Protein enriched pasta: structure and digestibility of its protein network

Food Funct. 2016 Feb;7(2):1196-207. doi: 10.1039/c5fo01231g.

Abstract

Wheat (W) pasta was enriched in 6% gluten (G), 35% faba (F) or 5% egg (E) to increase its protein content (13% to 17%). The impact of the enrichment on the multiscale structure of the pasta and on in vitro protein digestibility was studied. Increasing the protein content (W- vs. G-pasta) strengthened pasta structure at molecular and macroscopic scales but reduced its protein digestibility by 3% by forming a higher covalently linked protein network. Greater changes in the macroscopic and molecular structure of the pasta were obtained by varying the nature of protein used for enrichment. Proteins in G- and E-pasta were highly covalently linked (28-32%) resulting in a strong pasta structure. Conversely, F-protein (98% SDS-soluble) altered the pasta structure by diluting gluten and formed a weak protein network (18% covalent link). As a result, protein digestibility in F-pasta was significantly higher (46%) than in E- (44%) and G-pasta (39%). The effect of low (55 °C, LT) vs. very high temperature (90 °C, VHT) drying on the protein network structure and digestibility was shown to cause greater molecular changes than pasta formulation. Whatever the pasta, a general strengthening of its structure, a 33% to 47% increase in covalently linked proteins and a higher β-sheet structure were observed. However, these structural differences were evened out after the pasta was cooked, resulting in identical protein digestibility in LT and VHT pasta. Even after VHT drying, F-pasta had the best amino acid profile with the highest protein digestibility, proof of its nutritional interest.

MeSH terms

  • Amino Acids / analysis
  • Cooking
  • Dietary Proteins / analysis*
  • Digestion
  • Egg Proteins / chemistry
  • Flour / analysis
  • Food Handling*
  • Food Quality
  • Food, Fortified / analysis*
  • Glutens / chemistry
  • Hot Temperature
  • Spectroscopy, Fourier Transform Infrared
  • Triticum / chemistry
  • Vicia faba / chemistry

Substances

  • Amino Acids
  • Dietary Proteins
  • Egg Proteins
  • Glutens