Environmental variables in packing houses and their effects on the quality of grapes

Abstract

A B S T R A C TThe aim of this study was to characterize the thermal environment in the selection and packing areas of a packing house and its effects on the quality of table grapes produced in the São Francisco Valley, Brazil. The thermal environment was monitored during the winter and summer seasons. The highest value of air temperature (Tair) and the lowest relative humidity (RH) observed in the packing house were 35 °C and 40.0%, respectively, obtained during the summer, for 8 h. After observing the thermal environment data of the packing house, simulations were performed to evaluate the effect of the ideal environmental storage conditions and observed thermal conditions on the postharvest quality of "Thompson" grapes. Grapes were harvested and stored directly at the ideal temperature and RH of 0 °C and 90%, respectively, or previously exposed to a temperature of 35 °C and RH of 40% for 8 h, the thermal environment observed in the evaluated packing house, followed by storage at 0 °C and 90% RH. Fruit exposure to high temperature and low RH before the ideal storage conditions resulted in higher loss of berry firmness and weight, along with increased soluble solids and dry matter content of rachis and berry. Based on these results, the environmental conditions observed in the packing house result in berry dehydration, which accelerates the loss of fruit quality during storage.Variáveis ambientais em 'packing houses' e efeitos sobre a qualidade de uvas R E S U M O Objetivou-se caracterizar o ambiente térmico da área de seleção e embalagem de um 'packing house' e seus efeitos sobre a qualidade de uvas de mesa produzidas no Vale do São Francisco. O ambiente térmico foi monitorado durante as estações de inverno e verão. Os maiores valores de temperatura do ar (Tar) e menores de umidade relativa do ar (UR) observados no packing house, foram 35 °C e 40,0%, respectivamente, obtidos durante o verão, por 8 h. Após a observação dos dados do ambiente térmico do packing house, foram feitas simulações para avaliar o efeito de condições ambientais ideais de armazenamento e das condições térmicas observadas sobre a qualidade pós-colheita de uvas 'Thompson' . Neste contexto, uvas foram colhidas e diretamente armazenadas em temperatura e umidade ideais (0 °C e 90%), ou foram expostas previamente a uma temperatura do ar de 35 °C e umidade relativa do ar de 40% por 8 h, simulando o ambiente térmico observado no packing house avaliado, sendo posteriormente armazenada a 0 °C e 90%. A exposição dos frutos ao ambiente observado no packing house resultou em maiores perdas de firmeza e peso de bagas, assim como aumentou os teores de sólidos solúveis e matéria seca do engaço e da baga. De acordo com os resultados obtidos, as condições ambientais observadas no packing house resultam na desidratação das bagas, acelerando a perda de qualidade dos frutos durante o armazenamento.

Development of an artificial fruit prototype for monitoring mango skin and flesh temperatures during storage and transportation

“…Refrigerated containers and cold rooms in packing houses usually have three thermocouples in straight line to monitor air temperature and relative humidity at a single height, which is not consistent with the homogeneity of air temperature and relative humidity spatialization in the environment. Besides poor distribution of sensors inside the packages, pallet position and height can cause cold injuries or acceleration of ripening (Wu et al, 2018;Defraeye et al, 2016;Dehghannya et al, 2012;Dacanal et al, 2018;Vasconcelos et al, 2017Vasconcelos et al, , 2018Vasconcelos et al, 2019).…”