Effect of Thermal Processing of Dietary Fibers on the Bioavailability of Proteins from Wheat and Barley Flour

Rodica Căpriță, Adrian Caprita, Iuliana Cretescu


Changes in particle size, solubility and chemical structure of different fiber components can cause changes in the bioavailability of some nutrients. Numerous studies have shown a reduction in apparent digestion of proteins in the gastrointestinal tract caused by direct and indirect processes. Endogenous nitrogen losses are due to increased secretion of digestive juices and increased desquamation in the presence of dietary fiber. Food fibers reduce digestion of food and endogenous proteins. Food processing can improve the bioavailability of proteins. Reduction of thermally latent antinutritional factors, such as trypsin inhibitors, phytates and polyphenols, as well as partial denaturation of proteins by heat treatment contributes to their digestibility. Protein quality in processed foods decreases primarily due to reduced lysine bioavailability. Experiments revealed an increase in protein digestibility (PD) in whole wheat flour heated samples in a forced air oven at 150°C over 0-10 minutes: 31.8% at time 0, 43.73% at 5 minutes and 48.43% at 10 minutes of heating. When heating for 15 minutes, digestibility decreased to near the unprocessed sample value (33.8%). PD in wheat samples exposed to microwave for 30, 60 and 90 seconds increased throughout the entire time period, with a maximum of 45.06% when exposed for 90 seconds. PD increased moderately in whole barley flour samples heated at 150°C, from 27.46% for the unprocessed sample to a maximum of 33.47% for the 5 minutes heated sample. PD in barley samples exposed to microwave was higher than in the unprocessed sample, with a maximum of 36.34% for 30 seconds exposure.


wheat, barley, thermal processing, protein digestibility

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Khan, M. A, Mahr-Un-Nisa, and M. Sarwar, M., Techniques Measuring Digestibility for the Nutritional Evaluation of Feeds, International Journal of Agriculture & Biology, 2003, 5(1), 91–94.

Martens, D. R. 2005. Rate and extent of digestion. In: Dijkstra, J., Forbes, J. M., and France, J. (eds.) Quantitative aspects of ruminant digestion. CABI International, Wallingford, UK. 2nd edition, pp. 13–47.

Boisen, S., Eggum, B. O., Critical evaluation of in vitro methods for estimating digestibility in simple-stomach animals, Nutrition Research Reviews, 1991, 4, 141-162.

Löwgren, W., Graham, H., and Aman, P., An in vitro method for studying digestion in the pig. Simulating digestion in the different compartments of the intestine, British Journal of Nutrition, 1989, 61, 673–687.

Boisen, S., Fernández, J.A., Prediction of the total tract digestibility of energy in feedstuffs and pig diets by in vitro analyses, Animal Feed Science and Technology, 1997, 68, 277–286.

Dierick, N., Vervaeke, I., Decuypere, J., and Hendrickx, H., Protein digestion in pigs measured in vivo and in vitro. In: Digestive Physiology in the Pig, A. Just, H. Jerrgensen and J. A. Fernandez eds., National Institute of Animal Science, Copenhagen, 1985, pp. 329-332.

Sauer, W. C., Jorgensen, H., Berzins, R., A modified nylon bag technique for determining apparent digestibilities of protein in feedstuffs for pigs, Canadian Journal of Animal Science, 1983, 63, 233-237.

Sauer, W. C., den Hartog, L. A., Huisman, J., van Leeuwen, P., and de Lange, C. F. M., The evaluation of the mobile nylon bag technique for determining the apparent protein digestibility in a wide variety of feedstuffs for pigs, Journal of Animal Science, 1989, 67, 432-440.

Pujol, S., Torrallardona, D., Evaluation of in vitro methods to estimate the in vivo nutrient digestibility of barley in pigs, Livestock Science, 2007, 109, 186–188.

Noblet, J., Jaguelin-Peyraud, Y., Prediction of digestibility of organic matter and energy in the growing pig from an in vitro model, Animal Feed Science and Technology, 2007, 134, 211–222.

Wilfart, A., Jaguelin-Peyraud, Y., Simmins, H., Noblet, J., van Milgen, J., and Montagne, L., Kinetics of enzymatic digestion of feeds as estimated by a stepwise in vitro method, Animal Feed Science and Technology, 2008, 141, 171–183.

. Lin, Y.; Chen, K.; Tu, D.; Yu, X.; Dai, Z.; Shen, Q. Characterization of dietary fiber from wheat bran (Triticum aestivum L.) and its e_ect on the digestion of surimi protein. LWT 2019, 102, 106–112. [CrossRef]

Caprita, A., Caprita, R., The effect of thermal processing on soluble dietary fibre fraction in wheat, Journal of Food, Agriculture & Environment, 2011, 9, 14-15

Căpriţă, R., Căpriţă A., The variation of relative and reduced viscosity with concentration in wheat and barley aqueous extracts, Scientific Papers: Animal Science and Biotechnologies, 2012, 54(2), 117-120.

Caprita, R., Caprita, A., Julean, C., Pandur, C., Drinceanu, D., Stef L., Relationship between feed water extract viscosity and intestinal viscosity in poultry, J. Biochem., 2010, 150, 199.

Pernollet, J.C. Protein bodies of seeds: Ultrastructure, biochemistry, biosynthesis and degradation. Phytochemistry 1978, 17, 1473–1480. [CrossRef]

Duodu, K.G.; Taylor, J.R.N.; Belton, P.S.; Hamaker, B.R. Factors affecting sorghum protein digestibility. J. Cereal Sci. 2003, 38, 117–131. [CrossRef]

Bhattarai, R.R.; Dhital, S.; Wu, P.; Chen, X.D.; Gidley, M.J. Digestion of isolated legume cells in a stomach-duodenum model: Three mechanisms limit starch and protein hydrolysis. Food Funct. 2017, 8, 2573–2582. [CrossRef] [PubMed]

Gulati, P.; Li, A.; Holding, D.; Santra, D.; Zhang, Y.; Rose, D.J. Heating Reduces Proso Millet Protein Digestibility via Formation of Hydrophobic Aggregates. J. Agric. Food Chem. 2017, 65, 1952–1959. [CrossRef]

.Nikmaram, N.; Leong, S.Y.; Koubaa, M.; Zhu, Z.; Barba, F.J.; Greiner, R.; Oey, I.; Roohinejad, S. Effect of extrusion on the anti-nutritional factors of food products: An overview. Food Control 2017, 79, 62–73. [CrossRef]

Caprita, R., Caprita, A., Chemical methods for the determination of soluble and insoluble non-starch polysaccharides, Scientific Papers: Animal Science and Biotechnologies, 2011, 44 (2), 73-80

Joye, I. Protein Digestibility of Cereal Products, Foods 2019, 8, 199.

Li, W. F., Sun, J. Y., Xu, Z. R., Effects of NSP degrading enzyme on in vitro digestion of barley, Asian-Aust. J. Anim. Sci., 2004, 17, 122-126.

AOAC, Association of Official Analytical Chemists. Official Methods of Analysis, K Helrick, ed. 13th edition. Arlington, 1990, pp. 101


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