Comparative Analysis Reveals Changes in Some Seed Properties in Amaranth Mutant Variety ‘Zobor’ (A. hypochondriacus × A. hybridus)

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.

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Physicochemical, Microstructural, and Rheological Characterization of Tigernut (Cyperus esculentus) Starch

International Journal of Food Science ◽

10.1155/2019/3830651 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

P. T. Akonor ◽

C. Tortoe ◽

C. Oduro-Yeboah ◽

E. A. Saka ◽

J. Ewool

Keyword(s):

Physicochemical Properties ◽

Amylose Content ◽

Flow Behavior ◽

Pasting Properties ◽

Cyperus Esculentus ◽

Rheological Characterization ◽

Freeze Thaw ◽

Starch Gels

The aim of this study was to characterize the physicochemical properties of starch isolated from two varieties of tigernuts. The results showed wide variations between the two types of tigernuts. Mean granule sizes were 11.1 and 6.1 μm, respectively, for starch from the yellow and black while amylose content ranged from 19 to 21%. Starch gels from the yellow variety were more stable to freeze-thaw and recorded 37.1% syneresis, compared to 56.5% after the first storage cycle. Pasting properties were significantly different (p < 0.05) among starch from the two tigernut varieties, with black recording higher peak viscosity, lower breakdown, and higher setback viscosity. Gels made from the yellow variety were clearer, softer, more adhesive, and more cohesive. Both gels showed a pseudoplastic flow behavior without thixotropy.

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Applications of ultramicrotomy for materials characterization

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147004 ◽

1993 ◽

Vol 51 ◽

pp. 232-233

Author(s):

R.T. Blackham ◽

J.J. Haugh ◽

C.W. Hughes ◽

M.G. Burke

Keyword(s):

Materials Science ◽

Microstructural Analysis ◽

Analytical Electron Microscopy ◽

Austenitic Stainless Steels ◽

Specimen Preparation ◽

Preparation Technique ◽

Thermally Induced ◽

Radiation Induced ◽

Characterization Of Materials

Essential to the characterization of materials using analytical electron microscopy (AEM) techniques is the specimen itself. Without suitable samples, detailed microstructural analysis is not possible. Ultramicrotomy, or diamond knife sectioning, is a well-known mechanical specimen preparation technique which has been gaining attention in the materials science area. Malis and co-workers and Glanvill have demonstrated the usefulness and applicability of this technique to the study of a wide variety of materials including Al alloys, composites, and semiconductors. Ultramicrotomed specimens have uniform thickness with relatively large electron-transparent areas which are suitable for AEM anaysis.Interface Analysis in Type 316 Austenitic Stainless Steel: STEM-EDS microanalysis of grain boundaries in austenitic stainless steels provides important information concerning the development of Cr-depleted zones which accompany M23C6 precipitation, and documentation of radiation induced segregation (RIS). Conventional methods of TEM sample preparation are suitable for the evaluation of thermally induced segregation, but neutron irradiated samples present a variety of problems in both the preparation and in the AEM analysis, in addition to the handling hazard.

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