Characterization of chemical, molecular, thermal and rheological properties of medlar pectin extracted at optimum conditions as determined by Box-Behnken and ANFIS models

Al-Amoudi R. H., Taylan O., Kutlu G., Can A., SAĞDIÇ O., Dertli E., ...More

Food Chemistry, vol.271, pp.650-662, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 271
  • Publication Date: 2019
  • Doi Number: 10.1016/j.foodchem.2018.07.211
  • Journal Name: Food Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.650-662
  • Keywords: Medlar fruit, Pectin extraction yield, RSM and ANFIS modeling, Molecular, thermal and rheological characterization
  • Istanbul Gelisim University Affiliated: Yes


In this work, response surface methodology and adaptive neuro-fuzzy inference system approaches were used to predict and model effect of extraction conditions of pectin from medlar fruit (Mespilus germanica L.). The pectin extracted at optimized conditions (89 °C, 4.83 h and 4.2 pH) could be classified as high methoxyl pectin. Sugar composition analysis showed that pectin was mainly composed of D-galacturonic acid, L-arabinose, L-rhamnose, D-galactose and D-glucose. Fourier Transform Infrared Spectroscopy, RAMAN and nuclear magnetic resonance spectra confirmed molecular structure, revealing presence of D-galacturonic acid backbone. X-ray diffraction patterns revealed an amorphous structure. Differential scanning calorimetry showed endothermic (123 °C) and exothermic peaks (192 °C). Thermogravimetric analysis revealed three decomposition regions, 50–225 °C, 225–400 °C and 400–600 °C. Steady and dynamic shear analyses revealed that pectin had a pseudo-plastic behavior with storage (G′) and loss (G″) modulus increasing with increment in frequency, indicating viscoelastic structure more predominantly elastic than viscous.