ABSTRACT The curing before storing the tubers is necessary for the formation of damage periderm, promoting greater post-harvest conservation. In which, the rate curing and the maintenance of the quality of the tubers depends on the temperature. This way, the search aimed to determine the effect of the curing temperature on the regeneration of the damage periderm and on the carbohydrate metabolism of cultivar Markies and Challenger potatoes tubers destined for industry. For this, the curing was carried out for 14 days on tubers with excoriation injury and tubers without excoriation (control) at temperatures of 8, 14 and 20 °C (RH ± 90%). The fresh mass loss rate (FMLR) daily was higher in the excoriation tubers. The excoriation injury and the temperature of 8 °C increased the total soluble sugar (TSS), reducing sugars (RS) and non-reducing sugars (NRS) of the tubers of ‘Markies’ and TSS of ‘Challenger’. The excoriation injury tuber the process of cell division was induced in the periclinal plane, forming phellogen, with few layers of collapsed cortical cells. In both cultivars, at 14 °C the new phellogen became more evident and at 20 °C some layers of a new cork were formed. In ‘Markies’ the development of new periderm was earlier than in ‘Challenger’, even at 8 °C. It is concluded that the temperature of 14 ºC provided better curing and regeneration of the excoriation periderm tubers maintain post-fry quality of potatoes destination by industry processing.

RESUMO: Objetivou-se com este estudo verificar a eficiência do 1,4-dimetilnaftaleno na supressão da brotação e a consequente manutenção da qualidade de tubérculos de batata das cultivares Asterix e Challenger, em diferentes temperaturas e tempos de armazenamento. Foram testados seis tratamentos, com e sem 1,4-DNM, nas temperaturas de 8 °C e 20 °C. As avaliações foram feitas aos 0, 45, 90, 135 e 180 dias após a aplicação. Os parâmetros avaliados foram: número de brotos, teores de açúcares solúveis totais, teores de açúcares redutores, e não redutores, e coloração dos palitos de batata após a fritura. Os efeitos do 1,4-DMN no controle da qualidade das batatas resultaram no controle da brotação e em menores teores de açúcares solúveis totais e de açúcares redutores, sobretudo na cultivar Challenger e à temperatura de 20 ºC.

ABSTRACT: The aim of this study was to verify the efficiency of 1,4-dimethylnapthalene in suppressing sprouting and the consequent maintenance of the quality of potato tubers of Asterix and Challenger cultivars, at different temperatures and storage regimes. Six treatments were tested, with and without 1.4-DNM, at temperatures of 8 ° C and 20 ° C. Assessments were made at 0, 45, 90, 135 and 180 days after application. The parameters evaluated were: number of sprouts, levels of total soluble sugars, levels of reducing and non-reducing sugars and coloration of potato strips after frying. The effects of 1.4-DMN on the quality control of potatoes resulted in sprout control and lower levels of total soluble sugars and reducing sugars, especially in the Challenger cultivar and at a temperature of 20 ºC.

Abstract Changes in the population's eating habits have expanded the French fries market. However, the need for refrigerated storage to supply sprouts and maintain a constant supply to the industry has led to a reduced number of cultivars suitable for processing due to the accumulation of sugars and browning after frying. Because of this, the objective of this study was to evaluate the suitability of the Donata and BRS F132 cultivars for use in the pre-fried potato processing industry. The tubers were stored at 6 and 8 °C for up to 180 days and the analysis of sprouting, total soluble sugar (TSS), reducing sugar (RS), non-reducing sugar (NRS), post-frying color by scale visual color used by the industry and L* and b* parameters. The sprouting was higher at 8 °C and in the BRS F 132 cultivar. The sugar content was high in both cultivars, however, the color remained adequate. It is concluded that the Donata and BRS F132 cultivars are suitable for the potato processing industry, and Donata presented better quality parameters. Conditioning at 8 °C is recommended in both cultivars that maintained the quality for 180 days.

Abstract This work aimed to analyze 1,4-DMN efficiency in the suppression of sprouting and the consequent maintenance of quality in potato tubers of Asterix and Challenger cultivars stored during different periods under varying temperatures: eight treatments with and without 1,4-DMN under temperatures of 8 °C and 20 °C. Treatments effect were evaluated after 0, 45, 90, 135 and 180 days after application. The evaluated parameters were the loss of fresh mass, length of the sprouts and activity of the enzymes polyphenoloxidase and peroxidase. The results indicate that the application of 1,4-DMN reduces the loss of fresh mass, this effect was more intense for the cultivar Challenger, at 8 °C. There were also significant effects in reducing the average length of the sprouts for both cultivars evaluated, after 180 days, at 20 °C. There was little or no difference in the level of oxidative stress caused in the tubers. Hence, the effects of 1,4-DMN on the quality control of potatoes included reduced loss of fresh mass and a shorter average length of sprouts for both cultivars evaluated compared to control, for both temperatures. These effects intensify in the cultivar Challenger and treatments with temperatures of 20 °C.

ABSTRACT. Excoriation damage is among the major causes of postharvest potato losses. Curing is known to increase the resistance of tubers to excoriation injury, with the temperature influencing the traumatic phellogen and periderm regeneration, as well as tuber processing quality. This study aimed to evaluate the effects of excoriation procedure and curing temperature on the industrial quality, histological characteristics, carbohydrate metabolism, and oxidative enzyme activity of potato tuber. Tubers with or without excoriation were cured at 8, 14, and 20°C for 15 days. Excoriation did not influence the levels of reducing sugars (RS), as well as polyphenoloxidase (PPO) and peroxidase (POD) activities. The concentrations of total soluble sugars (TSS) and non-reducing sugars (NRS) were higher in injured tubers, while reduction in curing temperature increased the concentrations of TSS, NRS, and RS. However, the sugar content was adequate as per the criteria of the pre-fried potato industry and potatoes classified in category 2 (USDA/fast-food industry color grading). The reduction in curing temperature also increased the activity of POD, despite the activity of PPO remaining unchanged. Formation of a closure layer from the outer parenchyma cells of the tuber that prevents desiccation and death of superficial cells, was observed. This protection was completed with the formation of the damage periderm. Periderm regeneration is faster at higher temperatures, 15 and 20°C, leading to a lower fresh mass loss and no enzymatic or non-enzymatic browning. The excoriation carried out at 14/20oC for 15 days was sufficient for curing, and for maintaining suitable post-fry quality of potatoes.

ABSTRACT The MeJA has been shown to be promising in reducing the damages caused by cold and maintaining the quality in several products. Nevertheless, few studies are conducted with flowers and there are no studies of its use in bird of paradise. The objective of this study was to determine whether the pulsing application with MeJA submitted to cold storage promotes physiological changes of the bird of paradise. Flowers were placed in solutions of 200 g L-1 sucrose added with 100, 250 and 400 μmol L-1 MeJA and control without MeJA, for 24 h. The stems were transferred to containers with water at 5 ºC for 28 days. During storage, the water absorption, transpiration and fresh mass were reduced, while the extravasation of electrolytes and phenolic compounds increased. The application of MeJA did not reduce the loss of fresh mass and extravasation of electrolytes. The application of 400 μmol L-1 MeJA has increased peroxidase activity since day 14 of storage. It is concluded that the application of MeJA with pulsing under refrigeration does not promote positive physiological changes for the maintenance of the quality in bird of paradise flowers.

ABSTRACT The refrigerated induce the sweetening of the potato, which results in the dark color. The objective of this study was to determine the temperature and shelf life of Markies potato tubers under refrigerated storage for the processing of French fries. The levels of total soluble sugar (TSS), reducing sugars (RS), peroxidase (POD) and polyphenoloxidase (PPO) activity, color after frying and start of sprout were determined. The accumulation of TSS started at 30 days in the tubers at 4 and 5 °C and in the tubers at 6 and 8 °C, at 150 days. The activity of POD and PPO were not influenced by temperature or storage time. Tubers at 4 e 5 °C showed higher TSS and RS contents and darker color after frying than tubers stored at 6 and 8 °C which had their color maintained within the industry-acceptable standard up to 240 days of storage. Temperatures of 4 and 5 °C delayed the onset of sprouting, starting at 150 days, and at temperatures of 6 and 8 °C, the onset of sprouting occurred from 90 and 60 days of storage, respectively. It is concluded that the cultivar Markies should be stored at 6 °C for 240 days.

Abstract The objective of this study was to determine the storage efficiency and reconditioning of potato cv. Innovator for processing. Tubers were stored at 6, 7 and 8 °C in the dark for 30, 60, 90, 120 and 150 days and reconditioned at 15 °C for 15 days. TRS and RS were reduced as storage temperature increased from 6 + 15 °C to 8 + 15 °C. Regardless of temperature and storage time, sugar contents were suitable for industry; however non-enzymatic browning remained in category 2 for up to 60, 90 and 150 days in tubers stored at 6 + 15 °C, 7 + 15 °C and 8 + 15 °C, respectively. Starch was influenced by storage time, despite the absence of temperature effect. Regardless of the temperature, sprouting started at 90 days, but the growth of shoots was directly proportional to the increase in temperature. The PPO and POD increased at the beginning of storage but did not cause darkening before the frying. Reduction in storage temperature followed by reconditioning did not delay the onset of sprouting, but reduced the size of sprouts, maintained adequate sugar levels, however it promoted non-enzymatic browning.

RESUMO: As batatas destinadas ao processamento industrial devem ter alto teor de matéria seca, baixo teor de açúcar e estar livre de danos ou doenças. O objetivo foi determinar a temperatura e o período de armazenamento ideais para cultivares comerciais para fritura. Os tubérculos das cultivares Asterix e Cronos foram armazenados em caixas de plástico a 6 e 8 °C com umidade de 85 a 95% por 180 dias. As perdas de massa acumulada (PMA), sólidos insolúveis em álcool (SIA), açúcares solúveis totais (AST), açúcares não redutores (ANR), açúcares redutores (AR), atividade de polifenoloxidase (PPO) e escurecimento enzimático e não enzimático foram analisadas. A PMA de tubérculos da cultivar Asterix a 6 e 8 ºC e a da cultivar Cronos, armazenadas a 6 °C foram maiores. Os teores de SIA foram menores e os de AST, AR e ANR maiores nos tubérculos de ambas as cultivares armazenadas a 6 ºC. A temperatura e o período de armazenamento não afetaram as cultivares Cronos e Asterix. O escurecimento foi maior nos palitos fritos das cultivares Asterix e Cronos armazenados a 6 ºC (4 a 5) por 60 e 90 dias e a 8 °C (2 a 3) por 180 dias, respectivamente. O período ideal de temperatura e armazenamento para as cultivares Asterix e Cronos é de 8 ºC por, no máximo, 120 dias devido ao escurecimento não enzimático.

ABSTRACT: Potatoes for industrial processing must have high dry matter, low sugar and free from damage or disease. The objective was to determine the ideal temperature and storage period of commercial cultivars for frying. Tubers of Asterix and Cronos cultivars were stored in a cold chamber (Gallant CMC4 Premium) inside plastic boxes at 6 and 8 °C with 85 to 95% humidity for 180 days. Accumulated mass loss (PMA), alcohol insoluble solids (SIA), total soluble sugars (AST), non-reducing sugars (ANR), reducing sugars (AR), polyphenoloxidase activity (PPO) and enzymatic and non-enzymatic browning were analyzed. The PMA of Asterix at 6 and 8 ºC and Cronos at 6 °C was higher. The SIA of both cultivars stored at 6 ºC were lower and AST, AR and ANR higher. Those parameters of Cronos and Asterix did not differ between temperature or storage period. The browning was greater in the fried sticks of Asterix and Cronos stored at 6 ºC (4 to 5) for 60 and 90 days and at 8 °C (2 to 3) for 180 days, respectively. The ideal temperature and storage period for Asterix and Cronos cultivars is 8 ºC for a maximum of 120 days due to non-enzymatic browning.

RESUMO: O milho-pipoca (Zea mays var. everta) tem um valor comercial mais elevado do que o milho comum e é um alimento popular entre os consumidores. Hoje, existe uma constante busca por cultivares com desempenho superior para os diversos caracteres de interesse, no caso da pipoca, produtividade e capacidade de expansão. O trabalho propõe caracterizar progênies de milho-pipoca com diferentes valores de capacidade de expansão quanto à composição química e micromorfologia. Foram estudados grãos do quinto ciclo (C5) de seleção recorrente intrapopulacional. As progênies foram selecionadas com base nos valores de capacidade de expansão de seus grãos. Os grãos foram quantificados para amilose e analisados quanto ao arranjo dos grânulos de amido e espessura do pericarpo por microscopia eletrônica de varredura. Progênies com baixa capacidade de expansão (0 e 7 mL g-1) apresentaram teor de amilose de 21,24 e 20,18% respectivamente; endosperma menos compacto, com grânulos de amido individualizados e intercalados com espaços vazios; e espessura do pericarpo medindo entre 40,94 e 38,99 µm, respectivamente. Por outro lado, progênies com alta capacidade de expansão (30 e 35 mL g-1) apresentaram teor de amilose de 23,92 e 26,10%, endosperma vítreo, sendo os grânulos de amido mais compactos e sem espaços vazios entre eles; e espessura do pericarpo medindo entre 107,66 e 107,84 µm. Progênies com altos valores de capacidade de expansão apresentam maior espessura de pericarpo, alta porcentagem de amilose e endosperma mais compactado, enquanto as com menores valores de expansão, apresentam menor espessura do pericarpo, menor porcentagem de amilose e grânulos de amido individualizados.

ABSTRACT: Popcorn (Zea mays var. everta) has a higher commercial value than common maize, in addition to being a popular food among consumers. Today, there is a constant search for cultivars with superior performance for several traits of interest in the case of popcorn, yield and popping expansion. On this basis, this project proposes to characterize progenies of popcorn with different values of expansion capacity regarding chemical composition and micromorphology. Kernels from the fifth cycle (C5) of intrapopulation recurrent selection were evaluated. The progenies were selected based on the popping expansion volume of their kernels. The kernels were quantified for amylose and analyzed for starch granule arrangement and pericarp thickness by scanning electron microscopy. Progenies with low popping expansion volume (0 and 7 mL g-1) showed amylose contents of 21.24 and 20.18%, respectively; a less compact endosperm, with individual starch granules interspaced with empty spaces; and pericarp thickness between 40.94 and 38.99 µm, respectively. By contrast, progenies with high popping expansion volume (30 and 35 mL g-1) showed amylose contents of 23.92 and 26.10%; a vitreous endosperm; more-compact starch granules without empty spaces in between; and pericarp thickness between 107.66 and 107.84 µm. Progenies with higher popping expansion volume exhibited a thicker pericarp, a high amylose percentage and a more-compact endosperm, whereas those with the lower expansion volumes showed a thinner pericarp, a lower amylose percentage and individual starch granules.

RESUMO: Normalmente, não é recomendado o condicionamento de hastes de gladíolo em água durante o armazenamento ou transporte. A hidratação das pétalas acelera a abertura das flores, mesmo em baixa temperatura, o que compromete a qualidade no momento da comercialização. No entanto, para essa espécie, ainda não foi estudado o efeito do armazenamento refrigerado prolongado a seco e nem o seu comportamento quando transferida para a água em temperatura ambiente. O presente estudo teve como objetivo avaliar a vida de vaso e a capacidade de reidratação de hastes florais de gladíolo após armazenamento a seco em baixa temperatura ( Gladiolus grandiflora Hort.). As hastes das cultivares Blue Frost, Gold Field, Traderhorn e Jester foram armazenadas a seco em temperatura de 5 ± 1 ºC e umidade relativa de 85% por 12, 24, 36 e 48 horas. As hastes controle permaneceram sempre em água deionizada. Após armazenamento, retornaram a água sob condição de temperatura ambiente (22 ± 1 ºC) e foram avaliadas quanto à vida de vaso (adotando o critério de descarte quando 50% das flores basais apresentaram perda de coloração e murcha), variação da massa de matéria fresca (%), taxa de absorção de água e taxa transpiratória, bem como o teor relativo de água das pétalas (%). Em condições de armazenamento a seco em baixa temperatura, por até 36 horas, a vida de vaso não foi afetada, embora tenha ocorrido reidratação incompleta das flores. A capacidade de reidratação da haste está relacionada com a abertura escalonada das flores ao longo da inflorescência.

ABSTRACT: Normally, it is not recommended the conditioning of gladiolus stems in water during storage or transport. Hydration of petals may accelerate flower opening, even at a low temperature, which compromises quality at marketing moment. However, for this species, neither the effect of prolonged dry cold storage nor its behavior when transferred to water at room temperature has been evaluated. The present study aimed to evaluate the vase life and the rehydration capacity of gladiolus flowers ( Gladiolus grandiflora Hort.) after dry storage at low temperature. Flower stems of cultivars Blue Frost, Gold Field, Traderhorn, and Jester were dry-stored at a temperature of 5 ± 1 ºC and relative humidity of 85% for 12, 24, 36, and 48h. Control stems remained always in deionized water. After storage, they were returned to the water at room temperature and evaluated for vase life (adopting the discard criterion when 50% of the basal flowers displayed loss of color and wilting), fresh weight change (%), water uptake rate and transpiration rate, as well as relative water content of the petals (%). In dry cold storage conditions, for up to 36h, the vase life was not affected although incomplete rehydration of the flowers. Rehydration capacity of the stem is linked to the staggered opening of flowers along the inflorescence.

RESUMO Após a colheita da cebola, realiza-se a cura cuja finalidade é proporcionar a perda da umidade das folhas e secagem das películas externas (casca) dos bulbos, alcançando coloração externa atrativa e redução da intensidade de podridões. Objetivou-se com este trabalho utilizar uma unidade de tratamento de ar (UTA), conhecida como bomba de calor, como método alternativo de secagem e avaliar o tempo de secagem e a preservação das características químicas e físicas dos bulbos de cebola após a cura. O experimento foi conduzido no delineamento inteiramente casualizado com dez repetições e três tratamentos que consistiram em: T1- (Testemunha) cura natural realizada em galpão. T2- (aeração com ar aquecido artificialmente pela queima de propano) e T3- (aeração com ar aquecido e desidratado artificialmente por meio da UTA). Avaliou-se o tempo de finalização da cura, teor relativo de água (TRA) da casca e películas internas, coloração da casca e polpa, acidez total titulável (ATT), sólidos solúveis totais (SST), índice visual de superação da dormência (IVD) e perda de massa fresca (PMF). Não houve diferença significativa (p < 0,05) para a ATT, SST, IVD, PMF e coloração da polpa entre os tratamentos estudados. Conclui-se que o T3 permitiu a cura dos bulbos de forma mais rápida (12 horas), proporcionando bulbos com casca mais seca e coloração amarelo intenso.

ABSTRACT After harvest, onion bulbs are submitted to curing, whose objective is to provide loss of moisture in leaves and drying of outer layers (peel) of bulbs, reaching attractive external coloration and reduction in the intensity of rottenness. The objective of this study was to use an air treatment unit (ATU) - known as heat pump - as an alternative drying method, and to evaluate drying time and preservation of the chemical and physical characteristics. The experiment was carried out in a complete random design with ten replicates and three treatments, which were the following: T1- (control) natural curing in shed; (2) T2- (aeration with air artificially heated by propane burning); and (3) T3- (aeration with artificially dehydrated and heated air using ATU). Curing completion time, relative water content (RWC) of the skin and inner layers, pulp color and skin coloring, total titratable acidity (TTA), total soluble solids (TSS), visual index of dormancy breaking (VID), and fresh weight loss (FWL) were evaluated in this study. No significant difference (p < 0.05) were found for TTA, TSS, VID, FWL, and pulp color among treatments. It can be concluded that T3 promoted a faster curing (12 hours) of bulbs, which provided bulbs with drier skin and intense yellow color.

ABSTRACT The gladiolus flower is classified as insensitive to ethylene. Thus, the signals that initiate senescence are poorly understood. This study evaluated the role of abscisic and gibberellic acids on postharvest senescence of 3 cultivars of cut gladiolus flowers (Gladiolus grandiflora Hort.). Stalks were harvested and placed in test tube containing 100 mL distilled water or an aqueous solution of abscisic acid (100 and 150 µM ABA), gibberellic acid (100 µM GA3), and fluridone (1 mM) for 24 h. Subsequently, flower stalks were placed in a test tube with distilled water, and the following variables were determined: stem longevity, fresh weight change, water uptake rate and transpiration rate during the vase life, as well as membrane stability index and lipid peroxidation in 5 stages of flower development. In another experiment, the florets were removed by cutting down the pedicel. After removal, florets were placed in a beaker containing 10 mL distilled water or the following solutions: 100 or 150 µM ABA; 100 µM GA3; 1 mM fluridone; and 100 µM ABA + 100 µM GA3, followed by immersion in distilled water after 24 h in each treatment. Fresh weight change and transpiration rate of florets were assessed every 24 h. Abscisic acid is involved in the induction of senescence-related events in gladiolus flowers, such as high loss of membrane stability and abnormal flower opening. GA3 regulates the action of ABA in the maintenance of cell membrane and opening of gladiolus flowers.

O objetivo deste trabalho foi avaliar a composição de carboidratos e carotenoides em rizomas mãe e filhos das variedades de mangarito (Xanthosoma riedelianum) pequeno e gigante. Amostras dos rizomas coletadas ao longo do ciclo cultural e após 90 dias de armazenamento foram avaliadas quanto aos teores de carboidratos e carotenoides totais. Os rizomas apresentaram aumento no teor de carboidratos, e o rizoma-mãe da variedade pequeno apresentou acréscimos lineares no teor de carotenoides, ao longo do cultivo. O armazenamento reduz os teores de carboidratos e de carotenoides totais em todos os rizomas.

The objective of this work was to evaluate the composition of carbohydrates and carotenoids in mother rhizomes and small cormels of the dwarf and giant mangarito (Xanthosoma riedelianum) varieties. Rhizome samples collected during the crop cycle and 90 days after storage were evaluated for carbohydrate and total carotenoid contents. Rhizomes showed an increase in the carbohydrate content, and the mother rhizome of the dwarf variety had linear increases in the carotenoid content, during cultivation. Storage reduces carbohydrate and total carotenoid contents in all rhizomes.