Satureja hortensis (PROSEA)
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Introduction |
- Protologue: Sp. pl.: 568 (1753).
- Family: Labiatae
- Chromosome number: 2n = 46, 48
Synonyms
- Satureja pachyphylla K. Koch (1843),
- S. laxiflora K. Koch (1849),
- Clinopodium hortense Kuntze (1891)
Vernacular names
- Summer savory, annual savory (En)
- Sarriette annuelle, sarriette, savourée (Fr)
Origin and geographic distribution
Satureja hortensis is native to the eastern Mediterranean region and widely escaped from cultivation elsewhere. It was probably grown as a condiment in ancient Rome. Since then, it has been planted in Europe, Asia (the former Soviet Union, Afghanistan, India, Sri Lanka), South Africa and the Americas (United States, Argentina). In South-East Asia, it is cultivated in the Philippines on a small scale for the fresh-herb market and similarly in the mountains of Java (Indonesia).
Uses
Summer savory, either fresh or dried, is mainly used for flavouring. For the fresh product, all aerial plant parts are used, but for the dried herb, only leaves and flowering tips. The best class of commercial summer savory consists of dried leaves only.
Its main traditional culinary use in Europe is as a flavouring for vegetables, especially beans and peas. In several countries (e.g. Germany, the Netherlands) the vernacular name is the local equivalent of "bean herb”. Summer savory blends well with other herbs. Alone or in combination with other herbs it is quite widely used to flavour baked products, meat and meat products (e.g. sausages), egg dishes, processed vegetables, salads, soups, gravies and pickles.
Summer savory contains an essential oil with a sharp and bitter flavour. At low concentrations only it is reminiscent of the herb itself. The oil is used in the food industry to flavour processed foods, and in the liqueur and perfume industries. The maximum permitted level in food products is about 0.04%. Sometimes an oleoresin is produced, but in commercially insignificant amounts. In the United States the regulatory status "generally recognized as safe” has been accorded to summer savory (GRAS 3012), summer savory oil (GRAS 3013) and summer savory oleoresin (GRAS 3014).
Summer savory is used in traditional medicine as a carminative, expectorant, astringent and tonic in the treatment of gastro-intestinal disorders (cramps, nausea, indigestion, diarrhoea), and sore throat, generally in the form of a tea. It has also been used as an aphrodisiac. Fresh summer savory is rubbed on the skin to treat insect bites, e.g. bee stings.
Summer savory has also been planted as a bee-feeding plant.
Production and international trade
The main countries producing summer savory include France, Spain, the former Yugoslavia and the United States. Only small quantities are traded internationally and no recent statistics on production and trade are available.
Properties
Dried savory has a fragrant, aromatic odour, and a warm, aromatic, slightly sharp and somewhat camphoraceous taste. The odour and taste are sometimes likened to those of thyme (Thymus vulgaris L.).
Fresh green herb (leaves and flowering tops), collected at the end of the flowering period, contains per 100 g: moisture 72 g, protein 4.2 g, fat 1.65 g, carbohydrates 11.5 g, fibre 8.6 g and ash 2.1 g. Dried leaves are reported to contain per 100 g edible portion: water 9.0 g, protein 6.7-7.7 g, fat 5.2-5.9 g, carbohydrates 53.4-54.6 g, fibre 15.3 g, ash 8.7-9.6 g (Ca 2132 mg, Fe 38 mg, Mg 377 mg, P 140 mg, K 1051 mg, Na 24 mg, Zn 4 mg), vitamin A (as β-carotene) 5130 IU, niacin 4 mg, and vitamin C 12 mg. The energy value is 1130-1500 kJ/100 g.
The odour and taste of summer savory are due to the presence of 1-2% essential oil in the leaves and flowers. The essential oil is golden yellow with a fresh medicinal-spicy odour reminiscent of sage and thyme, and can be obtained by steam distillation. More than 100 components of the essential oil have been described, but the major components are carvacrol (a monoterpene phenol), γ-terpinene, and p-cymene.
Carvacrol (C10H14O) is a colourless to pale yellow liquid, with a pungent, thymol odour, imparting a fresh, slightly sharp, phenolic sensation. Commercial savory oil must contain 20-57% carvacrol, whereas the thymol content should be negligible.
The relative amounts of the volatile compounds in the essential oil is different from those in the ground herb itself, because steam distillation leads to changes in the composition. The main volatile compounds of ground herb are γ-terpinene, p-cymene, α-pinene, α-terpinene and myrcene.
Ground dried leaves and leaf extracts, especially the ethanol extract, of summer savory have shown antioxidant activity in pork meat and sunflower oil respectively, and summer savory has been proposed as a source of natural antioxidants to stabilize lipids and lipid-containing products. An important antioxidant compound in summer savory is rosmarinic acid.
The essential oil has antifungal and antibacterial activity. Carvacrol is responsible for antifungal activity against e.g. Cladosporium herbarum and Penicillium glabrum. The compounds with the greatest antibacterial activity are carvacrol, 1,8-cineole, p-cymene, eugenol, β-humulene, linalool, β-pinene, α-terpineol and thymol, with the test bacteria Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella pullorum, Staphylococcus aureus, Streptococcus faecalis and Yersinia enterocolitica. The essential oil has spasmolytic effects on isolated smooth muscles. A monograph on the physiological properties of summer savory has been published by the Research Institute for Fragrance Materials (RIFM).
The seeds of summer savory contain, on a dry basis, 42% oil and 24% protein. The seed oil is said to be equal or superior to linseed oil as a drying oil, and contains: linolenic acid 60-65%, linoleic acid 18-24%, oleic acid 4-12%, palmitic acid 2-4% and stearic acid 1-3%.
The weight of 1000 seeds is 0.5-0.8 g.
Composition
Summer savory oil (from Poland) (Source: Gora et al., 1996.)
- 40.9% γ-terpinene
- 39.3% carvacrol
- 6.2% para-cymene
- 4.0% α-terpinene
- 2.5% myrcene
- 1.9% α-thujene
- 1.5% α-pinene
- 0.8% β-caryophyllene
- 0.8% β-pinene
- 0.6% β-bisabolene
- 0.3% limonene
- 0.3% β-phellandrene
- 0.3% α-phellandrene
- 0.1% terpinen-4-ol
- 0.1% camphene
- 0.1% sabinene
- 0.1% methyl carvacrol
- 0.1% α-terpineol
- trace α-bisabolene
- trace borneol
- trace trans-carveol
- trace trans-dihydrocarvone
- trace germacrene B
- trace α-humulene
- trace linalool
- trace cis-sabinene hydrate
- trace β-sesquiphellandrene
- trace spathulenol
- trace thymol
- 100.1% total
Adulterations and substitutes
The perennial winter savory (S. montana L.) contains an essential oil which is very similar to that of summer savory, and can be used as a substitute. However, the flavour of winter savory is regarded somewhat inferior to that of summer savory. The chemical composition of oregano (Origanum vulgare L.) oil resembles that of savory, but the oil has a coarser character. Thyme (Thymus vulgaris) oil is occasionally used as an adulterant of savory oil. Another adulterant of summer savory is Thymbra spicata L. (Turkey, Greece).
Description
- Erect, much branched, very aromatic, annual herb, 10-50 cm tall. Stem obtusely angular to subterete, without furrows, with short hairs.
- Leaves decussately opposite, subsessile; blade linear to lanceolate or obovate, 1-4 cm × 1-5 mm, base gradually tapering into very short petiole, margin entire, apex obtuse to rather acute, usually subglabrous but densely gland-dotted.
- Inflorescence consisting of lax to densely congested verticillasters each with 2-20 bisexual flowers; pedicel very short; bracteoles usually longer than calyx, thinly long-ciliate.
- Calyx tubular and 2-lipped, 3-4.5 mm long, 10-veined, glabrous inside, thinly pilose outside, with 5 subequal triangular teeth (longer than the tube) or upper lip 3-dentate and lower lip 2-dentate; corolla tubular and 2-lipped, 4-10 mm long, tube widely funnel-shaped, lower lip 3-fid, upper lip emarginate, light violet to white, in the throat sometimes red-dotted, thinly pubescent outside; stamens 4, curved, inserted in the upper half of the corolla tube under the upper lip, shorter than the corolla; pistil with 4-lobed ovary and a style with 2 equal branches each ending in a small stigma.
- Fruit composed of 4 nutlets, enclosed within the persistent calyx; nutlet subglobose, about 1 mm long, glabrous, smooth, blackish-brown.
Growth and development
Germination of summer savory is slow and normally takes 2-3 weeks, but may take longer under unfavourable conditions. Initial development after germination is fast. Flowering starts 75-80 days after germination, and fruits ripen continuously and may shatter. In Europe, the period from germination to ripening of the seeds is about 140-160 days.
Three major development phases can be distinguished in the crop cycle of summer savory: the vegetative phase, the flowering phase, and senescence. The vegetative phase ends when the flower buds appear. The flowering phase may be subdivided into early and full flowering, the latter starting when the first flowers are fully open. The rate of dry matter production increases progressively until the start of the flowering phase, after which the rate remains constant until the maximum biomass is attained and senescence starts. Though the biomass production varies with season, planting date and level of fertilizer application, the relationship between the course of dry matter production and reproductive development remains the same.
Other botanical information
Sometimes Satureja is erroneously spelled Satureia. The genus Satureja L. is taxonomically badly known and needs revision; in a wide sense about 200 species are accepted, in a strict sense about 30 species. S. hortensis is extremely variable in all its characteristics; subclassifications are numerous, but all differences gradually change from one extreme to the other and cultivated forms are indistinguishable from wild forms. S. hortensis is called "summer savory”; "winter savory” is S. montana L., also originating from the Mediterranean and used for flavouring like summer savory, but considered inferior. Their main differences are: summer savory is a slightly larger annual, with narrow and slightly pubescent leaves and a sweeter, less piquant taste; winter savory is a slightly smaller perennial with narrower and glabrous leaves and a less sweet, more piquant taste.
Ecology
Summer savory grows well in most temperate and subtropical climates in full sun on light, rich, well-drained soils. It is native on calcareous soils in the Mediterranean region, and prefers alkaline soils.
Propagation and planting
Propagation of summer savory is usually by seed. Information on planting practices is only available from Europe and the United States, where summer savory is sown shallowly in rows or broadcast. Seeds should be sown 0.5-1.5 cm deep at a row distance of 25-30 cm. When mechanically cultivated, rows may be 45-50 cm apart. Too narrow spacings may increase the risk of fungal diseases like grey mould (Botrytis cinerea) and mint rust (Puccinia menthae). Sowing rates range from 3 to over 10 kg seed per ha. Seeds remain viable for 1-2 years, but can be stored for several years in airtight containers. Adequate soil preparation before planting is very important.
Husbandry
Summer savory is sometimes thinned when plants have 4-6 leaves (to 15 cm apart in the United States). The field must be kept free from weeds, either mechanically or chemically. Fertilizer application is usually recommended, with an adequate supply of potassium being particularly important. However, excessive fertilization may lead to lodging in the flowering phase. Per 10 t fresh material of summer savory in Germany 32 kg N, 13 kg P2O5, 51 kg K2O, 7 kg MgO and 35 kg CaO is taken up from the soil. In Scotland, fertilizer application has no influence on the essential-oil concentration and oil composition, but leads to an increased biomass and thus a higher oil yield. In Europe, it is recommended to grow summer savory or other Labiatae and to return to the same field only once in 5 years, to prevent the build-up of large populations of disease and pest organisms.
Diseases and pests
Mint rust (Puccinia menthae), an important disease of mints (Mentha spp.), occurs on the leaves and stems of summer savory, but without causing as much damage as in mints. In Europe, Pythium fungi cause damping-off of young summer savory, whereas false mildew (Peronospora spp.) and grey mould (Botrytis cinerea) can be troublesome.
Pests on summer savory in Europe include leaf miners (Phytomyza horticola), caterpillars (Apterona crenulella, Arctia caja), aphids (Aphis fabae), cicadas (Cicadella atropunctata) and beetles (Cassida viridis).
Harvesting
Summer savory should be harvested when flowering. Plants are cut at ground level or above the bottom branches. Under favourable weather conditions a ratoon crop can be obtained.
Yield
Yields of summer savory may vary considerably. In Scotland, dry matter yields ranging from 1.4-11.3 t/ha have been found. The oil content was 0.4-0.8% during the vegetative phase, rising to 0.8-1.2% in the early flowering phase to a maximum of 1.4-2.0% at full flowering, and falling sharply to 0.4% during senescence. Maximum oil yield per ha coincided with full flowering, and ranged from 16-60 kg/ha. The oil composition varied between and within seasons, but the carvacrol content of the oil was always according to international standards (20-57%) during the flowering phase. Consequently, harvesting at maximum biomass gave the highest yield of oil of acceptable quality. These dry matter yields are similar to or higher than those for Eastern Europe. However, higher essential-oil concentrations (2-4.7%) and oil yields (60-110 kg/ha) have been obtained in Poland. Experimental yields for Germany are 33-49 t/ha fresh herb, which is equivalent to 5.6-7.5 t/ha dried herb, and fresh yields of leaves and flowering tips, separated from the stems, of 10-22.5 t/ha, equivalent to a dry weight of 1.6-4.1 t/ha.
Handling after harvest
The cut herbage of summer savory is usually dried, threshed and cleaned, and then stored in closed containers to maintain the colour and to avoid loss of the essential oil. The harvested material should be dried soon after harvest, to avoid loss of quality. Air-dried summer savory keeps its flavour and odour well, but freeze-dried material loses its odour and flavour rapidly when stored in an atmosphere with oxygen (e.g. glass jars or paper bags). The essential oil is obtained by steam distillation of the whole dried herb.
Genetic resources
Germplasm collections are available at several research institutes in Europe, e.g. at the Vavilov Research Institute of Plant Industry, St. Petersburg, Russia (58 accessions) and at the Gene Bank Department of the Research Institute of Crop Production, Olomouc-Holice, Czech Republic (27 accessions).
Breeding
Little selection has been done in summer savory. In experiments, inter-plant variability in dry matter production is large, which is commonly observed in crops that have undergone little improvement.
As the effects of crop management on the oil content of summer savory seem limited, selection and breeding of improved plant types is important to obtain cultivars with higher oil content. In Poland for instance, a hybrid ("Saturn”) of Yugoslavian and Polish material has been bred; it has a high oil yield (4.5% in air-dry herb) and relatively little stem material.
Prospects
The present importance of summer savory in South-East Asia is limited. It is only grown on a very limited scale and is not used in traditional food and medicine. Although there may be some scope for production expansion because of the demand from European-style hotels, restaurants, and fast-food chains, this situation will probably remain. Production for international markets is probably not a viable option, because the produce will have to compete with production in temperate and subtropical regions with climates more similar to its natural habitat.
Literature
- Guenther, E., 1949. The essential oils. Vol. 3. Van Nostrand, Toronto, Canada. pp. 739-744.
- Hay, R.K.M., 1993. Physiology. In: Hay, R.K.M. & Waterman, P.G. (Editors): Volatile oil crops: their biology, biochemistry and production. Longman, Harlow, United Kingdom. pp. 26-31.
- Leung, A.Y. & Foster, S., 1996. Encyclopedia of common natural ingredients used in food, drugs and cosmetics. 2nd edition. John Wiley & Sons, New York, United States. pp. 465-466.
- Prakash, V., 1990. Leafy spices. CRC Press, Boca Raton, Florida, United States. pp. 89-93.
- Rosengarten, F., 1973. The book of spices. Revised edition. Pyramid, New York, United States. pp. 388-392.
- Sváb, J. & Hornok, L., 1992. Summer savory (Satureja hortensis L.). In: Hornok, L. (Editor): Cultivation and processing of medicinal plants. John Wiley & Sons, Chichester, United Kingdom. pp. 218-220.
- Svoboda, K.P., Hay, R.K.M. & Waterman, P.G., 1990. Growing summer savory (Satureja hortensis) in Scotland: quantitative and qualitative analysis of the volatile oil and factors influencing oil production. Journal of the Science of Food and Agriculture 53(2): 193-202.
- Svoboda, K.P., Hay, R.K.M. & Waterman, P.G., 1990. The growth and volatile oil yield of summer savory (Satureja hortensis) in a cool wet environment. Journal of Horticultural Science 65(6): 659-665.
Sources of illustrations
Mansfeld, R., 1986. Verzeichnis landwirtschaftlicher und gärtnerischer Kulturpflanzen (ohne Zierpflanzen) [Register of agricultural and horticultural plants in cultivation (without ornamentals)]. Schultze-Motel, J. et al., editors 2nd edition. Vol. 3. Springer Verlag, Berlin, Germany. Fig. 163, p. 1164. Redrawn and adapted by P. Verheij-Hayes.
Authors
- Dzuong Duc Huyen & M. Brink
