Cinnamon - Production of quills, uses in the food industry

Cinnamon

1 Introduction

The name cinnamon refers to the tropical evergreen tree as well as the bark that is extracted from the plant. Cinnamon is known as cannelle in French; ceylonzeimt/kaneel in German; cannella in Italian; canela in Spanish, yook gway in Chinese, dal-chini in Hindi and kurunda in Sinhalese. Cinnamon spice is obtained by drying the central part of the bark and is marketed as quills or powder. The production of cinnamon is mostly limited to the wettest lowland areas of Southeast Asia. Cinnamon is cultivated up to an altitude of 500 metres above mean sea level where the mean temperature is 27sC and annual rainfall is 20002400 mm. It prefers sandy soil enriched with organic matter. Cinnamon is classified in the botanical division Magnoliophyta, class Magnoliopsida, order Magnoliales and family Lauraceae. The tree grows to a height of 7 to 10 m in its wild state and has deeply veined ovate leaves that are dark green on top and lighter green underneath. Both bark and leaves are aromatic. It has small yellowish-white flowers with a disagreeable odour and bears dark purple berries.

The genus Cinnamomum has 250 species and many of them are aromatic and flavouring. In many instances, very little distinction is made between the bark of Cinnamomum verum (syn. C. zeylanicum, true cinnamon) and Cinnamomum cassia

(Chinese cinnamon). C. verum provides cinnamon bark of the finest quality and oil of cinnamon whereas C. cassia provides cassia bark and oil of cassia (also known as oil of cinnamon). Cassia was used in China long before the introduction of true cinnamon but is now considered an inferior substitute. There are still other species of Cinnamomum which are often traded as cinnamon or cassia.

Cinnamon as a spice dates back in Chinese writings to 4000 BC. The botanical name Cinnamomum is derived from the Hebraic and Arabic term amomon, meaning fragrant spice plant. Cinnamon is referred to in the Old Testament and in Sanskrit writings. In ancient Egypt, cinnamon was used medicinally, as a flavouring and in embalming. The spice was highly prized by the Greeks and Romans. It was one of the spices which sent Columbus west to discover the eastern Spice Islands. It was the same search for spices that led Vasco da Gama to round the Cape of Good Hope and reach the Malabar Coast of

India in 1498. The Portuguese invaded Sri Lanka immediately after reaching India in

1536 mainly for cinnamon. Both Herodotus in the fifth century BC and Theophrastus in the fourth century BC

believed that cinnamon and cassia came from the neighbourhood of Arabia. Cinnamomum zeylanicum, is reported to have originated in Sri Lanka and the Malabar coast of India.¹ C. cassia is reported to have originated in South-East China. Other economic species of Cinnamon, which are commonly used as substitute for cinnamon/ cassia, are detailed in Table 1.

A lot of confusion exists between cinnamon and cassia. While cinnamon and cassia are not precisely the same, they are closely related and the bark of the two is not all that different. It may be a surprise to many to know that what is sold in American stores as cinnamon is mostly cassia. Cassia is thick, hard and has a flavour that is extremely bitter and burning with somewhat of a bite in the after taste. Cassia has a double curl when it dries, meaning that this is a spiral of dried bark, a small bit of relatively straight bark, then the other long edge spiral in the opposite direction. Ground cassia has very reddish brown colour. True cinnamon has but a single spiral curl and is almost papery, brittle, easily crushed or powdered. Its flavour is more subdued, less bitter and has a decidedly sweet finish in the after taste. Its smell is sweet and aromatic. The bark of cinnamon is pale yellowish brown.

2 Chemical structure

Cinnamon bark contains:

 moisture 9.9%

 protein 4.65%

 fat (ether extract) 2.2%

 fibre 20.3%

 carbohydrates 59.55%

 total ash 3.55%

 calcium 1.6%

 phosphorus 0.05%

 iron 0.004%

 sodium 0.01%

 potassium 0.4%

 vitamins (mg/100g) B1 0.14; B2 0.21; C 39.8; niacin 1.9; A 175 I.U.

It has a caloric value (food energy) of 355/100 g.² It also contains up to 4% volatile oil, tannins constituting of polymeric 5,7,3 ,4 -tetrahydroxy flavan-3,4diol units catechins and pre-anthocyanidins, resins, mucilage, gum, sugars, calcium oxalate, two insecticidal compounds (cinnezalin and cinnzelanol); coumarins and others.³ The sweet taste of cinnamon is due to the presence of cinnamaldehyde. It is reported that, when combined with sweet food, the sweet sensation of the food is enhanced because of the synergetic effect between the sweet taste of sugar and sweet aroma of cinnamon.⁴ Sweetish bark with pungent taste and low mucilage (about 3%) is preferred by the food industry. The deodouring/masking property of cinnamon bark is due to the presence of trimethyl amine. The bark oil consists of cinnamaldehyde (8090%), eugenol, eugenol acetate, cinnamyl acetate, cinnamyl alcohol, methyl eugenol, benzaldehyde, cinnamaldehyde, benzyl benzoate, linalool, monoterpene, hydrocarbon, caryophyllene, safrole and others

Table 1 Major economic species of Cinnamomum

Botanical name Common name Origin/centre of Part used Major use

production

Cinnamomum verum Presl. Syn True cinnamon/Ceylon cinnamon Sri Lanka, Malabar bark, leaves Flavouring, perfumery,

C. zeylanicum Blume Coast, Seychelles medicinal

C. cassia Presl. Cassia, Chinese cinnamon Southeast China bark, leaves, buds Flavouring, medicinal, Chewing pan

C. camphora Camphor Southern China/ Wood/ leaves Medicinal/perfumery

Indonesia

C. loureirii Nees Saigon cinnamon, Vietnam cassia Vietnam bark, bark oil Flavouring

C. burmanii Blume Cassia vera, Korinjii cassia Indonesia bark (Massoi bark) Spice and oleoresin in flavouring

C. tamala Indian cassia India bark, leaves Medicinal, leaves as bay leaves for flavouring

C. ineris Wild cinnamon of Japan Japan, Southern bark Mosquito repellent

India

C. sintok Java cassia Java and Sumatra bark Flavouring

C. obtusifolium Northeast India, bark Substitute for true cinnamon

Myanmar

C. culilawan and C. rubrum Moluccas and bark, bud Flavouring, substitute for

Amboyana clove bud C. olivera Australian cinnamon Australia bark Flavouring C. glaucascens Sugandha kokila Nepal bark/leaves Perfumery

such as pinene, phyllandrene, cymene and cineol.⁵ Bark oil is a pale yellow to dark yellow liquid with a strong, warm, sweet, spicy, tenacious odour and a sweet, pungent but not bitter taste.

The root bark oil consists of camphor at 60%. It is colourless to pale yellowish brown, similar in odour to stem bark oil but weaker, lacking in fragrance and camphoraceous odour. The leaf oil is a yellow to brownish yellow, with a warm, spicy, somewhat harsh odour, lacking the richness of bark oil. Cinnamon leaf oil has eugenol (8088%), cinnamaldehyde, cinnamyl acetate, pinene, linalool, eugenol acetate and some minor compounds. The iso-eugenol produced from eugenol fractionated from cinnamon leaf oil possesses more desirable aroma and flavour than that derived from clove leaf oil.⁶

Chip oil has a very good odour and flavour although contains 20% less cinnamaldehyde and twice the amount of eugenol. Seeds contain 33% fixed oil used for making candles. This oil is also called cinnamon suet. Oleoresin is a deep reddish or greenish brown, rather viscous liquid.

Cassia bark yields from 12% volatile oil, resembling that of cinnamon. Its value depends on the percentage of cinnamaldehyde. The oil also contains cinnamyl acetate, cinnamic acid, phenyl propyl acetate, orthocumaric aldehyde, tannic acid and starch.

3 Production

Sri Lanka followed by the Seychelles and Malagasy Republic are the major producers of true cinnamon bark with the best quality, while Indonesia, China and Vietnam contribute the major share of cassia. India, Malaysia, Indian Ocean Islands and West Union territories are occasional exporters but their impact on world trade is not so significant. The major use of cinnamon is in the form of ground cassia and it comes from Indonesia.⁷

The low grade cinnamon comprising feathering and chips is produced in limited quantities in Sri Lanka but constitutes a much larger share of total exports from Madagascar. The major importer of cinnamon is Mexico followed by West Germany, USA and Great Britain. Other importers are Saudi Arabia, Taiwan, Singapore, Hong Kong and France.⁸ Spice is traded internationally in whole form and grinding is often carried out in the consuming centres.

Bark oil is produced from the distillation of imported cinnamon/cassia in Western Europe and North America. The major cinnamon bark oil supplier is Sri Lanka, and France is the biggest importer followed by USA.⁹ Leaf oil is distilled in Sri Lanka and the Seychelles. USA and Western Europe are the largest markets for cinnamon leaf oil. The ready availability of eugenol ex clove leaf oil has led to some loss in market for cinnamon leaf oil. The major producer of cassia oil is China. USA and Japan are its major importers. Small quantities of cassia oil are produced in Indonesia, Vietnam, India and Nepal but these are obtained from species of cinnamon other than C. cassia and are much less widely traded than Chinese oil.

Harvesting for bark is made after the second or third year of planting and the subsequent harvest is made between 12 and 18 months after the previous harvest. Quills of 60125 kg/ha are obtained from the first harvest. Plants with an age of 1012 years will give about 225300 kg quills per hectare. Cutting of the tree is normally done in the wet season from central portions of shoots. The finest quality of bark is obtained from shoots with uniform brown colour, thin bark 1.01.25 m length and 1.25 cm diameter. The ideal time for cutting the stem is when the red flush of the young leaves turn to green and this is the indication of the free flow of sap between the bark and the wood. Shoots

ready for peeling are removed from the stumps and the terminal ends of shoots are also removed. The harvesting season varies from May to November, although harvesting on a limited scale continues throughout the year.

3.1 Production of quills

There are a number of stages in the production of quills²

 Peeling: the rough outer bark is first scraped off with a special knife. Then the scraped portion is polished with a brass rod to facilitate easy peeling. A longitudinal slit is made from one end to other and the bark is peeled off. A shoot cut in the morning is peeled on the same day.

 Rolling: The barks are packed together and placed one above the other and pressed well. The bark slips are reduced to 20 cm length and are piled up in small enclosures made by sticks. Then they are covered with dry leaves or mat to preserve the moisture for the next days operation and also to enhance slight fermentation. The retention of moisture is important for the next operation: piping.

 Piping: Rolled slips are taken to the piping yard for piping operations. The outer skin is scraped off with a small curved knife. The scraped slips are sorted into different grades according to thickness. The graded slips are trimmed, ends are cut and pressed over pipes. Slips are rolled into pipes and soon after, they are allowed to dry. During drying, smaller quills are inserted into the bigger ones, forming smooth and pale brown compound quills, which are known as pipes. The quills are arranged in parallel lines in the shade for drying as direct exposure to the sun at this stage would result in warping. The dried quills, thus obtained, consist of a mixture of coarse and fine types and are yellowish brown in colour. The quills are bleached, if necessary, by sulphur treatment for about 8 hours.

The process of producing quills has several by-products which are used in further processing:

 Quillings: These are broken pieces of quills used mainly for grinding but also for distillation of oil. The pieces vary considerably in size, being about 5 to 15 or 20 cm in length and about 10 to 25 mm in diameter.

 Featherings: These are short shavings and small pieces of left overs in the processing of the inner bark into quills. Collectively, featherings present a shade darker colour than the quills and a shade lighter than the chips.

 Chips: These are small pieces of bark, greyish brown on the outside and a lighter brown on the inside. They are deficient in both aroma and taste and are not to be compared to the quills for flavour.

3.2 Production of ground cinnamon

The heat of grinding is very destructive to the volatile oil content of cinnamon. Cryogenic grinding, however, does retain more volatiles and it is very good in the case of cinnamon.¹⁰

3.3 Production of oils and oleoresins

Distillation of chips and variable amounts of featherings and quillings through hydrodistillation or steam distillation produce cinnamon bark oil. Bark to be distilled

for oil should not be left in wet bundles or become damp, as this encourages mould or fermentation which directly affects oil composition. Cinnamon bark produces two oils, viz. a superior type derived from the inner bark, and a lower quality from broken quills, chips and bark. The leaves left after trimming the cut stems as well as those obtained from pruning operations provide the raw material for production of cinnamon leaf oil. About one tonne of leaves are obtained from one hectare which on steam distillation yields 2.53 kg leaf oil rich in eugenol. Cinnamon and cassia oils are both normally rectified to provide oil with a more uniform composition. Rectification is also required to produce feedstock eugenol for subsequent derivative manufacture.

Cinnamon oleoresin is also produced, to a lesser extent especially in North America, from cheaper Indonesian cassia for flavouring purposes. Oleoresin is prepared by extracting cinnamon bark with organic solvents, the yield using ethanol is 1012% and using benzene is 2.54.3%. Recently 1,1,2-trichloro-1,2,2trifluroethane has also been used.

3.4 Storage

Cinnamon should be stored in a cool, dry place. Excessive heat will volatilise and dissipate its aromatic essential oils, and high humidity will tend to cake it. Date the containers when they arrive, so that older stock will be used first. Store them off the floor and away from outside walls to minimise the chance of dampness. Make it a hard and fast rule that all spice containers be tightly closed after each use, because prolonged exposure to the air will also cause some loss of flavour and aroma. Under good storage conditions, the qualities of aroma and flavour for which cinnamon is prized will be retained long enough to meet any normal requirements of commercial baking. Whole cinnamon does not lose its volatile oil as fast as that of the ground form. When ground cinnamon is stored in bulk in an ambient warehouse, a good rule of thumb is loss of 0.1% volatile oil per month. Whole quills will keep their flavour longer. Oleoresin flavour is stable at high temperature. On prolonged storage, owing to oxidation, it becomes contaminated with resin and cinnamic acid and changes to cherry red.

4 Main uses in the food industry

A large proportion of the total usage of cinnamon is for culinary purposes. It can be bought as whole sticks, used to flavour rice and meat dishes, but recipes can also call for ground cinnamon. Cinnamon being more delicate is mostly used in dessert dishes. Hot apple cider just does not taste the same without a cinnamon stick. It is used to spice mulled wines, creams and syrups in Europe. In Mexico, the largest importer of Sri Lankan cinnamon, it is drunk with coffee and chocolate or brewed as a tea. Although in Western cuisine, it is mainly used in sweet dishes, its primary use is within savoury dishes in the East. In Indian cuisine, it is used in curries and pilaus and is an important ingredient in garam masala. Cinnamon sticks are used in beverages, boiled beef, pickles, chutneys and ketchup. It is common in many Middle Eastern, North African dishes in flavouring lamp tagines or stuffed aubergines. Cinnamon does more than add flavour to cakes, cookies, ice creams and other high fat desserts.

In India, Southeast Asia, USA and in European countries, cinnamon is used for flavouring foods. It is commonly used for de-odouring/masking in the food industry in the USA. Bark oil is employed mainly in the flavouring industry where it is used in meat and fast food seasonings, sauces and pickles, baked goods, confectionery, cola-type

drinks, tobacco flavours and in dental and pharmaceutical preparations. The bark oil is anti-fungal and anti-bacterial, slowing meat spoilage, so its use as a spice for meat dishes in warmer climates is sensible. Cinnamon oleoresin is used in flavouring, cake and similar mixes, pickles, prepared meats, convenience foods and related products. Leaf oil is used as a flavouring agent for seasonings and savoury snacks to a small extent. The iso- eugenol, derived from ex-eugenol cinnamon leaf oil, is another flavouring agent in confectionery and liqueurs.

The stronger flavour of cassia is preferred in chocolate manufacture by Germans and Italians and is used less frequently in the kitchen. Cassia oil is used mainly for flavouring cola-type drinks, with smaller amounts used in bakery products, sauces, confectionery and liqueurs. Dried unripe fruit, or Chinese cassia buds, have the odour and taste of the bark, and are rather like small cloves in appearance. They are employed in confectionery and in making pot-pourri. Cinnamon buds are as good for flavouring and spicing as the bark itself.¹¹

Cinnamon is used widely in baking both for colouring and flavouring. When purchasing cinnamon, however, the commercial baker must consider his specific needs. For certain purposes, it may be desirable to give a baked product high cinnamon colouring and yet only relatively mild cinnamon flavouring. In this case, the buyer would look for a red-coloured cinnamon (cassia) with a moderate oil content, or perhaps a cinnamon blend (in which two or more grades are mixed to give a desired performance). The blending of different cinnamon varieties or grades to create tailor-made cinnamon for various types of baked goods has become a standard practice. It is something which commercial bakers have requested and provided the blends are formulated properly, they have many advantages.

5 Functional properties and toxicity

This herb has been used medicinally for thousands of years to fight toothache, clear up urinary tract infections and soothe stomach irritation. It has a broad range of historical uses in different cultures including the treatment of diarrhoea, arthritis and various menstrual disorders. The large number of medicinal applications for cinnamon indicates the widespread appreciation of folk herbalists for its healing properties.

In the Indian System of Ayurvedic medicine, it is used against a wide spectrum of diseases like bronchitis, colds, congestion, diarrhoea, dysentry, oedema, flu, gas, metabolic and heart strengthening, hiccups, indigestion, liver problems, menorrhagia, melancholy, muscle tension, nausea and vomiting. It assists uterine contractions during labour and menstrual pain from low metabolic function. For external applications, it is used against headaches and pain.¹²