Starch thermal processing

The approaches that were offered are illustrated in the patent literature of the time. Chiu et al.121 claim that starch heated after being adjusted to an alkaline pH value and then dried would behave as though it was crosslinked. In a patent awarded in 1999, Mahr and Trueck122 claim the use of amylose-containing starches complexed with lipid to enhance tolerance to thermal processing. Kettlitz and Coppin123 treated starch with activated chlorine to create a native product that was temperature-tolerant like a conventionally crosslinked starch. 

Biotec s product portfolio includes thermoplastic starch, which can be substituted for petrochemical based plastic packaging. Stanelco s radio frequency sealing technology can be used to process starch polymers without the degradation caused by other methods such as thermal processing. The purchase of Biotec will help the company develop alternatives to petroleum-based packaging. 

Chamberlain, E. K. 1996. Characterization of heated and thermally processed cross-linked waxy maize starch utilizing particle size analysis, microscopy and rheology. M. S. Thesis, Cornell University, Ithaca, NY. 

The antithixotropic nature of the thermally processed for 8, 15, and 30 min at 120°C cross-linked waxy maize (CWM) starch dispersions was observed clearly in shear cycles 5-min ascending and 5-min descending. The response curves of each sample (Figure 4-22) indicate that each sample became more viscous with shearing, that is, it exhibited time-dependent shear-thickening (antithixotropic) behavior. Further, the antithixotropic behavior was irreversible in that after the shearing was stopped the structure did not return to the structure prior to shearing. 

The common name dextrin was given in 1833 to the gum that resulted from treatment of starch with sulfuric add. This name is attributable to the direction of the optical rotation of the product. - The products of starch d radation by purely thermal processes arc called British gums, as they were acddentally discovered after a fire in Dublin, Ireland, destroyed a building having potato starch stored within it. The truth of this story is sometimes questioned, and it may be apocryphal, as there is no account of this fire in the Dublin newspapers of that period. ... 

Further chemical changes that occur during dextrinization should be discussed separately for the case of formation of British gum, and for variously catalyzed thermal processes. Thus, when starch (1) is heated in the presence of moisture, random hydrolytic scission at the (1 - 6), and more readily at the (1 — 4), linkages has been proposed to occur in the branched chains of amylopectin, to give more-linear structures, leading to the observed decrease in viscosity. o-Glucosyl oxocarbonium ions (2) were postulated as intermediates, but free radicals (3) formed by homolytic fission at the (1 4)-glycosidic bond are also feasible. 

Wu, M. C., Hamann, D. C., Lanier, T. C. (1985a). Rheological and calorimetric investigations of starch-fish protein systems during thermal processing. J. Texture Stud. 16,53-74. 

Becker A., Hill S.E., and Mitchell J.R. 2001. Relevance of amylose-lipid complexes to the behavionr of thermally processed starches, Starch/Stderke, 53, 3-4, 121. 

Thermal processing of starch-based polymers involves multiple chemical and physical reactions, e.g. water diffusion, granule expansion, gelatinization, decomposition, melting and crystallization [8]. Among the various phase... 

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