Unieke eigenschappen van SHS-G : TNO ontwikkelt nieuwe vetvervanger op zetmeelbasis

TNO Kwaliteit van Leven heeft een nieuwe vetvervanger op zetmeelbasis ontwikkeld, die als 'clean label'-ingrediënt toegepast kan worden. Het is in lage concentraties al functioneel. Hierdoor is er minder van nodig, wat leidt tot een lagere energie-inname bij consumptie

Origins of the poor filtration characteristics of wheat starch hydrolysates

The effects of wheat starch components on the filtration characteristics of wheat starch hydrolysates were investigated with a model-based approach. The filtration rate was not affected by the removal of the pentosans or by altering the conformation of the protein. On the other hand, the filtration rate increased when a hydrolysate was defatted with chloroform or butanol. Some commercially available enzymes also increased the filtration rate. The filtration rate of potato starch hydrolysates decreased when gluten, pentosans, solubles, or propanol extract from defatted wheat starch were added. The latter had by far the largest effect. The composition of this extract was 65% lipid and 11% protein. The main lipid in wheat starch is lysophosphatidylcholine (LPC). This single-chain lipid forms micelles above a concentration of 0.025 g/kg. The filtration rate decreased when LPC was added to potato starch hydrolysates or glucose solutions at concentrations above the critical micelle concentration. This effect of LPC on glucose solutions proves that the filtration characteristics are not related to the formation of amylose-lipid complexes. Therefore, micelle formation must be responsible for the effect of LPC on the filtration rate. The critical micelle concentration is only 2.5% of the amount of lysophospholipids in wheat starch hydrolysates. Thus, almost all of these lipids have to be removed from wheat starch hydrolysates to increase the filtration rate

Surface effects in the acetylation of granular potato starch

The occurrence of surface effects in the acetylation of granular potato starch with acetic anhydride to degrees of substitution 0.04-0.2 was studied by two different approaches. The first approach involved the fractionation of granular starch acetates into five different size classes and analysis of their acetate content. Alternatively, two narrow size fractions of potato starch acetate granules were surface-peeled by chemical gelatinization in 5 M CaCl2, and the remaining cores were analyzed for acetyl content at different peeling levels. It was established that true surface peeling occurs in this medium and that the ester linkages are stable under the conditions applied. Both approaches led to the conclusion that the acetylation of potato starch granules is accompanied by a pronounced surface effect. The surface peeling method allows determination of the extent of substitution as a function of the radial position in the starch granule. © 2008 Elsevier Ltd. All rights reserved

Laboratory-scale dry/wet-milling process for the extraction of starch and gluten from wheat

A laboratory-scale process is presented for the manufacture of starch and gluten from wheat. Main feature of this process is that whole wheat kernels are crushed dry between smooth rolls prior to wet disintegration in excess water in such way that gluten formation is prevented and fibres can be removed by sieving. Centrifugation of the endosperm suspension yields a dough which can be separated into starch and gluten using an established batter process. The results suggest that starch recovery is increased in comparison to a conventional wheat flour process without a concomitant decrease in protein recovery. Although starch purification was omitted, a total starch with a low protein content is obtained. On the other hand, the protein content of the gluten fraction is rather low due to difficulties in removing thestarch. Despite this, the effect on dough mechanical properties by the addition of gluten obtained from wet-milled wheat is comparable to the effect of gluten from flour. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Identification of the thermal transitions in potato starch at a low water content as studied by preparative DSC

The aim of this work was to identify the transitions in the complex DSC profiles of potato starch at a low water content. Preparative DSC involves the thermal processing of samples in stainless steel DSC pans in a way that allows their subsequent structural characterization. The low temperature (LT), dual melting (M1-M2), and high temperature (HT) endotherms observed in DSC profiles of potato starch with 16% water were assigned to enthalpy relaxation, melting with preservation of granular identity, and transition of the melted granules into a molecular melt, respectively. Granular melting was accompanied by a strong reduction of swelling capacity. Significant molecular degradation was observed after the HT transition. There is evidence that HT does not represent a true thermodynamic transition, but is due to a volume change in the sample. In contrast to potato starch, maize starch with 16% water gave inhomogeneous samples after processing, presumably because of its low packing density. © 2009 Elsevier Ltd. All rights reserved

Substitution patterns in methylated potato starch as revealed from the structure and composition of fragments in enzymatic digests

The effect of the granule structure on the methylation of starch was investigated by comparing the substitution patterns of potato starch methylated in granular suspension and in solution to DS 0.3. Substitution patterns were analyzed by successive digestion with α-amylase and amyloglucosidase, fractionation of the resulting malto-oligosaccharide mixture by GPC on a preparative scale, and characterization of the fractions by GLC and MALDI-MS. The mass composition of fractions with intermediate and higher degree of polymerization was indicative of enhanced clustering of substituents in granular methyl starch. On the contrary, the composition of the smaller saccharides was governed by enzyme specificity, which was also reflected in strong deviations in their monomer composition. A sequencing study on selected 'pure' small saccharides confirmed and complemented previous conclusions on enzyme specificity. © 2008 Elsevier Ltd. All rights reserved