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Home , Absolute (perfumery), Concrete (perfumery), Essential oil, Rose oil, Rose water

-BEARING (Rosa damascena Mill.) CULTIVATION AND INDUSTRY IN TURKEY* (*published in Euro 14 (6):13-17, 2006)

Prof.Dr. Hasan BAYDAR Süleyman Demirel University, Rose and Rose Products Applied Research Center, 32260, Isparta-TURKEY http//gular.sdu.edu.tr e-mail: [email protected]

1. Introduction

The genus Rosa includes 200 species and more than 18000 cultivars (Gudin 2000). However, only a few of them exhibit the marked fragrance that is sought by perfumeries around the world (Antonelli et al. 1997). Rosa damascena Mill. (Damask rose, Oil-bearing rose, Pink rose) is the most important species, producing a high-value aromatic oil, which is used in the pharmaceutical, flavourings and fragrance industries (Lawrence 1991). The main producers of oil-bearing rose (Rosa damascena Mill.) in the world are Turkey, Bulgaria, Morocco, , Egypt, , China and India. Turkey and Bulgaria are the two largest rose oil and rose producers in the world. Approxiamately 1.5-2 tons rose oil and 3.5-4 tons rose concrete are produced anually in Turkey. Rose oil and rose concrete production in Bulgaria are estimated as 1-1.5 tons and 2.5-3 tons, respectively. The total world production of rose oil and rose concrete was estimated to be 15-20 tons. In Turkey, the famous ‘Turkish Rose Oil’ from Rosa damascena has been producing in large quantities for over 120 years. In addition to the rose oil and rose concrete, some important base materials of the cosmetic industry such as bioconcrete, , bioabsolute and are also obtained from the oil-bearing rose petals in Turkey. Today, exporting of rose oil, concrete, absolute, bioabsolute and rose water has important contrubution to the Turkish economy as a source for foreign exchange.

2. Oil-bearing Rose Species

It is generally accepted that there are many of rose species, yet only a few of them exhibit that marked fragrance that is sought by perfumeries in the world. The main rose species using in the production are oil-bearing rose (Rosa damascena Mill.), Apothecary's rose (Rosa gallica L.), Rose-de- mai (Rosa centifolia L.), White rose (R. alba L.), China rose (R. rugosa L.) and Musk rose (Rosa moschata Herrm.) (Guenther 1952, Lawrence 1991, Antonelli et al. 1997). In the world as well as Turkey, Rosa damascena Mill. (2n=28) is the main species for oil production. Rosa damascena supposed to be form a hybridization between R. gallica L. and R. phoenicia Boiss., both of which grow wild in Turkey (Baytop 1993). There is no any genetic variation among R. damascena grown in Turkey according to the results of RAPD, AFLP and microsatellite markers (Ağaoğlu et al. 2000, Göktürk Baydar et al. 2004). Therefore, it is necessary to create genetic variability especially for improving novel scent types of Rosa damascena thanks to the classical and biotechnological breeding methods. White rose (Rosa alba L.) is also grown in limited areas in Turkey. However much Rosa alba can grow in cold and unsuitable soils better than Rosa damascena, its oil content and oil quality are lower than pink rose. For this reason, white rose are sold at half the price than that of the pink rose. This state also explain why the interest towards this rose subsided.

3. History of oil-bearing Rose in Turkey

Anatolia is one the oldest places in which rose oil is well-known and well-used. For example, Hippocrates mentions that "Rosaceum Oleum" was prepared in Anatolia by macerating fresh in . There are some documents that the first oil-bearing rose (Rosa damascena) cultivation is began in Thrace region of Turkey. The first roses were brought to Thrace by the returning soldiers of Alexander of Macedon's garrisons. Belgian chronicle mentions that in 1210 crusaders saw large areas planted with

1 roses near Edirne which was the first capital of the Turkish Empire. It was also the largest commercial center for a long period of time. The French Ambassador to Edirne wrote in 1849 that rose oil was produced in the environments of Edirne. It is assumed that those chroniclers, who wrote about Edirne, often had in mind the Rose valley as well. Administratively (Bulgaria) belonged to Edirne province and was thus under the supervision of its chief gardener. The soil and the climate in the Kazanlak region turned out to be quite suitable for the rose, so the planting was sustained there, while in the surroundings of Edirne it declined and eventually disappeared. Reviewing in detail all that was written on the origin of the Bulgarian oil-bearing rose, Venelin Topalov presumes that the cultivation of roses was introduced to the region around Kazanlak, a town founded in 1420, by Turks (Anonymous 2005). Apart from the knowledge mentioned above, it is supposed that rose introduced into Isparta province of Turkey in 1880’s by a Turkish emigrant from Kazanlak. İsmail Efendi was the first person who accomplished to get first rose oil in the retorts in Isparta in 1892. After that, Göller region (Lakes region) of Turkey became extensively oil rose production center (Figure 1).

Figure 1. Lakes region: Rose valley of Turkey

4. Cultivation of oil-bearing Rose in Turkey

The best quality rose oil in accordance with the world standarts is produced from the rose flowers which are grown basically in Göller region’s provinces of Isparta, Burdur, Denizli and Afyonkarahisar for ornemental and commercial purposes. Espicially Isparta province (latitude 37o45’ N, longitude 30o33’E, altitude 997 m) is accepted as the valley of the oil rose in Turkey. The climatic conditions of Isparta proved to be favorable for the cultivation of the rose. The air humidity, cloudiness and precipitation in the flowering season (May and June) contributed to obtain roses with high yield and high quality. Rose cultivation in the rose valley of Turkey is not stable from year to year. Rose plantation areas fluctuate mainly due to price given for oil rose flowers. When prices are low, rose plantation sustituted by other more profitable agricultural crops. Today, total rose plantation area and total rose production of Turkey are about 1500 ha and 10000 tons, respectively. 80% of oil rose production of Turkey is from Isparta and 20% from Burdur, Afyonkarahisar and Denizli districts. Roses can be successfully grown on a wide range of soils but they do best on well-drained soils, with a soil pH of 6.0-6.5. The ground has to be well plowed prior to planting, usually in late summer. In early autumn, about 45 days prior to planting, rose growers start shoveling parallel ditches. The orientation of the land is mainly North-South, to allow maximum exposure to the sunlight. It is generally believed that the more sun the roses got, the more buds they produced and, respectively, higher crop was obtained. Fertilisers containing nitrogen, phosphorus, sulphur and potassium are needed for high flower production, and the chosen fertiliser dressing should relate to soil analysis. The plantations are started by making trenches 40-50 cm deep by about 40-50 cm broad at 2-3 m apart. After rose twigs or cuttings from old gardens cut at the soil level, they are placed into ditches horizontally, their ends overlapping in the trenches which are then covered with soil containing manure. The cuttings necessary for planting are procured from old rose fields, not younger than six years. 1 unit area of a cut-off garden provide material for planting of 3 unit area of new gardens, preserving the old one, so that in three years time it can bear blossoms again. The rose gardens planted in this way, with mutually protecting rows, remain productive for over 30 years. It is less labor consuming than other methods in which seedlings are used. A rose field normally yields 5 tons of fresh roses per ha after 3th

2 year. It is normally for a field to be productive for up to 40 years. Once in every 8 or 10 years, plants are cut to soil level to rejuvenate the field. Usually the vegetation of roses begins in March with the formation of the buds. The buds develop in April and usually start opening around May 15-20 (No flowers are produced in the establishment year), so the harvest begins at that time as well. Roses are gathered during the 40 day growing season after the first buds were to be seen in the gardens. Picking begins before the sun rises and stops around 10:30 a.m. The flowers are picked into sacks as early as possible each day on the basis of flower maturity. A flower is picked as it reaches full bloom and unopened buds are left for subsequent picking. The roses are pulled between the fingers so the entire blossom pops off into the hand. An experienced picker can harvest as much as 60 kilograms in a day. Depending on the intensity of the blossoming, the harvest begins at a slow pace, the amount of flowers gathered increasing with each day. Harvest lasts some 30-40 days, depending on the clamatic conditions. Towards the middle of the harvesting period, within a single peak day, as much as 8% of the entire crops of the season are gathered. After the peak day, the daily output gradually decreases.

5. Rose Oil Industry in Turkey

Blossomed flowers are hand picked during the early hours of the day by the farmers during the May and June months and then taken to the factory every morning for . The picked flowers should be chilled immediately to prevent heating, and distilled as soon as practical. In Turkey, rose oil is primarly two kind type; factory and village types. 1- Factory type oil is produced by water/ in tinned copper or stainless steel stills. 2- Village type oil is produced by water distillation in retorts. In the recent years, village type rose oil production in retorts has been very limited in Turkey. In place of this, the rose oil factories with fairly modern and supplied with new technologies have been established in order to produce rose oil and other products with higher yield and quality. There are about 15 rose factories in Turkey, some of them belong to private sector and 5 of them to Gülbirlik (Union of Cooperative Societies for Agriculture and sales of Rose Oil and Oily ). Gülbirlik was established in 1954 as the union of nine founder cooperatives. At present it consists of 6 cooperatives, 8.000 producing number 5 rose oil and concrete factories.

6. Distillation of oil-bearing rose

There are several methods of obtaining aromatic substances from rose petals. Distillation is the most widely used and the most economical method of extracting rose essential . In distillation, the rose flowers is heated in stills, either by placing it in water which is brought to the boil or by passing steam through it. The heat and steam cause the cell structure of the material to burst and break down, thus freeing the essential oils. The essential oil molocules and steam are carried along a pipe and chanelled through a cooling tank (condencer), where they return to the liquid form () and are collected in a special tank (Florentine). The emerging liquid is a mixture of oil and water, and since essential oils are not water soluble they can be easily seperated from the water and and siphoned off. Essential oils which are lighter than water will float on the surface in the florentine flask. The rose petals collected from gardens and packed tightly in sacks are laid out on the floor of the factory in order to allow slight decomposition, which aids in the development and improvement aromatic quality of the essential oil. The rose petals are loaded into the stills. 3000 liter stills made copper and steam jacketed are used for distillation. Coils inside the bottom of the still carry the steam which heats the water in the still. Distillation is generally done in copper stills, which had a capacity of 500 kg flowers and 1500 liter warm water. The distillation in the stills is carried out for 1.5 hours. During the hydrodistillation of rose flowers, essential oils are liberated from the structures where they are stored in the petals by diffusion. While distilling, the condenser temperature is held at 35-45°C to prevent deposition of the in the condenser, and at a specific gravity of about 0.85 the oil constituents sit on the water surface. Unfortunately, however, owing to the loss of phenyl-ethyl , a large proportion of which remains dissolved in the distillation water, the otto does not accurately represent the flower odour. The distillate is collected in 200 liter florentine flasks of the copper stills. The oil that seperates out in the florentine flasks is called decanted oil, first oil or direct oil. The bottom water and decanted oil in the florentine flasks are then pumped into the stainless steel tanks to get the redistilled oil called water oil, second oil or indirect oil. Later, the first and second rose oils are blended to get the final product sold in the markets.

3 The compositions of the first and second oils are fairly different. The contents of such as , gerniol, and are higher in the second oil according to the first oil (Baydar and Göktürk Baydar 2001). Due to the quality differences, first and second oils must be blended in a certain ratio after GC analyses to obtain the final incredible and precious rose oil – rose otto. The distillate after removal of the oil is also sold as rose water. Consequetly, rose water is a by-product obtained during the hydro-distillation of rose flowers to produce rose oil. Rose water contains very little rose oil. The main essential oil compounds of rose water is phenyl-ethyl alcohol (Göktürk Baydar and Baydar 2005). The rose petals generally contain very little essantial oil in comparation with other essantial oil plants. Generally, 1 kg rose oil can be obtained from 3000-4000 kg of rose petals. So, the rose oil yield is about 0.03-0.04%. For this reason, rose oil is one of the most expensive essential oil sold in the world markets, partly due due to lack of natural and synthetic substitutes. extraction yields about 10 times that obtained by water distillation,1 kg rose concrete can be obtained from 375-400 kg rose petals. The monetary value of 1 kg rose oil was between 5750 and 6000 US $ and of 1 kg rose concrete was between 600 and 650 US $ in 2005. Rose oil is produced by water distillation of fresh rose flowers. Some physical and chemical characteristics of Turkish rose oil are presented in Table 1. Rose oil is a very complicated mixture of more than 100 different components. Monoterpene alcohols such as linalool, citronellol, nerol and , hydrocarbons such as , 1-nonadecene, heneicosane, , tricosane and octadecene, hydrocarbons such as α-guaiene, , λ-muurolene and δ-guaiene, oxides and such as methyl , and such as geranyl acetate and geranial, phenols such as eugenol are among of the most important rosaceous characters found in the Turkish rose oil (Anaç 1984, Kürkçüoglu 1988, Başer 1992, Bayrak and Akgül 1994). The rose oil is mainly characterized by having high percentage of the monoterpene alcohols including citronellol, geraniol, nerol, linalool and phenyl-ethyl alcohol. Phenyl-ethyl alcohol is a major oil component, but because of its solubility in water it is usually lost in the distillation waters unless collected as rose water. Many other components in rose oil are present only in trace amounts but are also very important for the overall quality. These components contribute mainly to the perfumery value of rose oil. Low contens of the hydrocarbones which cause the solidification when the oil is chilled and high contents of monoterpene alchols which cause rosaceous and freshness character are desired to get high rose oil quality. The oils from late and late pickings give more percentages of the monoterpene alchol compenents and less percentages of the steoroptene hydrocarbones (Başer 1992). Citronellol is the major component which determines the rose oil quality. As the sum percentages of citronellol, nerol, and geraniol which are the basic alcholic components of the rose oil change from 45 to 72%. Citronellol/geraniol (C/G) ratios, which are used for evaluating of the quality of the rose oil, change between 1.10 and 3.91 (Lawrance 1991). Methyl eugenol is not desired above a particular concentrations in rose oil due to the its possible negative side and allergic effects on human healt. Methyl eugenol levels may be over 2.5%, especially in the oils distilled from excess or long-term fermented flowers. In the recent years, ‘Super Critical Carbon Dioxide Extraction’ has been introduced for the industry. Oils which are extracted utilising carbon dioxide are supposed to be superior, pure and very close to the natural essential oil as it exists in the plant – and they are completely free of residues of carbon dioxide. But, this new method is under discussion in the rose oil production. Perhaps, ‘Hydrodiffusion/Percolation’ will be the most modern method of rose extraction. This procces is faster then distillation, and the equipment is much more simple then taht used for carbon dioxide extraction. Steam spray is passed through the plant material (which is suspended on a grind) from above. The emerging liquid composed of oil and condensed steam is then cooled. The result is a mixture of essential oil and waste (as in the distillation process) which can be easily seperated.

4 Table 1. Some main physical and chemial characteristics of Turkish rose oil

Characteristics Turkish rose oil Odour description Floral, strong and sweet rosaceous character Appearance Liquid at 25ºC (fluid, transparent liquid above congealing point) Colour Yellow to yellow-green Specific gravity (25 oC) 0.844-0.868 Refractive index (25 oC) 1.452 - 1.463 Optical rotation (25 oC) -3.3 to -5.9 Freezing point 16.5 to 23.0 ºC Acid number 2.75 (max. 3.75) number 15.1 Ester number ffter acetylation 223.6 Explosion limits lower 88ºC, upper 122ºC Autoignition temperature 460ºC Purity 100 % Natural Citronellol (35.1%), geraniol (17.9%), nonadecane/1-nonadecene (10.2%), nerol (8.4%), heneicosane (3.9%), phenyl-ethyl alcohol (2.5%), methyl eugenol (2.3%), (2.1%), eugenol (1.6%), heptadecane (1.4%), alfa- pinene (1.2%), geranyl acetate (1.1%), linalool (1.0%), and others such as Composition farnezole, terpinene-1-ol-4, acetates of the indicated alcohols such as citronelyl acetate, neryl acetate, linalyl acetate, etc., free acids, aldehydes fatty and aromatic, geranial, neral, ketones, phenols and phenol esters, hydrocarbons, rose oxide and steroptene. Intended Use Perfumery, cosmetics and pharmacy

7. Solvent extraction of oil-bearing rose

The process of solvent extraction does not yield essential oils. This method is employed for flowers, gums and and it produces ‘concretes’, absolutes’ and ‘resinoids’. To yield a concrete and an absolute, the aromatic plant material (flowers, , etc.) is extracted by hydrocarbon such as , petroleum , . The plant material is covered with the solvent and slowly heated to dissolve the aromatic molecules. The solvent the odour and then the solvent is avoparated in vacuum to produce concrete which is a semisolid, -like substance. To obtain the absolute the concrete is mixed with pure alcohol to dissolve out the aromatic molecules, and then chilled. This mixture is filtered to eliminate waste products and to seperate out insoluble waxes. The alcohol is evaporated off under vacuum. The thick, viscous, coloured liquid known as the absolute is left behind. Rose concrete is a waxy product obtained by extraction of fresh rose flowers with volatile solvents such as n-hexane and petroleum ether in the extractor (rotary or static type). Industrial poduction of rose concrete in rotary extractor is as follows: about 500 kg of rose flowers are charged into 3000 L extraction vessels equipped with mixer. The vessel is filled with n-hexane up to halfway mark (about 1500 L) and the first extraction takes place for 20 min at 60-65 oC (Colin 2003). After pumping of the extract to into a tank, second extraction in the same vessel is repeated with a second charge of about 1000 L n-hexane for 15 min. The third extraction can also be done with 500 L n-hexane for 10 min. At the end of the all extraction, overall extract collected with the tank is pumped into a evaparator which evaporates n-hexane in vacuum at 60-65 oC. Rose concrete is a semisolid mass with a waxy look, and it represents the true fragrance of rose flowers (Kürkçüoğlu and Başer 2003). The highest essential oil component in concrete is phenyl-ethyl alcohol over 50%. Its citronellol, geraniol and nerol contents are lower, but phenyl-ethyl alcohol content is higher than rose oil (Göktürk Baydar and Baydar 2005). Bioconcrete, a product obtained from the flower residue after hydro-disitllation with a solvent extraction (n-hexane, petroleum ether, etc.) has an essential oil composition different from concrete. The most abundant essential oil components in bioconcrete are nonadecane, heneicosane and phenyl-ethyl alcohol (Göktürk Baydar and Baydar 2005). Rose absolute is a product obtained from the concrete with ethyl alcohol extraction. In the extractin of 1 kg concrete to produce over 500 g absolute, 8-10 L ethyl alcohol is used (Colin 2003). The alcohol dissolves and absorbs the fragrant material from the concrete. Waxes, and other non-aromatic contents precipitate out and are removed by filtering at -15/-20 oC. Removal of alcohol through

5 evaporation in vacuum yields rose absolute which is a reddish liquid with a typical rose odour. Essential oil yield is higher in absolute than concrete. Rose absolute yields 20-25% essential oil. But its essential oil composition are different from rose oil and also concrete. The phenyl-ethyl alcohol content of its volatile portion is over 60% (Göktürk Baydar and Baydar 2005). Bioabsolute, a product obtained from the bioconcrete with ethyl alcohol extraction, has different composition according to the other rose products. The main components in bioabsolute are phenylethyl alcohol, heneicosane and nonadecane.

8. The factors on rose oil yield and quality

Essential oil content and quality of the rose petals are open to the various factors including genotypes, growing location, soil type and texture, air humidity and cloudiness during the season, agronomic practices (such us fertilization, irrigation, harvesting), fermentation duration of petals and distillation proccesses (Weiss 1997). The essential oil content of the rose petals collected in cool season is higher than that of the petals collected in warmer season. It has been known that the increases in the temperatures cause to remove the essential oils from the trichomes of the petals (Weiss 1997). In a study, rose oil content was 0.04% in May and 0.03% in June (Baydar and Göktürk Baydar 2005). It is neccassary to pick up the roses as quickly as possible in the earlier hours of the day in order to produce more essential oil. For example, although the rosses picked at 5 a.m. contained essential oil as high as 0.060%, that of roses picked at 17 p.m. contained only 0.014% in the Clavenger apparatus (Kazaz 1997). It was also necessary to make the distillation after harvesting as quickly as possible in order to produce more essential oil. In practice, only fresh flowers should be preferred for factory type oil distillation. However, due to the large quantities of flowers in the factory, the flowers undergo varying degrees of fermentation until distillation (Başer 1992). Sometimes the rose petals are extremely fermented because of the waiting (Bayrak and Akgül 1994). For example, fermentation for 36 h duration decreased the oil yield from 0.035 to 0.025% (Baydar and Göktürk Baydar 2005). This small difference is very important for economy of industrial rose oil production. The fermentation not only reduces the oil content, but also increases the citronellol content in opposition to the content of geraniol. For example, the fermentation of rose flowers for 36 h duration at 25 oC in sacks decreased citronellol content from 25.3 to 67.9% and decreased geraniol content from 44.7 to 6.7% (Baydar and Göktürk Baydar 2005). It is generally preferred that the citronellol content should be found in a desired percentages (30-40%) in the rose oil. As a result, it could be recommented the rose petals harvested from the early hours of the day and early picking periods of the flowering season, and also distilled without waiting (non- fermented or short-term fermented) after harvesting for high oil yield and quality. Furthermore, the oil content may be increased by tween 20 treatments without changing the oil composition. This result is mainly due to the fact that tween 20 reduce the surface tension between oil bearing trichomes on the petals and the distillation water (Baydar and Göktürk Baydar 2005). It could be concluded that distillation time can be limited for higher contents of citronellol and geraniol contents and less contents of methyl eugenol and hydrocarbones in the rose oil at the expense of a little oil loss.

9. References

Ağaoğlu, Y.S., Ergül, A., and Baydar, N., 2000. Moleculer analyses of genetic diversity oil rose (Rosa damascena Mill.) grown Isparta (Turkey) region. Biotechnol.&Biotechnol. Eq. 14: 16-18. Anaç, O., 1984. Gas chromatographic analysis on Turkish rose oil, absulute and cocrete. Perfumer & Flavorist 9:1-14. Anonymous, 2005. The Bulgarian Rose Co. /www.bulgarskarosa.com/ Antonelli, A., Fabbri, C., Giorgioni, M.E., Bazzocchi, R., 1997. Characterisation of 24 old from their volatile compositions. J. Agric. Food Chem. 45, 4435 Başer, K.H.C., 1992. Turkish rose oil. Perfumer & Flavorist 17: 45-52. Baydar, H., Baydar Göktürk, N., 2005. The effects of harvest date, fermentation duration and Tween 20 treatment on essential oil content and composition of industrial oil rose (Rosa damascena Mill.). Industrial Crops and Products 21: 251-255

6 Baydar, H., Göktürk Baydar, N., 2001. The effects of harvest period, waiting time for distillation and distillation phases on yield and quality of oil-rose (Rosa damascena Mill.). IV. National Field Crops Congress, 17-21 September 2001, pages 117-122, Tekirdağ, Turkey. Bayrak, A., Akgül, A., 1994. Volatile oil composition of Turkish rose (Rosa damascena). J. Sci. Food Agric. 64: 441-448. Baytop, T., 1993. The cultivation of oil-rose and the production of rose oil in Anatolia during the Ottoman era. In: Essantial Oils for Perfumery and Flovours, eds Başer, K.H.C., Giller N., AREP Pub. Istanbul, Turkey. Colin, H.A., 2003. Extraction and Idustrial Processes. In: Encyclopedia of Rose Science. Elsevier Ltd. Academic Press. p 726-735. Göktürk Baydar, N., Baydar, H., Debener, T., 2004. Analysis of genetic relationships among Rosa damascena plants grown in Turkey by using AFLP and microsatellite markers. Journal of Biotechnology 111: 263-267. Göktürk Baydar, N., Baydar, H., 2005. Essential oil compositions of Turkish oil rose (Rosa damascena Mill.) products. 36th International Symposium on Essential Oils, 5-7 September 2005, Budapest- Hungary. Gudin, S., 2000. Rose: genetics and breeding. Plant Breed. Rev. 17, 159-189. Guenther, E. 1952: Oil of rose. In: The essential oils. Vol 5. Kreiger, Florida, USA. pp. 3-48. Kazaz, S., 1997. Hasat zamanı ve hasat sonrası bekleme süresinin yag gülünde (Rosa damascena Mill.) yağ miktarı ve kalitesine etkileri üzerine bir araştırma. MS thesis in Süleyman Demirel University, Isparta, Turkey. Kürkçüoglu, M., 1988. Production and analysis of Turkish rose oil. MS thesis in Anadolu University, Eskişehir, Turkey. Kürkçüoğlu, M., Başer, K.H., 2003. Studies on Turkish rose concrete, absolute, and hydrosol. Chem. Natur. Comp. 39 (5): 457-464. Lawrence, B.M., 1991.Progress in essantial oils: Rose oil and extracts. Perfumer & Flavorist 16: 43-77. Weiss, E.A., 1997. Essential Oil Crops. CAB International, New York, USA.

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