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 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.

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.

O estabelecimento de condições ideais e a rapidez para condução do teste de germinação de sementes de girassol é de suma importância nos programas de controle de qualidade das empresas que se dedicam a produção de sementes com alta tecnologia. Dentro deste contexto, objetivou-se com este trabalho verificar a possibilidade de redução do tempo de avaliação do teste de germinação de sementes de girassol em diferentes substratos e temperaturas. Foram utilizados seis lotes de sementes da cultivar Hélio 251 e seis lotes da cultivar Hélio 253. Além da germinação, foram efetuadas as determinações de primeira contagem de germinação e sanidade. As sementes foram mantidas em câmara de germinação regulada a 25, 30 e 20-30 ºC, para o substrato papel, e 25 e 30 ºC para o substrato areia. Para verificar a possibilidade de redução do tempo de avaliação do teste de germinação, as contagens do número de plântulas normais foram realizadas diariamente, até o 10° dia após semeadura. Concluiu-se que é possível a finalização do teste de germinação no sétimo dia após a semeadura em areia na temperatura de 25 °C.

Establishing ideal conditions and speed in carrying out the germination test for sunflower seeds is of utmost importance in quality control programs of companies dedicated to the production of high technology seeds. In this regard, the aim of this study was to verify the possibility of reducing the evaluation time of the germination test of sunflower seeds in different substrates and temperatures. Six seed lots of the cultivar Helio 251 and six lots of the cultivar Helio 253 were used. As well as germination, determinations were made of first count germination and seed health. The seeds were kept in a germination chamber at 25 ºC, 30 ºC, and 20-30 ºC for the paper substrate, and 25 ºC and 30 ºC for the sand substrate. To verify the possibility of reducing the evaluation time of the germination test, the number of normal seedlings were counted daily, up to the tenth day after sowing. It was concluded that it is possible to conclude the germination test on the seventh day after sowing in sand at the temperature of 25 °C.