title: Influence of germination conditions on malting potential of low and normal amylose paddy and changes in enzymatic activity and physico chemical properties.
abstract: Malting potential of two rice cultivar i.e. low (12.5%) (LR) and normal (20.2%) amylose paddy (NR) were evaluated under different germination conditions (25-40°C for 120h). Based on malting potential, 30 and 35°C germination temperatures were found suitable. Enzymes (amylolytic and α-amylase) activity increased at both temperatures for LR and NR whereas NR exhibited higher activity. NR malted rice showed higher starch degradation (64 and 74 times) when compared to LR (58 and 62 times) at 30 and 35°C respectively leading to formation of reducing sugar and lowering of viscosity. During germination of LR and NR significant morphological and structural changes were observed as evident from pin-holes and eroded surface in micrographs, decreased % crystallinity and FTIR peaks. Outcome of present study concluded that the amylose amylopectin ratio played an important role during germination and NR paddy was found more suitable for malting at 30 and 35°C.
authors.affiliation: Department of Food Engineering and Technology, Tezpur University, Tezpur, Assam, India.
authors.forename: Dipsikha
authors.initials: D
authors.lastname: Kalita
authors.affiliation: Department of Chemical Science, Tezpur University, Tezpur, Assam, India.
authors.forename: Bipul
authors.initials: B
authors.lastname: Sarma
authors.affiliation: Department of Food Engineering and Technology, Tezpur University, Tezpur, Assam, India. Electronic address: brijesh@tezu.ernet.in.
authors.forename: Brijesh
authors.initials: B
authors.lastname: Srivastava
mesh_terms: D000687:Amylopectin / Q000737:chemistry; D000688:Amylose / Q000737:chemistry*; D002241:Carbohydrates; D018525:Germination / Q000502:physiology*; D012275:Oryza / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D000688:Amylose; D000687:Amylopectin; D000516:alpha-Amylases
keywords: Alpha amylase activity; Amylolytic activity; Germination potential; Germination temperature; Morphological changes; Reducing sugar; Starch degradation