The present invention introduces a new ready-to-drink tea beverage, prepared from brewing the herb species Sideritis raeseri, Sideritis scardica, Sideritis syriaca, Sideritis perfoliate! ssp. athoa, known as the "Greek Mountain Tea" and the production methodology thereof.

BACKGROUND OF THE INVENTION

The genus Sideritis contains a large variety of plant species consisting of herbaceous annual or perennial herbs - medicinal plants belonging to the family of Cheilanthon (Lamiaceae). Over 350 different species of the genus Sideritis they have been recorded to date, most of them native to the Mediterranean region. Greece has recorded about 17 endemic species, of which the principal are the Sideritis perforliata ssp. athoa or Mount Athos tea, the Sideritis cladestina or Taygetos tea, the Sideritis euboea or tea of Evia, the Sideritis raeseri or Parnassus tea, the Sideritis scardica or Olympus tea and the Sideritis syriaca or Malotira of Crete tea (ref . 1).

The genus Sideritis is widely used in traditional medicine due to its beneficial therapeutic properties. The beverage known as "mountain tea" is prepared after brewing the herb in boiling water. It is a delicious drink that is consumed in widely in Greece, especially during the winter months because of its positive action against colds and infections of the upper respiratory system. According to traditional knowledge and practice, the brewed "mountain tea" shows warming, tonic, diuretic, detoxifying, healing and antiseptic properties (ref. 1). In recent years, the interest in systematic and thorough research of the pharmacologically active substances of the genus Sideritis is rapidly increasing, with the view to their potential application in food, drugs and cosmetics. According to scientific studies, the chemical composition of the plant seems to be quite complex: polyphenols, diterpenes, alkaloids, sterols, amino acids, carbohydrates, proteins, chlorophylls, volatile compounds, minerals, metals and other unidentified compounds form the basic composition of the herb .

Among all these different substances, the most interesting group of chemical compounds are those with antioxidant properties. Antioxidant compounds protect the body from oxidative stress, which is believed to contribute to the development of a wide range of diseases such as Alzheimer's, Parkinson's disease, cardiovascular disease, rheumatoid arthritis etc. According to modern nutritional trends, increased intake of antioxidants contributes to better health, wellness and the delay of aging phenomena (ref. 8).

To investigate the pharmacologic and antioxidant properties of the genus Sideritis, a number of studies have been conducted both in various plant extracts, as well as in the chemical compounds that have been isolated from them. The species of the genus Sideritis contain many active ingredients in various combinations and concentrations. The pharmacological properties of the plants are mainly due to three phytochemical groups that exist in them: the flavonoids, the diterpenes and the volatile compounds.

The primary beneficial aspects of the active ingredients that have been reported in the literature are:

Antioxidant activity. The most important antioxidant compounds are flavonoids which have been identified as 5 - and 8 - disubstituted flavones {ref. 9), glucosidic flavonoids (ref. 5), unsweetened flavonoids, poly-hydroxy-flavones (ref. 11) and similar plenyl-propanol compounds with significant antioxidant activity (ref. 3). According to the above studies, the tea of the genus Sideritis presents moderate to strong antioxidant effects, depending on the type of plant, season of harvest, plant species and extraction method. The total phenolic content in the species of the genus Sideritis, ranges between 30 - 400 mg gallic acid equivalents/g extract (ref. 14, 15). The main phenolic components that characterize the genus Sideritis is chlorogenic acid, myricetin, isocoutellarein, catechin, apigenin, vanillic acid and the gallate ester of epicatechin (ref. 11). Anti-inflammatory activity. It has been identified in several species of the genus Sideritis and it is mainly attributed to flavonoids and the diterpenic compounds, (ref 4, ref 16).

Antimicrobial activity. Mainly due to the alkaloids, the phenolic components in essential oils and various terpenoids. Research has shown strong activity against mainly Gram-positive bacteria, yeasts and fungi (ref. 2, 6), and moderate antimicrobial activity against Gram negative bacteria (ref. 10).

Other beneficial effects such as analgesic, anti-gastric ulcer (ref. 16), antihypertensive (ref. 13), calmative and antitussive action (ref. 15). Recent years, a new trend that combines the use of natural products with medicinal properties to the novel food and beverage composition is increasingly recorded worldwide. The use of the herb of the genus Sideritis in new products can be tailored to the needs and pace of modern life and can address the new nutritional trends of natural origin products, rich in beneficial substances for the human body.

REFERENCES

1. Gabrieli, C, (1999). Physico-chemical and pharmacological study of the plant Sideritis raeseri ssp. raeseri «mountain tea." Practicals of the training course of National Greek Pharmacological Society, June 19-20 Pertouli Greece.

2. Aligiannis N, Kalpoutzakis E, Chinou IB, Mitakou S, Gikas E, Tsarbopoulos A. 2001.

Composition and antimicrobial activity of the essential oils of five taxa of Sideritis from Greece. J Agric Food Chem. 2001 Feb; 49(2): 811-5.

3. Armata M., Gabrieli C, Termentzi A., Zervou M., and okkalou E., (2008). Constituents of Sideritis syriaca. ssp. Syriaca (Lamiaceae) and their antioxidant activity. Food Chemistry 111, 179-186.

4. Cabrera C, Nez R.G., and Pez, M.C.L., (2003). Determination of Tea Components with Antioxidant Activity. J. Agric. Food Chem. 2003, 51, 4427-4435.

5. Charami M.T., Lazari D., Karioti A., Skaltsa H., Hadjipavlou-Litina D., and Souleles C, (2008). Antioxidant and Anti-Inflammatory Activities of Sideritis perfoliate subsp. Perfoliata (Lamiaceae). Phytotherapy Research, 2008, 22, 450-454.

6. Diaz R.M., Garcia-Granados A, Moreno E., Parra A, Quevedo-Sarmiento J., Saenz de Buruaga A, and Saenz de Buruaga J.M. : Studies on the Relationship of Structure to Antimicrobial Properties of Diterpenoid Compounds from Sideritis. Planta Medica 1988

7. Escribano-Bailo ^' n, M.T., Santos-Buelga, C, 2003. Polyphenol extraction from foods.

In: Santos-Buelga, C, Williamson, G. (Eds.), Methods in Polyphenols Analysis. RSC, Cambridge, UK, pp. 2-16.

8. Finkel T. and Holbrook N. J., (2000). Oxidants, oxidative stress and the biology of ageing. Nature, 48, 239-247. 9. Gabrieli, C. N., Kefalas, P. G., & okkaiou, E. L. (2005). Antioxidant activity of flavonoids from Sideritis raeseri. Journal of Ethnopharmaco!ogy, 96, 423-428.

10. Gergis V, Spiliotis V., and Poulos C, (1990). Antimicrobial Activity of essential oils from greek Sideritis species Pharmazie, 45, 1-1.

11. Janeska B., Stefova ., Alipieva K., (2007). Assay of flavonoid aglycones from the

species of genus Sideritis (Lamiaceae) from Macedonia with HPLC-UV DAD. Acta Pharm. 57, 371-377.

12. Kunze, W., (1998). Technologie Brauer und Malzer. Wolfgang Kunze, VLB Berlin.

13. Paya M., Terencio M.C., and Villar A., (1985). Hypotensive activity from some mediterranean medicinal plants. Acta Agronomica Academiae Scientiarum

Hungaricae 34, 90.

14. Pljevljakusic D., Savikin K., Jankovic T., Zdunic G., Ristic M., Godjevac D., and Konic- Ristic A., (2011). Chemical properties of the cultivated Sideritis raeseri Boiss. & Heldr. subsp. raeseri. Food Chemistry, 124, 226-233.

15. Tunalier Z., Kosar M., Ozturk N., and Baser .H.C., (2004). Antioxidant properties and phenolic composition of Sideritis species. Chemistry of natural compounds, 40, 4, 206-210.

16. Villar A., Gasco M.A., and Alcaraz, M.J., (1984) Anti-inflammatory and anti-ulcer properties of hypolaetin-8-glucoside, a novel plant flavonoid J Pharm Pharmacol. 36:820-3

GENERAL DESCRIPTION OF THE INVENTION

The present invention aims to produce a ready-to-drink tea beverage, which is produced from brewing the herb Sideritis, known in Greece as "mountain tea". For this invention, several aromatic herb species of the genus Sideritis were selected. More specifically, the main herb species that were chosen are: Sideritis raeseri, Sideritis scardica, Sideritis syriaca and Sideritis perfoliata ssp. athoa. All these herbal species have never been used before for the production of brewed ready-to-drink beverages. All above species are endemic in Greece and have shown to sustain a significant amount of active substances beneficial to human health and wellbeing, such as the chemical group of antioxidant flavonoids as well as various essential oils.

The invention holds its roots from the local traditional practice, where the herb is consumed after brewing it in hot water. It features the production of a novel ready to drink tea product, which differs radically from the customary ready to drink preparations sold as « ice tea» products. Until now, these products contained water, sugar and a very low concentration of tea extract (usually less than 1 mL / 1000 mL of product). The new, innovative product is based on a dramatically different that excludes the addition of tea extract to water but alternatively, it is produced by a 100% natural brewing of the herb, the same way that it has been used in traditional medicine and cultural practice for many years.

The invention steps for producing the mountain tea product include: the appropriate creation of a new production process with an emphasis on a specially designed water treatment, the selection of appropriate technological means and the planning of the industrial production specific parameters. All processing steps are suitably programmed so as to create a product with high quality sensory characteristics and a considerable amount of beneficial substances.

In order to succeed in a production of an optimal product of high nutritional value, the design of an exclusive water treatment capable to extract high levels of antioxidant compounds from the raw material was designed. In addition, the outline of two successive filtration treatments was planned, so as to remove unwanted foreign materials, aggregates and flocculation resulting from the brewing process.

The designed water and filtration treatments succeed to produce a crystal clear product with a significant level of herbal active substances. In particular, the filtration process with bentonite (aluminium phyllosilicate, a strong clarification agent) in combination with specific acidification removed the blurring of the protein by adsorbing relatively large amounts of protein molecules from the brewed solution, while simultaneously preserved the highest percentage of beneficial phenolic components of the natural tea herb.

The methodology described below has resulted in a product with significant concentrations of antioxidants and other beneficial compounds of the herbal raw material. The innovative product has excellent sensory properties and is highly accepted by the consumers. The product also maintains a significant number of favorable aromatic elements of the herb, mainly from the flower part of the herb Sideritis. The product can be consumed cold as «ice tea», but also hot after thermal heating.

THE STAGES OF THE PRODUCTION PROCESS

1. Incoming receipt of the herbs in fresh or dried form and separation of the flowering part from the rest of the raw material.

2. Water treatment, exclusively designed to optimize the receiving of all valuable pharmacological and flavors of the herb. The water treatment is particularly crucial for the proper extraction of plant constituents and mainly involves three stages: a)desodification (removal of the carbonate alkalinity by creating carbon dioxide gas and insoluble calcium carbonate), b) Filtration with active carbon filter (deodorization, removing organic debris) and c) Addition of calcium chloride (increase of non-carbonate hardness and in particular calcium). The special water treatment leads to a certain proportion of carbonate and non carbonate hardness, which is necessary for maximum extraction of active ingredients of the tea, by as well maintaining pleasant organoleptic characteristics of the final product (flavor, taste and odor).

In order to successfully control the success of this stage, the critical parameter that is monitored is the residual alkalinity (RA-residual alkalinity). The residual alkalinity of the water reflects the competition between pH increase and decrease factors, in combination with the forms of the water hardness. The parameter is assessed by the equation: RA = Carbonate Hardness - [(Calcium Hardness + 0.5 Magnesium Hardness) / 3.5]. From the pilot product testing it has been estimated that the maximum release of active substances in combination with the best sensory properties are obtained when the parameter of RA treated water is less than 1, with typical values -0.3 and -0.8 as pH 6, 2 to 6.8. In this range of RA, the sense of "bitter" that may result from the brewing process can be significantly reduced (ref. 12). Also, when the pH value is situated at least 2 pH units above the pK of free phenolic acids, a more efficient phenolic acid extraction is accomplished from the herbal material (ref. 7). From the pilot tests, it has been estimated that in cases of pH near neutral (7.0), a significantly greater quantity of antioxidant compounds can be achieved (data on Table 1).

3) Brewing of the herbal tea with the pre-treated water. At this stage, the extraction of all important components of the herb is performed by brewing the herb for 2 to 10 minutes at a temperature> 95 ° C. The average ratio of herb / water is between 2 to 10 grams of raw material/liter. In the brewing process, the water receives all the useful and beneficial substances in the herb. For this reason, the control of the brewing process is particularly critical for the quality of the final product and therefore it is strictly controlled by the selection and mixing the appropriate raw material, the herb concentration, as well as the time and temperature of brewing.

4) First filtering, after cooling the product at room temperature. This stage is performed by using filter plates and cellulose plates or by applying the technique of tangential microfiltration or ultra filtration, or by centrifugation. At this point all possible residues from the raw material are removed, such as a percentage of the proteins that may cause blurring of the product, as well as other precipitants and other sediments. The above filtration systems were chosen because of their ability to retain foreign bodies, but at the same time to allow the beneficial ingredients of the herb be sustained in the final product.

5) Control and pH adjustment. This step the plays an important role in the subsequent production steps. The pH of the extract before adding bentonite in the next stage must be in any case below the valye of 4.0, so that the bentonite can operate effectively.

6) Application of bentonite. Bentonite is a colloidal form of clay, charged with a negative charge. The material is characterized by its large adsorptive capacity and the strong interaction ability with positively charged particles such as proteins, which are retained by bentonite and afterwards can be removed by precipitation. The addition of bentonite is one of the critical factors of the invention, due to the functional ability to remove the blurring and result to an acceptable, high quality final product with clear and bright appearance (data in Table 2). The addition of bentonite is averaging between 3 - 9 g / hL in an inert atmosphere (N ₂ and /or C0 ₂ ), so as to protect active antioxidant ingredients sensitive to oxidation and also to avoid microbial growth. The total application of bentonite must last not less than 24 hours. Under these conditions and with the appropriate combination of bentonite, this process can be accomplished by also maintaining a high percentage of antioxidants and other active ingredients, as well as the favorable aromatic compounds of the raw material (Data on Table 3).

7) Second and final filtration product for removing bentonite and aggregates. The final product is acceptable, when a measured turbidity is below 3 EBC-turbidity measured with scatter light/transmission units (data on Table 4).

8) Addition of sweeteners, natural, synthetic or semi synthetic (e.g. sugar, honey, aspartame, sucralose, must, etc).

9) Addition of herb extracts and other herb brews such as Oregano [Oregano vulgare L), dittany (Dictamnus albus), Peppermint {Mentha L), sage {Salvia L), Linden {T ia L ), Chamomile {ChamomiHa L), Marjoram {Origanum majorana L.) Ginger, Gingko, Eucalyptus, Cardamom, Fennel {Foeniculum vulgare), etc.

10) Addition of natural flavoring ingredients or flavor enhancers for example, fruit juices or concentrates, fruit extracts, natural aroma extracts etc. 11) Addition of other auxiliary agents (eg, stabilizers, thickeners, sequestrants, anti-caking agents).

12) Final control and pH adjustment amongst 2.8 - 3.4 with the use of acidification medium and acidity regulators (citric acid, ascorbic acid, malic acid and their salts, magnesium chloride, etc.).

13) Pasteurization of the finished product. This step is necessary for the sufficient shelf life of the product in room temperature storage. Various types of pasteurization can be used, for example in-pack pasteurization, flash pasteurization, hot-filling, high-pressure, in temperatures starting from 60-70° C and various time-temperature combinations (eg 85 - 95° C for 15-60 seconds).

14) Addition of packaging gases (e.g. N ₂ , C0 ₂ )

15) Packaging into containers of various types and sizes (aluminum, glass, plastic polymers, aseptic packaging, etc.), appropriate for storage and distribution. According to the described production process, the estimated lifetime of the product is 12 months, depending on the exact composition, the supplementary ingredients, the pasteurization time and the packaging type.

Another key element of the novel product is the nutritional aspect of 100% absence of caffeine (data on Table 5), in contrast to all black and green tea products. Therefore, the product of current invention can be consumed by all consumer groups that avoid the consumption of caffeine, such as children, pregnant women, people in homeopathy etc.

The described methodology results in the production of an innovative ready to drink tea with a significant concentration of antioxidants, highly active compounds that are unique and characteristic of the genus Sideritis, such as chlorogenic acid, catechin, apigenin, myricetin, isocoutellarein, vanillic acid and the gailate ester of epicatechin (data on Table 6). Table 1. Effect of water pH in the concentration of antioxidant compounds (expressed as mg Gallic acid / L).

Table 2. Effect of bentonite concentration in the protein concentration of two innovation products by two different species of the genus Sideritis.

*Proteins determined with the Kejdahl analytical method

Table 3. Analysis of total phenolic compounds before using bentonite and in the final products of the invention, produced by two different species of the genus Sideritis.

*Total phenolic determined by ISO 14502-1 - Colorimetric method using Folin - Ciocalteu reagent Table 4. Effect of bentonite in the turbidity of the final product of the invention, produced by two different species of the genus Sideritis.

Table 5. Caffeine concentration in the products of the invention, produced by two different species of the genus Sideritis.

* Caffeine concentration determined with HPLC-DAD.

Table 6. Analysis of free phenolic compounds in the products of the invention, produced by two different species of the genus Sideritis.

a Free Phenolic Compounds identified and determined with HPLC-DAD.