Top PDF Conservation of crisp lettuce in different post-harvest storage conditions

Conservation of crisp lettuce in different post-harvest storage conditions

Conservation of crisp lettuce in different post-harvest storage conditions

The initial symptoms of excessive water loss are leaf wilting and wrinkling, which may accelerate deterioration due to increased catabolic source reactions (Finger & Vieira, 1997). In contrast, the leaves stored in closed plastic packaging without and with refrigeration presented low loss of fresh mass, about 7.5% and 3.5%, respectively. These results demonstrate the importance of using packaging in storage. According to Chitarra & Chitarra (2005), the packages allow the selective exchange of gases from the interior with the external atmosphere, causing the elevation of carbon dioxide level and decrease of oxygen, with the aid of product respiration. However, refrigeration slows the maturation, respiratory activity and decreases the heat production of the samples, showing efficiency in relation to the loss of fresh leaf mass and prolonging the commercial life of these products (Chitarra & Chitarra, 1990).
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Effect of Different N Fertilization Times on Post-Harvest Quality of Spinach (Spinacea oleracea L.)

Effect of Different N Fertilization Times on Post-Harvest Quality of Spinach (Spinacea oleracea L.)

Leaf discoloration is attributed to degradation of the leaf pigments or tissue browning. These physiological processes occur when cell membranes lose their integrity and release enzymes, which come into contact with their substrates, generating postharvest disorders (Jacxsens et al., 2002). Internal qualities such as antioxidant components are also important for human health because of their nutritional value. Chlorophyll and carotenoids are tightly correlated with each other because the latter protects the chlorophyll from photo-oxidation during growth (Biswall, 1995). This phenomenon has been observed in many leafy vegetables. It is known that the chlorophyll content of leafy plants such as chicory, Swiss chard and valeriana lettuce (Ferrante and Maggiore, 2007) decreases during storage.
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Post-harvest conservation of Passiflora alata fruits under ambient and refrigerated condition

Post-harvest conservation of Passiflora alata fruits under ambient and refrigerated condition

Texture influences post-harvest fruit handling, because it is directly related to firmness, resistance and integrity of the fruit tissues (Cenci, 2006). Firmness is reduced during maturation, which is attributed to changes in the pectin molecules (Canteri et al., 2012), catalyzed by the enzymes pectinmethylesterase and polygalacturonase (Pinheiro, 2008). On the present work, the fruit kept under ambient conditions had a significant reduction in texture after seven days of storage, and the 10 μm PVC treatment was the only one lacking significant loss between the seventh and fourteenth day of storage (Table 2). Also, the 10 μm PVC treatment was the only one in refrigerated storage that maintained statistically uniform texture values in the first seven days (Table 2). Although, the refrigerated environment was not effective in maintaining fruit resistance after 14 days of storage, since there was a statistically significant reduction of texture in all treatments (Table 2). This result agrees with Silva et al. (1999), who also showed significant texture loss in the refrigerated storage of P. alata fruits.
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Effect of the addition of calcium chloride and different storage temperatures on the post-harvest of jabuticaba variety Pingo de Mel

Effect of the addition of calcium chloride and different storage temperatures on the post-harvest of jabuticaba variety Pingo de Mel

The objective of this study was to analyze the effect of different calcium chloride concentrations on the post-harvest conservation of jabuticaba variety Pingo de Mel at different storage temperatures. The fruit were collected 30 days after the anthesis and subjected to immersions in calcium chloride solution at different concentrations (0%, 2%, 4%, and 6%) for 30 minutes at room temperature. Then, the fruit were dried and packed in polypropylene bags and incubated in a chamber at different temperatures (6 °C, 12 °C, and 25 °C). Samples were analyzed at time 0 and every two days, up to 12 days of storage. No effect of different calcium chloride concentrations was observed in the fruit characteristics at different storage temperatures over time. During storage, an increase of soluble and total pectin contents, antioxidant activity, CD 2 , total sugars, acidity, and weight loss was observed. Higher storage temperatures affected both the increase in weight loss, pH, and D 2 production and the reduction of vitamin C content. Refrigeration was important for the post-harvest conservation of jabuticaba variety Pingo de Mel, once the fruit stored at 6 °C suffered minor variations with improvements or little changes during the 12 days.
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Post-harvest conservation of camu–camu fruits (Myrciaria dubia (Kunth) Mc Vaugh) using different temperatures and packages

Post-harvest conservation of camu–camu fruits (Myrciaria dubia (Kunth) Mc Vaugh) using different temperatures and packages

The fruits stored under different temperatures also presented linear and growing response when the variable fresh mass loss without nay difference between those stored at 25 ± 2 °C and at 20 °C, in which at the end of the experimental period, the fruits already were wilt and with loss of turgescence, brightness and coloration. But, in the fruits stored at 15 °C this loss was significantly smaller where the same ones kept a better appearance for a longer period. The fruits stored at the temperature of 25 ± 2 °C from the tenth day’s storage were no longer suitable for consumption and with signals of fermentation and because of this reason they were not evaluated (Figure 1). That is, both the use of packing as the most significant effect at low temperatures and better preserved fruits during storage days.
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Utilização de ácido cítrico para a conservação pós-colheita de raízes de mandioca The use of citric acid in the post-harvest conservation of cassava roots

Utilização de ácido cítrico para a conservação pós-colheita de raízes de mandioca The use of citric acid in the post-harvest conservation of cassava roots

Minimally processed table cassava roots have emerged as an alternative to increase the post-harvest life of the product, and make a more practical, safer food available for consumers. The Brazilian Federal District and surroundings are becoming a major cassava producer and consumer. Thus the objective of this study was to determine the effects of different concentrations of citric acid (0.5%, 1.0%, 1.5%, 2.0%, 2.5%) in the conservation of minimally processed IAC 576-70 cassava roots immersed in water. The product was maintained at a temperature of 3 °C for 35 days. The following analyses were carried out on the raw material and on the product during storage: pH, titratable acidity, soluble solids, ratio, cooking time, colour and texture of the roots. The action of the citric acid on the shelf life of the product was positive for all concentrations throughout storage. There were significant reductions in pH and increases in titratable acidity of the product for all the citric acid concentrations evaluated, being less pronounced in the product subjected to a concentration of 0.5%. Visually the presence of microorganisms was not observed in any of the minimally processed cassava roots or in the water in which they were submerged.
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Alternative control of post-harvest diseases in Tainung 1 papaya

Alternative control of post-harvest diseases in Tainung 1 papaya

The pathogens used in the in vitro experiment were Alternaria sp., Colletotrichum gloeosporioides, Fusarium sp., Lasiodiplodia theobromae and Rhizopus sp., which were isolated from papaya fruits (Tainung 1 cultivar). The isolates were identified based on visual morphological characteristics in an optical microscope, using a dichotomic key (Barnett & Hunter 1998). The clove essential oil used was obtained by hydrodistillation. The products used to control the pathogens were a biological fungicide based on Trichoderma harzianum conidia (Trichodermil ® , 48 g L -1 ), a resistance inducer based
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Stevia rebaudiana Bertoni cultivated in Portugal: A prospective study of its antioxidant potential in different conservation conditions

Stevia rebaudiana Bertoni cultivated in Portugal: A prospective study of its antioxidant potential in different conservation conditions

Studies with well-established cultivation conditions are of utmost importance in order to standardize the plants production and, therefore, its chemical composition. However, the conservation conditions may influence some of the bioactive compounds present in those plants. Stevia rebaudiana Bertoni samples cultivated in the north-eastern of Portugal, were exposed to different conservation conditions (oven-dried at 30 °C, for six days, or kept fresh by freezing (-20 °C) in the same period), and then studied for their antioxidant potential (including antioxidant compounds such as reducing sugars, tocopherols and phenolic compounds, free radical scavenging activity (DPPH) and reducing power (RP)). Oven-dried samples gave the highest antioxidant activity (DPPH EC 50 = 22.87 µg/mL and RP EC 50 = 28.79 µg/mL) and the highest total phenolic
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Eletrical conductivity and deterioration of soybean seeds exposed to different storage conditions

Eletrical conductivity and deterioration of soybean seeds exposed to different storage conditions

Thus, reviewing the deterioration process of seeds, McDonald (1999) reported that lipid peroxidation has frequently been pointed to as the main cause of deterioration and considering that lipids are part of the cell membrane of seeds, there would be a direct relation between lipid peroxidation and the loss of the cell membrane integrity. On the other hand, alterations in carbohydrates during storage could affect the cell membrane permeability, thus contributing to the reduction in the physiological quality and germination of seeds (Crowe et al., 1984; Bernal-Lugo and Leopold, 1992). The damage caused to membrane through deterioration that provides lower selectivity and hence increase in the leakage of solutes to the environment has been one of the main causes of the decline in the physiological quality of seeds. As result, the electrical conductivity test is considered as an important tool to evaluate the seed vigour, since it indirectly assesses the cell membrane degradation degree by determining the amount of electrolytes released in the seed soaking solution. The electrical conductivity results may be affected by several factors. Tao (1978) evaluated the use of this test for soybean seeds and reported the influence of seed size, water quality, initial seed water content, volume of water used and the presence of physically damaged seeds. Loeffler et al. (1988) verified the effect of these factors; however the authors stressed that the variables indicated could be controlled by standardizing procedures in order to provide a non-subjective evaluation of the physiological quality of soybean seeds. Later researchers (Hampton et al., 1992; Vieira et al., 1996 and 2002) corroborated these results.
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Ozonated water in the post-harvest treatment of coffee fruits

Ozonated water in the post-harvest treatment of coffee fruits

After performing the coffee washing, fruit drying is considered one of the critical points in the quality of the final product. This is because some fungi species may associate with the grains and cause undesirable post-harvest changes (Ferreira et al., 2011). According to Silva et al. (2013) and Iamanaka (2014), the most common fungi that cause deterioration of the grains are Aspergillus species, Cladosporium spp. (at least two species), Fusarium spp. (at least six species), Phomaherbarium and the Penicillium genus.

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Multi-trait analysis of post-harvest storage in rocket salad (Diplotaxis tenuifolia) links sensorial, volatile and nutritional data

Multi-trait analysis of post-harvest storage in rocket salad (Diplotaxis tenuifolia) links sensorial, volatile and nutritional data

Rocket salad (Diplotaxis tenuifolia; wild rocket) is an important component of ready to eat salads provid- ing a distinct peppery flavour and containing nutritionally relevant compounds. Quality deteriorates dur- ing post-harvest, in relation to time and storage temperature amongst other factors. Volatile organic compounds (VOCs) are easily measurable from rocket leaves and may provide useful quality indicators for e.g. changes in isothiocyanates derived from nutritionally important glucosinolates. VOC profiles dis- criminated storage temperatures (0, 5 and 10 °C) and times (over 14 days). More specifically, concentra- tions of aldehydes and isothiocyanates decreased with time paralleling a fall in vitamin C and a reduction in sensorial quality at the two higher temperatures. Sulphur containing compounds rise at later time- points and at higher temperatures coincident with an increase in microbial titre, mirroring a further drop in sensorial quality thus indicating their contribution to off-odours.
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Quality of eggs sold in different commercial establishments and the study of the conditions of storage

Quality of eggs sold in different commercial establishments and the study of the conditions of storage

The weight loss of the eggs increases linearly with increased storage time. However, these losses are greater when the eggs are stored without control of humidity and temperature. Barbosa  et  al. (2008) demonstrated that eggs subjected to a controlled environment had an average loss of 3.63% of the initial weight, while the eggs stored in an uncontrolled environment had an average loss of 9.20%. However, Keener  et  al. (2006) found that the egg average weight of 62 g was kept without any influence of storage time, and there was no significant difference between the weight of the eggs and the temperatures analyzed. As for the albumen height, a significant difference was obtained in the eggs that were stored at room temperature from day 0 to 21 days and the storage temperatures of 7, 14, and 21 days, which proves that the internal quality of the egg decreases with time and that the cooling temperature also influences egg internal quality. Furthermore, the results were lower than those found in the literature. This can be justified by the time between laying and delivery to the distributor, which was of 6 days, since the aviaries were located far from the aviaries establishments evaluated.
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Postharvest conservation of fresh and minimally processed ‘Dekopon’ tangerine in different temperatures and storage times

Postharvest conservation of fresh and minimally processed ‘Dekopon’ tangerine in different temperatures and storage times

‘Tarocco Meli’, ‘Moro’, ‘Ovale’ and ‘Valencia’) stored at 6±1 °C for 65 days (0, 20, 40 and 65). An increase in TSS during storage occurred in all samples. The TSS and TA ratio increased during storage in all varieties with the exception of ‘Valencia’ orange where a drop was observed on the 65th day of storage. Fruit weight loss after 65 days of storage was less than 5% with respect to initial weight. Titratable acidity remained constant in the early stages of storage, and then decreased in all the varieties, except for ‘Valencia’ orange which increased slightly. This trend is reflected on pH levels which significantly increased at the end of storage, whereas a slight decrease in ‘Valencia’ fruit was observed. Citric acid has been reported to decrease in stored citrus fruit and this decline may be in part due to use of organic acids for energy production and alcoholic fermentation. These results are not in agreement with our study, because the TA increased or did not a significative difference for fresh and minimally processed tangerines, respectively, in the course of storage time.
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HEALTH AND PHYSIOLOGICAL POTENTIAL OF SOYBEAN SEEDS SUBMITTED TO DIFFERENT STORAGE CONDITIONS

HEALTH AND PHYSIOLOGICAL POTENTIAL OF SOYBEAN SEEDS SUBMITTED TO DIFFERENT STORAGE CONDITIONS

In soybean, the field fungi include the genera Colletotrichum, Phomopsis, Cercospora and Fusarium, among others (RATHOD & PAWAR, 2012; WAIN- TASSI et al., 2012). The association of these fungi with seeds occurs while these are still in the field, before harvest, and they can cause damage after sowing. These fungi do not affect seed physiological quality during storage because they only develop when seed moisture content is higher than 20% and relative humidity higher than 95% (DHINGRA, 1985; MARCOS FILHO, 2005). A reduction in seed moisture content halts development of the field fungi, and these may remain dormant or gradually die (DHINGRA, 1985).
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The use of neem oil and chitosan during pre-harvest and in the post-harvest quality of the ‘Paluma’ guava

The use of neem oil and chitosan during pre-harvest and in the post-harvest quality of the ‘Paluma’ guava

The district of Mamanguape, Paraíba, is located in the North-Coastal mesoregion, at 6°35’05” S and 35°23’50” W. The local climate is tropical rainy, with dry summers and a rainy season from February to October; the average rainfall is 1,634.2 mm (SOUZA; SOUZA, 2010). Eighteen guava trees were randomly selected and identified, with each treatment consisting of two plants. The orchard was selected immediately after the plants were pruned, and was free from herbicides to avoid any interference in the end results of the experiment. Throughout the experimental period, cropping treatments were carried out, including supplying water via micro- sprinkler irrigation, the elimination of spontaneous plants and the application of fertiliser.
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Post-harvest evaluation of tomato genotypes with dual purpose

Post-harvest evaluation of tomato genotypes with dual purpose

The firmness is desirable at the mechanized harvest, implying in less damage to the fruits in this operation. That characteristic grants resistance against mechanical damages during transportation, which for industrial fruit is usually done in bulk. The fruits of soft consistency usually are deformed during transport, occurring disruption of the skin and release the cell juice, causing fermentation, deterioration and loss of industrial output (Soares & Rangel, 2012). The tomato whit firm skin, are resistant to handling and have better capacity of conservation when compared to thin or soft skin (Chitarra & Chitarra, 2005).
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Evaluation of Sperm Kinetics and Plasma Membrane Integrity of Frozen Equine Semen in Different Storage Volumes and Freezing Conditions

Evaluation of Sperm Kinetics and Plasma Membrane Integrity of Frozen Equine Semen in Different Storage Volumes and Freezing Conditions

program R of descriptive analysis box plot, followed by analysis of variance using PROC MIXED of SAS 9.1 package. Variances of 5% were considered as different. There was no interaction between the straw sizes and volumes; however, statistical differences were observed between the semen storage volumes. The 0.5-mL straws had higher total motility (%), progressive motility (%), average path velocity ( m m/s), straight-line velocity ( m m/s), curvilinear velocity ( m m/s), and rapid sperm percentage (%) than the 0.25-mL straws. However, plasma membrane integrity analysis did not differ between the two straws. Thus, it is possible to conclude that equine sperm cryopreserved in 0.5-mL straws has better sperm kinetics than when stored in 0.25-mL straws. Additionally, it is possible to conclude that automated systems that enable faster freezing rates result in a seminal quality that is similar to the one obtained by the conventional system using Styrofoam boxes.
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Neutrosophic Crisp Points & Neutrosophic Crisp Ideals

Neutrosophic Crisp Points & Neutrosophic Crisp Ideals

Neutrosophy has laid the foundation for a whole family of new mathematical theories, generalizing both their crisp and fuzzy counterparts. The idea of "neutrosophic set" was first given by Smarandache [12, 13]. In 2012 neutrosophic operations have been investigated by Salama at el. [4 - 10]. The fuzzy set was introduced by Zadeh [13]. The intuitionstic fuzzy set was introduced by Atanassov [1, 2, 3]. Salama at el. [9] defined intuitionistic fuzzy ideal for a set and generalized the concept of fuzzy ideal concepts, first initiated by Sarker [11]. Here we shall present the crisp version of these concepts.
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Egg quality assessment at different storage conditions, seasons and laying hen strains

Egg quality assessment at different storage conditions, seasons and laying hen strains

Eggs are one of nearly perfect protein foods, offering nutrients of great biological value. However, during storage, egg albumen and yolk components may alter and deteriorate egg quality. Therefore, the aim of this work was to assess egg quality during 9-week storage. Parameters such as Haugh unit, weight loss, egg width and length, specific gravity, yolk and albumen dimensions and their pH were evaluated weekly. A total of 270 eggs (n=5) collected from two different hen strains were evaluated under room (20 to 35 °C in summer; 11.2 to 29.7 °C in autumn) and refrigerated (0 to 5 °C in summer; -3.1 to 6.5 °C in autumn) temperatures. For storage time, an unfolding analysis was accomplished by regression analysis using orthogonal polynomials. As a second approach, principal component analysis (PCA) was performed in order to assess correlations among quality parameters on storage conditions and laying hen strains. By the end of the 9-week storage period, eggs kept under refrigeration presented similar quality parameters to eggs stored at room temperature for only 3 weeks. In contrast, eggs kept at room temperature presented faster degradation from week 1 to 5. No differences on egg quality parameters were noticed between white and brown shells eggs. PCA suggests that better egg quality (first week) was associated mainly with higher egg weight and its specific gravity, Haugh unit and albumen height. Eggs stored at room temperature should be consumed in 2 weeks or refrigerated until 8 weeks, preserving internal quality from farm to retail.
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Resistance in Capsicum spp. to anthracnose affected by different stages of fruit development during pre- and post- harvest

Resistance in Capsicum spp. to anthracnose affected by different stages of fruit development during pre- and post- harvest

This study aimed to investigate the reaction of unripe and ripe fruits of Capsicum spp. accessions to Colletotrichum gloeosporioides during the pre- and post-harvest periods, and to identify sources of resistance for use in plant breeding programs. Thirty-seven Capsicum spp. accessions of the Universidade Estadual do Norte Fluminense Darcy Ribeiro were evaluated. They were cultivated in a greenhouse and arranged in a completely randomized design with five replications. Twenty fruits from each accession were inoculated at two stages (unripe and ripe) in two different environments (fruits inoculated in the plant and detached fruit inoculated under laboratory conditions). The symptoms were assessed every 24 hours between the 1st and 8th days after inoculation. There were highly significant differences in the values of the area under the disease progress curve and in severity, considering all sources of individual variation and their interactions. Values of low and moderate correlation were observed for inoculation of unripe and ripe fruit in both environments. These results indicate the existence of distinct genes responsible for resistance at different stages of fruit development. Complete lack of symptoms was registered only for accessions UENF 1718 and UENF 1797 (C. baccatum var. pendulum).
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