ABSTRACT Carnation (Dianthus caryophyllus) is one of the most important and popular cut flowers for the ornamental industry. However, it has a short decorative life, being water loss one of the main challenges. Water loss leads the petals to wither with a consequent loss of its commercial value. One of the techniques used in postharvest technology is the use of coatings and films, which interfere in gas exchange and water loss, maintaining the quality of cut flowers. The current study investigated the effects of a natural coating based on hydroxypropyl methylcellulose (HPMC) at 5% and beeswax (BW) in cut carnation flower cv. Delphi stored at 20°C and 70% RH. The application of HPMC + 40% BW treatment in flowers resulted in 30% higher fresh weight, 17% higher relative water content (RWC) and 80% higher flower opening compared to untreated flowers. The shelf life of untreated and HPMC + 40% BW carnations was 7 and 12 days, respectively, allowing a shelf-life extension of up to five days.

RESUMO O cravo (Dianthus caryophyllus) é uma das flores mais importantes e populares na indústria ornamental. No entanto, apresenta curta vida de prateleira, sendo a perda de água um dos principais problemas, resultando em murcha das pétalas e consequente perda de valor comercial. Uma das técnicas utilizadas na pós-colheita é a utilização de películas e filmes, que interferem nas trocas gasosas e na perda de água, conservando a qualidade das flores de corte. Este estudo investigou os efeitos da película natural à base de hidroxipropilmetilcelulose (HPMC) a 5% e cera de abelha (CA) em flores de corte de cravo cv. Delphi armazenadas a 20°C e 70% HR. As flores tratadas com HPMC + 40% CA apresentaram incremento de 30% na massa fresca, 17% no conteúdo relativo de água (CRA) e 80% na abertura floral. A vida útil dos cravos do controle e do HPMC + 40% CA foi de 7 e 12 dias, respectivamente, prolongando a vida de prateleira por até cinco dias.

RESUMO As flores de corte se deterioram muito rapidamente e necessitam de tecnologias pós-colheita para aumentar a durabilidade, que é normalmente em torno de 8 dias. Devido às escassas informações relacionadas à fisiologia pós-colheita de flores de Alstroeméria, a presente pesquisa teve como objetivo verificar qual a melhor dose de 1-metilciclopropeno (1-MCP) na conservação pós-colheita de inflorescências de Alstroemeria cv. Ajax, considerando os fatores associados à senescência floral e perda da vida decorativa. As hastes foram submetidas a quatro doses de 1-MCP (0; 100; 250; 500 ppb), posteriormente foram colocadas em recipientes com água destilada e armazenadas em temperatura de ambiente (22 ºC). Os tratamentos foram realizados em triplicata contendo três hastes por repetição. As avaliações foram realizadas a cada três dias perfazendo um total de 12 dias de armazenamento. Foi realizado um teste de F, e as médias comparadas pelo teste de Tukey (P≤0,05). Entre os tratamentos aplicados a dose de 500 ppb de 1-MCP reduziu a perda de água das hastes de alstroeméria durante o período de armazenamento, mantendo as pétalas túrgidas e os níveis de carotenoides e antocianinas altos, entretanto, isso não foi suficiente para manter a qualidade decorativa das flores, uma vez que o 1-MCP não resolveu os problemas de amarelecimento das folhas e abertura floral, que são importantes características para sua comercilização.

ABSTRACT Cut flowers deteriorate quickly and require postharvest technologies to increase their durability, which is usually around 8 days. Due to the scarce information related to postharvest physiology of Alstroemeria cut flowers, this study aimed to verify the best dose of 1-methylcyclopropene (1-MCP) to the postharvest conservation of inflorescences of Alstroemeria cv. Ajax, considering the factors associated with floral senescence and loss of the decorative life. The stems were submitted to four doses of 1-MCP (0; 100; 250; 500 ppb), then placed in containers with distilled water and stored at room temperature (22 ºC). The treatments were performed in triplicate containing three stems per replicate. The evaluations were performed every three days for a total of 12 days of storage. An F test was conducted, and the means were compared by the Tukey test (p≤0.05). Among the applied treatments the dose of 500 ppb of 1-MCP reduces the loss of water of the stems of alstroemerias during the storage period, keeping the petals turgids and the levels of carotenoids and anthocyanins high, however, this was not enough to keep the decorative quality of the flowers, once the 1-MCP did not solve the problems of yellowing of the leaves and floral openning, which are important characteristics for its commercialization.

El objetivo de este trabajo fue estudiar el efecto del dióxido de cloro a 3 y 5 mg L-1 (ClO2 3 y ClO2 5), peróxido de hidrógeno a 30 y 50 mg L-1 (H2O2 30 y H2O2 50) y radiación UV-C a 4 y 5 kJ m-2 (UV-C 4 y UV-C 5) sobre la tasa respiratoria, coloración y calidad microbiológica de hojas de rúcula (Eruca vesicaria), conservadas durante ocho días bajo atmósfera modificada pasiva a 5 ºC, y comparar su efecto con el hipoclorito de sodio a 100 mg L-1 (NaClO 100). Después de la cosecha, las hojas de rúcula fueron trasportadas del campo y almacenadas durante 24 h en una cámara a 5 ºC. Posteriormente se procesaron a 8 ºC, se lavaron por inmersión durante 3 min en agua potable, para luego ser sometidas a los diferentes tratamientos. La calidad microbiológica resultó claramente influenciada por los sanitizantes evaluados. Los tratamientos ClO2 5 y H2O2 50 redujeron los recuentos de enterobacterias en 1,3 log UFC g-1 con respecto a la materia prima, mientras el NaClO junto al ClO2 5 y H2O2 50 fueron los más efectivos en el control de bacterias aerobias mesófilas, reduciendo los recuentos entre 1,0 y 1,4 log UFC g-1. El ClO2 también fue efectivo en reducir la carga de microorganismos psicrófilos, a diferencia del NaClO. Todos los tratamientos conservaron el color de las hojas. Estos resultados sugieren que los sanitizantes ClO2 y H2O2 pueden ser utilizados como alternativa al NaClO en el lavado postcosecha de hojas de rúcula considerando la calidad microbiológica y la coloración verde durante la conservación refrigerada.

The aim of this work was to evaluate the effect of chlorine dioxide (3 and 5 mg L-1; ClO2 3 and ClO2 5), peroxide hydrogen (30 and 50 mg L-1; H2O2 30 and H2O2 50) and UV-C radiation (4 and 5 KJ m-2; UV 4 and UV 5) on the respiration rate, color and microbiological load of arugula leaves (Eruca vesicaria), stored eight days under a passive modified atmosphere at 5 °C; and to compare them with sodium hypoclorite 100 mg L-1; (NaClO 100). After the harvest, the leaves of arugula were transported from the field and stored for 24 h in a chamber at 5°C. The processing was carried out at 8 °C, where the leaves were washed by immersion for 3 min in potable water, before being subjected to different treatments. The microbiological quality was clearly influenced by the sanitizers evaluated. ClO2 5 and H2O2 50 decreased the enterobacteria counts in 1.3 log CFU g-1 compared to the raw material, while NaClO, ClO2 5 and H2O2 50 were the most effective delaying the aerobic mesophilic bacteria, decreasing the counting between 1.0 and 1.4 log CFU g-1. Unlike NaClO, ClO2 also reduced the load of psychrophile microcoorganisms. All treatments preserved the color of the leaves. These results suggest that ClO2 and H2O2 can be used as an alternative to NaClO in the postharvest washing of arugula leaves considering microbiological quality and green color during refrigerated storage.