Water binding to biopolymers in different cereals and legumes: Proton NMR relaxation, dielectric and water imbibition studies

Ratkovic, S; Pissis, P

dc.contributor.author	Ratkovic, S	en
dc.contributor.author	Pissis, P	en
dc.date.accessioned	2014-03-01T01:13:30Z
dc.date.available	2014-03-01T01:13:30Z
dc.date.issued	1997	en
dc.identifier.issn	0022-2461	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12515
dc.subject	Chemical Composition	en
dc.subject	Dielectric Properties	en
dc.subject	Indexation	en
dc.subject	Maize	en
dc.subject	Protein Content	en
dc.subject	Relaxation Time	en
dc.subject	Dry Matter	en
dc.subject	Water Content	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Carbohydrates	en
dc.subject.other	Composition effects	en
dc.subject.other	Dielectric properties	en
dc.subject.other	Grain (agricultural product)	en
dc.subject.other	Hydration	en
dc.subject.other	Lipids	en
dc.subject.other	Macromolecules	en
dc.subject.other	Magnetic relaxation	en
dc.subject.other	Nuclear magnetic resonance	en
dc.subject.other	Protons	en
dc.subject.other	Water	en
dc.subject.other	Thermally stimulated depolarization currents (TSDC) method	en
dc.subject.other	Water imbibition	en
dc.subject.other	Biopolymers	en
dc.title	Water binding to biopolymers in different cereals and legumes: Proton NMR relaxation, dielectric and water imbibition studies	en
heal.type	journalArticle	en
heal.identifier.primary	10.1023/A:1018678029109	en
heal.identifier.secondary	http://dx.doi.org/10.1023/A:1018678029109	en
heal.language	English	en
heal.publicationDate	1997	en
heal.abstract	Proton NMR relaxation time (T-1), dielectric properties by means of the thermally stimulated depolarization currents (TSDC) method, and water imbibition were measured in cereal and legume grains (wheat, triticale, maize, pea, chick pea, horsebean, white lupin, lentil and beans) having different chemical composition (proteins, carbohydrates, lipids). T-1 versus water content in the range 0.05-1.40 g water/g dry matter showed characteristic V-shaped curves with a sharp or a broad minimum depending on the species. Water content at T-1 min was in high positive correlation with protein content of the grains (r=0.90) and in high negative correlation with soluble carbohydrates (r=-0.92), while lipids gave a very low correlation (r=0.38). The water content at T-1 min (0.18-0.47 g water/g dry matter) was assigned to a primary hydration sphere around the macromolecules, since, when T-1 was plotted versus per cent maximum hydration, the T-1 min values for all grains fell between 25-30% of maximum hydration. The extrapolated value for zero protein content was 0.08 g water/g dry matter, which coincided with data in the literature for the water monolayer on starch. The TSDC measurements enabled us to determine the amount of tightly (irrotationally) bound water at primary hydration sites to 0.18 +/- 0.02 g water/g dry matter for beans, pea and chickpea, and, tentatively, to about 0.10 g water/g dry matter for wheat. Water imbibition data for 11 cereal and legume species gave total water hydration capacity in the range a=0.44-1.82 g water/g dry matter. This value divided by the water content of the primary hydration sphere (swelling index) was also in high positive correlation with the protein content of the grains (r=0.84).	en
heal.publisher	CHAPMAN HALL LTD	en
heal.journalName	Journal of Materials Science	en
dc.identifier.doi	10.1023/A:1018678029109	en
dc.identifier.isi	ISI:A1997XD82700035	en
dc.identifier.volume	32	en
dc.identifier.issue	11	en
dc.identifier.spage	3061	en
dc.identifier.epage	3068	en