title: Process optimization and characterization of fragrant oil from red pepper (Capsicum annuum L.) seed extracted by subcritical butane extraction.
abstract: BACKGROUND
  Red pepper seeds account for 450-500 g kg-1of the total pepper weight and are often discarded as waste. In this study, process optimization and characterization of fragrant oil from roasted red pepper seed extracted by subcritical butane extraction were carried out.
  
  
  RESULTS
  The optimal conditions of extraction were a temperature of 74.61 °C, a time of 68.65 min and a liquid/solid ratio of 30.24:1. The oil had a refractive index (25 °C) of 1.471, a relative density of 0.900, an acid value of 1.421 mg g-1oil, an iodine value of 127.035 g per 100 g, a saponification value of 184.060 mg KOH g-1, an unsaponifiable matter content of 12.400 g kg-1, a peroxide value of 2.465 meq. O2kg-1and a viscosity of 52.094 cP. The main fatty acids in the oil were linoleic acid (72.95%) followed by palmitic acid (11.43%) and oleic acid (10.00%). The oil showed desirable thermal and oxidative stability. A total of 19 volatile compounds, mostly aldehydes and alkenes, were identified from the oil.
  
  
  CONCLUSIONS
  The results indicated that the method is appropriate for the preparation of fragrant red pepper seed oil, and the oil is suitable for used as edible oil. © 2016 Society of Chemical Industry.
authors.affiliation: Henan Provincial Key Laboratory of Ion Beam Bio-engineering, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, China.
authors.forename: Ling-Biao
authors.initials: LB
authors.lastname: Gu
authors.affiliation: Henan Provincial Key Laboratory of Ion Beam Bio-engineering, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, China.
authors.forename: Hui-Li
authors.initials: HL
authors.lastname: Pang
authors.affiliation: Henan Provincial Key Laboratory of Ion Beam Bio-engineering, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, China.
authors.forename: Ke-Ke
authors.initials: KK
authors.lastname: Lu
authors.affiliation: Henan Provincial Key Laboratory of Ion Beam Bio-engineering, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, China.|College of Food Science and Technology, Henan University of Technology, Zhengzhou, China.
authors.forename: Hua-Min
authors.initials: HM
authors.lastname: Liu
authors.affiliation: College of Food Science and Technology, Henan University of Technology, Zhengzhou, China.
authors.forename: Xue-De
authors.initials: XD
authors.lastname: Wang
authors.affiliation: Henan Provincial Key Laboratory of Ion Beam Bio-engineering, and School of Physics and Engineering, Zhengzhou University, Zhengzhou, China.
authors.forename: Guang-Yong
authors.initials: GY
authors.lastname: Qin
mesh_terms: D002073:Butanes / Q000737:chemistry; D002212:Capsicum / Q000737:chemistry*; D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D010084:Oxidation-Reduction; D010938:Plant Oils / Q000737:chemistry* / Q000302:isolation & purification*; D012639:Seeds / Q000737:chemistry*
chemical_list: D002073:Butanes; D010938:Plant Oils; C046888:butane
keywords: fragrant red pepper seed oil; physicochemical properties; response surface methodology; subcritical butane extraction; volatile flavor compounds