Mechanical Behavior Of 'niagara Rosada' Grape Berry Detachment

The 'Niagara Rosada' grape is the main Brazilian table grape belonging to the Labrusca family. It develops medium, cylindrical and compact bunches with berries presenting a pinkish skin and a foxy flavor that is valued in the Brazilian market. These berries are tender and have a pedicel-berry connection provided by the vascular bundles and surrounding skin. This cultivar is very susceptible to berry drop mainly caused by vibration and senescence. The objective of this study was to evaluate the temporal mechanical behavior of the pedicel-berry detachment, using resistance indexes extracted from traction force-deformation curves. Test results showed two different detachment types. In the first one, which exhibited higher average resistance, a considerable portion of the vascular bundle came out attached to the pedicel and in the second type; the vascular bundle was retained inside the berry. The proposed indexes based on maximum detachment force, force at 0.2; 0.5; 1.0 and 1.2 mm, and maximum force to corresponding deformation ratio did not discriminate the senescence of the berry.31611151122Barnes, K.K., Detachment characteristics of lemons (1969) Transactions of the ASAE, St. Joseph, 12 (1), pp. 41-45Regulamento Técnico de Identidade e de Qualidade para a Classificação dos produtos a seguir: abacaxi, uva fina de mesa, uva rústica (2002), p. 2. , BRASIL. Instrução Normativa n. 1, de 1o de fevereiro de 2002. Seção 1Chitarra, M.I.F., Chitarra, A.B., Pós-colheita de frutos e hortaliças: fisiologia e manuseio (1990), p. 320. , Lavras: ESALFAEPEMapas de produções agrícolas do estado de São Paulo (2001), CATI - COORDENADORIA DE ASSISTÊNCIA TÉCNICA INTEGRAL. CampinasChen, F.H., Yu, X., Zhang, W.Y., Tan, D.Y., Study on relationship between pedicel structure and berry abscission of Xinjiang Wuhebai grape cultivars (2000) Journal of Xinjiang Agricultural University, Xinjiang, 23, pp. 44-48Ferraz, A.C.O., Sargent, A., Fox, A.J., A nondestructive method for measuring firmness of blueberry fruit (2001) Proceedings Florida Horticulture Society, 114, pp. 138-142Gomes, D., Efeito da vibração na qualidade da uva Niagara Rosada (2006), 2006. Dissertação (Mestrado) - Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, CampinasMohsenin, N.N., Physical Properties of plants and Animals Material (1970), 1, p. 734. , New York: Gordon and breach Science PublisherRibéreau Gayon, J., Peynaud, E., Traitéd'ampélologie: sciences et techniques de la vigne: biologie de la vigne (1980), 1, pp. 116-130. , sols de vignobles Paris: DunodSantos, A.H.P., Ferraz, A.C.O., Dal Fabro, I.M., Força de destacamento da vagem do pedúnculo do amendoim In: CONGRESSO DE ENGENHARIA AGRÍCOLA, 23., Campinas. AnaisSnedecor, G.W., Statistical methods (1980), 7th ed. Iowa State UniversityVieira, S., Estatística experimental (1999), p. 185. , 2.ed. São Paulo: Atlas. (Técnica da ANOVA