Estresse inicial por baixo oxigênio seguido do armazenamento em atmosfera controlada de maçãs 'Royal Gala'

Abstract

RESUMO -O objetivo do presente trabalho foi avaliar a aplicação de estresse inicial por baixo oxigênio e 1-metilciclopropeno (1-MCP) sobre a manutenção de qualidade de maçãs 'Royal Gala' armazenadas em atmosfera controlada (AC). Para tanto, um lote com 50% dos frutos foi tratado com 1-MCP (625 ppb) e destes, a metade, juntamente com a metade daqueles sem aplicação de 1-MCP, foram submetidos a um estresse por baixo oxigênio (0,3 kPa por sete dias), antes de serem armazenados por sete meses, a 0,5 °C e nas seguintes condições de AC: 1,2 kPa O 2 + 2,0 kPa CO 2 ; 1,0 kPa O 2 + 2,0 kPa CO 2 ; 0,8 kPa O 2 + 1,0 kPa CO 2 ; 0,6 kPa O 2 + 1,0 kPa CO 2 e 0,5 kPa O 2 + 1,0 kPa CO 2 . Após o armazenamento mais sete dias de exposição a 20 °C foram realizadas análises de qualidade nos frutos. Os resultados evidenciam que o estresse inicial por baixo O 2 não é eficiente em manter a qualidade, inclusive aumentando a ocorrência de distúrbios fisiológicos e podridões. Não houve grande diferença na eficiência das condições de AC utilizadas neste trabalho sobre a conservação da qualidade dos frutos. A aplicação de 1-MCP não melhorou a preservação da qualidade dos frutos armazenados em ultrabaixo O 2 , como verificado nas menores pressões parciais (< 1,0 kPa) utilizadas no presente trabalho. Palavras-chave: Malus domestica. Etileno. 1-metilciclopropeno (1-MCP).ABSTRACT -The aim of this work was to evaluate the application of initial low oxygen stress and 1-methylcyclopropene (1-MCP) on quality maintenance of Royal Gala apples, when stored in a controlled atmosphere (CA). In order to do this, a lot of 50 % of the fruit was treated with 1-MCP (625 ppb) and one half of these, together with half of the fruit which did not receive the application of 1-MCP, were subjected to low oxygen stress (0.3 kPa for seven days) before being stored for seven months at 0.5 °C under the following CA conditions: 1.2 kPa O 2 + 2.0 kPa CO 2 ; 1.0 kPa O 2 + 2.0 kPa CO 2 ; 0.8 kPa O 2 + 1.0 kPa CO 2 ; 0.6 kPa O 2 + 1.0 kPa CO 2 e 0.5 kPa O 2 + 1.0 kPa CO 2 . After storage, and following a further seven days at 20 °C, analyses of fruit quality were carried out. The results show that initial low oxygen stress is not effective in maintaining quality, beyond increasing the occurrence of physiological disorders and decay. There was no big difference in the efficiency of the CA conditions used in this study on the conservation of fruit quality. The application of 1-MCP did not improve quality maintenance in fruit stored under ultralow oxygen, as seen at the lowest partial pressures (<1.0 kPa) used in this work.

Dynamic controlled atmosphere and ultralow oxygen storage on ‘Gala’ mutants quality maintenance

“…The higher ethylene production by these fruits has a relation with elevated oxygen levels adopted during CA storage (1.2 kPa). This behavior was also found by other researchers comparing ULO and CA Both, Brackmann, Weber, et al, 2014;Brackmann et al, 2013;Weber et al, 2013). In the two years, fruits stored under DCA-CF and ULO did not differ over six days of shelf life, which indicate that ULO has the same effect as DCA-CF on ethylene production.…”

“…'Royal Gala' apples stored under CA showed the highest ACC oxidase enzyme activity, fruits stored under DCA-CF showed an intermediary activity and ULO the lowest. Another research with 'Royal Gala' apples also found lower ACC oxidase enzyme activity in fruits stored under ULO, compared to CA (Both, Brackmann, Weber, et al, 2014). The lower ACC oxidase activity may be related to the higher ethanol concentration in this treatment group over the two years.…”

“…The higher decay incidence by fruits of these treatments may be a result of too long a time under the initial low oxygen (near to 0.00 kPa) conditions, until chlorophyll fluorescence emission spikes. Early researchers also found a significant increase in decay incidence by ILOs application in 'Royal Gala' apples (Both, Brackmann, Weber, et al, 2014;Brackmann et al, 2013).…”

“…Approximately 1.5 kg of fruits were put into 5 l hermetically closed containers for about 2 h. Thereafter, two samples of 1 ml were taken from the container and injected into a gas chromatograph (Varian Ò , model Star 3400CX), according methodology proposed by Both, Brackmann, Weber, Anese, and Thewes (2014).…”

Storage potential of ‘SCS426 Venice’ apples under different storage technologies

“…The effects of storage of fruits under CA on the reduction of ethylene synthesis and action (BOTH et al, 2014) and respiration are well known (STEFFENS et al, 2007), as well as the effect of 1-MCP on ethylene inhibition (DE MARTINO et al, 2006). 1-MCP can also indirectly reduce the respiratory rate of fruits by inhibiting the autocatalytic ethylene production (WANG;SUGAR, 2013).…”