Physico-chemical characteristics of juice extracted by blender and mechanical press from pomegranate cultivars grown in Georgia Dhivyalakshmi Rajasekar a , Casimir C. Akoh a,⇑ , Karina G. Martino a , Daniel D. MacLean b a Department of Food Science and Technology, University of Georgia, Athens, GA 30602-2610, United States b Department of Horticulture, University of Georgia, Tifton, GA 31793-5766, United States article info Article history: Received 10 October 2011 Received in revised form 5 December 2011 Accepted 2 February 2012 Available online 14 February 2012 Keywords: Aril juice Extraction methods Yield Antioxidant capacity Total phenolics Anthocyanins Titratable acidity abstract Pomegranate juice is consumed widely for its possible health benefits. The aril juice from 15 pomegran- ate cultivars grown in Georgia were analysed for juice yield based on fresh weight (FW) and physico- chemical properties, using blender and mechanical press extraction. Blender had a higher juice yield (42.04% FW) compared to mechanical press (38.05% FW). Total phenolics and antioxidant capacity was determined by Folin–Ciocalteau method and ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and oxygen radical absorbance capacity (ORAC) assays, respectively. Total monomeric anthocyanins were determined by pH differential method and RP-HPLC. The major anthocy- anin was delphinidin 3-glucoside. High negative and significant (p 6 0.05) correlations were found between pH and titratable acidity (TA). The total soluble solids content (TSS) averaged 15.59 in blender and 14.94 °Brix in mechanical press. Chemical analysis of juice showed significant differences among cul- tivars and extraction methods. Overall, blender was more efficient than mechanical press juice extraction. Ó 2012 Published by Elsevier Ltd. 1. Introduction The pomegranate (Punica granatum L.) fruit has been exten- sively used in folk medicine and is gaining popularity in recent times, mainly due to its possible health benefits. These benefits may be attributed to the polyphenols which possess antioxidant activities and influence colour, flavour, and texture (Poyrazog ˘lu, Gökmen, & Arti 9 k, 2002). The juice consists of antioxidative pheno- lics like punicalagins, hydrolyzable tannins, anthocyanins and ella- gic acids (Gil, Hess-Pierce, Holcraft, & Kader, 2000). Numerous studies suggest that these phenolic compounds can be used for the prevention and treatment of diseases like cancer and chronic inflammation (Lansky & Newman, 2007). Seeram et al. (2008) re- ported that the antioxidant activity of pomegranate juice is greater than other fruit juices and beverages. Pomegranate fruit has been widely grown in Iran, Turkey, India, China, Afghanistan, Russia, and United States (Lansky & Newman, 2007). The edible fruit part is the arils which are consumed fresh or as processed products, predominantly as juice. The pomegranate juice contains six anthocyanin pigments namely 3-mono- and 3,5- diglucosides of cyanidin, delphinidin, and pelargonidin, which are primarily from the arils and responsible for the intense red colour (Alighourchi, Barzegar, & Abbasi, 2008; Miguel, Dandlen, Antunes, Neves, & Martins, 2004). The evaluation of phenolic compounds and juice characteristics is essential to satisfy current market demands for quality fruit and for its potential use as a functional nutraceutical beverage. Studies have shown cultivar’s significant influence on antioxidant activity and physicochemical properties like juice yield, pH, total soluble solids (TSS), titratable acidity (TA), total phenolics, and anthocyanins (Mousavinejad, Emam- Djomeh, Rezaei, & Haddad Khodaparast, 2009; Ozkan, 2002; Özgen, Durgaç, Serçe, & Kaya, 2008). The level of anthocyanin in the fruit depends on various factors, namely: species, varieties, growing conditions, seasonal variations, maturity index, processing methods, and storage conditions (Melgarejo, Salazar, & Artes, 2000; Ozkan, 2002). The effect of two different pomegranate juice extraction methods on anthocya- nin stability was studied by Miguel et al. (2004). Gil et al. (2000) reported that the juice obtained from arils alone had lower antiox- idant capacity than commercial juice obtained from whole fruit. The purpose of this study was to evaluate and compare the juice yielding potential, antioxidant capacity, total polyphenols, total and individual anthocyanin levels of 15 pomegranate cultivars grown in Georgia based on blender and mechanical press extraction methods. 2. Materials and methods 2.1. Plant material Fifteen pomegranate (P. granatum, Punicaceae) cultivars grown in Georgia were used in this study. The cultivars Kaj-acik-anor, 0308-8146/$ - see front matter Ó 2012 Published by Elsevier Ltd. doi:10.1016/j.foodchem.2012.02.025 ⇑ Corresponding author. Tel.: +1 706 542 1067; fax: +1 706 542 1050. E-mail address: cakoh@uga.edu (C.C. Akoh). Food Chemistry 133 (2012) 1383–1393 Contents lists available at SciVerse ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem