title: Combined effects of independent variables on yield and protein content of pectin extracted from sugar beet pulp by citric acid.
abstract: The extraction of pectin from sugar beet pulp by citric acid was carried out under different conditions using Box-Behnken design for four independent variables (pH, temperature, time and liquid to solid ratio). The yield of sugar beet pulp pectin ranged from 6.3% to 23.0%, and the content of protein from 1.5% to 4.5%. All independent variables significantly affected the yield, and all variables except liquid to solid ratio significantly affected the protein content. The yield increased as decreasing pH of extracting solution, extending time and advancing temperature, and an opposite relationship of effects between variables and content of protein was obtained. The chemical composition of collected samples was determined. Moreover, from the results of emulsifying properties study, the extracted pectin from sugar beet pulp could prepare steady oil-in-water emulsions. Therefore, it was inferred that the extraction conditions could influence yield and protein content, resulting in different emulsifying property.
authors.affiliation: College of Chemical Engineering, Xinjiang Agricultural University, Urumchi, Xinjiang 830052, China. Electronic address: 18799182336@163.com.
authors.forename: De-Qiang
authors.initials: DQ
authors.lastname: Li
authors.affiliation: College of Chemical Engineering, Xinjiang Agricultural University, Urumchi, Xinjiang 830052, China.
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Du
authors.affiliation: College of Chemical Engineering, Xinjiang Agricultural University, Urumchi, Xinjiang 830052, China.
authors.forename: Wei-Wen
authors.initials: WW
authors.lastname: Jing
authors.affiliation: College of Chemical Engineering, Xinjiang Agricultural University, Urumchi, Xinjiang 830052, China.
authors.forename: Jun-Fang
authors.initials: JF
authors.lastname: Li
authors.affiliation: College of Chemical Engineering, Xinjiang Agricultural University, Urumchi, Xinjiang 830052, China.
authors.forename: Jia-Yu
authors.initials: JY
authors.lastname: Yan
authors.affiliation: College of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Liu
mesh_terms: D000704:Analysis of Variance; D027461:Beta vulgaris / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008962:Models, Theoretical; D010368:Pectins / Q000302:isolation & purification*; D010940:Plant Proteins / Q000032:analysis*; D012996:Solutions; D013696:Temperature; D013997:Time Factors
chemical_list: D004655:Emulsions; D010940:Plant Proteins; D012996:Solutions; D019343:Citric Acid; D010368:Pectins
keywords: Citric acid; Emulsifying properties; Pectin; Protein content; Sugar beet pulp