Journal on Processing and Energy in Agriculture 23 (2019) 4 199 Biblid: 1821-4487 (2019) 23; 4; p 199-201 Original Scientific Paper UDK: 547.979.7 Originalni naučni rad DETERMINATION OF THE CHLOROPHYLL CONTENT OF PISTACHIO (Pistacia vera L.) KERNELS USING VARIOUS EXTRACTION TECHNIQUES ODREĐIVANJE SADRŽAJA HLOROFILA U JEZGRU PISTAĆIJA (PISTACIA VERA L.) KORIŠĆENJEM RAZLIČITIH TEHNIKA EKSTRAKCIJE Gözde NOGAY, Şule Hilal ATTAR, Leyla GUNDUZ, M.Salih KAFKAS, Ebru KAFKAS, Harun KARCI University of Çukurova, Faculty of Agriculture, Department of Horticulture, 01330, Balcalı, Adana, TURKEY e-mail: ebruyasakafkas@gmail.com ABSTRACT The pistachio (Pistacia vera L.), a small nut tree belonging to the Anacardiaceae family, is extensively grown in Turkey, which is one of the leading world producers of pistachios. Kernel color is an important parameter for the evaluation of raw pistachios containing chlorophylls a and b as the major pigments. Moreover, kernel color is one of the most important quality attributes evaluated by consumers, producers and distributors. Chlorophylls a and b are the predominant pigments responsible for the green color of pistachios. Pigment concentrations are influenced by a number of factors such as geographic origin, ripeness degree, storage conditions and processing methods. Chlorophylls are sensitive to heat and can be degraded into pheophytins and pyropheophytins. Therefore, the purpose of this paper is to determine the chlorophyll content of the ‘Uzun’ pistachio cultivar (Pistacia vera L.) using the spectrophotometric methods and different solvents. Keywords: pistachio, chlorophyll a, chlorophyll b, spectrophotometry REZIME Koštičavo voće Pistacia vera L. član je porodice Anacardiaceae, uzgaja u Turskoj, koja je jedan od vodećih svetskih proizvođača. Boja jezgre je važan parametar za procenu pistaćija, a ona je definisana prisustvom hlorofila a i hlorofila b, kao najvažnijim pigmentima u sirovim pistacijama. Pored toga, boja je jedan od najvažnijih atributa kvaliteta koji ocenjuju potrošači, proizvođači i distributeri. Hlorofil a i b su pretežni pigmenti odgovorni za zelenu boju pistacija. Na koncentraciju pigmenta utiče niz faktora, uključujući geografsko poreklo, stepen zrelosti, uslovi skladištenja i metode prerade. Hlorofili su toplotno labilni i mogu se razgraditi da bi formirali feofite i pirofeofite. Zbog toga, cilj je bio da se utvrdi sadržaj hlorofila u pistaćiju sorte Uzun (Pistacia vera L.) korišćenjem različitih rastvarača za spektrofotometrijske metode u ovoj studiji. Prema dobijenim rezultatima, vrednosti hlorofila u različitim korišćenim rastvaračima imali su različite rezultate. Najveća vrednost postignuta rastvorom „aceton sa 1% HCl“ korišćenim za hlorofil a i hlorofil b, a za uzorke brašno jezgra i ulja od uzoraka pistaćija. Sa druge strane, najvića vrednost hlorofila a i b dobijne su kada je brašno jezgre korišćeno kao ekstrakcioni materijal. Ključne reči: pistaći, hlorofil a, hlorofil b, spektrofotometrija. INTRODUCTION The pistachio (Pistacia vera L.) is one of the most popular nut crops worldwide. It is extensively cultivated in arid regions of the world owing to its ability to sustain hot and dry weather. Pistachios contain significant compounds beneficial to human health, which foster their global production (Ukhanova, et al., 2014). Iran, Turkey, USA, Syria, Italy, Tunisia and Greece are the main producers of pistachios in the world, growing various pistachio cultivars adapted to different environment conditions. Pistachio nuts have green or yellow kernels, characterized by the alternate bearing phenomena (Monastra et al., 1987), which ultimately determine their taste. Owing to its appreciable qualities such as shape, size, aroma and green color in particular (especially in hulled and peel-backed products), the pistachio is used as an ingredient in pastries, hams, salamis, ice creams, sweets and chocolates (Angelini, 1987). From a nutritional perspective, the energy value of pistachios is similar to almonds (2332 kJ/100 g). They are also rich in carbohydrates and minerals, mainly potassium (1025 mg/100 g) (USDA SR 18, 2005). The fat content of pistachios is about 50–70 % of the total nut weight relative to the variety. Carbohydrate formation occurs in chlorophyll facilitated by light energy in photosynthetic organisms. Chlorophylls play a vital factor in photosynthesis. The most active pigments involved in photosynthesis are chlorophylls, i.e. the green pigments of plants. Plants can be stressed by negative changes in chlorophyll contents. Therefore, the chlorophyll content of the plant is very important for the accumulation of carbohydrates (Genty et al., 1989). Genotype, environmental conditions, early harvest date and selection of rootstocks have significant effects on kernel color (Kunter et al., 1995). Chlorophylls a and b are found in higher plants. Chlorophyll a has a blue-green color, whereas chlorophyll b features a yellow-green color. In general, chlorophylls a and b are present in equal proportions, but the a/b ratio can vary and is affected by sunlight. During maturation, the color of pistachio kernels turns from green to yellowish green (Anderson, 1986). However, there are many studies on the nutrient content of pistachios. For instance, Lutovska et al. (2014) researched the nutritive values of pistachios, almonds, soybeans and cereals. However, there are no studies on the variation in or the comparison between kernel and kernel oil chlorophyll contents of pistachio cultivars. The purpose of this study is to determine variations in the kernel chlorophyll content of the ’Uzun’ pistachio cultivar using different extraction solvents. MATERIAL AND METHOD Material Oil and kernel samples of the ‘Uzun’ pistachio cultivar were used as experimental materials in the present study. The ‘Uzun’ pistachio cultivar is a mid-season cultivar yielding pistachio fruits of medium quality. However, this cultivar produces higher yields than the ‘Halebi’ and “Kırmızı” cultivars. Notwithstanding its small size, ‘Uzun’ is globally known for its