Linked Life Data

16819933

Source:http://linkedlifedata.com/resource/pubmed/id/16819933

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
2006-7-5
pubmed:abstractText
Retrogradation in rice is a trait that describes the hardening of cooked rice after storage or cooling, and it has significant implications for many consumers of rice, since many people cook rice in the morning and consume it several hours later or the next day. Tools to select against retrogradation in breeding programs are yet to be described. Here, we aim to determine the effect on retrogradation of storage time and temperature and the role of starch, protein, and lipids using gels made from Koshihikari grown in either Australia or Japan. Immediately after cooking, cooling from 60 to 40 degrees C had a minimal effect on firmness, but cooling to 20 degrees C led to significantly firmer gels. Storing the gels at low temperatures did not have an additional effect on the firmness as compared with storing the gels at 20, 40, or 60 degrees C. The removal of proteins led to significantly softer gels at all storage treatments but did not affect the change in firmness on cooling. The removal of lipids increased the rate of retrogradation and the firmness of gels significantly for all treatments. Koshihikari grown in Japan retrograded much less than Koshihikari grown in Australia. The amount of amylose that could be washed from gels made from Australian flour was much greater than for gels made from Japanese flour. After storage, only low molecular weight amylose chains were released from the gel and only after rewarming them to 60 degrees C. Despite the fact that flours from both origins were 18% amylose, the amount of long amylose chains that were complexed with lipids was much greater for the Japanese rice, and the unavailability of the complexed long amylose chains explained the lack of retrogradation in the Japanese rice. Once the long chains were released from amylose-lipid complexes, the Japanese rice retrograded. Thus, the environmental factor affecting retrogradation in this variety is type or amount of lipids synthesized, and the degree of retrogradation was determined by the availability of long chains of amylose.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-8561
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5182-90
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Environmental factors that affect the ability of amylose to contribute to retrogradation in gels made from rice flour.
pubmed:affiliation
NSW Department of Primary Industries, Yanco Agricultural Institute, Yanco 2703, Australia.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't