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Episode 2 - Shakers

Lanolin, Wool and Hand Cream
by Mike Bullivant

What is lanolin?
The properties of wool
How to make your own lanolin hand cream
What's the difference between a fat, an oil and a wax?
Did you know?
Further reading and websites

To make a soothing hand cream from whatever local resources we liked. All that gold panning at the river took a toll on our skin!

Lanolin What is lanolin?
Lanolin Lanolin is the smelly pale-yellow natural oil found on sheep's wool. As a waste product in wool processing, it's also known as wool oil, wool wax, wool fat, or wool grease. It's a natural water repellant — the function of which, as it's not too hard to guess, is to waterproof the sheep. Lanolin also has anti-fungal and antibacterial properties that protect the sheep's skin from infection. Derived from the animal's oil glands, lanolin is a mixture of wool fat and 25-30% water. Wool fat is a mixture of many different chemical compounds, including cholesterol and the esters derived from 'fatty' acids containing 18 to 26 carbon atoms.

Lanolin is used widely in the pharmaceutical and cosmetics industries. The oils in lanolin are similar in chemical composition to the oils secreted by human skin. What's more, it forms an emulsion with water that's easily absorbed by the skin, softening it and preventing it drying and cracking (this would explain why sheep shearers have such soft hands).

Strictly speaking, lanolin is a wax, not a fat or oil, and melts at a temperature between 100-107°F (38-42&def;C).

Mike boiling sheep woolTo extract the lanolin from unwashed wool you boil the wool in water for a few hours, adding salt to improve the yield of lanolin. Next, you reduce the solution by boiling off most of the water. After you filter any undissolved solid material from the hot solution and let it cool, you should be left with a pale-yellow waxy solid floating on the surface of the water. This is impure lanolin. You can purify it, as we did on the show, by taking the crude lanolin and shaking it with a mixture of olive oil and water. The impurities will dissolve into the water and the oil, leaving you with a solid layer of off-white, waxy 'purified' lanolin suspended between the oil and water.

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Purified lanolin The properties of wool
Wool has a very complex chemical and physical structure, which accounts for its uniqueness and versatility as a textile fiber. The fibers are made up of more than 20 amino acids, which combine to form long chains (polymers) of protein.

It's the internal structure of each woolen fiber — a three-dimensional corkscrew pattern, or helical 'crimp' — that gives wool its elasticity. The coiled springs of these molecular chains, with their permanent built-in 'memory,' makes the woolen fibers themselves coil-shaped and accounts for their enduring resilience.

Raw woolWool is superior to all other fibers in its ability to handle body moisture in both warm and cool environments. The porosity of the cells in the outer layers of wool fiber allows them to quickly and efficiently absorb and evaporate moisture. In fact, the fibers can absorb up to 30% of their own weight in moisture — ten times as much as any synthetic fiber — without feeling damp or clammy. The porous structure also explains why wool is such a good thermal insulator, not to mention the mesh of the fibers, which creates millions of air pockets that further help to regulate temperature and humidity.

Wool is a naturally strong fiber. It can bend back on itself 20,000 times without breaking. Compare this to cotton at 3,200 times, silk at 1,800, and rayon at only 75 times.

Due to its unique chemical structure and natural moisture content, wool is naturally fire-resistant. And despite its natural moisture content, wool's dry, porous nature repels mildew and dust mites.

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How to make your own lanolin hand cream
Here's a recipe for lanolin hand cream you may want to try at home.

3 Tbsp. lanolin
3 Tbsp. distilled water
3 Tbsp. grated beeswax
1/2 cup almond oil
3 Tbsp. witch hazel
1/8 tsp. borax powder

Mix the beeswax, lanolin and almond oil in an oven-safe dish and set the dish in a pan containing about an inch and a half of water. Place them in the oven and heat until the beeswax and lanolin have melted.

Mix the witch hazel, borax powder and distilled water in a saucepan. Heat the solution until just boiling and then slowly pour it into the melted beeswax/lanolin/almond oil mixture. Stir thoroughly and leave to cool.

When the mixture is completely cooled, you'll have a thick white cream to soften your skin.

How about making a scented hand cream? You could add almost any essential (aromatherapy) oil to it (but be careful to check your sensitivity to each oil beforehand, and follow any warnings on the labels). 5 to 10 drops of essential oil should be adequate for 3 ounces of cream. You could also add very finely chopped flower petals or herbs to the cream, to give it a different texture and aroma.

Tee tree We scented our lanolin hand cream with tee tree oil (sometimes referred to as 'tea tree oil'), not only because of its delicate nutmeg smell, but because it has a wide range of medicinal properties.

Tee tree oil is produced and contained in small sacs on the leaves of the tee tree plant. The sacs will rupture when heated and release their oil, which is how we obtained ours. It's been estimated that 2 tons of leaves will provide about 5 gallons of tee tree oil.

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What's the difference between a fat, an oil and a wax?
The difference between a fat and an oil is that a fat is solid or semi-solid at room temperature, while an oil is liquid.

There are also significant chemical differences between fats and oils. Generally speaking, solid fat contains more 'saturated' fatty acids, while oils usually contain 'unsaturated' fatty acids. Because they're made up of single chemical bonds, saturated fatty acids are flexible. The carbon-carbon double bonds in unsaturated fatty acids, on the other hand, are more rigid and less flexible. That means they're not as compact as those derived from saturated 'fatty' acids, and as a result, they're usually (liquid) oils.

Waxes are materials that can be molded when warm, but turn hard and sometimes brittle when cold. Waxes are insoluble in water and water-repellent. Natural waxes such as beeswax (from honeycombs) and lanolin (from wool) are esters of 'fatty' acids with alcohols containing only one alcohol (OH) group. This distinguishes them from vegetable oils and fats, which contain three OH groups.

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Did you know?

  • A wool mattress pad on your bed will eliminate dust mites, which can't survive in the natural lanolin of the wool.
  • A wool blanket can also help you sleep better. Tests have shown that the heart rate under a wool-filled comforter was always significantly lowered, while the humidity next to the skin was significantly lower 71% of the time.

What are other uses for lanolin?
Because it's an excellent water-repellent, lanolin is used on oil rigs as a corrosion inhibitor (an agent that slows down the rusting process). For the same reason, spare auto parts are sometimes coated in lanolin when they're put into long-term storage. And, of course, because it's chemically similar to many of the oils naturally produced by human skin, it's widely used in the pharmaceutical industry. In fact, when lanolin is mixed with suitable vegetable oils or soft paraffin, it makes a cream so good at penetrating the skin that it has been used as a 'carrier' to deliver pharmaceutical drugs subcutaneously (meaning just below the skin).

Lanolin can also be used as a lubricant and a leather finish and preservative. You'll even find lanolin in some varnishes and paints.

Further reading and websites::
Nutrition and Health, Book 3 of ST240 Our Chemical Environment, The Open University (2000), ISBN 0 7492 51433

University of Cincinnati - the chemistry of fats and oils explained.

Nutrition Australia - more on fats and oils from a nutritional angle.


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