STUDY OF KALINJOTI EXTRA VIRGIN OLIVE OILS, FATTY ACIDS PROFILES AND TRANS-ISOMERS

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1 STUDY OF KALINJOTI EXTRA VIRGIN OLIVE OILS, FATTY ACIDS PROFILES AND TRANS-ISOMERS Stela Velo 1*, Dritan Topi 2 1 Department of Industrial Chemistry, Faculty of Natural Sciences, University of Tirana, Blv. Zogu 1, No 25, Tirana, 1009, Albania 2 Department of Chemistry, Faculty of Natural Sciences, University of Tirana, Blv. Zogu 1, No 25, Tirana, 1009, Albania * stelavelo@hotmail.com Original scientific paper UDC (496.5) Abstract In the recent years growing interest is shown in the fatty foods quality. In that group a notable interest is shown for olive oil. Evaluation of quality for that commodity group mainly is focused in the group of quality tests: acidity (Free fatty acids - FFA), K 270, stability index, peroxide value (PV), etc., by preventing their adulteration of products launched in the retail market. Notably of high importance is their control for main constituents, and traceability of the product of origin as a mean to increase the economic revenues through the production of Product of designation of origin (PDO). Having this in mind we performed analysis on the fatty acid (FA) profiles of fats and oils and minor constituents. This aspect is linked also with health issues. Kalinjoti is main autochthonous olive cultivar in Albania, covering more than 55% of total olive plantations. Its main areal are the south-western regions of Vlora and Mallakastra, and during last 50 years was introduced in other regions of the country, toward the northern latitudes, or in: Lushnja, Kavaja, and Vora. Twelve samples of mono cultivar olive oils were collected from Vlora and Mallakastra region and Kavaja-Vora region, aiming to give indication of the origin of product through fatty acid (FA) profiles studying. The samples were characterized for their FA profiles by Gas chromatography-flame ionization detector - GC/FID and Gas chromatography - mass spectrometry GC/MS. Fatty acid profiles of all olive oil samples revealed the presence of 17 FA, including the trans-isomers. Oleic acid content varied from 73.65% to 76.15%. The content of palmitic acid was relatively low or from 8.82% to 11.09%. The levels of linoleic acid resulted from 8.15% to 9.31%. Linolenic acid varied from 0.70% to 0.86%, or lower than 1%. The sum of trans-fa resulted as under 0.05%. Analytical data give indication that the Olive Oils based on their fatty acid profile are similar to FA from other olive cultivars of neighboring countries on the same latitude. They were found rich in mono unsaturated fatty acids (MUFA), and low in saturated fatty acid (SFA). Their FA profiles were found not significantly linked with their brand name. The distribution of trans- FAs was below the threshold established by Commission Regulation 1989/2003 amending EU Regulation 2568/91 [14]. Key words:kalinjoti, Olive oil, Fatty acids, Trans-fatty acid, Albania. 1. Introduction Olea europaea, is one of the most important fruit trees in Mediterranean countries, where they cover ~8 million ha, accounting for almost 98% of the world crop (Taberq et al., [19], Bouaziz et al., [3]). Its product, olive oil, is a product of great importance due to its nutritional value, which is acknowledged internationally (Christopoulou et al., [1]). Olive production is a leading industry for rural semi-arid areas of the Mediterranean basin countries, and contributes to local economic development of these communities. Albania, situated in northern coast of Mediterranean Sea, in the western part of Balkan Peninsula, has the favorable climatic and geographical conditions for olive tree cultivation. The production capacity is increased considerably during last year s from about 70,000 tons of olives/year and about 7,800 tons of olive oil to 125,000 tons in 2013 (FAO, [7]). The olive groves occupy 41,000 ha with 5,011 million productive olive trees spread in approximately 118,000 small farms/0.4 ha [17]. Regions that have cultivate this cultivar are: Vlora (36.1%), Fieri (17.3%), Berati (16.4%), Tirana (11%), and Elbasan (7%) and in less extent in northern regions of 129

2 the country, Lezha and Shkodra (Figure 1). Olive culture contributes positively to the landscape and natural values of the regions where it is cultivated. They are planted in the ground and carry steep erosion protection functions. Albania is rich with more than 28 varieties grown throughout the country. Albanian autochthon olive cultivarsare Kalinjoti, Kallmet, white olive of Kruja, white olive of Tirana, Frëngu, etc. The two leaders are Kalinjoti, which covers about 50% of the total plantations for oil and table use; and Kokërmadh Berati, representing approximately 20% of table olives (Kafazi and Muço, [5]; Osmani, [6]; Ismaili [4]). methodology to differentiate these products according to their cultivar and geographical origin (Aparicio and Luna, [8]; Mannina et al., [9]). In this study are analyzed the fatty acid composition and trans-isomers of two same olive cultivars but in different region: Kalinjoti of Vlora and Kalinjoti of Mallakastra. 1.1 Kalinjoti cultivar The most important part of the production capacity is composed by Kalinjoti variety, which presents the main level of production at the national level, which constitutes over 70% of the structure of Vlora region. The Kalinjoti (Figure 2) is a traditional variety in many region of Albania. It is one of the most outstanding cultivar for the production of olive oil, with good resistance adaptable to different climates and soils. Figure 2. Structure of the Albanian groves cultivations Figure 1. Distribution of oil production according varieties in the area of olive growing (Source: Olive strategy, MAFCP 2010, personal calculations [24]) The interaction of the Albanian varieties with the local environment (soil, climate, altitude) and cultural practices results in the special characteristics and tastes distinctive to the oils produced in various regions of throughout Albania. The chemical and physical characteristics of olive are strongly dependent on the: cultivar, habitat and geographical area (Bianco et al., [2]). In particular, they influence the quality of olive and are related to the subspecies considered, the age of the plant, the characteristic of cultivation, of climate, of habitat and general geographical area, and inorganic and organic components present in the oil. Publications on the chemical composition for olive oils from Albanian cultivars are presented only recently (Topi et al., [18]). The characterization of fatty acid profiles of olive oils from different olive cultivars is usually proposed as a Type of protection: PDO Geographical area: Kanina (nearby the city of Vlora) and Tre vllazer (area in the hills of Novosele municipality, Vlora) Varieties: the main cultivars used in these area is Kalinjoti ; in the same area are also cultivated other international varieties, such as Frantoio. The Kalinjoti cultivar is native of the Vlora and Mallakastra regions, principally on the Ionian Sea. The Kalinjoti cultivar is planted with another olive cultivar, the Pulazeqin, which is doing the pollination. This technique allows a better yield of the Kalinjoti. The weight of the fruit is 3.64 grams and the weight of the stone is 0.49 grams. The percentage of oil which can be extracted from the olive is 28%. The productivity of the cultivar is good. This variety is relatively resilient to drought and cold weather. Production method: Every part of the process of growing, preparing and packing the olives takes place within the defined geographical area. In this area are also located some high quality oil mills. 2. Materials and Methods 2.1 Materials Twelve samples of mono cultivar olive oils of were collected from Vlora and Mallakastra region and Kavaja-Vora region, aiming to give indication of the origin of product 130

3 through studying fatty acid (FA) profiles. The samples were characterized for their FA profiles by a lot of methods and limits, which were introduced into the International Olive Oil Council (IOOC) trade standards [21], into EC Regulation 2568/91, [13], and into the Codex Alimentarius Standard, [22], for controlling product authenticity and quality (Bianchi et al., [25]). The conditions for the analysis were: solvent: acetone/ acetonitrile 50:50 v/v, flow rate 1.5 ml/min., oven temperature 42 0 C. 2.2 Methods Fatty acid methyl esters (FAME) were prepared through direct acidic transesterification, as originally proposed by Lepage and Roy [10] and later modified by Carvalho and Malcata [11], using pentadecanoic acid (C 15:0) as internal standard. The assay of FAME was carried out with a HP-6890 Gas chromatograph, equipped with a Flame Ionization Detector (GC-FID). Separation was achieved in a SP-2380 capillary column (60 m 0.32 mm 0.20 µm). Hydrogen was used as carrier gas at a flow rate of 1.0 ml/min. The temperatures in the injector and detector were C and C, respectively. The injection was performed in split mode (1 : 50). Oven temperature was set to C for 18 min. increased to C at a rate of 1 0 C/min. and held at C for min. Calculations were performed according to AOCS Official Method Ce 1b-89 [12], and by the computer program according the EC Regulation 2568/91 method [13]. 3. Results and Discussion The value of free acidity of the samples of monovariety extra virgin olive oils proved the good quality of the analyzed oils. Table reports the percentage of fatty acids in monovariety oils from cultivar Kalinjoti in region of Vlora and Mallakastra and confirm their similar. Fatty acid composition of all the analyzed monovariety oils meets the limits set for extra virgin olive oil (EC Regulation, [13]), because fatty acid composition is used only for the evaluation of oil purity, which is guaranteed by establishing the maximum content of some minor fatty acids. Fatty acid (FA) profile and contents Kalinjoti cultivars of Vlora s and Mallakastra s regions are displayed in Table 1 and Figure 3. Thirteen different FA were found for both oil. In order of abundance, the most important ones were: oleic acid (18 : 1), palmitic acid (16 : 0), linoleic acid (18 : 2), linolenic acid (18 : 3). Chemical diversity of oil composition for olive may be attributed to the climatic, geographic, genetic and other factors. Many factors affect secondary metabolites in olive oil, such as cultivars, ripening scale, seasonal variation, and light climate in addition to the climatic, geographic, genetic or their combination. Table 1. Fatty acid profile (in% of total FA), n-6/n-3 and 18:1/18:2 ration of the Kalinjoti Cultivar Chemical formula Kalinjoti (Mallakastra) Kalinjoti (Vlora) CODEX STAN [25] C14: C16: C16:1(n-7) C17: C17:1(n-7) C18: C18:1(n-9) C18:2(n-6) C18:3(n-3) C20: C20:1(n-9) C22: C24: SFA * MUFA * PUFA * n-6/n :1/18: MUFA/SFA MUFA/PUFA Trans fatty acid C18:1T C18:2T+C18:3T *SFA = Saturated Fatty Acids, MUFA = Monounsaturated Fatty Acids, PUFA = Polyunsaturated Fatty Acids Figure 3. Levels in fatty acids % of Kalinjoti cultivar in different region of Albania Comparison of the FA profiles of the same cultivar but in different region of Albania: oleic acid (OA) (Figure 4) content was: 76.15% (Kalinjoti of Mallakastra) and 75.51% (Kalinjoti of Vlora); linoleic acid (LA) (Figure 5) content was: 9.31% for Kalinjoti of Mallakastra and 8.15% for Kalinjoti of Vlora. These results show that there is no big difference between the same cultivar although it is cultivated in different regions of Albania. The difference between the two oils is very small, maybe as a result of the climatic, geographic, genetic and other factors. 131

4 Figure 4. Oleic acid levels All the values of fatty acids are almost in conformity to those of International Olive Oil Council s regulation (IOOC, [21]) and Codex Alimentarius [22]. A high content of alpha-linolenic acid (ALA) contributes to the n-6/n-3 ratio, a very important value for the nutritional evaluation of lipids of different origin. Regarding such ratio, the Kalinjoti cultivar show an n-6/n-3 ratio of , where in Kalinjoti of Mallakastra and in Kalinjoti of Vlora. Analysis of the ratio 18:1/18:2 is an indication that refers to the oil oxidation stability. The lowest value proposed is 18:1/18:2 7 (Kiritsakis et al., [16], and [20]). The results show that the monovariety olive oils from (Kalinjoti of Mallakastra) and (Kalinjoti of Vlora) have acceptable oxidation stability. Analysis the value for the three families of fatty acids Saturated Fatty Acids (SFA), Mono unsaturated Fatty Acids (MUFA), and Polyunsaturated Fatty Acids (PUFA), results that olive oil from the Mallakastra Kalinjoti cultivar has high levels of MUFA (77.23) and PUFA (10.17) while Kalinjoti olive oil from Vlora has higher levels of SFA (14.4). The obtained data showed that there were significant differences between Kalinjoti and Ulliri i bardhe Tirana (UBT) (Topi et al., [18]). The highest fatty acid content was observed for Kalinjoti cultivar and the lowest fatty acid content was observed for UBL cultivar, for example: the oleic acid (OA) content: % (Kalinjoti) and ±0.039% (UBL); the linoleic acid (LA) content: % (Kalinjoti) and ± 0.003% (UBT). The Kalinjoti cultivar show an n-6/n-3 ratio of and UBT show an n-6/n-3 ratio of The Kalinjoti cultivar result with more acceptable oxidation stability compared to UBT cultivar, because the analysis of the ratio 18:1/18: 2 show (Kalinjoti) and 8.15 (UBT). The trans-isomer fatty acid in an olive oil from the both region is similar with a little difference, result a value from 0.01% to 0.02% and in the sum of trans-linoleic acid isomers in the same maximum value of 0.01% to The sum of trans-fa resulted under 0.05%. Figure 5. Linoleic acid levels Comparison of the FA profiles of the olive oil from Albanian native cultivar (Kalinjoti) with those in neighboring countries: Italy, Greece (Aparicio and Luna [8]; Pinelliet al., [14]; Paz Aguilera et al., [15]) and Northern Africa (Haddada et al., [23]) gives indication that it is comparable with Italian and Greek olive cultivars (Paz Aguilera, et al., [15]). For example, the level of palmitic acid in the studied native cultivar (Kalinjoti of Albania %) is comparable with Italian cultivars Leccino (14.3%) and Moraiolo (10.5%); Spanish cultivars Arbequina (14.3%); Lechin (10.5%) and Redondilla (12.5%), and Greek cultivar Koreiniki (13.3%). The level of oleic acid in Albanian cultivar ( %) is comparable with Frantoio (78.2%), Arbequina (75.3%) and Koreiniki (71.9%) (Aparicio and Luna, [8]). 4. Conclusions - Basing on the results of the study, we can say that cultivar Kalinjoti presents high variability in composition, comparable to that of the Mediterranean countries, as well as other native cultivars in Albania. - It presents qualitative and balanced profile of fatty acids, which the levels of the fatty acids are almost in conformity to those of International Olive Oil Council s regulation (IOOC, [21]) and Codex Alimentarius [22], so we may conclude that production of the mono variety olive oil from Kalinjoti cultivar is in accordance with quality characteristics drawn by EU Regulation 1989/ It represents an interest in producing a quality olive oil. Basing in the comparison with results from literature, it can be concluded that the levels of fatty acids in the oils of Kalinjoti cultivar are almost similar to those in neighboring countries: Italy, Greece, and Spain. The nutritional profile of Kalinjoti cultivar is highly interesting, as well as the UBT olive cultivar, due to its fatty acid content, n-6/n-3 ratio and 18:1/18:2 ratio. 132

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