Short‐ and long‐term retrogradation of potato starches with varying amylose content

Abstract

BACKGROUND: Gels of potato starches with varying amylose content were prepared and the degree of pasting and the course of retrogradation were studied. The average molar masses of granular and pasted starches were estimated. Determination of the degree of pasting involved use of optical microscopy and the study of pasting characteristics. The studies of susceptibility to retrogradation considered mechanical spectra, hardness, syneresis, resistant starch content, and X-ray measurements. RESULTS: Heating of the starch suspensions at 95 ∘ C resulted in almost complete deterioration of granules. Changes in storage modulus (G') exceeded these of loss modulus (G"). Values of G' and G", hardness and syneresis increased with the period of the sample storage and, simultaneously, the relevant tangent of the phase shift angle (tg (G"/G')) decreased. A tendency was observed for the resistant starch (RS) content to increase on prolonged storage of gels. The patterns of diffractograms for the pasted and lyophilized samples only differed slightly. CONCLUSION:The pastes of all the studied potato starches were characterized by a similar degree of pasting. The most essential changes in the physicochemical properties of the gels were observed between the 30th and 90th days of storage. The susceptibility of potato starch gels to retrogradation, especially within the first 2 h, was controlled, mainly by the amylose content.Resistant starch (RS) content. Samples containing 50 g kg −1 (m/m) starch were prepared following the method described in the section on texture, above. Directly after preparation, 45 cm 3 of the pastes were poured into 60 cm 3 polypropylene containers wileyonlinelibrary.com/jsfa J Sci Food Agric 2019; 99: 2393-2403 TextureThe hardness of all the samples investigated, after 1 and 2 h, was comparable (Fig. 3). An increase in hardness of the gels could be observed after the first day and then between the 30th and 90th days. This confirmed two-step, short-and long-term J Sci Food Agric 2019; 99: 2393-2403

Functionality of Native Starches in Food Systems: Cluster Analysis Grouping of Rheological Properties in Different Product Matrices

“…These have been extensively studied in terms of both native and modified starches, as well as their interaction with low molecular mass solutes and high molecular mass hydrocolloids. Most of all, common commercial starches such as corn, wheat, potato, cassava, or rice have been thoroughly examined [ 1 , 8 , 9 , 10 ]. Nevertheless, in recent years, there has been a growing interest in starches isolated from various plants, especially pulses [ 11 ], millet [ 12 ], and also less popular ones such as Phalaris canariensis L. or Solanum lycocarpum [ 13 ].…”

Molecular Analysis of Retrogradation of Corn Starches

“…Our former papers presented the results of studies on short- and long-term retrogradation of potato starches of various amylose content [27] and the effects of addition of non-starchy polysaccharide hydrocolloids on the process [28]. The results of 1 H NMR analyzes of retrogradation in pastes of these starches blended with non-starchy polysaccharide hydrocolloids were presented in our recent paper [29].…”

Analysis of the Retrogradation Processes in Potato Starches Blended with Non-Starchy Polysaccharide Hydrocolloids by LF NMR

“…This explain main role of amylose in network forming. These changes in T 1 , dependent on the starch variety, followed changes in DoC w for those starches [42].…”

“…Relationships between T 1 for particular pastes under study were close to the values of relative degree of crystallinity calculated involving diffractometry. The calculations for results collected for the pastes after 2 h storage gave DoC w declining from NPS1 to NPS2 [42].…”