Caracterização da senescência e uso de filme de amido na conservação pós-colheita de bastão-do-imperador

Abstract

On the chain of flower production, one of the main obstacles is the adequate postharvest management, to understand this process, in particular the physiological and biochemical aspects, that is essential for the establishment of strategies that allow greater quality and durability for cut's flowers. The ginger torch has an extravagant and showy inflorescence with bright colors and is suitable for use as a cut flower in floral arrangements, and can be used at different opening points. For most tropical species, there is little information about the influence of the opening stage of the bracts in the post-harvest period. The characterization of the cut's flowers is of great importance because each crop has its own characteristics and different signs of senescence, which must be analyzed to better establish the post-harvest quality parameters. Aiming to increase the durability of the cut's flowers, different post-harvest technologies are used, such as the use of cassava starch as a basis for the composition of coating films applied to the inflorescences, as it increases the storage period, reducing respiratory activity and delaying senescence. Thus, the objective was to characterize morphologically the inflorescences and bracts of the 'Red Torch' ginger in the three different harvest points and to present a scale of senescence of the stems. Evaluate the use of glycerol plasticizer and adjuvant mixed in the composition of cassava starch films used as coating in the inflorescences and evaluate these films in post-harvest conditioning and durability of inflorescence through biochemical parameters related to senescence. The inflorescences were evaluated for morphological parameters. After carrying out the evaluations of the characteristics of the inflorescences, they were photographed every day for the realization of the visual scale of senescence. Starch concentrations (Control; 2%; 4% and 6%) in the solution and starch concentrations added with plasticizers and adjuvants in the solution were tested. Stems were evaluated every three days for visual quality (grade), physiological and biochemical characteristics of macromolecules and antioxidant system. The ginger torch inflorescences showed hydrophobicity characteristics, high fluid movement inside the cells, red color dominance and presence of wax in the bracts of the different harvest points, closed and semi-open. There are differences in characteristics of size and weight that influence the postharvest durability of 'Red Torch' ginger, of which the open flowers showed less durability than the two preceding points, closed and semi-open. The maintenance of visual quality was higher in the stems with 6% of starch and in the films without additives because the addition of both compounds worsened the optical properties, which compromised the appearance of the coated products. The inflorescences coated with 6% starch maintained lower levels of hydrogen peroxide and lipid peroxidation and higher contents of the macromolecules of primary metabolism until the sixth day after application, delaying senescence and helping to maintain postharvest quality.