Preparation and physicochemical properties of soluble dietary fiber from orange peel assisted by steam explosion and dilute acid soaking

Food Chem. 2015 Oct 15:185:90-8. doi: 10.1016/j.foodchem.2015.03.112. Epub 2015 Apr 3.


The coupled pretreatment of orange peel with steam explosion (SE) and sulfuric-acid soaking (SAS) was investigated to enhance the yield and improve the functionality of soluble dietary fiber (SDF). When orange peel was pretreated by SE at 0.8MPa for 7 min, combined with 0.8% SAS, the content of SDF was increased from 8.04% to 33.74% in comparison to the control and SDF prepared with SE-SAS showed the high water solubility, water-holding capacity, oil-holding capacity, swelling capacity, emulsifying activity, emulsion stability and foam stability. SDF from orange peel treated by SE-SAS exhibited significantly (p < 0.05) higher binding capacity for three toxic cations (Pb, As and Cu) and smaller molecular weight (Mw = 174 kDa). Furthermore, differential scanning calorimetry (DSC) measurement showed that SDF from orange peel treated by SE-SAS had a higher peak temperature (170.7 ± 0.4 °C) than that of the untreated sample (163.4 ± 0.3 °C). Scanning electron micrograph (SEM) images demonstrated that the surface of SDF from orange peel treated by SE-SAS was rough and collapsed. It can be concluded that SDF from orange peel treated by SE-SAS has the higher potential to be applied as a functional ingredient in food products.

Keywords: Orange peel; Physicochemical properties; Soluble dietary fiber; Steam explosion; Sulfuric-acid soaking.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calorimetry, Differential Scanning
  • Chemical Phenomena
  • Citrus sinensis / chemistry*
  • Dietary Fiber / analysis*
  • Food Handling / methods*
  • Fruit / chemistry
  • Microscopy, Electron, Scanning
  • Molecular Weight
  • Solubility
  • Steam*
  • Sulfuric Acids / chemistry
  • Water


  • Dietary Fiber
  • Steam
  • Sulfuric Acids
  • Water
  • sulfuric acid