Rheological behaviors, structural properties and freeze-thaw stability of normal and waxy genotypes of barley starch: a comparative study with mung bean, potato, and corn starches

Authors: ZHAO, SHENCHI - Northeast Agricultural University; FENG, YANGYANG - Northeast Agricultural University; KONG, BAOHUA - Northeast Agricultural University; XIA, XIUFANG - Northeast Agricultural University; Hu, Gongshe; LIANG, XI - University Of Idaho; LIU, QIAN - (NCE, CECR)networks Of Centres Of Exellence Of Canada, Centres Of Excellence For Commercilization A

Submitted to: Food Science and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/8/2021
Publication Date: 8/26/2021
Citation: Zhao, S., Feng, Y., Kong, B., Xia, X., Hu, G., Liang, X., Liu, Q. 2021. Rheological behaviors, structural properties and freeze-thaw stability of normal and waxy genotypes of barley starch: a comparative study with mung bean, potato, and corn starches. Food Science and Biotechnology. 30: 1171-1181. https://doi.org/10.1007/s10068-021-00967-z.
DOI: https://doi.org/10.1007/s10068-021-00967-z

Interpretive Summary: The high content of beta-glucan in food barley may provide unique properties of starch in food industry uses. Characterization of high beta-glucan barley starch sample with other source starch is the basic requirement to promote wider industrial uses. Starch samples from the high beta-glucan variety Transit have been compared to the feed barley variety of Tetonia, as well as starch samples of Mung bean, corn, and potato in rheological behaviors, structural properties, and freeze-thaw stabilities. Results showed that starch samples from Transit have the highest gelatinization temperature and the best freeze-thaw stability. Those unique properties of high beta-glucan food barley starch may help to expand its industrial uses in the future, and then potentially benefit barley growers and economy.

Technical Abstract: The rheological behaviors, structural properties and freeze-thaw stability of starch isolated from two barley varieties, namely Tetonia and Transit, were investigated, along with other common starch sources (mung bean, potato, and corn) for comparison. Transit barley starch is a waxy starch, which showed the lowest storage modulus (G') and the loss modulus (G") values, as well as the highest loss tangents (tan d) during a frequency sweep test, which suggested a predominance of elastic properties over viscous properties. However, the tan d of Tetonia barley starch (a typical normal starch) was similar to that of potato starch, which indicated more solidity in comparison to Transit barley starch. Transit barley starch had the highest gelatinization temperature and the lowest gelatinization enthalpy (P < 0.05). Moreover, Tetonia and Transit barley starches displayed weak diffraction peak intensities by X-ray diffraction analysis, with intensities similar to corn starch. Additionally, Transit barley starch showed the lowest % syneresis even when freeze-thawed up to five cycles (P < 0.05). However, Tetonia barley starch had the worst freeze-thaw stability (P < 0.05), which was verified via scanning electron microscopy analysis of freeze-thawed starch gels.