Superficial scald development in 'Granny Smith' and 'Nicoter' apples: The role of key volatile compounds when fruit are stored under dynamic controlled atmosphere.

A positive correlation of α-farnesene and its oxidation metabolites with superficial scald is commonly reported in apples stored in air or controlled atmosphere (CA) systems, where O2 levels are above the lower oxygen limit (LOL) tolerated by the fruit. Nevertheless, the LOL can be monitored by the dynamic controlled atmosphere (DCA) techniques and to provide different physiological responses. Therefore, this study aimed to evaluate key volatile metabolites from 'Granny Smith' and 'Nicoter' ('Kanzi®') apples stored under dynamic controlled atmosphere (DCA) monitored by respiratory quotient (RQ), i. e. at extremely low oxygen partial pressures (ELO) and correlate their emissions with the incidence of superficial scald (SS). The volatile compounds (VCs) were isolated by solid phase microextraction (HS-SPME) and analyzed by gas chromatography. For the first time, higher concentrations of α-farnesene and its oxidation metabolites (6-methyl-5-hepten-2-one, and 6-methyl-5-hepten-2-ol) were negatively correlated with SS in DCA-RQ. This is likely due to the higher levels of ethanol in fruit stored under this condition having an inhibitory effect on SS incidence even when α-farnesene, 6-methyl-5-hepten-2-one, and 6-methyl-5-hepten-2-ol accumulate. Additionally, SS is more correlated to internal ethylene concentration (IEC) than α-farnesene accumulation and their metabolites, even when fruit were stored under ELO, where ethylene action is reduced.

Higher CO2 during controlled atmosphere storage of unshelled 'Barton' pecans or carnauba wax coating: Effect on the quality after long-term storage at two temperatures.

Pecan nuts, a healthy food, have shown an increased demand for consumption. Therefore, there must be a certain level of care to avoid quality losses, which are primarily influenced by storage conditions and time. This study evaluates the effects of long-term controlled atmosphere (CA) storage with low O2 partial pressure (pO2 - 2 kPa), combined or not with high CO2 (pCO2 - 40 or 80 kPa), carnauba wax coating (CW), and ambient atmosphere (AMB; control) at 10 and 20 °C, on unshelled 'Barton' pecan nut quality. Color, water activity (Aw), moisture content (MC), and oxidation markers, such as peroxide value (PV), acidity value (AV), TBARS, and volatile compounds (VC) were evaluated. Storage up to twelve months at 10 °C and with CA (regardless of the temperature) ensured higher luminosity and color parameter b* ("golden") and a lower a* parameter ("reddish"). The MC ranged from 2.8 to 3.6%, irrespective of storage conditions, for up to twelve months, which is suitable. The AMB at 10 °C ensured lower AV, TBARS, and PV compared to the CW treatment. Furthermore, CA with low pO2 and high pCO2, even at 20 °C, guaranteed lower AV, TBARS, and PV. Storage at 20 °C increased characteristic VCs of lipid oxidation (aldehydes, acids, alcohols, ketones, lactones, and esters, especially with CW coating). However, all conditions at 10 °C and with pCO2 (even associated at 20 °C) reduced the presence of these VCs. The CW used as a coating on the pecans did not show satisfactory results and should not be recommended for pecan storage at these applied conditions. Our findings showed that low pO2 and high pCO2 maintain better pecan quality than O2 ambient (20 kPa), even at temperatures above refrigeration (20 °C). Nevertheless, there were no significant differences between 40 and 80 kPa CO2.

Effects of controlled atmosphere and storage temperature on the quality of shelled 'Barton' pecan nuts during long-term storage.

This study aimed to evaluate the effects of controlled atmosphere (CA) storage at a low oxygen partial pressure (pO2; 2 kPa of O2) and low pO2 associated with high pCO2 (2 kPa O2 + 15 kPa CO2) in relation to ambient atmospheric conditions (control), at different temperatures, on shelled 'Barton' pecan nuts quality after storage. Color, respiration rates, moisture content (MC), and oxidation markers, such as peroxide value (PV), acidity value (AV), and volatile compounds (VC), were evaluated. During six months of storage, the MC decreased in all CA treatments, and treatments at 10 °C had the lowest AVs and PVs. However, the treatment with high pCO2 levels also guaranteed lower AVs at 20 °C. The color parameter b* (yellow), which is related to the golden appearance of pecans and is a highly desirable visual attribute in the commercialization of nuts, was maintained high in treatments at 10 °C with CA treatments until six months of storage. The VCs, characteristic of lipid oxidation (aldehydes, acids, alcohols, and ketones), increase in all treatments with prolonging storage. When pCO2 was associated to 10 °C at six month of storage, it showed a larger area in the acids and unsaturated aldehyde classes, while it was relevant for alcohols, lactones, and esters at 20 °C, with sweet characteristics, including ethyl ethanoate, ethyl hexanoate, and butyrolactone. Thus, this study shows another advance in the storage techniques of shelled pecans, pointing to alternatives for reducing energy costs in the cooling chain.

The effects of soybean storage under controlled atmosphere at different temperatures on lipid oxidation and volatile compounds profile.

This study aimed to evaluate the effects of low oxygen partial pressure (pO2) and high carbon dioxide partial pressure (pCO2) combined with different temperatures on the oil acidity and peroxide values of two soybean cultivars (NA 5909 RG and FEPAGRO 37 RR). The volatile compounds correlated to lipid oxidation were also evaluated. Soybeans were stored for seven months under ambient and controlled atmosphere (CA) conditions at three temperatures (20, 25, and 30 °C). Storage under ambient conditions increased acidity and peroxide value regardless of the temperature. CA storage with low pO2 reduced oil acidity and its combination with high pCO2 had no positive effects on oil acidity and peroxide values. Grains of FEPAGRO 37 RR stored under ambient air showed higher 1-octne-3-ol amount compared to CA. The higher storage temperature increased (E)-2-heptenal and decanal amount in grains of cultivar NA 5909 RG. In addition, the ambiente air storage provide higher γ-Butyrolactone in relation to CA storage. Moreover, in both cultivars the CA storage technique provides lower (E)-2-hexenal content. This compound, together with hexanal are potential lipid deterioration markers of soybeans. CA storage is a promising tool for soybean grains preservation and the effect is mainly due to the oxygen reduction, with no additional effect of CO2 increasing.

Chemical composition and oxidative stability of eleven pecan cultivars produced in southern Brazil.

Nuts are considered highly nutritious foods and a source of health-promoting compounds. Therefore, the aim of this study was to evaluate the chemical composition (proximate composition, fatty acids, volatile compounds, total phenolics, squalene, and ß-sitosterol) of eleven pecan cultivars harvested in Rio Grande do Sul State (Brazil) and investigate their oxidative stability by the Rancimat method. 'Barton' is the main cultivar produced in Brazil and presented the highest protein, linoleic acid, and linolenic acid values and the lowest saturated fatty acid values, which provide health benefits. 'Mahan' showed the highest oxidation induction time, both in extracted oil and ground samples, low abundance of lipid oxidation compounds, low polyunsaturated fatty acids, high levels of oleic acid and ß-sitosterol, which suggests potential for storage. 'Stuart' and 'Success' had the highest total dietary fiber values. Moreover, analysis showed that 'Chickasaw' and 'Success' had large quantities of compounds correlated to lipid oxidation, suggesting low stability for long-term storage. These results imply that the physicochemical characteristics and proximate composition of pecan nut cultivars from southern Brazil have variable parameters that may depend on their genetic variability.

Influence of respiratory quotient dynamic controlled atmosphere (DCA - RQ) and ethanol application on softening of Braeburn apples.

The effect of a respiratory quotient dynamic controlled atmosphere (DCA - RQ), which induces ethanol production through low oxygen storage, and ethanol application on softening of Braeburn apples stored at different temperatures was investigated. DCA - RQ storage was associated with the activation of the alcohol dehydrogenase (ADH) and greater anaerobic metabolism in comparison with DCA - CF (chlorophyll fluorescence) and controlled atmosphere (CA) storage. Greater anaerobic metabolism resulted in lower ethylene production, ACC oxidase activity, membrane permeability, -galactosidase activity and, therefore, less softening after long-term storage. Ethanol application after CA storage decreased ethylene biosynthesis, respiration rate and membrane permeability. Storage at 3 °C resulted in the lowest soluble solids and acidity, but not softening. In conclusion, Braeburn apples could be stored at 3 °C under DCA - RQ1.5. Additionally, ethanol produced by the fruit, or applied externally, had a significant effect on inhibiting softening during and after storage.

Key volatile compounds of 'Fuji Kiku' apples as affected by the storage conditions and shelf life: Correlation between volatile emission by intact fruit and juice extracted from the fruit.

For the 'Fuji Kiku' apple, this study aimed: (i) to evaluate the volatile compounds (VCs) from headspace storage chambers with static controlled atmosphere (CA) and with dynamic controlled atmosphere based on chlorophyll fluorescence (DCA-CF) and based on respiratory quotient (DCA-RQ1.5) at ninth month of storage, during 1 and 7 days of shelf life of intact fruit, and in apple juice headspace and (ii) to determine the correlation of the VCs in the headspace from storage chambers and fruit during shelf life with the headspace VCs from apple juice as markers of quality. The VCs were isolated by solid phase microextraction (HS-SPME) and analyzed by gas chromatography. In the storage chambers, ethyl linear chain esters were detected mainly in DCA-RQ1.5, while acetaldehyde and (E)-2-hexenal were more abundant in DCA-CF. At seven days of shelf life, fermentative metabolic compounds had reduced emissions given the opening time of the chamber, while there were higher emissions of branched chain esters, especially ethyl 2-methyl butanoate in DCA-RQ1.5. The correlation was high and positive between the VCs present in the juice and those emitted by the intact fruit during seven days of shelf life, demonstrating that the concentration of VCs in juice can be used to estimate the emissions from whole fruit. DCA-RQ1.5 storage promoted the synthesis of VCs typical of the 'Fuji' apple aroma after a prolonged storage period, even under extremely low partial pressure of oxygen (average 0.15 kPa), contributing to better quality control of characteristic fruit odor and aroma.

Pecan cultivation: general aspects / Pecanicultura: aspectos gerais da cultura

ABSTRACT: Given the increasing investment in the pecan production in southern Brazil, it becomes necessary researches, assisting in solve problems and proposition of technical and methodology to enhance this production chain. Thus, the present review aimed to survey the existing information about the culture, both on the world and the Brazilian scene. Issues related to botany, climate and soil requirements, alignment and planting density, cultivars, pests and diseases, among other technical aspects of this culture will be addressed. Pecan nut presents nutraceutical properties that are beneficial to human health, which has increased its demand from consumers. However, there are few research results with pecan nut in Brazil and there are many gaps in scientific knowledge about this culture, especially as regards the management of pests and diseases control, irrigation and nutrition, in Brazilian conditions.

RESUMO: Diante do crescente investimento na cultura da nogueira-pecã no sul do Brasil, torna-se necessário que a pesquisa atue auxiliando na solução de problemas e na proposição de técnicas e metodologia para potencializar esta cadeia produtiva. Desta forma, a presente revisão bibliográfica objetiva realizar um levantamento das informações existentes sobre a cultura, tanto no panorama mundial quanto brasileiro. Serão abordadas questões relacionadas com a botânica, exigências climáticas e edáficas, alinhamento e densidade de plantio, cultivares, pragas e doenças, entre outros aspectos técnicos da cultura. A noz apresenta propriedades nutracêuticas, que são benéficas para a saúde humana, o que tem aumentado a sua procura por parte dos consumidores. No entanto, são poucos os resultados de pesquisa com a cultura da nogueira no país e existem diversas lacunas no conhecimento científico sobre o cultivo da nogueira, principalmente, no que diz respeito ao manejo de pragas e doenças, irrigação e nutrição nas condições brasileiras.

Dynamic controlled atmosphere (DCA): interaction between DCA methods and 1-methylcyclopropene on 'Fuji Suprema' apple quality.

The objective of the present work was to evaluate the appropriate respiratory quotient (RQ) value to achieve a safe lowest oxygen limit (LOL), during storage of 'Fuji Suprema' apples, in dynamic controlled atmosphere (DCA), treated with or without 1-methylcyclopropene (1-MCP). The apples were stored in DCA-RQ, a new technology for storing fruits, and were compared with the HarvestWatch™, a system based on chlorophyll fluorescence DCA (DCA-CF), and static controlled atmosphere. DCA-RQ1.5 is the most suited for the storage of 'Fuji Suprema' apples. In this condition fermentative products were induced, which reduced ethylene production and respiration rate; however, it did not increase physiological disorders, and the concentration of ethyl acetate was below the odour threshold. 1-MCP application maintained higher flesh firmness and reduced the anaerobic metabolism, although it decreased fruit quality due to the occurrence of cavities, therefore its application is not recommended for 'Fuji Suprema' apple stored in DCA conditions.

Effects of dynamic controlled atmosphere by respiratory quotient on some quality parameters and volatile profile of 'Royal Gala' apple after long-term storage.

The effects of dynamic controlled atmosphere (DCA) storage based on chlorophyll fluorescence (DCA-CF) and respiratory quotient (DCA-RQ) on the quality and volatile profile of 'Royal Gala' apple were evaluated. DCA storage reduces ACC (1-aminocyclopropane-1-carboxylate) oxidase activity, ethylene production and respiration rate of apples stored for 9months at 1.0°C plus 7days at 20°C, resulting in higher flesh firmness, titratable acidity and lesser physiological disorders, and provided a higher proportion of healthy fruit. Storage in a regular controlled atmosphere gave higher levels of key volatiles (butyl acetate, 2-methylbutyl acetate and hexyl acetate), as compared to fruit stored under DCA-CF, but fruit stored under DCA-RQ 1.5 and RQ 2.0 also showed higher amounts of key volatile compounds, with increment in ethanol and ethyl acetate, but far below the odour threshold. Storage in DCA-CF reduces fruit ester production, especially 2-methylbutyl acetate, which is the most important component of 'Royal Gala' apple flavour.

Ethanol reduces ripening of 'Royal Gala' apples stored in controlled atmosphere.

This work aims at evaluate ethanol effect of acetaldehyde application in post-storage quality of 'Royal Gala' apples maintenance, and to compare them with consolidated storage techniques. Thus two experiments were performed during the years of 2008 and 2009. In the first experiment (2008), the application of ethanol, acetaldehyde or 1-MCP and ethylene scrubbing were tested. Fruits were stored in controlled atmosphere (CA) with 1.0kPa O2 and 2.0kPa CO2 at 0.5°C. In the second experiment (2009), the treatments tested were ethanol application combined or not with low relative humidity (LRH) and LRH alone. In this experiment, apples were stored in CA with 1.2kPa O2 + 2.5kPa CO2 at 0.5°C. After eight months of storage, 0.5 mL ethanol kg-1 apples month-1 or 0.25 mL acetaldehyde kg-1 apples month-1 increased mealiness, flesh browning, and decays incidence and reduced flesh firmness. In contrast, 0.3 mL ethanol kg-1 apples month-1, tested on second experiment, prevented fruit softening and decreased ACC oxidase activity and ethylene production. Although lower relative humidity was not efficient in maintaining post-storage quality, it enhanced the positive effect of ethanol application at 0.3 mL kg-1 apples month-1.

1-methylcyclopropene effects on volatile profile and quality of 'Royal Gala' apples produced in Southern Brazil and stored in controlled atmosphere / Efeito do 1-metilciclopropeno no perfil volátil e qualidade de maçãs 'Royal Gala' produzidas no Sul do Brasil e armazenadas em atmosfera controlada

ABSTRACT:Apple volatile aroma depends of complex interaction among organic compounds. The aim of the present study was to evaluate the effect of 1-methylcyclopropene (1-MCP) application on volatile profile and quality on 'Royal Gala' apples produced in Southern Brazil and stored under controlled atmosphere condition (CA; 1.0kPa O2+1.2kPa CO2; 0.5±0.1°C; 94±1% relative humidity). Volatile profile was determined after eight month of CA storage plus 7 days of shelf life via solid-phase microextraction (HS-SPME) and analyzed by gas chromatography coupled to mass spectrometer. In the volatile profile were identified 8 esters, 11 alcohols, 6 aldehydes, 6 acids, 2 ketones, 1 ether and 1 terpene. 1-MCP application reduced significantly the main volatile compounds production by 'Royal Gala' apples produced in Southern Brazil. Its application decreases significantly the esters production, especially 2-methyl-butyl acetate and hexyl acetate, compared to 'Royal Gala' apples storage under CA. 1-methylcyclopropene application decrease ethylene production and respiration rate. Apples treated with 1-MCP exhibit higher hexanal and 2(E)-hexenal production.

RESUMO:O aroma de maçãs depende de uma complexa interação entre compostos orgânicos. O objetivo do presente estudo foi avaliar o efeito da aplicação de 1-metilciclopropeno (1-MCP) sobre o perfil volátil e a qualidade de maçãs 'Royal Gala' produzidas no Sul do Brasil e armazenadas em atmosfera controlada (AC; 1,0kPa O2+1,2kPa CO2; 0,5±0,1°C; 94±1% umidade relativa). O perfil volátil foi determinado após oito meses de armazenamento mais seis dias de vida de prateleira através de micro extração em fase sólida (HS-SPME) e analisado por cromatografia gasosa acoplado a espectrofotômetro de massa. No perfil volátil, foram identificados 8 ésteres, 11 alcoois, 6 aldeídos, 6 ácidos, 2 cetonas, 1 éter e 1 terpeno. Aplicação de 1-MCP reduziu significativamente os principais compostos voláteis produzidos pela maçã 'Royal Gala'. Sua aplicação reduziu significativamente a produção de ésteres, especialmente 2-metil-butil acetato e hexil acetato, quando comparado à maçã 'Royal Gala' produzidas no Sul do Brasil e armazenada em AC. Aplicação de 1-metilciclopropeno reduziu a produção de etileno e respiração dos frutos. Maçãs tratadas com 1-MCP apresentam maior produção de hexanal e 2(E)-hexenal.

Dynamic controlled atmosphere and ultralow oxygen storage on 'Gala' mutants quality maintenance.

The aim of the present work was to compare the effect of ultralow oxygen (ULO) with dynamic controlled atmosphere (DCA) and controlled atmosphere (CA) on the post storage quality of 'Royal Gala' and 'Galaxy' apples after long-term storage. Two experiments were carried out with 'Royal Gala' and 'Galaxy' apples, in the years 2012 and 2013, respectively. A higher internal ethylene concentration was observed in fruits stored under CA; intermediate concentration in fruits under ULO; and the lowest by fruits stored under DCA-CF (DCA based on chlorophyll fluorescence). Flesh firmness was higher in fruits stored under DCA-CF and ULO differing from CA, in the year 2012, but in 2013 fruits stored under ULO showed the highest flesh firmness, differing from CA fruits. DCA-CF is efficient in quality maintenance of 'Royal Gala' and 'Galaxy' apples. Both 'Gala' mutants stored under ULO show a similar quality maintenance to those stored under DCA-CF.

Relative humidity during cold storage on Postharvest quality of 'Niagara Rosada' table grapes / Umidade relativa durante o armazenamento refrigerado sobre a qualidade pós-colheita de uvas de mesa 'Niagara Rosada'

This study aimed to evaluate the effect of different levels of relative humidity (RH) on the maintenance of Postharvest quality of 'Niagara Rosada' table grapes after cold storage at 0.5°C for 21 days. A completely randomized design was used, with five replicates of 18 clusters per treatment. The selected levels of relative humidity were 85, 90, 95 and 100%, obtained by means of electronic humidity controllers. The fruits were evaluated in relation to rot incidence, berry cracking, browning rate, respiratory rate, titratable acidity, soluble solids, resistance to abscission, berry drop and weight loss. The evaluations were assessed at 20 days of storage and after two and four days of shelf-life (20°C; 85% RH). The results showed that as higher as relative humidity, higher is rot incidence and that the variables rachis browning and weight loss were inversely related to relative humidity. Resistance to abscission at the end of storage was higher when humidity ranged between 90 and 95%, but it was not affected after transfer to shelf-life from cold storage. Relative humidity ranging between 90 and 95% offer the best conditions to maintain the Postharvest quality of 'Niagara Rosada' table grapes.

Este trabalho teve como objetivo avaliar o efeito de diferentes níveis de umidade relativa (UR) sobre a manutenção da qualidade pós-colheita de uvas de mesa 'Niagara Rosada', após armazenamento sob refrigeração, a 0,5°C durante 21 dias. Foi utilizado delineamento inteiramente casualizado, com cinco repetições de 18 cachos por tratamento. Os níveis de umidade relativa utilizados foram 85, 90, 95 e 100%, conseguidos com o auxílio de controladores eletrônicos. Os frutos foram avaliados quanto à incidência de podridões e rachaduras, índice de escurecimento, taxa respiratória, acidez titulável, sólidos solúveis, resistência ao degrane, degrane e perda de massa. As avaliações foram realizadas aos 20 dias de armazenamento e após dois e quatro dias de exposição dos frutos à condição ambiente (20°C; 85% UR). Os resultados indicaram que quanto maior o teor de umidade, maior a incidência de podridões, e que as variáveis escurecimento da ráquis e perda de massa possuem relação inversa à umidade relativa. A resistência ao degrane na saída da câmara foi maior com umidade entre 90 e 95%, mas não foi afetada após a transferência dos cachos à condição ambiente. O armazenamento sob refrigeração e umidade relativa na faixa de 90 a 95% proporciona melhor manutenção da qualidade pós-colheita de uvas 'Niagara Rosada'.

Tamanho de amostra para a estimação da média de caracteres de maçã / Sample size for estimate the average of characters in apples

O objetivo deste trabalho foi determinar o tamanho de amostra (número de frutos) necessário para a estimação da média de caracteres de maçãs Royal Gala e Fuji, avaliados na colheita e pós-colheita, após período sob armazenamento refrigerado. Em frutos de macieira Royal Gala e Fuji, foram mensurados oito caracteres na colheita e 11 caracteres após armazenamento refrigerado. Para cada caractere mensurado em cada cultivar, na colheita e após o armazenamento refrigerado, foram calculados a média, a variância, o coeficiente de variação, a assimetria, a curtose e verificada a normalidade e, em seguida, calculado o tamanho de amostra. Maior tamanho de amostra é necessário para a estimação da média de: produção de etileno, ratio, respiração, massa e acidez titulável. Menor tamanho de amostra é necessário para a mensuração de: diâmetro longitudinal, firmeza de polpa, sólidos solúveis totais, diâmetros transversais (maior e menor) e teor de suco. O tamanho de amostra necessário para a mensuração de caracteres de maçãs Royal Gala é menor em relação ao necessário para maçãs Fuji. Em maçãs Royal Gala e Fuji, 88 e 190 frutos, respectivamente, são suficientes para a mensuração de caracteres na colheita e após o armazenamento refrigerado, com erro de estimação de 5% da média.

The aim of this research was to determine the sample size (number of fruits) needed to estimate the average of Royal Gala and Fuji apples characters, evaluated at harvest and postharvest, after a period in cold storage. In Royal Gala and Fuji apples were measured eight characters at harvest and 11 after could refrigeration. For each character in each cultivar, measured at harvest and after cold storage, was calculated the mean, variance, coefficient of variation, skewness, kurtosis and checked the normality and, then, was calculated the sample size. Larger sample sizes are needed to estimate the average of: ethylene production, ratio, respiration, weight and acidity. Smaller sample sizes are needed for the measurement of longitudinal diameter, pulp firmness, total soluble solids, transversal diameters (major and minor) and juice content. The sample size required to measure the characters of Royal Gala apples is lower than that required for Fuji apples. In Royal Gala and Fuji apples, 88 and 190 fruits, respectively, are sufficient for the measurement of characters, at harvest and after cold storage, with estimation error of 5% of the average.

Effect of storage under extremely low oxygen on the volatile composition of 'Royal Gala' apples.

The aim of this work was to assess the profile of volatile compounds in 'Royal Gala' apples stored under controlled atmosphere (CA), with O(2) levels ranging from 1.0kPa to as low as 0.5kPa during 8months (0.5°C), followed by 7days of shelf-life at 20°C. Volatile compounds were collected via solid-phase microextraction (HS-SPME) and analysed by gas chromatography. Straight and branched-chain esters exhibited a distinct pattern. The emission of straight-chain esters decreased under extremely low O(2) (0.5kPa), while branched-chain esters were not significantly affected in such condition. 2-Methyl-butyl acetate, a significant contributor to the 'Royal Gala' aroma, was higher in intermediate O(2) concentration, suggesting that lowering the O(2) levels down to 0.7kPa does not negatively affect the volatile composition of 'Royal Gala' apples, as compared to the standard CA (1.0kPa O(2)). The remaining volatile compounds were not strongly affected by storing fruits under extremely low O(2).

Relative humidity and its interaction with the storage temperature of 'Gala' apples and mutants / Umidade relativa e sua interação com temperatura de armazenamento de maçãs 'Gala' e mutantes

The aim of this study was to evaluate the effect of relative humidity at two different temperatures on the postharvest quality of 'Gala', 'Royal Gala', 'Maxi Gala' and 'Brookfield' apples during eight months under controlled atmosphere storage. The experiment was conducted in a completely randomized design with split-plot scheme, where the main plots were composed of temperatures, 0.5 and 1.0°C, the subplots were the low (LRH) and high (HRH) relative humidity and the sub subplots were the four cultivars, resulting in a tri-factorial experiment: ((2x2) x4) with four repetitions of 25 fruits each. The results showed that there is a high respiratory rate in 'Maxi Gala' and 'Brookfield' apples in all storage conditions. The 'Brookfield' apples presented high pulp cracks when stored under a HRH environment. The temperature of 1.0°C decreases the ACC oxidase enzyme activity and ethylene production and maintains higher flesh firmness. The LRH maintains higher flesh firmness, total soluble solids and decreases the flesh breakdown. The fruits of the 'Brookfield' cultivar presented a lower storage potential in relation to the other cultivars.

O objetivo do presente estudo foi avaliar o efeito da umidade relativa em duas temperaturas sobre a qualidade pós-colheita de maçãs 'Gala', 'Royal Gala', 'Maxi Gala' e 'Brookfield' durante oito meses de armazenamento em atmosfera controlada. O experimento foi conduzido no delineamento inteiramente casualizado com parcela subsubdividida, sendo as temperaturas de 0,5 e 1,0°C as parcelas principais, a baixa umidade relativa do ar (BUR) e alta umidade relativa do ar (AUR) as subparcelas e as quatro cultivares as subsubparcelas, resultando num experimento trifatorial: ((2x2) x4) com quatro repetições de 25 frutos em cada. Pelos resultados, observa-se uma elevada taxa respiratória nos frutos das cultivares Maxi Gala e Brookfield em todas as condições testadas. Os frutos da cultivar Brookfield apresentaram maior rachadura de polpa quando estes foram armazenados em ambiente com AUR. A temperatura de 1,0°C diminui a atividade da enzima ACC oxidase, a produção de etileno e mantém maior firmeza de polpa. A BUR mantém maior firmeza de polpa, sólidos solúveis totais e diminui a degenerescência de polpa. Os frutos da cultivar Brookfield apresentam menor potencial de armazenagem em relação às demais cultivares.

Aplicação de 1-metilciclopropeno, estresse inicial com baixo oxigênio e armazenamento em ultrabaixo oxigênio na qualidade de maçã Fuji / Application of 1-methylcyclopropene, initial low oxygen stress and storage in ultralow oxygen on Fuji apples quality

O objetivo deste trabalho foi avaliar o efeito da aplicação de 1-MCP em combinação com condições de estresse inicial com baixo O2 e armazenamento em atmosfera controlada com pressões parciais ultrabaixas de O2 sobre a manutenção da qualidade de maçãs Fuji. Os tratamentos avaliados foram com e sem aplicação de 1-MCP (1.000nL L-1), combinado com cinco níveis do fator condição de armazenamento (sem estresse inicial + 0,6kPa O2, 1 estresse + 0,6kPa O2, 1 estresse + 0,8kPa O2, 2 estresses + 0,6kPa O2 e sem estresse inicial + 1,0kPa O2). Cada estresse inicial foi com 0,2kPa de O2 pelo período de 14 dias. Os frutos foram armazenados nessas condições durante oito meses a -0,5°C±0,2°C e UR de 96±1%, mais sete dias de exposição a 20±1°C. Em todos os tratamentos, o CO2 foi mantido abaixo de 0,5kPa. O armazenamento sem estresse inicial por baixo O2 associado a 1,0kPa ou 0,6kPa de O2 manteve a polpa mais firme e com maior acidez titulável. Além disso, proporcionou menor ocorrência de podridão após oito meses de armazenamento mais sete dias a 20°C. O 1-MCP proporcionou menor atividade da enzima ACC oxidase, no entanto, não foi eficiente para a redução da produção de etileno e para retardar a perda da firmeza e a ocorrência de podridão. O estresse inicial de 14 dias com 0,2kPa de O2 prejudicou a conservação de maçãs Fuji.

The aim of this research was to evaluate the effect of 1-MCP application in combination with initial low oxygen stress and storage in controlled atmosphere with ultra-low oxygen on Fuji apple quality preservation. The evaluated treatments consisted of 1-MCP application (with or without 1000nL L-1) combined with five levels of the factor storage condition (without initial stress + 0.6kPa O2, 1 stress + 0.6kPa O2, 1 stress + 0.8kPa O2, 2 stresses + 0.6kPa O2 and without initial stress + 1.0kPa O2). Initial low oxygen stress was applied by 14 days at 0.2kPa O2. The fruits were stored in these conditions for eight months at -0.5±0.2°C and relative humidity of 96±1%, followed by seven days at 20±1°C. In all treatments, the CO2 was kept below 0.5kPa. The storage without initial low oxygen stress associated with 1.0kPa or 0.6kPa O2 maintained the pulp firmer and with the higher titratable acidity, moreover provided a lower incidence of decay after storage during eight months and shelf life at 20°C. The 1-MCP provided lower activity of ACC oxidase enzyme, however, did not reduces ethylene production and failed to delay the loss of firmness and the control decay. Initial stress of 14 days with 0.2kPa O2 reduced the conservation of Fuji apples.

Tamanho de amostra para a estimação da média de caracteres de pêssego na colheita e após o armazenamento refrigerado / Sample size to estimate the average peach characters at harvest and after cold storage

O objetivo deste trabalho foi determinar o tamanho de amostra necessário para avaliar caracteres de frutos de pêssego na colheita e após o armazenamento refrigerado. Foram colhidos frutos de um pomar comercial. No laboratório, separaram-se, aleatoriamente, duas amostras de 120 frutos de pêssego, sendo uma amostra avaliada na colheita e a outra armazenada a -0,5°C por 30 dias, mais cinco dias a 20°C. Foram mensurados 11 caracteres em cada fruto na colheita e 12 caracteres após o armazenamento refrigerado, sendo calculadas medidas de tendência central e de dispersão e verificada a normalidade. Posteriormente, compararam-se as médias e verificou-se a homogeneidade de variâncias dos caracteres avaliados na colheita e após o armazenamento refrigerado. A seguir, foi determinado o tamanho de amostra para cada caractere. São necessários 169 frutos para estimar a firmeza de polpa, 34 frutos para estimar a massa, a acidez e o ratio, 11 frutos para avaliar a suculência e seis frutos para estimar os demais caracteres na colheita e após o armazenamento refrigerado, com erro de estimação de 5 por cento da média.

The aim of this research was to determine the sample size needed to evaluate peach fruit characters at harvest and after cold storage. Fruits were collected from a commercial orchard. In the laboratory, split randomly, two samples of 120 fruits each, one sample assessed at harvest and one stored at -0.5°C for 30 days, and then for five additional days at 20°C. Eleven characters were measured on each fruit at harvest and twelve after cold storage, being the central tendency measures and dispersion calculated and normality checked. After, it was compared the average and the homogeneity of variance at harvest and after cold storage and calculated the sample size for each character. In peach, 169 fruits are needed to estimate the pulp firmness, 34 fruits to estimate the weight, acidity and ratio, 11 fruits to assess fruit juiciness and six fruits to estimate the others characters at harvest and after cold storage, with an estimation error of 5 percent on average.

Aplicação de 1-metilciclopropeno e absorção de etileno em maçã da cultivar 'Royal Gala' colhida tardiamente / Application of 1-methylciclopropene and ethylene absorption on 'Royal Gala' apple late harvested

O objetivo deste trabalho foi avaliar a perda da eficiência do controle do etileno com o uso de 1-MCP e da sua absorção ao longo do período de oito meses de armazenamento em atmosfera controlada (AC) de maçãs da cultivar 'Royal Gala' colhidas em estádio de maturação avançado. Os frutos foram colhidos com firmeza da polpa de 89,5N; índice de iodo-amido de 6,7; acidez de 5,06meq 100mL-1; teor de sólidos solúveis de 11,8°Brix; produção de etileno de 0,721µL C2H4 kg-1 h-1; e respiração de 6,61mL CO2 kg-1 h-1. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro tratamentos e seis repetições. Os frutos foram armazenados na temperatura de 0,5°C (±0,1), sendo avaliadas as seguintes condições: [1] AC com 1,2kPa O2 + 2,5kPa CO2; [2] AC com aplicação de 1µL L-1 de 1-MCP; [3] AC com aplicação de 1µL L-1 de 1-MCP e de 10µL L-1 de etileno (AE); e [4] AC com baixa concentração de etileno (<0,1µL L-1) (BE). O 1-MCP não apresentou eficiência na conservacão da firmeza da polpa em maçãs colhidas em estádio de maturação avançado, mas manteve eficiência na redução da atividade da enzima ACC oxidase, produção de etileno e atividade respiratória dos frutos.

The aim of this research was to evaluate the efficiency of the control of ethylene with 1-MCP application and its absorption in 'Royal Gala' apple fruit harvested at advanced maturity stages, during eight months of storage under controlled atmosphere (CA). The fruits were harvested with pulp firmness of 89.5N; iodine-starch índex of 6.7; acidity of 5.06meq 100mL-1; soluble solids content of 11.8°Brix; ethylene production of 0.721µL C2H4 kg-1 h-1 and respiration of 6.61mL CO2 kg-1 h-1. The experimental design was completely randomized with four treatments and six replications. The fruits were stored at 0.5°C, being evaluated at the following conditions: [1] CA with 1.2kPa O2 + 2.5kPa CO2, [2] CA with application of 1µL L-1 of 1-MCP, [3] CA with application of 1µL L-1 1-MCP and 10µL L-1 of ethylene, and [4] CA with low ethylene concentration (<0.1µL L-1). 1-MCP did not have effect on pulp firmness in apple fruit harvested at advanced maturity stage but reduced the activity of ACC oxidase, ethylene production and respiratory activity of the fruits.