For The Pacific Islands

The Practical Planter

Cassia: A New Spice Prospect

In coming months, PIM will publish articles supplied by the British Government's Tropical Products Institute on the various forms of the spice cassia. This month: Chinese cassia.

Chinese cassia, which is derived from the bark of the ■innamonutn cassia tree, has been cultivated in China since time nmemorial. The best of it comes from the Tung Ring district i southern Kwangsi, but there are extensive plantations around oting and Lukpo in Kwangtung, where good cassia is produced.

le cassia is grown on artificially iced hillsides at altitudes of from to 1,000 ft. The first cut of is obtained when the trees are it six years old. A few trees are uncut until 10 years old or more rovide the “buds” and seed; such may reach heights of up to t. The majority of the trees that used for bark production are n in plantations, and are usually agated from cuttings planted ig February, March or April— Jtimes, however, seed is used— seedlings are raised in nursery and, when one to two years planted out 2 ft apart, hen the trees are five to seven ; old and five to nine ft high, are cut down close to the ground a number of new shoots grow mm the stump and roots. The ts are harvested twice a year, main harvest in June-July and ler smaller one in January nary.

Ringed

oots which are 1 in. to li in. are cut a few inches above id level and stripped of their and leaves. They are ringed a large-bladed knife at intervals to 24 in. or else cut into pieces, tudinal slits are made and the is removed in two pieces by s of a curved horn spatula,

e bitter-tasting epidermis is

ved, either by scraping, or with all plane, and the bark dried in

the sun until it turns brown and curls into a hollow tube or quill. These are finally collected into bundles of about 18 in. diameter, and bound with rattans.

After passing through the hands of a number of intermediaries, the cassia reaches Hong Kong. Here the bundles are opened, and the cassia is immediately sorted into grades ac cording to thickness. The rolls, which are still semi-soft, are unrolled and both surfaces are cleaned of mud, insect fragments and dust with a stiff brush. Then they are washed in cold water, dried in the sun and tied into bundles of about 4 lb. each.

After fumigation for 12 hours, the bundles are packed into bales, usually of one picul (133£ lb.), in which form they are exported.

Main areas

The main cassia producing areas are situated on or near the mountainous border between Kwangsi and Kwangtung. Trees growing at the lower altitudes yield a relatively thick, coarse bark, somewhat deficient in flavour, containing 1.0 to 1.2 per cent, of volatile oil. This type of bark, the trade in which is centred on Lukpo, is sent to Canton, and forms the ordinary “cassia lignea” of commerce. Being brittle, much of it is broken in course of preparation for the market; it is, therefore, sold in three grades—whole quills, known as “China rolls” or “Canton rolls”,

“selected broken” and “extra selected broken”.

The better qualities are obtained from trees growing at high altitudes.

They are thinner, darker and of better flavour, having higher content of volatile oil (up to 215 per cent).

Three grades of whole quills, or “Kwangsi rolls”, are sold thin, medium and thick.

Finest

The finest cassias, which are much in demand in the US, are produced in the district of Tung King, in the extreme south of Kwangsi, near the Tonking border. These cassias are marketed as “Yunnan rolls”—thin, medium and thick—and as Yunnan broken cassia. One expert calculates that the volatile oil content of Yunnan cassia varies from 2.0 to 2.75 per cent, in the rolls and from 2.0 to 2.25 per cent, in the broken grade.

The refractive index of the oil varies from 1.58 to 1.602.

Cassia “buds” and seeds required for propagation are obtained from trees which have not been coppiced, but allowed to grow on for 10 years or more. The “buds” are not true buds but are the immature fruits together with the cup-shaped calyx into which the fruit is deeply set, and a short, slender stem.

When dried they are greyish-brown in colour, the fruit smooth and the calyx hard and wrinkled; they have a faint cinnamon-like odour, and a warm, sweet and pungent flavour.

Cassia buds are exported mainly to the US, Germany and Russia.

The twigs bearing the fruits are used by the Chinese as a remedy for fever, and the seeds are taken steeped in wine or eaten with betel-nut. The very thick bark obtained from such

hese trees as can be spared is not 3rted but is used in China, where is highly valued as a materia Uca. assia oil ; Distillation of this oil, main constituent of which is amic aldehyde, is a cottage istry. The distillation material, listing principally of the twigs leaves cut from the shoots used bark production, is usually stored 1 required, or dried and sold to ill-owner. It consists of about 70 cent. leaves and 30 per cent, s. he stills, which are set up on the ides close to streams from which r can be piped, are made locally consist of a cylindrical body of ;nt and wood or tinned metal, base being a shallow cast-iron ng-pan.

Slowly

ie still is charged with one picul 2 lb.) of leaves and twigs and 2\ s of water, and heated by means fire, using as fuel cassia wood which the bark has been re jd. Distillation is carried out ly to prevent the loss of vapours igh the loose fitting joints of the and condenser, and lasts three s or longer. ie mixture of oil and water ti collects on the underside of ondenser drains off into a trough ing round the inside of the head, which it is led away to the ator, the distillation waters being ned to the still and cohobated. e main trading centre for cassia s Wuchow, on the West River wangsi, close to the Kwangtung ;r. From here it is shipped down to Canton and Hong Kong, ssia oil exported from China is ally adulterated to a greater or extent with a mixture of rosin kerosene, sometimes with etic cinnamic aldehyde or a ire of this aldehyde and benzyl te. ur grades of a cassia oil are commonly exported from Hong ; the best quality, containing 95 per cent, of cinnamic alde contains very little adulterant; ower qualities, containing 85 to ;r cent, and 80 to 85 per cent, lehyde, are prepared from pure >y adding suitable quantities of ture of equal parts of cassia oil, and kerosene. The fourth quality fs of cassia oil of 80 to 85 per aldehyde content, to which "tic cinnamic aldehyde has been to bring the total up to 90 to r cent.