Potential of flaxseed in the development of omega-3 rice paper with antioxidant activity Shana J. Cameron a, b , Farah Hosseinian a, b, * a Food Science and Nutrition Program, Chemistry Department, Carleton University, Ottawa, Ontario, Canada K1S 5B6 b Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada K1S 5B6 article info Article history: Received 25 July 2012 Received in revised form 20 November 2012 Accepted 9 December 2012 Keywords: Rice paper Antioxidant Flaxseed Omega-3 Nutritional value Sensory evaluation ORAC DPPH Total phenolics abstract The objective of this study was to enhance the nutritional quality and antioxidant activity of rice paper by adding ground whole flaxseed to develop omega-3 rice paper (ORP). The amounts of omega-3 and dietary fibre in the ORP were 2.7 g/100 g and 9.1 g/100 g respectively, both of which were absent in the traditional rice paper (TRP). The antioxidant activity of the ORP evaluated by the oxygen radical absor- bance capacity (ORAC) (231.7 mmol TE/g) was significantly higher than that of TRP (50.2 mmol TE/g). This correlated well with the results of the DPPH radical scavenging activity. In addition, the total phenolic content of the ORP was much higher than the total phenolic content of the TRP. Sensory analysis indi- cated that ORP was preferred in all of the tested attributes, particularly in taste and texture. The results suggest that the development of ORP by the addition of flaxseed improved both the nutritional value and the sensory characteristics of rice paper. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction The nutritional properties and health benefits of flaxseed (Linum usitatissimum) have gained world-wide attention in research as well as being utilized in the food industry. Studies have indicated that flaxseed provides potential health benefits, such as decreasing the risk of cardiovascular disease (CVD) (Bloedon & Szapary, 2004), diabetes (Haliga et al., 2009), and cancer (Jhala, 2010). Flaxseed is composed of 40e50 g/100 g oil, 23e34 g/100 g protein, 5 g/100 g mucilage, 4 g/100 g ash, and 9e30 mg/g lignan precursors, varying with the cultivar and growth environment (Touré & Xueming, 2010). The health benefits from flaxseed can be credited mainly to its abundance in omega-3 fatty acids, dietary fibre, high quality proteins, and antioxidants such as lignan and other phenolics (Hussain, Anjum, & Alamri, 2011). Flax has high oil content (41 g/100 g) in its seeds (Bloedon & Szapary, 2004). Flaxseed oil is low in saturated fat (9 g/100 g) and rich in polyunsaturated fat (73 g/100 g) (Bloedon & Szapary, 2004). Approximately 51e55 g/100 g of the total fatty acids in flaxseed oil are Alpha-Linolenic acid (ALA, 18:3, u-3) (Vijaimohan et al., 2006). The high quantity of this essential omega-3 fatty acid makes flax- seed oil the leading plant source for omega-3 fatty acids. The omega-3 fatty acids play a vital role in improving immunological function (Oomah, 2001), decreasing inflammation (Simopoulos, 2002), and decreasing the risk of CVD (Oomah, 2001). The abundance of phenolic compounds such as lignan, secoi- solariciresinol diglucoside (SDG), and ferulic acid in flaxseed contributes to its well-known antioxidant properties (Kasote, Hegde, & Deshmukh, 2011). The addition of these natural antioxi- dants from flaxseed may play an important role in the prevention of lipid oxidation of foods to enhance their shelf life (Kasote et al., 2011). Flaxseed is also rich in soluble and insoluble dietary fibre. Soluble fibre (mucilage) aids in decreasing cholesterol and opti- mizing blood glucose levels (Hussain et al., 2011). In addition, flaxseed contains all of the essential amino acids that are crucial for the synthesis of proteins that regulate and maintain proper cellular function (Oomah & Mazza, 1993). Fortification of food with flaxseed is gaining popularity in the development of functional foods. Previous studies have investigated * Corresponding author. Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6. Tel.: þ1 613 520 2600x2048; fax: þ1 613 520 3749. E-mail address: farah_hosseinian@carleton.ca (F. Hosseinian). Contents lists available at SciVerse ScienceDirect LWT - Food Science and Technology journal homepage: www.elsevier.com/locate/lwt 0023-6438/$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.lwt.2012.12.004 LWT- Food Science and Technology 53 (2013) 170e175