{"created":"2021-03-01T06:43:59.840712+00:00","id":8568,"links":{},"metadata":{"_buckets":{"deposit":"dc885288-6c9f-484d-beec-02f49e4a235c"},"_deposit":{"id":"8568","owners":[],"pid":{"revision_id":0,"type":"depid","value":"8568"},"status":"published"},"_oai":{"id":"oai:tsukuba.repo.nii.ac.jp:00008568","sets":["3:233:265"]},"author_link":["35326"],"item_12_biblio_info_6":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2004","bibliographicIssueDateType":"Issued"}}]},"item_12_date_granted_46":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2004-03-25"}]},"item_12_degree_grantor_44":{"attribute_name":"学位授与大学","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"筑波大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"University of Tsukuba"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"12102","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_12_degree_name_43":{"attribute_name":"取得学位","attribute_value_mlt":[{"subitem_degreename":"博士（農学）"},{"subitem_degreename":"Doctor of Philosophy in Agricultural Science"}]},"item_12_description_4":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Nowadays, in China, the problem of protein inadequacy still exists. To solve this problem,\nlow cost, good quality vegetable proteins are considered to be one of the best choices. Among\nthem, as a good vegetable protein resource, soybean has aroused the attention of many\nresearchers. Tofu, a kind of soybean product, was invented in ancient time in China and\nnowadays, it is still a popular daily dish in some Asian countries like China, Japan, Korea, etc\nand is considered as a good vegetable protein resource. For the traditional food culture and the\nstyle of Chinese dishes, Chinese prefer hard tofu. At present, the production of tofu is mainly\ndone by small-scale factories with handmade way. Such kind of factories can produce hard\ntofu meeting the palatability of Chinese consumers. But, the shelf life of tofu is very short, in\nsummer, only half a day, which limits the distribution of tofu. At the same time, the labor\ndensity is higher, the quality control of tofu is mainly by experiences and a uniform quality is\ndifficult to be realized. In 1980s’, some industrial lines were imported. But, such kind of\nindustrial production line uses glucono-delta-lactone (GDL) as coagulant. Tofu produced by\nthis way is somewhat acidic, which is not preferred by consumers, and the texture of tofu is\nvery soft, which is not suitable for most of the Chinese dishes. Lack of information on\nproducing hard tofu by industrial line limit the industrial production of hard tofu in China.\nBased on the present situation of hard tofu production in China, this study takes the\nimprovement of tofu texture in China as the objective.\nTo improve the texture of tofu, firstly, a proper evaluation method for the texture of tofu is\nnecessary. Stress-strain, stress relaxation and creep tests were conducted. Results showed that\nparameters from stress relaxation and creep behaviors analyzed by using viscoelastic models\n(taking Maxwell model, serialized by a Spring model and Dashpot model, and Vigot model,\nparalleled by a Spring model and a Dashpot model as primary models) can reflect both the\nviscous and elastic changes of tofu with different coagulants and protein concentrations. It\nwas suggested that this viscoelastic evaluation method was effective for the texture evaluation\nof tofu.\nAfter determining the proper texture evaluation method for tofu, in this study, the effects of\nsoymilk concentration (protein) concentration, types and concentration of different coagulants\n(CaSO4, GDL, MgCl2) on the texture of tofu and the effects of okara addition on the texture of\ntofu were investigated. For the improvement of tofu texture in China, from the view of protein\nconcentration, types and concentration of coagulants, the addition of okara, following\nconclusions were drawn:\n(1) A higher soymilk concentration (protein concentration) can lead to a harder tofu. The\nviscosity of soymilk also increased with increasing the protein concentration. A too high\nviscosity might cause the difficulties of pipe transportation. In industrial practice, the\nbalance between protein concentration and a proper viscosity should be considered.\n(2) Different coagulants showed different properties to the tofu production. For CaSO4 and\nGDL, increasing the amount of coagulant resulted in a harder tofu. MgCl2 showed a\nnarrow range of optimal concentrations and too high concentration of MgCl2 caused a\nductile break of tofu. When at the same concentration of protein, GDL and MgCl2 can\ninduce harder tofu than CaSO4. The reaction of MgCl2 with soy protein is rapider than\nthat of GDL and CaSO4.\n(3) It is possible to add paste-like okara to soymilk for the production of tofu. At a certain\nrange, the texture of tofu was not significantly affected by the addition of okara. CaSO4\nshowed different response to the addition of okara comparing with GDL. 15% addition of\nokara increased the break stress of CaSO4-coagulated tofu while the addition of okara\ndecreased the break stress of GDL-tofu.\nBased on the results in this study, it can be suggested that for industrial hard tofu\nproduction in China, using properly high concentration of soymilk, mixture of coagulants,\nsuch as CaSO4 with MgCl2, GDL with MgCl2, increasing the concentration of coagulants like\nCaSO4 and GDL and adding okara can be reasonable alternatives.","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_12_description_45":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_description":"2003","subitem_description_type":"Other"}]},"item_12_description_5":{"attribute_name":"内容記述","attribute_value_mlt":[{"subitem_description":"Includes bibliographical references","subitem_description_language":"en","subitem_description_type":"Other"}]},"item_12_dissertation_number_47":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_dissertationnumber":"甲第3531号"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Cheng, Yongqiang","creatorNameLang":"en"},{"creatorName":"程, 永強","creatorNameLang":"ja"}],"nameIdentifiers":[{"nameIdentifier":"35326","nameIdentifierScheme":"WEKO"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2013-12-18"}],"displaytype":"detail","filename":"A3531.pdf","filesize":[{"value":"168.5 kB"}],"format":"application/pdf","mimetype":"application/pdf","url":{"objectType":"abstract","url":"https://tsukuba.repo.nii.ac.jp/record/8568/files/A3531.pdf"},"version_id":"9a37b990-87be-4daa-96c3-9b8ce012289e"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2013-12-18"}],"displaytype":"detail","filename":"1.pdf","filesize":[{"value":"664.2 kB"}],"format":"application/pdf","mimetype":"application/pdf","url":{"objectType":"fulltext","url":"https://tsukuba.repo.nii.ac.jp/record/8568/files/1.pdf"},"version_id":"b1ec2c00-926a-4a56-850d-728d352d76e2"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"Improvement of tofu texture in China","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Improvement of tofu texture in China","subitem_title_language":"en"}]},"item_type_id":"12","owner":"1","path":["265"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2007-07-25"},"publish_date":"2007-07-25","publish_status":"0","recid":"8568","relation_version_is_last":true,"title":["Improvement of tofu texture in China"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-01T01:03:54.583689+00:00"}