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Starch structure and digestibility Enzyme-Substrate relationship
Published online by Cambridge University Press: 18 September 2007
Abstract
Digestion of starch is effected by hydrolysing enzymes in a complex process which depends on many factors; these include the botanical origin of starch, whether the starch is amorphous or crystalline, the source of enzymes, substrate and enzyme concentration, temperature and time, as well as the presence of other substances in the multicomponent matrix in which starch occurs naturally, e.g. cereal grains. Native starch is digested (i.e. hydrolysed) slowly compared with processed (gelatinised) starch whose crystallinity has been lost and where the accessibility of substrate to enzymes is greater and not restricted by α-glucan associations such as double helices (especially in crystallites) or amylose-lipid complexes (in cereal starches). The restriction of starch digestion (primarily in the human digestive system) due to forms which are resistant to hydrolysis has led to the concept of dietary ‘resistant-starch’. Different forms of resistance can be identified which hinder hydrolysis. With regard to digestibility, whether in the human or animal digestive tract, it is important to understand the mechanisms of enzymatic hydrolysis, and the consequence of incomplete digestion i.e. the potential loss of glucose as a valuable source of energy. This review deals with starch hydrolysis by specific amylases in model (in vitro) and more broadly in in vivo systems. The optimisation of starch hydrolysis and digestion is discussed in the light of modern knowledge.
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References
Bettge, A.D., Giroux, M.J. and Morris, C.F. (2000) Susceptibility of waxy starch granules to mechanical damage. Cereal Chemistry 77: 750–753.Google Scholar
Classen, H.L. (1996) Cereal grain starch and exogenous enzymes in poultry diets. Animal Feed Science and Technology 62: 21–27.CrossRefGoogle Scholar
Donald, A.M., Waigh, T.A., Jenkins, P.J., Gidley, M.J., Debet, M. and Smith, A. (1997) Internal structure of starch granules revealed by scattering studies, in: Starch Structure and Functionality (Frazier, P. J., Donald, A. M. and Richmond, P. eds), pp 172–179, Cambridge: The Royal Society of Chemistry.Google Scholar
Edwards, C. and Tester, R.F. (1998) Carbohydrates (d) resistant starch and oligo saccharides, in: Encyclopaedia of Human Nutrition (Caballero, B. and Strain, J. J. eds), pp 289–295, London: Academic Press.Google Scholar
Englyst, H.N. and Hudson, G.J. (1997) Starch and health, in: Starch Structure and Functionality (Frazier, P. J., Donald, A. M. and Richmond, P. eds), pp 9–21, Cambridge: Royal Society of Chemistry.Google Scholar
Englyst, H.N., Kingman, S.M. and Cummings, J.H. (1992) Classification and measurement of nutritionally important starch fractions. European Journal of Clinical Nutrition 46: S33–S50.Google Scholar
Karkalas, J., Tester, R.F. and Morrison, W.R. (1992) Properties of damaged starch granules. I. Comparison of a micromethod for the enzymic determination of damaged starch with the standard AACC and Farrand methods. Journal of Cereal Science 16: 237–251.CrossRefGoogle Scholar
Lauro, M., Forssell, P.M., Suortti, M.T., Hulleman, S.H.D. and Poutenen, K.S. (1999) Alpha-amylolysis of large barley starch granules. Cereal Chemistry 76: 925–930.CrossRefGoogle Scholar
Lauro, M., Poutanen, K. and Forssell, P. (2000) Effect of partial gelatinisation and lipid addition on alpha-amylase of barley starch granules. Cereal Chemistry 77: 595–601.CrossRefGoogle Scholar
Manelius, R., Qin, Z., Avall, A.K., Andtfolk, H. and Bertoft, E. (1997) The mode of action on granular wheat starch by bacterial alpha-amylase. Starch/Stärke 49: 142–147.Google Scholar
Morrison, W.R. (1993) Cereal starch granule development and composition, in: Seed Storage Compounds: Biosynthesis, Interactions and Manipulation (Shewry, P.R. and Stobart, K. eds), pp 175–190. Oxford: Oxford Science Publications.Google Scholar
Morrison, W.R. and Karkalas, J. (1990) Starch, in: Methods in Plant Biochemistry (Dey, P. M. ed.), Volume 2, pp 323–352. London: Academic Press.CrossRefGoogle Scholar
Nicol, N.T., Wiseman, J. and Norton, G. (1993) Factors determining the nutritional value of wheat varieties for poultry. Carbohydrate Polymers 21: 211–215.Google Scholar
Sayikaya, E., Higasa, T., Adachi, M. and Mikami, B. (2000) Comparison of degradation abilities of α- and β-amylases on raw starch granules. Process Biochemistry 35: 711–715.CrossRefGoogle Scholar
Tester, R.F. (1997) properties of damaged starch granules: composition and swelling properties of maize, rice, pea and potato starch fractions in water at various temperatures. Food Hydrocolloids 11: 293–301.Google Scholar
Tester, R.F., Debon, S.J.J. and Sommerville, M.D. (2000) Annealing of maize starch. Carbohydrate Polymers 42: 287–299.CrossRefGoogle Scholar
Tester, R.F. and Karkalas, J. (2002) Starch, in: Biopolymers, Polysaccharides II: Polysaccharides from Eukaryotes, (Steinbüchel, A. series ed.; Vandamme, E. J., De Baets, S. and Steinbüchel, A. eds), Volume 6, pp 381–438. Weinheim: Wiley-VCH.Google Scholar
Tester, R.F., Morrison, W.R., Gidley, M.J., Kirkland, M. and Karkalas, J. (1994) Properties of damaged starch granules. III. Microscopy and particle size analysis of undamaged granules and remnants. Journal of Cereal Science 20: 59–67.CrossRefGoogle Scholar
Tester, R.F. and Sommerville, M.D. (2000) Swelling and enzymatic hydrolysis of starch in low water systems. Journal of Cereal Science 33: 193–203.CrossRefGoogle Scholar
Tester, R.F. and Sommerville, M.D. (2003) the effects of non-starch polysaccharides on the extent of gelatinisation, swelling and α-amylase hydrolysis of maize and wheat starches. Food Hydrocolloids 17: 41–54.CrossRefGoogle Scholar
Weurding, R.E., Enting, H. and Verstegen, M.W.A. (2003) The relation between starch digestion rate and amino acid level for broiler chickens. Poultry Science 82: 279–284.CrossRefGoogle ScholarPubMed