Injúrias mecânicas e processamento mínimo de goiabas: fisiologia e qualidade pós-colheita
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Data
2002-02-04
Autores
Mattiuz, Ben-Hur [UNESP]
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Universidade Estadual Paulista (Unesp)
Resumo
Avaliou-se o efeito das injúrias mecânicas por impacto, compressão ou corte, e do processamento mínimo na fisiologia de goiabas 'Paluma' e 'Pedro Sato'. Na injúria por impacto, os frutos foram deixados cair, em queda livre, de uma altura de 1,20 m, sofrendo dois impactos, em lados opostos da porção equatorial do fruto. Na injúria por compressão, os frutos foram submetidos a um peso de 29,4 N, por 15 minutos. Para a injúria por corte, foram efetuados dois cortes, longitudinalmente, de 30 mm de comprimento por 2 mm de profundidade. Os frutos foram armazenados sob condições de ambiente (23,4l1 °C, 62l6 %UR). No processamento mínimo, frutos no estádio de vez foram descascados, cortados longitudinalmente ao meio, eliminando-se as sementes. Após enxágüe, foram embalados em contentores de tereftalato de polietileno e armazenados a 3 °C. Os frutos da 'Paluma' apresentaram-se significativamente mais resistentes que os da 'Pedro Sato' à injúria por impacto. O estresse físico causado por esta injúria produziu um colapso interno nos lóculos dos frutos e a área injuriada mostrou-se mais escurecida e com menor cromaticidade que as áreas não injuriadas, de ambas as cultivares. Os frutos injuriados sempre produziram maior quantidade de CO2 que os dos controles, sem que se detectasse a ocorrência de pico respiratório. Os teores de sólidos solúveis totais, açúcares redutores, acidez total titulável e ácido ascórbico dos frutos injuriados apresentaram-se menores que os dos controles, ao longo do período de armazenamento. No produto minimamente processado, a goiaba possibilitou o rendimento de 51%. A embalagem evitou a perda da massa fresca e possibilitou a modificação da atmosfera no seu interior, com manutenção dos níveis de O2 e CO2 em 16,60 % e 1,95 %, respectivamente. A coloração foi mantida e o conteúdo de ácido ascórbico reduziu-se, ao longo do período... .
The present study examined the effects of mechanical injuries due to impact, compression and cuts, and of minimal processing in the physiology of guava fruit 'Paluma' and 'Pedro Sato.' In impact injury, fruit were allowed to fall freely from a height of 1.2 m, subjecting them to two impacts, on opposites sides of the equatorial portion of the fruit. In compression injury, fruit were submitted to a weight of 29.4 N for 15 min. For the cut injury, two longitudinal cuts were made, 30 mm in length and 2 mm deep. Fruit were stored under ambient conditions (23.4l1 °C, 62l6 % RH). In minimal processing, fruit at the stage of harvesting were cut longitudinally in the equatorial region and seeds were removed. After rinsing, fruit were packaged in polyethylene terephthalate containers and stored at 3 °C. 'Paluma' fruit showed a significantly greater resistance to impact injury compared to the Pedro Sato variety. Physical stresses associated with this type of injury produced an internal collapse of fruit locules. The injured area showed more darkening and less color development compared to non-injured areas, for both varieties. Bruised fruits usually produced a higher amount of CO2 compared to controls, without detecting the occurrence of a respiratory peak. Levels of total soluble solids, reducing sugars, total titratable acidity and ascorbic acid for bruised fruit were lower than those for controls, during the storage period. In the minimally processed product, guava fruit allowed a yield of 51%. Packaging prevented the loss of fresh mass and allowed the modification of the air in its interior. Levels of O2 and CO2 were maintained at 16.60 % and 1.95 %, respectively. Color remained about the same and ascorbic acid content was reduced, during the storage period. The content of total soluble solids and total titratable acid was not affected... (Complete abstract, click eletronic address below).
The present study examined the effects of mechanical injuries due to impact, compression and cuts, and of minimal processing in the physiology of guava fruit 'Paluma' and 'Pedro Sato.' In impact injury, fruit were allowed to fall freely from a height of 1.2 m, subjecting them to two impacts, on opposites sides of the equatorial portion of the fruit. In compression injury, fruit were submitted to a weight of 29.4 N for 15 min. For the cut injury, two longitudinal cuts were made, 30 mm in length and 2 mm deep. Fruit were stored under ambient conditions (23.4l1 °C, 62l6 % RH). In minimal processing, fruit at the stage of harvesting were cut longitudinally in the equatorial region and seeds were removed. After rinsing, fruit were packaged in polyethylene terephthalate containers and stored at 3 °C. 'Paluma' fruit showed a significantly greater resistance to impact injury compared to the Pedro Sato variety. Physical stresses associated with this type of injury produced an internal collapse of fruit locules. The injured area showed more darkening and less color development compared to non-injured areas, for both varieties. Bruised fruits usually produced a higher amount of CO2 compared to controls, without detecting the occurrence of a respiratory peak. Levels of total soluble solids, reducing sugars, total titratable acidity and ascorbic acid for bruised fruit were lower than those for controls, during the storage period. In the minimally processed product, guava fruit allowed a yield of 51%. Packaging prevented the loss of fresh mass and allowed the modification of the air in its interior. Levels of O2 and CO2 were maintained at 16.60 % and 1.95 %, respectively. Color remained about the same and ascorbic acid content was reduced, during the storage period. The content of total soluble solids and total titratable acid was not affected... (Complete abstract, click eletronic address below).
Descrição
Palavras-chave
Goiaba - Processamento - Qualidade, Goiaba - Fisiologia pós-colheita, Psidium guajava, minimally processed
Como citar
MATTIUZ, Ben-Hur. Injúrias mecânicas e processamento mínimo de goiabas: fisiologia e qualidade pós-colheita. 2002. v, 120 f. Tese (doutorado) - Universidade Estadual Paulista, Faculdade de Ciências Agrárias e Veterinárias, 2002.