title: Detailed analysis of seed coat and cotyledon reveals molecular understanding of the hard-to-cook defect of common beans (Phaseolus vulgaris L.).
abstract: The hard-to-cook (HTC) defect in legumes is characterized by the inability of cotyledons to soften during the cooking process. Changes in the non-starch polysaccharides of common bean seed coat and cotyledon were studied before and after development of the HTC defect induced by storage at 35°C and 75% humidity for 8months. Distinct differences in the yields of alcohol insoluble residues, degree of methoxylation (DM), sugar composition, and molar mass distribution of non-starch polysaccharides were found between the seeds coat and cotyledons. The non-starch polysaccharide profiles, both for seed coats and cotyledons, significantly differed when comparing HTC and easy-to-cook (ETC) beans. In conclusion, differences in the structure, composition and extractability of non-starch polysaccharides between the ETC and HTC beans confirmed the significant role of pectin polysaccharides in interaction with divalent ions in the HTC development, which consequently affect their cooking behaviors.
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Science (CAAS), Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, China; Laboratory of Food Technology, Department of Microbial Molecular Systems (M2S), Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22 Box 2457, Heverlee 3001, Belgium. Electronic address: yijianyong515@126.com.
authors.forename: Jianyong
authors.initials: J
authors.lastname: Yi
authors.affiliation: Laboratory of Food Technology, Department of Microbial Molecular Systems (M2S), Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22 Box 2457, Heverlee 3001, Belgium; Department of Food Science, Faculty of Agriculture, Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-00200, Nairobi, Kenya.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Njoroge
authors.affiliation: Department of Food Science, Faculty of Agriculture, Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-00200, Nairobi, Kenya.
authors.forename: Daniel N
authors.initials: DN
authors.lastname: Sila
authors.affiliation: Department of Food Science, Faculty of Agriculture, Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-00200, Nairobi, Kenya.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Kinyanjui
authors.affiliation: Laboratory of Food Technology, Department of Microbial Molecular Systems (M2S), Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22 Box 2457, Heverlee 3001, Belgium.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Christiaens
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Science (CAAS), Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, China.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Bi
authors.affiliation: Laboratory of Food Technology, Department of Microbial Molecular Systems (M2S), Leuven Food Science and Nutrition Research Center (LFoRCe), KU Leuven, Kasteelpark Arenberg 22 Box 2457, Heverlee 3001, Belgium. Electronic address: marc.hendrickx@biw.kuleuven.be.
authors.forename: Marc E
authors.initials: ME
authors.lastname: Hendrickx
mesh_terms: D002413:Cations, Divalent / Q000737:chemistry; D003296:Cooking / Q000379:methods*; D018548:Cotyledon / Q000737:chemistry*; D006244:Hardness; D006813:Humidity; D010368:Pectins / Q000737:chemistry; D027805:Phaseolus / Q000737:chemistry*; D011134:Polysaccharides / Q000032:analysis / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D011134:Polysaccharides; D010368:Pectins
keywords: Calcium; Common beans; Extractability; Molar mass; Neutral sugar; Pectin