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This study aimed to investigate the influence of real storage conditions and daily consumption, heating, and presence of food during storage (dried tomatoes, cheese) and heating (vegetables) of monovarietal EVOOs on its fatty acid composition, phenolic and volatile compounds, antioxidant activity, sensory properties, and quality. The results indicated that under consumption conditions used in this study (gradual headspace increasing, darkness, room temperature), EVOO's composition of fatty acid, phenolic and volatile compounds remained preserved within one month. The presence of food during storage and heating significantly decreased the quality and the concentration of total identified phenolic and volatile compounds of the used EVOO. The use of monovarietal oils indicated varietal specificity under different conditions of its use, related to the composition of fatty acids, phenolic and volatile compounds. Cilj ovog istraţivanja bio je ispitati utjecaj realnih uvjeta upotrebe i svakodnevnog korištenja, zagrijavanja i prisutnosti hrane tijekom skladištenja (sušena rajĉica, sir) i zagrijavanja (povrće) sortnih EDMU na sastav masnih kiselina, fenola i hlapljivih spojeva, antioksidacijsku aktivnost, senzorska svojstva i kvalitetu ulja. Dobiveni rezultati pokazali su da je sastav masnih kiselina, fenolnih i hlapljivih spojeva EDMU u uvjetima svakodnevnog korištenja (postepeno povećavanje nadprostora boce, bez svjetlosti, sobna temperatura) ostao nepromijenjen unutar mjesec dana skladištenja. Prisutnost hrane tijekom skladištenja i zagrijavanja znaĉajno je utjecala na smanjenje kvalitete te koncentracije ukupnih identificiranih fenolnih i hlapljivih spojeva korištenog EDMU. Primjenom sortnih ulja utvrĊena je sortna specifiĉnost u razliĉitim uvjetima uporabe vezana uz poĉetni sastav masnih kiselina, fenolnih i hlapljivih spojeva.

The health benefits of the Mediterranean diet have been associated with the consumption of extra virgin olive oil (EVOO) as the main source of fats. Nowadays, the usage of EVOO as cooking oil to prepare meals is highly recommended. During heating, the oil undergoes several chemical reactions that influence its chemical composition and quality. Therefore, this study aimed to investigate the influence of heating on quality parameters, phenolic and volatile compounds in Leccino, Istarska bjelica, and Buža monovarietal EVOO. The oil samples were submitted to heating in an air oven at two different temperatures (180 °C and 220 °C), simulating usual roasting conditions typical for Mediterranean cuisine. Fresh, unheated oil was used as a control. Quality parameters related to oxidation status of oil, peroxide value, and spectrophotometric indices (K232, K268, and ΔK) were determined according to the analytical methods described in the European Commission Regulation from 1991, amendments included. The composition of phenolic compounds was determined by HPLCDAD, and volatiles’ profiles using SPME and GC-FID techniques. Significant losses in oxidative stability and decrease in phenolic and volatile compounds were more pronounced at higher heating temperatures, which underlined the temperature dependency of oxidative degradation during cooking conditions. However, there was still a considerable amount of phenolic compounds preserved after heating. In addition to quality parameters that served as oxidation indicators, hydroxytyrosol acetate among phenolic compounds and octanal, (E)- 2-octenal, hexanal, 3-pentanone, and 1-penten-3- one among volatiles, were underlined as possible thermal oxidation markers. Aside from being influenced by the heating temperature, the changes in the phenolic composition were cultivar dependent, while the changes in the composition of volatile compounds were found to be caused primarily by the heating temperature with no significant influence of the cultivar as an investigated factor. The obtained results contribute to the understanding of changes in quality and composition of Croatian monovarietal EVOO after heating, as well as provide new insights on the preservation of bioactive compounds in the course of the cooking process. Acknowledgement: This work has been supported by the Croatian Science Foundation under the project “Young researchers' career development project – training of new doctoral students”, DOK-2018-09-2293.

Virgin olive oil (VOO) is highly appreciated due to its exceptional sensory characteristics. During the VOO sensory analysis (panel test), oils are classified into quality categories based on the intensity of the predominant defect and the fruity attribute. The use of reference materials (RM) for VOO sensory evaluation is a fundamental tool to ensure the effectiveness of the panel test performance. For that purpose RM from natural matrix are commonly used, however there are some limitations regarding limited amounts available and low homogeneity. Therefore, the setting up of artificial and reproducible RMs in order to increase the proficiency of the sensory panels was one of the objectives of the H2020 OLEUM project. In this review, the process of development and validation of two artificial RMs, for the winey-vinegary and rancid defect, are summarized. During the validation, representativeness, the panels’ detection threshold for RMs, and shelf-life of RMs were evaluated. The utilization of proposed artificial RMs could improve the effectiveness of the method by offering advantages as reproducibility over time and unlimited availability. Further studies, involving formulation of RMs for other specific VOO sensory attributes, are of great importance. This work was developed in the context of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale” funded by the European Commission within the Horizon 2020 Programme (2014–2020, GA no. 635690).

Climate changes have a significant influence on rainfall quantity, on the loss of soil humidity and consequently loss of water in olive fruit. The loss of fruit moisture could result in dry olive paste during oil production, which makes extraction of olive oil difficult and could lead to lower oil yield. Addition of water during the malaxation process is suggested to overcome this problem, but this could cause a reduction of the phenolic compounds in obtained oil. The aim of this study was to investigate the effect of the addition of a small amount of water (5% w/w) in 'Leccino' cv. olive paste during malaxation on the oil yield, extractability index and oil phenolic profile. The intention was to investigate whether it was possible to achieve the benefit of improved oil extractability and at the same time preserve the major proportion of valuable phenolic compounds. The addition of 5% of water to the olive paste during malaxation had no influence on oil yield and extractability index. On the other hand, water addition caused an increase in the concentration of total secoiridoids and total flavonoids, while total simple phenolic compounds decreased. The obtained results pointed out that even if a small amount of water addition during malaxation had no significant influence on oil yield and extractability index, the resulting changes in oil phenolic profile indicated the possibility of a positive influence on its oxidative stability, and consequently extension of its shelf life.

Extra virgin olive oil (EVOO) is often used as a natural medium for the storage of different types of food, although its presence could modify the EVOO composition. Therefore, this study aimed to evaluate the influence of dry tomato addition on EVOO bioactive compounds (phenols and pigments) used as a storage medium. For that purpose, 15 g of dry tomatoes were placed in glass jars filled with Istarska bjelica EVOO (100 mL) and stored for one month at room temperature. The control samples, EVOO without dry tomatoes, were stored under the same conditions. The phenolic composition of the oils was determined by HPLCDAD, the antioxidant capacity was studied by evaluating the free radical-scavenging effect of DPPH radical while chlorophylls and carotenoids were determined spectrophotometrically. After storage, all the oil samples showed a reduction in secoiridoids and flavonoids concentration, consequently decreasing the total phenols and radicalscavenging activity of the oils. However, the decrease was more notable in oil samples stored with dry tomatoes. The chlorophyll and carotenoid concentration of the oils remained preserved. Obtained results indicate that the addition of dry tomato accelerated the oxidation of the phenolic compounds during storage, decreasing the virgin olive oils nutritional value. This work has been supported by the Croatian Science Foundation (DOK-2018-09-2293 and DOK-2018-01- 4693) and co-financed by the EU from the European Social Fund (DOK-2018-01-4693).

Virgin olive oils are exclusively extracted from olive fruits, but small amount of olive leaves are usually present during the fruit extraction. Since the olive leaf is an excellent source of phenols, in this study the effect of the olive leaves present during the Leccino cv. olive oil extraction on the phenolic compound composition and oxidative stability of the produced oils were investigated. For that purpose, olive fruits were extracted at the industrial scale without the leaf (control oil) and with the addition of Leccino cv. leaves (2.5% in relation to the total amount of olive fruits), in triplicate. In the oils, phenolic profiles using high performance liquid chromatography (HPLC-DAD) and oxidation stability index (OSI-time) evaluated as resistance to forced oxidation were determined. The leaf addition increased concentration of simple phenols, phenolic acids, flavonoids, and secoiridoids in the obtained oils, as well as oils’ oxidative stability index (about 20%). These results indicate that the olive leaf addition during olive oil production can be an effective way for producing enriched oil with natural antioxidants, thus improving nutritional properties and extending its shelf life. This work has been supported by the Croatian Science Foundation (DOK-2018-09-2293 and DOK-2018-01-4693) and co-financed by the EU from the European Social Fund (DOK- 2018-01-4693).

Djevičansko maslinovo ulje proizvod je od velike ekonomske važnosti za zemlje Mediterana, ali i za Hrvatsku. U zadnjem je desetljeću prisutan pozitivan globalni trend širenja proizvodnje i potrošnje maslinovog ulja u svijetu. Međutim, povećanje proizvodnje dovelo je do sve većeg nakupljana sekundarnih produkata proizvodnje (lišća masline, otpadnih voda i komine masline) koji ako se ne zbrinu na pouzdan način mogu dovesti do negativnog utjecaja na okoliš. Način zbrinjavanja određuje se prema količini i vrsti nastalih ostataka te nerijetko može predstavljati značajan financijski trošak za proizvođača. Proteklih godina učinjen je veliki napor znanstvene zajednice kako bi se pronašli održivi načini za učinkovito zbrinjavanje otpada nastalog proizvodnjom maslinovog ulja s pozitivnim komercijalnim ishodom. LCA metodologija (eng. Life Cycle Assessment – procjena životnog ciklusa) najčešće je korištena metoda za procjenu učinka proizvodnje djevičanskog maslinovog ulja na okoliš. Ponovno iskorištenje sekundarnih produkata proizvodnje maslinovog ulja u skladu je s globalnim ciljevima održivog razvoja i očuvanja okoliša. Kako bi maslinarstvo doprinijelo borbi protiv klimatskih promjena potrebno je da svi segmenti proizvodnje budu potpuno održivi, s minimalnom razinom otpada, radi stvaranja zatvorenog kruga proizvodnje. U ovom preglednom radu prikazane su nove strategije zbrinjavanja sekundarnih produkata proizvodnje maslinovog ulja s naglaskom na one koje uključuju izdvajanje ili biokonverziju biološki aktivnih spojeva. Ovaj je rad podržan od Hrvatske zaklade za znanost kao dio projekta „Projekt razvoja karijera mladih istraživača – izobrazba novih doktora znanosti” (DOK-2018-09-2293) te sufinanciranog od Hrvatske zaklade za znanost i Europske unije iz Europskog socijalnog fonda (DOK-2018-01-4693).

Preserving extra virgin olive oil (EVOO) chemical composition is essential to maintain its beneficial health effects, which are mostly attributed to the abundant phenolic content. Indeed, EFSA authorizes a health claim for olive oils that contain a minimum of 5 mg of phenols (hydroxytyrosol and its derivatives) per 20 g of oil, claiming them beneficial for the protection of blood lipids from oxidative stress. This study aimed to investigate the applicability of this claim during the EVOO domestic consumption. For that purpose, three dark glass bottles of Buža cultivar EVOO were stored for one month at 21 ± 3 °C. During this period, 20 mL of EVOO was withdrawn daily from each bottle, simulating domestic consumption. The phenolic content in oils was analysed after 0, 7, 21, and 28 days of storage using the HPLC-DAD system. The simple phenols content remained unchanged during this period. However, the secoiridoid, phenolic acid and lignan content decreased already after the first week, but after which the concentrations remained unchanged for the next three weeks. The same outcome was observed for the total identified phenolic content. Although the secoiridoids content decreased from day 0 to 28 by 21.05 %, it remained sufficient to satisfy the health claim. The obtained results indicated that Buža EVOO consumed within one month under optimal domestic conditions preserved its beneficial phenolic content. This work has been supported by the Croatian Science Foundation (DOK-2018- 09-2293 and DOK-2018-01-4693) and co-financed by the EU from the European Social Fund (DOK- 2018-01-4693).

This study aimed to evaluate changes in the quality parameters and phenolic compounds profile, determined by HPLC-DAD, after a 6-month storage period of Istarska bjelica and Buža cv. virgin olive oil. Obtained results showed diverse susceptibility to oxidative degradation in the two investigated monovarietal olive oils. Istarska bjelica virgin olive oil preserved its phenol content during the storage period, while there was a slight decrease in Buža secoiridoid content. Based on the obtained results it can be concluded that the oxidative stability and evolution of phenolic compounds in virgin olive oil are dependent on the initial phenolic composition of the selected olive cultivar.

The Panel Test method for the organoleptic assessment of virgin olive oils classifies oils into quality categories on the basis of the intensity of predominant defect and fruity attribute. The setting up of artificial and reproducible reference materials (RMs) is one of the objectives of the OLEUM project in order to increase the proficiency of the sensory panels involved in the Panel Test. In this context, two new RMs, for the aroma of winey-vinegary and rancid defects, have been formulated by adding specific volatiles responsible for negative sensory attributes to the refined olive oil. In this study, newly-designed artificial RMs were assessed by six panels to evaluate their i) representativeness, ii) panel detection thresholds, and iii) shelf-life after 3 and 6 months of storage. Both of the tested RMs were considered representative of the related defects. The panels’ detection threshold for the winey-vinegary and rancid defect corresponded to a perceived intensity between 0.3 and 1.0, and 0.3 and 1.1, respectively. Considering the shelf life, there were no significant differences in the evaluation of winey-vinegary RM during the storage, although, in the case of rancid RM, there was a clear intensity increase with time. The utilization of artificial RMs could improve the method effectiveness by offering advantages such as reproducibility and unlimited availability.

The aim of this study was to investigate two strategies for the improvement of the antioxidant content of Buža cv. virgin olive oil: (i) leaf addition (2.5%) during oil extraction and (ii) prolongation of malaxation duration (from 30 to 45 min). The results showed that the addition of leaves increased the content of pigments in oil, while the total phenolic content slightly decreased. Extended malaxation increased the content of pigments, main groups of phenols, and total phenols. Both strategies could be potentially applied for the antioxidant enrichment of Buža cv. virgin olive oil, but the extended malaxation duration improved its nutritional value in a higher degree.

Kako bi se proizvelo ekstra djevičansko maslinovo ulje visoke kvalitete preporuča se preraditi plodove masline neposredno nakon berbe. Zbog relativno kratkog razdoblja berbe maslina u Hrvatskoj i ograničenog kapaciteta uljara, ponekad je prije proizvodnje ulja masline potrebno kratkotrajno uskladištiti. Klimatske promjene utječu na više prosječne temperature tijekom berbe i skladištenja plodova maslina, što ubrzava kvarenje maslina i smanjuje kvalitetu dobivenog maslinovog ulja. Stoga je cilj ovog istraživanja bio ispitati mogućnosti produljenja razdoblja skladištenja plodova maslina primjenom niskih temperatura skladištenja bez ugrožavanja kvalitete maslinovog ulja. Kako bi se istražio utjecaj niskih temperatura skladištenja maslina na fenolni sastav i senzorske karakteristike djevičanskog maslinovog ulja sorte Rosinjola, plodovi maslina pobrani su i prije proizvodnje čuvani 7 dana na tri različite temperature: sobna temperatura (RT), +4 °C i -20 °C. Koncentracija ukupnih fenola snizila se samo u uzorcima skladištenim na -20 °C, dok se koncentracija sekoiridoida snizila nakon skladištenja na RT i -20 °C. Senzorna kvaliteta ulja očuvana je samo nakon skladištenja na +4 °C, dok su se u ostala dva tretmana u ulju pojavile mane: vinski-octikavo (na sobnoj temperaturi) i smrznute masline (na -20 °C). Dobiveni rezultati ukazuju na mogućnost proizvodnje visokokvalitetnog maslinovog ulja nakon dužeg skladištenja na temperaturi od +4 °C, što može biti korisno za pravilno upravljanje skladištenjem plodova nakon berbe, posebno u sezonama kada su kapaciteti berbe veći od kapaciteta prerade. Ovaj je rad djelomično financiran od strane Hrvatske zaklade za znanost u okviru projekata UIP-2014- 09-1194, DOK-2018-09-2293 te projekta DOK-2018- 01-4693, koji je sufinancirala i EU iz Europskog socijalnog fonda.

Klimatske promjene imaju značajan utjecaj na količinu oborina što utječe na gubitak vlažnosti tla, a samim time i na gubitak udjela vode u plodu masline. Gubitak vode u plodu može dovesti do pojave suhog tijesta masline tijekom proizvodnje ulja, što otežava ekstrakciju ulja i može dovesti do gubitka u prinosu maslinovog ulja. Stoga je cilj ovog istraživanja bio ispitati utjecaj dodatka vode (40 mL) u tijesto maslina (800 g) tijekom proizvodnje ulja sorte Leccino u laboratorijskim uvjetima na proizvodne parametre (prinos ulja i indeks ekstraktabilnosti) i na sastav fenolnih spojeva određenih HPLC-DAD analizom. Dodatak vode u tijesto maslina tijekom procesa malaksacije nije imao značajan utjecaj na prinos i indeks ekstraktabilnosti ulja. Međutim, dodatak vode imao je utjecaj na povišenje koncentracije najzastupljenijeg sekoiridoida 3, 4-DHPEA-EDA što je utjecalo na povišenje koncentracije ukupnih sekoiridoida, iako se koncentracija pojedinih sekoiridoida (oleuropein i ligstrozid aglikoni (izomeri I i II), oleuropein aglikon (izomer II)) snizila. Dodatak vode tijekom malaksacije uzrokovao je i porast koncentracije ukupnih flavonoida, dok se koncentracija ukupnih jednostavnih fenola snizila. Dobiveni rezultati pokazali su da, iako dodatak vode tijekom malaksacije nije imao značajan utjecaj na prinos ulja i indeks ekstraktabilnosti ulja sorte Leccino, nastale promjene fenolnog profila ulja ukazuju na mogućnost povećanja oksidativne stabilnosti ulja, što bi kao posljedicu moglo imati produljenje njegovog roka trajnosti. Ovaj rad dijelom financira Hrvatska zaklada za znanost u sklopu realizacije projekata DOK-2018-09-2293 i projekta DOK2018-01-4693, koji je sufinanciran i od strane Europska unija iz Europskog socijalnog fonda.

Traditional preparation of meals in Mediterranean countries, as well as in Croatia, includes oven roasting of meat, fish and vegetables with extra virgin olive oil (EVOO). Considering that, the main aim of this study was to determine changes in phenolic composition and antioxidant capacity in Istarska bjelica cv. EVOO after thermal treatment at different temperatures. Istarska bjelica was chosen for this purpose, as the most commonly used autochthonous cultivar whose oil is characterized by a high phenolic content. Istarska bjelica oil samples were heated at 180 °C and 220 °C in an oven for one hour, fresh oil was used as a control. Quality parameters, peroxide value (PV) and spectrophotometric indices (K232, K270 and ΔK), were determined according to the analytical methods described in the European Commission Regulation (EEC, 1991). The HPLC-DAD system was used for phenol content analysis. Antioxidant capacity was determined spectrophotometrically by evaluating the free radical-scavenging effect of DPPH radical. PV reduced at 180 °C, but maintained unchanged at 220 °C. Differently, a higher increase in K value parameters was observed with temperature alteration. This might have occurred as a result of highly unstable primary oxidation products who, due to enhanced oxidation, converted into secondary products. Total phenol and secoiridoid content decreased significantly only at 220 °C. Regarding individual phenols, most of them decreased at 220 °C, except in the cases of p-HPEA-EDA and hydroxytyrosol acetate whose concentration increased. Antioxidant capacity correlated with total phenol content showing a major decrease at 220 °C. Obtained results demonstrated that lower cooking temperatures (about 180 °C) have no significant negative effect on Istarska bjelica cv. EVOO total phenolic composition, as well as on its antioxidant capacity. Acknowledgement: This work has been supported in part by Croatian Science Foundation under the project “Young researchers' career development project – training of new doctoral students”, DOK-2018-09-2293.

Buža cv. virgin olive oil (VOO) obtained from fruits in advanced ripening stage has a low level of phenolic compounds and consequently, low oxidative stability and short shelf life. Olive leaves are a natural source of antioxidants, but are usually removed from olive fruits before the processing of VOO. In this study, the strategy for the enrichment of olive oil with leaf phenolic compounds and pigments, as well as the effect of leaf addition during the VOO extraction on the sensory quality of Buža oil is examined. For that purpose, Buža cv. olive fruits, in the advanced stage of ripeness (RI = 4.04), were harvested and the fresh leaves of the same cultivar at different rates (0% - control and 1, 2.5 and 5%) were added prior to oil extraction by a laboratory scale olive mill. Phenolic composition was determined using an HPLC-DAD system, pigments were determined spectrophotometrically and sensory analysis was performed by Panel test. Total phenols did not change significantly, although changes in concentration of some individual phenols were observed. Hydroxytryrosol had the highest concentration in the oils with 5% leaf addition, while the other three phenols (vanilic acid, oleuropein – ligstroside aglycones I, II and oleuropein aglycone (isomer II)) had the highest concentrations in the oils without leaf addition. The increasing rate of leaf addition during oil extraction induced an increase in chlorophyll and carotenoid content in obtained oils. Olive leaves addition did not affect the sensory total score and all investigated olive oil samples corresponded to the extra virgin category, but difference in particular sensory characteristics with increasing of olive leaves addition rate were observed: slightly higher intensity of olive fruitiness, aromatic herbs as well as intensity of astringency. Obtained results indicate that leaf addition up to 5% has no negative influence on Buža oil sensory characteristics, as well as on the content of total phenolic compounds, but increases oil pigment content. Further study, which investigates the oxidative stability and shelf life of Buža olive oil produced by addition of olive leaves, is needed. Acknowledgement: The work has been supported in part by the „Young researchers’ career development project – training of doctoral students“ (DOK-2018-01-4693) funded by the Croatian Science Foundation and the European Union from the European Social Fund.

Beneficial properties of polyphenols are widely recognized, and one of the food that stands out due to its content is the olive oil. However, over the past decade, the interest is raising for olive leaves as well. In particular, this may be interesting in biological waste management in the olive oil production process. Previous studies on olive leafs confirmed a high phenolic content that explain previously known strong antibacterial, antimicrobial and antiviral activity. Due to these findings, the major aim of our work was to determine the potential of olive leaves from cv. Buža, Istarska Bjelica and Leccino, as a natural source of bioactive compounds suitable for daily consumption in the form of tea. For this purpose, we examine the influence of olive leaf variety, maceration time and temperature on the tea phenolic composition. Phenolic compounds were analyzed by use of liquid chromatography coupled to triple quadrupole mass spectrometer (LC-QQQ). Results expectedly revealed significant influence of the olive variety but also maceration parameters on the quantitative and qualitative phenolic composition. The highest amount of phenolic compounds was obtained for Istarska Bjelica after maceration for 15 min. However, olive leaf tea from Buža had the most diverse phenolic composition. Furthermore, we simulated seven functional olive leaf teas with desired phenolic composition by using Design-Expert software (v11, Stat-Ease, Inc., Minneapolis, USA). Results confirmed the hypothesis on improved quality of different mixtures by means of an optimized phenolic composition.

Poznato je da fenoli maslinovog ulja imaju širok raspon pozitivnog djelovanja, ali je manje poznato da se te blagotvorne komponente nalaze i u ostalim dijelovima stabla masline. Upravo stoga, ovaj je rad usmjeren na analizu lišća maslina. Nedavna istraživanja sastava maslinovog lišća pokazala su kako se u lišću masline nalazi visoka količina polifenola, čime se može objasniti prethodno poznata antibakterijska, antivirusna i antimikrobna aktivnost. Cilj diplomskog rada bio je utvrđivanje potencijala lišća sorti masline Buža, Istarska Bjelica i Leccino, kao prirodnog izvora polifenola pogodnih za svakodnevnu konzumaciju u obliku čaja. Specifično se pratio utjecaj sorte masline, vremena i temperature maceracije na sadržaj polifenola. Na temelju dobivenih rezultata provedena je optimizacija pripreme čaja. Razina uspješnosti optimizirane metode utvrđena je s organskom ekstrakcijom u metanolu. Analiza polifenolnog sadržaja provedena je na masenom spektrometru s trostrukim kvadropolom (LC-QQQ). Naposljetku, uz pomoć Design-Expert softvera dizajnirane su mješavine čaja na temelju željenog sastava polifenola. Rezultati su pokazali utjecaj sorte masline i načina pripreme na kvantitativni i kvalitativni sastav polifenola. Najviša količina ukupnih fenola pronađena je u uzorcima čaja Istarske bjelice u čijoj se pripremi koristila kipuća voda, uz maceraciju od 15 min. Uzorci sorti Buža i Leccino, iako su sadržavali manje ukupne količine polifenola, istaknuli su se po raznolikosti polifenolnog sastava. Ovim radom dobili smo važne spoznaje o utjecaju sorte masline na kvantitativni i kvalitativni fenolni sastav. Opis monosortnih uzoraka čaja omogućuje daljnji razvoj funkcionalnog čaja s blagotvorinim učincima na zdravlje.

Fenoli su bioaktivni spojevi koji pripadaju skupini fitokemikalija.