry

•

Soapmakers generally come from a cooking/craft background

Why Teach Soapmaking?

Why Teach Soapmaking? •

Thriving cottage industry

•

Soapmakers generally come from a cooking/craft background

•

Soapmakers are interested in the chemistry of their craft

Why Teach Soapmaking?

Why Teach Soapmaking? •

Thriving cottage industry

•

Soapmakers generally come from a cooking/craft background

•

Soapmakers are interested in the chemistry of their craft

•

If gen-ed students can imagine themselves as soapmakers, they will become interested in the chemistry

Why Teach Soapmaking?

Why Teach Soapmaking? •

Thriving cottage industry

•

Soapmakers generally come from a cooking/craft background

•

Soapmakers are interested in the chemistry of their craft

•

If gen-ed students can imagine themselves as soapmakers, they will become interested in the chemistry

•

Experiments are designed to solve real-world problems

Let’s Make Soap

Let’s Make Soap •

1000 g Delight (an oil blend)

•

288 g Lye (500 ppt NaOH)

Let’s Make Soap

Let’s Make Soap •

1000 g Delight (an oil blend)

•

288 g Lye (500 ppt NaOH)

•

But how are we to weigh?

Weighing Synthetically

Weighing Synthetically •

Place bottle of lye on balance

•

Press tare button

•

Use cup to transfer lye to jug of oil

•

What if we overshoot?

•

What about the lye in the cup?

Let’s Make Soap

Let’s Make Soap •

1000 g Delight (already weighed)

•

288 g Lye (weigh synthetically into oil)

Let’s Make Soap

Let’s Make Soap •

1000 g Delight (already weighed)

•

288 g Lye (weigh synthetically into oil)

•

Shake vigorously for 60 seconds

•

Pour into styrofoam cups

•

Measure temperature

Oil and Water

Oil and Water

Glyceryl Trilaurate

Glyceryl Trilaurate

O O

O O

O O

Saponification

Saponification

Saponification

Saponification O

NaOH O

O

O

O

O

NaOH

NaOH

↓ Na

O

O OH

OH O

OH

Na

O Na

O O

Saponification

Saponification •

Oil + 3 NaOH = Glycerol + 3 Soap

•

Each molecule of oil requires 3 molecules of NaOH

Saponification

Saponification •

Oil + 3 NaOH = Glycerol + 3 Soap

•

Each molecule of oil requires 3 molecules of NaOH

•

What happens if you provide only 2 molecules of NaOH?

Saponification

Saponification •

Oil + 3 NaOH = Glycerol + 3 Soap

•

Each molecule of oil requires 3 molecules of NaOH

•

What happens if you provide only 2 molecules of NaOH?

•

What happens if you provide 4 molecules of NaOH?

Saponification

Saponification •

Oil + 3 NaOH = Glycerol + 3 Soap

•

Each molecule of oil requires 3 molecules of NaOH

•

What happens if you provide only 2 molecules of NaOH?

•

What happens if you provide 4 molecules of NaOH?

•

We measure oil and NaOH by weight, not by molecules

Saponification

Saponification •

Oil + 3 NaOH = Glycerol + 3 Soap

•

Each molecule of oil requires 3 molecules of NaOH

•

What happens if you provide only 2 molecules of NaOH?

•

What happens if you provide 4 molecules of NaOH?

•

We measure oil and NaOH by weight, not by molecules

•

Each gram of oil should require a specific weight of NaOH for complete saponification

Saponification Value

Saponification Value Theoretical saponification value of glyceryl tristearate: 1 mol oil ? g KOH = 1000 g oil 890 g oil = 189 ppt KOH µ

¶µ

3 mol KOH 1 mol oil

¶µ

56 g KOH 1 mol KOH

Experimental saponification value of tallow: 190-200 ppt

¶

Saponification Value

Saponification Value Theoretical sodium saponification value of glyceryl tristearate: 1 mol oil ? g NaOH = 1000 g oil 890 g oil = 135 ppt NaOH µ

¶µ

3 mol NaOH 1 mol oil

¶µ

40 g NaOH 1 mol NaOH

¶

Experimental sodium saponification value of tallow: 135-143 ppt

Saponification Value

Saponification Value • SV

= weight (mg) of KOH needed to saponify 1 g of oil

• SSV • AR

= weight (mg) of NaOH needed to saponify 1 g of oil

= weight (mg) of alkali actually used to saponify 1 g of oil

Saponification Value

Saponification Value • SV

= weight (mg) of KOH needed to saponify 1 g of oil

• SSV

= weight (mg) of NaOH needed to saponify 1 g of oil

• AR

= weight (mg) of alkali actually used to saponify 1 g of oil

• SV

of Delight is 211.5 ppt KOH

• SSV

of Delight is 150.8 ppt NaOH

Saponification Value

Saponification Value • SV

= weight (mg) of KOH needed to saponify 1 g of oil

• SSV

= weight (mg) of NaOH needed to saponify 1 g of oil

• AR

= weight (mg) of alkali actually used to saponify 1 g of oil

• SV

of Delight is 211.5 ppt KOH

• SSV

of Delight is 150.8 ppt NaOH

•

Since Lye is 500 ppt NaOH, we have used an AR of 144 ppt NaOH

•

Why?

Lye Discounting

Lye Discounting 11 Weeks Old

6 4 2 0 140

144

148

152

AR / ppt NaOH

156

TA / ppt NaOH

TA / ppt NaOH

1 Day Old 6 4 2 0 140

144

148

152

AR / ppt NaOH

156

Checking In

Checking In What are the temperature and consistency of your soap?

Measurable quantities

Measurable Quantities •

Finished soap • Total alkali • Moisture content • Hardness

Measurable quantities

Measurable Quantities •

Finished soap • Total alkali • Moisture content • Hardness

•

Raw materials • Saponification value • Lye concentration • Free fatty acid

Free Fatty Acid

Free Fatty Acid •

Real-world oils may contain “free” fatty acid

•

How can we measure it?

Titration

Titration

Titration

Titration •

Add 50 mL ethanol to Erlenmeyer flask

•

Add 4-5 drops 1% phenolphthalein

•

Add 4.18 ppt KOH until solution is faintly pink

•

Solution is now “neutral”

Weighing Analytically

Weighing Analytically •

Place coconut oil bottle on balance

•

Press tare button

•

Transfer 30-40 drops of oil to Erlenmeyer flask

•

Replace oil bottle on balance and read weight

Gravimetric Titration

Gravimetric Titration •

Place 4.18 ppt KOH bottle on balance

•

Press tare button

•

Add KOH to Erlenmeyer flask until faintly pink

•

Replace KOH bottle on balance and read weight

Acid Value

Acid Value YY.YY g standard ? g KOH = 1000 g oil 1.XX g oil ¶ µ YY.YY 4.ZZ ppt KOH AV = 1.XX µ

•

What is the Acid Value of your oil?

¶µ

4.ZZ g KOH 1000 g standard

¶

Acid Value

Acid Value YY.YY g standard ? g KOH = 1000 g oil 1.XX g oil ¶ µ YY.YY 4.ZZ ppt KOH AV = 1.XX µ

•

What is the Acid Value of your oil?

•

Why did we get different values?

¶µ

4.ZZ g KOH 1000 g standard

¶

Free Fatty Acid

Free Fatty Acid •

Free Lauric Acid = 3.570 AV

•

What is the Free Lauric Acid content of your oil?

Free Fatty Acid

Free Fatty Acid •

Free Lauric Acid = 3.570 AV

•

What is the Free Lauric Acid content of your oil?

•

Which oil would saponify quicker?

Extended Investigations

Extended Investigations •

Dreaded Orange Spots

Extended Investigations

Extended Investigations •

Dreaded Orange Spots

•

Seizing

Extended Investigations

Extended Investigations •

Dreaded Orange Spots

•

Seizing

•

Superfatting vs Discounting

Extended Investigations

Extended Investigations •

Dreaded Orange Spots

•

Seizing

•

Superfatting vs Discounting

•

The Water “Discount”

Lye Concentration

Lye Concentration •

What is the normal, correct, or standard lye concentration?

Lye Concentration

Lye Concentration •

What is the normal, correct, or standard lye concentration?

•

Ann Bramson, Soap: Making it, Enjoying it (1972) 25-27%, 26% average

Lye Concentration

Lye Concentration •

What is the normal, correct, or standard lye concentration?

•

Ann Bramson, Soap: Making it, Enjoying it (1972) 25-27%, 26% average

•

Susan Cavitch, The Soapmaker’s Companion (1997) 26-29%, 27% average

Lye Concentration

Lye Concentration •

What is the normal, correct, or standard lye concentration?

•

Ann Bramson, Soap: Making it, Enjoying it (1972) 25-27%, 26% average

•

Susan Cavitch, The Soapmaker’s Companion (1997) 26-29%, 27% average

•

Robert McDaniel, Essentially Soap (2000) 33-38%, 34% average

Lye Concentration

Lye Concentration •

What is the normal, correct, or standard lye concentration?

•

Ann Bramson, Soap: Making it, Enjoying it (1972) 25-27%, 26% average

•

Susan Cavitch, The Soapmaker’s Companion (1997) 26-29%, 27% average

•

Robert McDaniel, Essentially Soap (2000) 33-38%, 34% average

•

Anne Watson, Smart Soapmaking (2007) 30-37%, 33% average

The Soap Formula

The Soap Formula •

Lye = 50.00% NaOH, 50.00% distilled water

•

Coconut1000Lye348 Coconut1000Lye348Aq174 Coconut1000Lye348Aq348

The Soap Formula

The Soap Formula •

Lye = 50.00% NaOH, 50.00% distilled water

•

Coconut1000Lye348 (50.00% NaOH “Low-Water”) Coconut1000Lye348Aq174 (33.33% NaOH “Medium-Water”) Coconut1000Lye348Aq348 (25.00% NaOH “High-Water”)

Processing Soap

Processing Soap •

100 g oil + water + lye into 500 mL plastic bottle

•

Shaken 15 sec on a paint shaker

•

Gently swirled until trace

•

Poured into an Upland experimental mold

•

Incubated at 140◦F for 4 hours

Questions

Questions •

What do we want to know?

Questions

Questions •

What do we want to know?

•

Does the initial water portion affect the final moisture content?

•

Does it affect the curing time?

•

Does it effect the hardness of the soap?

•

Is there a danger of separation?

What Can We Measure?

What Can We Measure? •

Moisture content of soap over time

•

Hardness of soap over time

•

Alkalinity of soap over time

•

Separation of soap

What Can We Measure?

What Can We Measure? •

Moisture content of soap over time Initially from formula, follow weight loss over time

•

Hardness of soap over time

•

Alkalinity of soap over time

•

Separation of soap

What Can We Measure?

What Can We Measure? •

Moisture content of soap over time Initially from formula, follow weight loss over time

•

Hardness of soap over time Soil penetrometer

•

Alkalinity of soap over time

•

Separation of soap

What Can We Measure?

What Can We Measure? •

Moisture content of soap over time Initially from formula, follow weight loss over time

•

Hardness of soap over time Soil penetrometer

•

Alkalinity of soap over time Titration with 5 ppt citric acid

•

Separation of soap

What Can We Measure?

What Can We Measure? •

Moisture content of soap over time Initially from formula, follow weight loss over time

•

Hardness of soap over time Soil penetrometer

•

Alkalinity of soap over time Titration with 5 ppt citric acid

•

Separation of soap Hardness of top and bottom of bar Alkalinity of top and bottom of bar

Moisture

Moisture •

Coconut1000Lye348Aq348

•

Total weight 1696 g

•

Water weight (174 + 348) = 522 g

•

Initial moisture = (522/1696) = 0.308 = 30.8% = 308 ppt

Moisture

Moisture •

Coconut1000Lye348Aq348

•

Total weight 1696 g

•

Water weight (174 + 348) = 522 g

•

Initial moisture = (522/1696) = 0.308 = 30.8% = 308 ppt

•

Initial bar weight 141.32 g; Final weight 113.17 g

•

Weight loss (28.15/141.32) = 0.199 = 19.9% = 199 ppt

•

Final moisture = 308 - 199 = 109 ppt

Penetrometer

Penetrometer

Smaller foot used for hard soaps.

Titration

Titration

How many grams of acid required to titrate a given weight of soap?

Total Alkali

Total Alkali Y.YY g acid 5 g H3Cit ? g NaOH = 1000 g soap 1.XX ¶ µ g soap 1000¶ µg acid ¶ µ 3 mol NaOH 40.00 g NaOH 1 mol H3Cit 192.12 1 mol NaOH µ g H3¶Cit 1 mol H3Cit Y.YY TA = 3.123 ppt NaOH 1.XX µ

¶µ

¶

Palm Oil

Palm Oil •

Low, Medium, and High Water soaps

•

Identical in other respects

•

Moisture and hardness measured weekly for 60 days

•

Alkalinity measured at beginning and end

Palm Oil

Palm Oil Batch Code KMD2007.12.27 A Palm1000 Lye286 B Palm1000 Lye286Aq143 C Palm1000 Lye286Aq286

111 200 273

Moisture A B C

200

0

30 Days

Alkali (ppt NaOH) Initial Final Top Bottom Top Bottom 1.8 4.9 0.3 0.9 1.8 1.4 -1.7 -0.2 0.5 0.3 -1.7 -0.1 Hardness

10

100 0

54 60 74

kg/scm

300 ppt

Moisture (ppt) Initial Final

60

5 0

0

30 Days

60

Coconut Oil

Coconut Oil Batch Code KMD2008.1.8

Moisture (ppt) Initial Final

D Coconut1000Lye348 E Coconut1000Lye348 Aq174 F Coconut1000Lye348 Aq348 Moisture D E F

200

Hardness 10

100 0

0

30 Days

41 88 109

kg/scm

300 ppt

129 229 308

Alkali (ppt NaOH) Initial Final Top Bottom Top Bottom 0.4 0.5 -0.6 -0.3 -0.1 -0.2 -1.7 -1.0 0.1 0.2 -1.8 -0.4

60

5 0

0

30 Days

60

Olive Oil

Olive Oil •

Medium and high water soaps separated

•

What can I do to accelerate trace?

Olive Oil

Olive Oil •

Medium and high water soaps separated.

•

What can I do to accelerate trace? Add clove oil.

Olive Oil

Olive Oil Batch Code KMD2008 Olive1000Lye264 Olive990 Clove10 Lye259 Olive990 Clove10 Lye259 Aq130 Olive990 Clove10 Lye260 Aq260 Moisture 1.7A 3.5A 3.5B 3.5C

300 ppt

104 103 187 256

200

0

30 Days

Alkali (ppt NaOH) Initial Final Top Bottom Top Bottom 0.3 0.2 -3.2 -0.4 -0.4 -0.7 -0.7 -0.7 -0.4 -0.4 -0.8 -0.7 -0.7 6.2 -1.1 -0.2 Hardness

10

100 0

36 43 61 67

kg/scm

1.7A 3.5A 3.5B 3.5C

Moisture (ppt) Initial Final

60

5 0

0

30 Days

60

Delight

Delight •

Delight = Olive390Palm280Coconut280Castor50

Delight

Delight Batch Code KMD2008.2.17

Moisture (ppt) Initial Final

A Delight1000Lye288 B Delight1000Lye288 Aq144 C Delight1000Lye288 Aq288

112 201 274

Alkali (ppt NaOH) Initial Final Top Bottom Top Bottom -0.2 0.2 -1.0 -0.4 -0.4 0.3 -3.1 -0.9 -0.9 0.9 -3.7 -1.3

48 89 104

Moisture A B C

200

10 kg/scm

300 ppt

Hardness

100 0

0

30 Days

60

5 0

0

30 Days

60

Delight

Gel Phase •

Delight1000Lye288Aq50 Tmax 151◦F after 180 minutes Never reached gel phase Total alkali: 1.3 ppt (top), -0.2 ppt (bottom)

Delight

Gel Phase •

Delight1000Lye288Aq50 Tmax 151◦F after 180 minutes Never reached gel phase Total alkali: 1.3 ppt (top), -0.2 ppt (bottom)

•

Delight1000Lye288Aq100 Tmax 156◦F after 165 minutes “Very dry vaseline” at 145◦F after 210 minutes Total alkali: 0.5 ppt (top), 0.1 ppt (bottom)

Delight

Gel Phase •

Delight1000Lye288Aq200 “Vaseline” with beads of oil at 151◦F after 195 minutes Tmax 154◦F after 210 minutes Total alkali: -0.2 ppt (top), 4.0 ppt (bottom)

Delight

Gel Phase •

Delight1000Lye288Aq200 “Vaseline” with beads of oil at 151◦F after 195 minutes Tmax 154◦F after 210 minutes Total alkali: -0.2 ppt (top), 4.0 ppt (bottom)

•

Delight1000Lye288Aq250 Tmax 156◦F after 165 minutes “Jello” with layer of oil at 156◦F after 180 minutes Total alkali: -0.2 ppt (top), 8.7 ppt (bottom)

Delight

Gel Phase Moisture Content (ppt) 200

Temperature (oC)

100 80 60

200

neat (gel)

160

curd + neat

120

40 20 0

300 Temperature (oF)

100

80

curd (solid) Aq0

Aq144

Aq288

40

Soap phases determined by Differential Scanning Calorimetry

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content?

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time?

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time? Yes, more water initially lengthens the curing time.

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time? Yes, more water initially lengthens the curing time.

•

Does it effect the hardness of the soap?

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time? Yes, more water initially lengthens the curing time.

•

Does it effect the hardness of the soap? Yes, high-water soaps are softer initially, but may equilibrate to the same final hardness as low-water soaps.

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time? Yes, more water initially lengthens the curing time.

•

Does it effect the hardness of the soap? Yes, high-water soaps are softer initially, but may equilibrate to the same final hardness as low-water soaps.

•

Is there a danger of separation?

Conclusions

Conclusions •

Does the initial water portion affect the final moisture content? Probably not, though moisture may take more than 60 days to equilibrate.

•

Does it affect the curing time? Yes, more water initially lengthens the curing time.

•

Does it effect the hardness of the soap? Yes, high-water soaps are softer initially, but may equilibrate to the same final hardness as low-water soaps.

•

Is there a danger of separation? Yes, high-water soaps are more prone to separation than low-water soaps.

Checking In

Checking In What are the temperature and consistency of your soap?

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

•

Each student paid $50 fee.

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

•

Each student paid $50 fee

•

Students self-organized into four “firms”

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

•

Each student paid $50 fee

•

Students self-organized into four “firms”

•

Firms “bought” all equipment and supplies at list price

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

•

Each student paid $50 fee

•

Students self-organized into four “firms”

•

Firms “bought” all equipment and supplies at list price

•

Students kept 90% of the soap produced

Scientific Soapmaking Class

Teaching Scientific Soapmaking Economically •

Spring 2010, 26 students

•

Each student paid $50 fee

•

Students self-organized into four “firms”

•

Firms “bought” all equipment and supplies at list price

•

Each student kept more than $50 worth of soap

•

Department kept all equipment and leftover supplies—no net cost to the Department

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

•

Production period approximately one 8-hr day

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

•

Production period approximately one 8-hr day

•

Juried soap sale used to “sell” production soap

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

•

Production period approximately one 8-hr day

•

Juried soap sale used to “sell” production soap

•

Each firm used GnuCash to track income and expenses

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

•

Production period approximately one 8-hr day

•

Juried soap sale used to “sell” production soap

•

Each firm used GnuCash to track income and expenses

•

495 bars produced, 382 bars “sold” for $1746

Scientific Soapmaking Class

Teaching Economic Soapmaking •

90 min lecture, 90 min lab each week

•

4 weeks startup, 5 weeks production, 4 weeks R&D

•

Production period approximately one 8-hr day

•

Juried soap sale used to “sell” production soap

•

Each firm used GnuCash to track income and expenses

•

495 bars produced, 382 bars “sold” for $1746

•

Return on Equity: 47%, 88%, 102%, 118%

Scientific Soapmaking Class

Juried Soap Sale

Rack used for curing, then displaying production soap

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

•

Jurors kept the soaps they selected

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

•

Jurors kept the soaps they selected

•

For each soap selected, 9 more “sold” at the same price

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

•

Jurors kept the soaps they selected

•

For each soap selected, 9 more “sold” at the same price

•

Firms were allowed to change prices daily

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

•

Jurors kept the soaps they selected

•

For each soap selected, 9 more “sold” at the same price

•

Firms were allowed to change prices daily

•

No real money changed hands, 90% of soap returned

Scientific Soapmaking Class

Juried Soap Sale •

Each firm set up a display of products with prices

•

Each juror had $30 to “spend”

•

Jurors kept the soaps they selected

•

For each soap selected, 9 more “sold” at the same price

•

Firms were allowed to change prices daily

•

No real money changed hands, 90% of soap returned

•

Average value of returned soap: $60/student

Scientific Soapmaking Class

Grading Scientific Soapmaking •

11% Homework

•

11% HSMG CP/HP Level I Exam

•

11% HSMG CP/HP Level II Exam

•

22% Cumulative Exam

•

11% Return on Equity

•

11% Analytical Project Report

•

22% Quarterly Report for Firm

Scientific Soapmaking Class

Organizations •

The Handcrafted Soap Makers Guild (www.SoapGuild.org)

•

The Saponifier (www.Saponifier.com)

•

Scientific Soapmaking (www.ScientificSoapmaking.com)