Nutmeg Case

Trimyristin or glyceryl trimyristate occurs naturally in palm kernel oil, coconut oil, babassu oil and nutmeg fixed oil ('fixed' because it does not contain the volatile essential oils of nutmeg). It consists of a long chain carboxylic acid or fatty acid, myristic acid, combined with the trihydric alcohol, glycerol (propan-1,2,3-triol), through the ester linkage. It is one of a group of esters known as triglycerides or simple lipids. The chemical properties of lipids make them ideal components of membranes because they are amphipathic, which is they show hydrophilic and hydrophobic properties. Trimyristin is found in high concentrations in nutmegs, and no large concentrations of closely related esters are present. A product can thus be obtained by simple extraction and crystallisation without having to employ complex separation techniques that are often necessary in the isolation of plant products. Trimyristin isolated in multi-tonne quantities is used as a source of myristic acid, myristic alcohol and its derivatives that play crucial roles in the cosmetic industry. In 1993, Bristol-Myers Squibb's patent application for novel antiperspirant agents described esters of myristic alcohol as important ingredients that reduce the skin/clothes whitening effect.

Procedure

Place 10 g of ground nutmeg into a 250 cm3 wide-necked round-bottomed flask. Add 2-3 antibumping granules. Add 100 cm3 of diethyl ether and arrange for reflux (and with stirring) over a water bath (set at less than 50 oC) using a double-surface condenser. Use hot water from the tap and replace it whenever necessary so that the ether continues to boil. If the ether ceases boiling, add one or two anti-bumping granules before replacing the hot water. Heat the mixture at reflux (and stirring) for 30 to 45 minutes then filter the suspension through fluted Whatman No. 1 filter paper into a 100 cm3 conical flask to remove the nutmeg residue. Allow the solid residue to dry in a fume cupboard, weigh it and eventually dispose of it in the non-hazardous waste bin. Remove the diethyl ether from the filtrate on a steam bath in a fume cupboard. Add 40 cm3 of acetone and warm the mixture on a water bath to dissolve the yellow residue. Leave it to cool undisturbed at room temperature until crystals appear (15 to 30 minutes). Cool a small amount of acetone (20 cm3 is plenty) in ice water while waiting for crystals to appear.