title: Starch characterization in seven raw, boiled and roasted chestnuts (Castanea sativa Mill.) cultivars from Portugal.
abstract: Changes occurring in seven chestnut (Castanea sativa sp.) cultivars, caused by boiling and roasting, on starch content, cell and starch granules dimension were evaluated, and morphological changes were characterized by scanning electron microscopy. Three clear patterns of variation were detected after processing, namely: i) decrease of starch content with processing; ii) starch increase with the applied treatments; iii) increase of starch with boiling and decrease with roasting. Starch granules of raw chestnuts presented round, oval or elliptical form, external smooth surface and eccentric hilum, with rather ellipsoid-shaped growth rings. Processing resulted in modifications of the granules, with fusion of individual granules, and gelatinization taking place with the formation of elongated clusters. The present results indicate that boiling and roasting, besides changing the starch content of chestnut, causes important modifications in the starch granules, which can affect the sensory, rheological and chemical characteristics of chestnuts.
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5000-801 Vila Real, Portugal.
authors.forename: A P
authors.initials: AP
authors.lastname: Silva
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5000-801 Vila Real, Portugal.
authors.forename: I
authors.identifier: 0000-0002-0866-953X
authors.initials: I
authors.lastname: Oliveira
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5000-801 Vila Real, Portugal.
authors.forename: M E
authors.initials: ME
authors.lastname: Silva
authors.affiliation: CECAV - Animal and Veterinary Research Center, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal.
authors.forename: C M
authors.initials: CM
authors.lastname: Guedes
authors.affiliation: Direcção Regional de Agricultura de Trás-os-Montes, Delegação Regional do Nordeste Transmontano, Av. Humberto Delgado, 5300-167 Bragança, Portugal.
authors.forename: O
authors.initials: O
authors.lastname: Borges
authors.affiliation: Cooperativa Agrícola de Penela da Beira, Penela da Beira, 3630-262 Penedono, Portugal.
authors.forename: B
authors.initials: B
authors.lastname: Magalhães
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5000-801 Vila Real, Portugal.
authors.forename: B
authors.initials: B
authors.lastname: Gonçalves
keywords: Boiling; Castanea sativa; Granule morphology; Roasting; Starch