Mid-December and I am sitting beneath a cloudless blue sky, the chilling frost having been chased away by the warming sun. A wedge of  Canada geese honk their urgent way to breakfast in the nearby water meadows as a covey of red-legged partridges scurries about the garden emitting a rhythmically repeated, hoarse ‘kuchek-CHER-kuchek-CHER, which draws the attention of Mick. Knowing that he cannot fly, the bustling little birds opt, rather sportingly I think, to run rather than go airborne, leaving the Irish terrier a little bewildered and rather out of puff. Ah well, I can see him think as he takes up vigil behind a nearby hornbeam tree, I shall get my chance to put up a fine flying display when a chirm of chaffinches, or a murmuration of starlings, joins that unwitting dole of doves and host of sparrows sifting through the parrots’ discarded seed. Meanwhile a nye of pheasants arrives to watch the fun.

Doubtless you will have noted my predilection for collective nouns when mentioning groups of different birds, a useless grammatical fact taught me by an ornithologically enthusiastic English master when I was a boy. Although I did not know it then, many of these terms for groups of birds belong to 15th-century lists of ‘proper terms’, notably that in the Book of St. Albans attributed to Dame Juliana Barnes (1486). Many of these are fanciful or humorous terms which probably never had any real currency, according to The Concise Oxford Dictionary, but I cherish them.

Jumping Jehoshaphat! Mick has just caught a rabbit! How on earth did he manage that?

Lurking behind the columnar form of the heartleaf hornbeam (Carpinus cordata), the unsuspecting cony can’t have seen him. No youngster, it’s a fully grown adult. Mick can’t believe his luck, and brings the poor thing readily to hand for safe release. Henceforth, this medium-sized attractive tree, which was introduced into Europe from Japan less than 150 years ago, will no doubt be his favourite hiding place. In its natural habitat the tree grows amidst mixed woodland in mountainous regions but, since its introduction here it has become widely distributed in botanic gardens, but is still fairly rare in ordinary gardens.

Previously, he had favoured as his lair the cover of an older introduction that was discovered by the German botanist and explorer P.S. Pallas in 1780, a weeping silver-leaved pear (Pyrus salicifolia) but, as these are relatively short-lived, he has probably made a sound choice!

    
All of which reminds me how much things have changed. So often, at this time of year, I would be in the local Tesco to collect their discarded boxes as we would have run out of our own supply due to the Christmas rush. I would then spend hours in the local post office sticking stamps on parcels as an ever-growing queue behind me became increasingly frustrated. Out in all weathers, I would dash hither and thither to collect oils, bottles and assorted paraphernalia from around the country, as courier companies were few and far between back then and Royal Mail was disinclined to handle anything much larger than a shoebox. True, some suppliers did have their own transport but, if you had failed to phone your order in on time, it would be another month before they came your way again, and there was a limit to how much we could store under the bed anyway!

The cost of freight forwarders was way beyond our budget and so I would go to Heathrow to clear the goods myself. Inevitably, there was always a consignment from some exotic spot (Madagascar springs readily to mind) on Christmas Eve, but this Yuletide bonanza could present a hazard. If you did not clear goods immediately, they would be stuck in a warehouse over the Christmas period to incur hefty storage charges. Thoughts of a pre-Christmas drink in the warmth of a nearby pub had to be quickly put aside as I huddled in the chill of the freight terminal. It would be almost Christmas Day before I returned home. Nevertheless, despite all, I rather miss those early days!       
Ruminating over Rhubarb.
Rhubarb! I used to loathe the stuff. At preparatory school it was a staple pudding, served in crumbles, pies, tarts, and even ice cream. Perhaps, if cook had added a little sugar, I might have liked it more but, as it was, it was unbelievably tart. What’s more the younger boys had to assist with its cultivation. I dreaded the arrival of the local farmer with his horse and cartful of manure. Rank and steaming, it would be dumped at our feet for immediate spreading over and around acres of boxes under which young rhubarb plants were growing. Why, I wondered, did this extra-curricular activity always take place in pouring rain. Put your backs into boys!, the headmaster would shout with glee from the shelter of his umbrella. On more than one occasion, I was tempted to hurl a forkful of the evil muck at him, but that would have decreed an immediate ‘six of the best’ and I was in enough agony already. I couldn’t wait for my eleventh birthday,to be rid of this both onerous and odorous task!

Of course, rhubarb can be quite palatable. I like mine simmered on the hob in a little water for about 10 minutes, with a little light muscovado or demerara sugar, orange zest and orange-flower water. It can also be a good accompaniment with meat and fish. A puree of the green summer stalks really cuts through the rich flesh of roast pork and oily fish, and a mound of almost unsweetened rhubarb, to use up the stalks before they become too tough for a fool or a tart, goes surprisingly well with roast duck. If neither fish nor fowl is to your liking, try the stalks baked with a little honey and eaten with yoghurt.

As I gleaned as a small boy, the finest flavoured early stalks are those that have been forced, which means little more than placing an old box over the crowns to keep out the light and to protect the new shoots. The chunkier stalks of the summer crop lack the more delicate flavour of the early crop, and are more acidic.

Commercially, forced rhubarb is grown in heated, windowless sheds mostly around Wakefield in Yorkshire, an area known as the Rhubarb Triangle. In order to prevent the light from infiltrating the sheds and sending the pale yellow leaves green as they unfurl, the stalks are picked by candlelight. Apparently, if you choose the right night to visit, you can hear the whispered crackle of the leaves unfurling. However, it didn’t all start in the Rhubarb Triangle.

About 1777, Hayward, an apothecary, of Banbury, close to here, started the cultivation of rhubarb with plants of Rheum rhaponticum, raised from seeds sent from Russia in 1762, and produced a drug of excellent quality, which used to be sold as the genuine rhubarb, by men dressed as Turks. The Society for the encouragement of Arts, Manufactures and Commerce exerted itself for many years in promoting the cultivation of rhubarb. It granted medals not only to this original pioneer, but also, some years on, to growers of rhubarb in Somerset, Middlesex, and Yorkshire.

Rhubarb stems did not come into general food use until about the 1830s. A pioneer grower, Joseph Myatt, of Deptford, in 1810, sent five bunches of rhubarb to Borough Market and was only able to dispose of three. But he persevered in his efforts to create a market for rhubarb, raised better varieties, and a few years later, rhubarb had etablished itself with the  public as a culinary plant. However, it was soon realized that the use of rhubarb as food was sometimes accompanied by some risk to health.

Lindley, in his Vegetable Kingdom of 1846, remarks that oxalic acid exists in both Docks and Rhubarb, and that the latter contains also an abundance of nitric and malic acid, and he goes on to say that whilst these give an agreeable taste to the rhubarb when cooked, he considers them ill-suited to the digestion of some persons.

The chemical constituents of rhubarb leaves were not fully ascertained until about a century later when an official analysis was undertaken on the orders of the Home Office, in consequence of fatal and injurious effects having resulted from eating the leaves cooked as spinach. Lindley was right: the leaves contain 0.3% oxalates of potassium and calcium. It was concluded that it was possible the cases of poisoning occurred only in persons specially susceptible to oxalic poisoning, as there were also many cases reported of no harm ensuing from use of rhubarb leaves as a vegetable. Nevertheless, today, it is generally accepted that the leaves of rhubarb should not be ingested, but the stalks are safe.

However oxalic acid may provide a ray of hope for beekeepers, as they believe that it attacks the varroa mite, a common parasite that many suspect could be killing Britain’s honey bees. Medicines containing the acid are already being manufactured by a handful of small specialist companies in continental Europe but none has been licensed for sale in Britain, probably because of the high cost of licensing fees. Beekeepers are now urging the Environment Secretary and the veterinary medicine regulators to ease the rules, by waiving the fees, to enable the treatment to be made available legally in this country. Interestingly, oxalic acid is also found in spinach, but in much smaller concentrations.  

For medicinal purposes, Mrs. Grieve observed eighty years ago, in her classic A Modern Herbal, ‘We still depend upon Northern China and Tibet for rhubarb; that grown in the English climate, near Banbury, does not command a high price in the market, although its medicinal properties are the same as those of the Chinese roots.’ Well, it seems that that is still the case today.

Chinese rhubarb (Rheum palmatum), or Da Huang in Chinese, was first mentioned in the 1st century AD Chinese Materia Medica and has been grown in the West since 1732. It is one of the relatively few herbs still used today in conventional as well as herbal medicine, and is listed in the British Pharmacopoeia of 1988. Prized as the most useful purge, safe even for young children due to its gentle action, it has been used in China for over 2,000 years and is an extremely effective treatment for many digestive problems. Paradoxically, it is a laxative when taken in large doses but has a constipating effect in small measures.

The rhizome, which has an astringent and unpleasant taste, contains anthraquinones (3-5%), tannins (5-10%), flavonoids, phenolic acids, and calcium oxalate. Its medicinal value is largely due to the irritant, laxative and purgative properties of the anthraquinones and in large doses the rhizome is strongly laxative. However, the high levels of tannins counterbalance the laxative action, and in small doses the tannins predominate, causing a constipating effect. The herb can also be applied to burns, boils and carbuncles. It is a tonic and mild appetite stimulant and is a useful mouthwash for ulcers, as decoctions of the root have been shown to be effective against Staphylococcus aureus.

Help with Molluscum contagiosum.
I have an enquiry about Molluscum Contagiosum. Do you have any advice on how to treat this condition on twins who are six years old? They have had the condition for 9 months. Their GP has said just let it run its course, and this could take up to 4 years. Their mother is feeling a bit frantic about it as it has spread to the little girl’s genital area, and she worries about her children passing it on to others, e-mailed Angela Secretan.

Molluscum contagiosum is a common disease of the skin, mainly affecting children. Characterized by papules less than 5mm in diameter, each with a central depression, the disease is caused by a poxvirus and is spread by direct contact. Untreated, the papules usually disappear in 6-9 months. Obviously, in this particular case, the disease is proving more persistent. Fortunately, I recollect reading a case study by Dr. Daniel Penoel, who has dedicated his three-decade career to the therapeutic use of essential oils.

By the way, I have just read in In Essence, the house Journal of the International Federation of Professional Aromatherapists, that Dr. Penoel, a medical doctor and pioneer of medical aromatherapy, has been researching into new physics to find the missing link between medical aromatherapy and ‘soft’ aromatherapy. His research has led him “to find a way to bridge the gap between those two kinds of aromatherapy.” He calls this bridge Quantum Aromatherapy, and has registered it as his trademark. Next summer, from 11th to 14th July in the Drome Valley in France, he will be offering training to English-speaking therapists. In the course, so he says, he will crack the health code and, by challenging the way we understand essential oils, will revolutionize the current ways of utilizing aromatherapy. 

To find out about course costs, a detailed programme, and bookings, including early bird discount, e-mail penoelschool@gmail.com or call 0033 4 75768342. As a taster, Dr. Penoel is to contribute an article on Quantum Aromatherapy to the Spring 2009 edition of In Essence.

Now back to the case in hand, which illustrates well Dr. Penoel’s skills.

A young boy was suffering from Molluscum contagiosum. His whole body, including his genitals, was covered with papules; he was feverish and screaming day and night. The boy was also prone to eczema and allergic reactions. Not only was the child’s medical condition assessed, but the family were asked to undertake the therapeutic programme prescribed.

First, a toxic free diet was established to help the detoxification process which accompanies any infectious disease. Then, because of the severity of the condition, undiluted Melissa hydrolat (Melissa officinalis L.) was sprayed around the boy, providing relief for the first time in many days of intense suffering. Melissa is antiviral, antiinflammatory, and calming.

After that, the following essential oils were chosen and blended: Roman Chamomile (Chamaemelum nobile (L.) All.), for its antiinflammatory, calming, and vulnerary properties; German Chamomile (Matricaria recutita L.), which is cicatrizant, antiallergic, and antiinflammatory; Tea Tree (Melaleuca alternifolia (Maiden & Betche) Cheel), because it is not only analgesic, antiinfectious, antiinflammatory and antiviral, but also immunostimulant; Sweet Thyme (Thymus vulgaris ct. linalol L.), being as it is antiinfectious, antiinflammatory, antiseptic, antiviral, and an immunostimulant; and, finally, Juniper Berry (Juniperus communis L.), an analgesic, antiseptic, antiviral, and depurative oil. This blend was to be applied in three different ways:

5% in a 95% blend of vegetable oils - Calendula (Calendula officinalis) (60%), St. John’s Wort (Hypericum perforatum) (25%) and Tamanu (Callophyllum inophyllum) (10%), which the parents were asked to apply on each papule, using a fine paint brush.

1 drop blended in honey to be taken internally six times per day.

3 drops, diluted in vegetable oil, were put in capsules, to use as suppositories.

A second blend of essential oils was made with equal quantities of Cajuput (Melaleuca cajuputi Powell), Tea Tree (Melaleuca alternifolia Maiden & Betche) Cheel), and Red Myrtle (Myrtus communis L.). This was to be applied without dilution on the sole of each foot six times a day.

After the first treatment at the clinic, the blends and suppositories were given to the parents to continue treatment at home; the spraying kit was lent to them for the period of intensive care. They were asked to phone every day to report the boy’s progress and to return to the clinic after 9 days.

After three days the problem had improved enormously. The treatment was continued, but reducing the number of applications per day. When the family returned to the clinic nine days later the young boy’s skin was almost perfect and he had regained his vitality. A truly remarkable and speedy recovery! Dr. Penoel himself attributes much to the dedication of the little boy’s parents.

Concrete, or concentrate?
On the third sheet of your last Newsletter [No. 201] you have mentioned “concrete” several times. My guess is that you mean “concentrate”. Is it a competition? Is there a prize? I was e-mailed today.

Perhaps now is a good time to review briefly ‘extracts’, which should not be confused with ‘extraits’, for they are another matter altogether.

Extracts of fragrance and flavour substances obtained from plants are termed pomades, concretes, absolutes, resinoids, or tinctures according to their method of preparation. Pomades consist of fats that contain fragrance substances and are produced by the hot or cold enfleurage of flowers. Hot enfleurage is the oldest known procedure for preserving plant fragrance compounds. In this method, flowers, or other parts of a plant, are directly immersed in liquid or molten wax.

In cold enfleurage, the volatile components released by flowers into their surroundings are absorbed with fats over a longer period of time. This industrial procedure was developed in southern France in the 19th century for the production of high-grade flower concentrates. It involves the application of fresh flowers to a fat layer, consisting of a mixture of specially refined lard and beef tallow, which is spread on a glass plate in a closed container. The trays or stacks of greased plates, with the flowers adhering to the fat, are left for 24 hours. The flowers are then picked off by hand, and a new batch of flowers is sprinkled on the same layer of fat. The spent flowers are extracted with a hydrocarbon solvent to produce Concrete de Chassis, which in turn is processed into Absolute from Chassis. After many batches, each consisting of 24 hours of flower treatment on the trays (and up to 36 batches on the same layer of fat), the fragrance-saturated fat (known as corps gras) is removed from the plates or trays (the chassis). The saturated fat is known as pommade in French. This method, however, has been almost completely replaced by the less tedious technique of solvent extraction.

Concretes are prepared by extracting fresh plant material with nonpolar solvents (e.g., toluene, hexane, petroleum ether). On evaporation, the resulting residue contains not only volatile fragrance materials, but also a large proportion of non-volatile substances including waxy compounds. For this reason, concretes, like pomades, are not completely soluble in alcohol and, thus, find limited use as perfume ingredients. However, they can be used in the scenting of soaps.

Concretes, which are actually intermediate products, are prepared mainly from flowers (rose, jasmine, tuberose, jonquil, ylang-ylang, mimosa and boronia, etc.), but also from other plant materials (lavender, geranium, lavandin, violet leaves, clary sage, oak moss, etc.). For example, a yield of about 0.3%, based on the starting flower material, is obtained in the production of jasmine concrete.

Absolutes are prepared by taking up concretes in alcohol. Compounds that precipitate on cooling are then removed by filtration. After having evaporated the alcohol, a wax-free residue called absolute is left behind.

Absolutes are completely soluble in ethanol and, therefore, can be freely used as perfumery ingredients. Nevertheless some, in exceptional cases, can be solid or semi-solid (e.g., clary sage absolute, beeswax absolute, bruyere absolute, etc.). The concrete usually yields about 50% absolute. In rare cases, absolutes can be obtained directly by extracting the plant material with alcohol, for example tonka bean.

Resinoids are prepared by extracting plant exudates (balsams, oleo gum resins, natural oleo resins, and resinous products) with solvents such as methanol, ethanol, or toluene. Yields range from 50 to 95%. These products are highly viscous and are sometimes diluted (e.g. with benzyl benzoate or phthalates) to improve their flow and processing properties.

Resinoids mainly consist of non-volatile, resinous compounds and are used primarily for their excellent fixative properties.

However, the resinoids about which I am writing should be distinguished from prepared oleoresins (e.g., pepper, ginger, and vanilla oleoresins), which are concentrates prepared from spices by solvent extraction. The solvent that is used depends on the spice; currently, these products are often obtained by extraction with supercritical carbon dioxide. Pepper and ginger oleoresins contain not only volatile aroma compounds, but also substances responsible for pungency.

Tinctures are alcoholic solutions that are prepared by treating natural raw materials with ethanol or ethanol-water mixtures. They can also be obtained by dissolving other extracts in these solvents. Tinctures are sometimes called infusions.

There is no general rule governing the strength of perfumery or flavour tinctures, unlike pharmaceutical tinctures. Therefore, tinctures do not always represent the total amount of natural raw material from which they are prepared, as the natural raw material may not be completely exhausted before it is thrown away.

Most perfumery tinctures are made by maceration, from gum-resins, natural oleo-resins, etc. A maceration is a soaking of the comminuted material in alcohol or diluted alcohol until the cellular structure of the raw material is thoroughly penetrated, and the soluble portions softened and dissolved. The maceration lasts several days, sometimes up to two weeks, during which time the raw material is frequently agitated in the alcohol. Other tinctures, such as ambrette seed and vanilla fruits, are prepared by percolation. Percolation is a process during which the comminuted raw material is put in a container and then has its soluble constituents removed by the descent of a solvent through it. In a few cases, tinctures are made by simple solution, but these are dilutions rather than real tinctures, although the term “tincture” is still applied to this type of preparation.    

Having re-read this, I can now understand why Alan Balfour thought that I might have meant “concentrate” rather than “concrete”, as I’m a bit confused myself, but no prize all the same! Still,lest any think that I might mean “gruyere” rather than “bruyere” in my bit about absolutes, let me explain now.

Bruyere Absolute.
Gruyer e is, of course, a cheese from the Gruyere valley in the Swiss Canton of Fribourg. It is also made in the Swiss Cantons of Vaud and Neuchatel. Although sometimes cheesemongers advertise ‘a genuine Gruyere from Emmenthal’, named after the high Emme valley in Berne Canton, the true Gruyere is only made in French Switzerland.

Bruyere, on the other hand, is a perfume material extracted from the roots of various species of heather shrubs. The French term, “bruyere”, actually refers to all kinds of shrubs growing on barren, arid, wasteland. However, certain species have distinguished themselves by their ability to grow to a considerable size and substantial age.

Erica arborea L. grows all over the Mediterranean countries, and it is particularly common in Algeria, Corsica, and in the Canary Islands. It may grow to an age of several hundred years and a height of eighteen metres. The roots of such old species are collected for the purpose of carving tobacco pipes (“Briar” wood). The unusually high content of ashes in the wood prevents it from burning through in a pipe.

Waste wood from the pipe carving factories used to be discarded, but it is now very occasionally used for the production of bruyere absolute. This absolute is a greenish-yellow, solid but soft mass, resembling araucaria or guaiacwood oils. It has a very mild, woody-green, slightly spicy odour. Sadly, I haven’t come across any for years.

Ultrasonic extracts.
Just as I was about to finish this Newsletter the phone rang. What do you know about ultrasonic extracts?, the office asked. Good heavens! Back again to methods of extraction!

Ultrasonic extracts are prepared flavour materials, or, in a few cases, perfume materials. Several methods of extracting natural raw materials with the aid of supersonic sound vibrations have been described in the scientific literature, and many extractors have been patented.

It is claimed that this method of extraction gives higher yields; reduces the amount of solvent required; greatly improves the flavour or odour in the sense that they become more true-to-natuire; reduces the extraction time considerably; and makes possible an extraction with water or low proof alcohol where this is otherwise not too effective.

The capacity of the extractors was originally a major problem, which limited the popularity of this extraction method. But now extractors of sufficient size can be constructed so as to give a reasonable capacity.

The finely ground raw material is suspended in the menstruum (solvent) in the extractor. High-frequency vibration is applied, and, in a very short time, the raw material is exhausted. Due to the better yield given by this method in comparison to ordinary extraction, the ultrasonic extracts are often cheaper in use than the old types of extracts.

This method is particularly useful for extraction of flavours from heat sensitive materials, such as coffee, spices, etc., but flowers and herbs are also treated by this method now, e.g., mimosa, thyme, etc.

This method has always made much sense to me but, although there have been several specialists for many years, the supply of ultrasonic extracts has been very limited. Perhaps that is about to change.

Finally.....
We have just received an Oxfordshire Green Bauble Award for our recycling efforts, which can’t be a bad start to the New Year!   






charles@essentiallyoils.com

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