Essential oil extraction from roses
Additionally, with the upcoming of the WTO regulations since 2005, the competition for the export of major crops and their products is likely to grow and very high standards will be demanded for exportable commodities. It is time to develop and explore new means to ensure subsistence of our farmers and boost exports.
The introduction of rose essential oil through horticulture crop seems to offer local small farmers increased farm incomes. The value-added products from roses are unique and are likely to face less competition in the international market and thus have the potential for export and import substitution.
These products also give premium prices almost round the year and there is no need to wait for a long time as in the case of other routine crops. Net profit against the investment is appreciably higher as compared to the conventional crops.
Rose products (rose water, gulqand, oil) are in high demand all over the world. There are many rose species, however, only a few exhibit the marked fragrance that is sought by the perfumeries around the world. Rosa damascena mill. (damask rose, oil-bearing rose, pink rose), Rosa gallica and Rosa centifolia are the most important species, producing high-value aromatic oil, which is used in the pharmaceutical, flavourings and fragrance industries. Rosa centifolia enjoys heat, water, and high fertility, and under these conditions it flowers well and can be successfully grown on a wide range of soils but they do best on well-drained soils, with a soil pH of 6.5-7.5.
Adequate water is essential throughout the vegetative and flowering periods, and where irrigation is needed, basal watering, such as drippers, are favoured as they avoid wetting the flowers at harvest time. The frequency of watering depends on the porosity of soil and seasonal weather conditions. Roses are gross feeders and enjoy high fertility conditions.
Fertilizers containing nitrogen, phosphorus, sulfur and potassium are needed for high flower production, and the chosen fertilizer dressing should relate to soil analysis. In the establishment year, a multi-analysis fertilizer is a suitable dressing at rates of up to 500kg/ha. 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 and flowers are left for subsequent picking. The number of flowers ready for picking each day and the total weight of flowers harvested is variable and reflects the daily climatic conditions of the season.
Under Faisalabad climatic conditions Rosa centifolia produced marvellous flowering throughout the year. On an average, a single plant produces 1000g of flowers per year. This character of Rosa centifolia makes it distinguishable from all roses and grower can earn more by adopting this as a crop.
The rose essential oil can be extracted by using solvent extraction method (Hexane), stream distillation and high-pressure CO2 techniques. The fragrance of the rose flower, captured by extraction, is one of the most valuable flavour and fragrance products used.
The most common aroma concentrates of rose are rose oil and rose water, derived from hydro/ steam distillation; and rose concrete and rose absolute from solvent extraction. Different constituents of essential oil of roses were determined by using gas chromatography.
In the Rose essential oil extracted through solvent (hexane), 13 components were characterized. The components identified through gas chromatography in rose essential oil are Citronellol (54.745 per cent), Methyl Eugenol (3.901 per cent), Geraniol (2.684 per cent), Geranyl Acetate (2.524 per cent), Phenyl Ethyl Alcohol (30.691 per cent), Linalool (1.687 per cent), Benzaldehyde (1.156 per cent), Benzyl Alcohol (0.085 per cent), Rhodinyl Acetate (1.951 per cent), Citronellyl Acetate (0.789 per cent), Benzyl Acetate (0.245 per cent) and Phenyl Ethyl Formate (0.879 per cent).
At present rose oil is used in pharmaceutical preparations (e.g., ointments and lotions), beverages, sweets, cosmetics, food products and extensively used as a fragrance ingredient in perfumes, creams, and soaps. The increasing demands to meet requirements of the local industry are fulfilled through imports by spending foreign exchange.
As most species of rose grow and flower well under our conditions, Pakistan has the potential to grow roses for essential oil. The production of essential oil from rose is a relatively new type of agricultural activity in Pakistan. As a result, there is limited information of production available to producers.
New entrants and existing procedures must be prepared to stay up-to-date concerning agronomic practices, development in new varieties and extraction procedures.
A Ph.D. research programme has been completed at the Institute of Horticulture Sciences, University of Agriculture, Faisalabad, under the project “Export Quality Cut Flower Production and Essential Oil Extraction of Rosa” sponsored by the ministry of science and technology, Islamabad.
The focus of project was to develop production process for a non-traditional high value crop and popularize this knowledge to farmers to introduce this crop in cropping system. Framers, growers and industrialists are the main beneficiaries of this research.
The major consumers of rose essential oil are the US (40 per cent), Western Europe (30 per cent) Japan (7 per cent) and rest of the world (23 per cent). At present, top quality rose oil sells for around $35 per 5ml on the wholesale market. Hence, rose oil is an essential commodity for marketing at competitive price.
Efforts should be made to produce export quality essential oil in sufficient quantity. An effective marketing system and a large-scale campaign for motivation of the farmers for essential oil production are very necessary.