Titratable Acidity Ratio Research Articles

1-Methylcyclopropene 처리시기가 모의유통기간 중 'Fuji' 사과의 품질에 미치는 영향

This study was evaluated the effect of 1-methylcyclopropene (1-MCP) treatment on fruit quality of ‘Fuji’ apples during shelf life condition at room temperature (RT) after cold storage. Fruits were treated with 1-MCP at 0, 1st, and 2nd day after harvest, stored at 0°C cold storage for 3 months and assessed after 10, 20, and 30 days in RT shelf life condition after cold storage. After 30 days in RT, flesh firmness of untreated fruits was decreased to 45.8 Newton (N), while all of 1-MCP-treated fruits were maintained at 61.8-64.3 N. Internal ethylene concentration was sharply increased to 177.93 μL/L in untreated fruits, while it was inhibited by all of 1-MCP treatments at 0.74-3.06 μL/L. Titratable acidity (TA) was decreased to 0.19% in untreated fruits and all of 1-MCP treatments slowed the decrease of TA at 0.24-0.28%. The soluble solids content / titratable acidity (SSC/TA) ratio was gradually increased in untreated fruits, but it was not significantly changed in 1-MCP treatments. In addition, lightness of fruit peel color was maintained greater by 1-MCP treatments. Therefore, the results suggested the storability of untreated fruits was limited to 10 days in RT, but 1-MCP treatment extended the storability of ‘Fuji’ apples up to 30 days in shelf life condition at RT after cold storage.

Comparison of fruit quality traits of papaya (Carica papaya L.) genotypes from Shushufindi and La Joya de los Sachas, Ecuador

In the northern region of the Ecuadorian Amazon, there are papaya genotypes with acceptable production and fruit quality traits; however, they are heterogeneous. The aim of this research was to evaluate papaya genotypes for the selection of individuals through fruit quality traits. The study was carried out at the Central Amazon Experimental Station of Instituto Nacional de Investigaciones Agropecuarias, located in the canton La Joya de los Sachas, Orellana Province. A completely randomized design with a different number of observations according to the number of individuals per genotype was used. The recorded variables were: fruit weight (kg), pulp weight (kg), peel weight (kg), fruit diameter (cm), fruit length (cm), pulp thickness (cm), fruit firmness (kg-f), pH, total soluble solids (°Bx), titratable acidity, and flavor ratio. Data were subjected to one-way analysis of variance, mean comparison tests (Tukey 95%) for dendrograms, correlation matrix, and Biplot graphs. Results showed individuals with high production (more than 50 fruits/plant) and fruits with market demanded traits for fresh consumption (fruit weight between 0.2 and ≥ 2.0 kg, and soluble solids content ≥ 11.5 °Bx). In addition, ten elite individuals were identified as they meet the dual production and fruit quality traits, and must be considered for future breeding programmes.

Characterization of physiological maturity of Physalis peruviana L. fruits

Physalis peruviana L. has great nutritional value and economic viability, representing an innovation for Brazilian horticulture. However, knowing the ideal point of harvesting fruits of this species is a key factor in this process that allows maximum post-harvest utilization, providing better quality and minimal losses when the fruit is harvested at physiological maturity. Therefore, this study was conducted to characterize the physiological maturity of Physalis peruviana L. fruits. The experiment was laid out in a completely randomized design in which the treatmentscorresponded to different stages of fruit and seed maturation (20, 27, 34, and 41 days after anthesis [DAA]), with four replicates. The analyzed variables consisted of colorimetry (lightness, chroma and hue angle) of calyx and fruit; fresh weight, diameter (transverse and longitudinal), firmness, pH, total soluble solids, titratable acidity, total soluble solids:titratable acidity ratio, vitamin C and phenolic compounds of fruits; and carotenoids and chlorophyll (a and b) of calyx. The obtained data were subjected to analysis of variance and polynomial regression. Fruits intended for consumption must be harvested after 35 DAA, at which time yellow color and excellent organoleptic and nutritional qualities were observed.

Can environment and genotype influence sweet cherry qualitative parameters?

The sweet cherry fruit quality traits (soluble solid content, titratable acidity, pH and soluble solid titratable acidity ratio), phytochemical content (total phenolic content and total monomeric anthocyanins) and antioxidant activity were determined in five Italian autochthonous genotypes and compared with two commercial cultivars for 4 consecutive years. Significant influences of genotype, crop year and their interaction on the variables under study was observed. The autochthonous cultivar “Ciliegia di Udine”, on average, showed the highest values for all the investigated parameter whereas the lowest ones were reported for the largely cultivated cultivar “Ferrovia” (Germersdorfer). Beside the genotype, crop year and its climatic conditions affected fruits quality and “Flamengo Srim” showed the best response taking into consideration fruit quality traits, phytochemical content and antioxidant activity and their quali-quantitative stability across the experimentation.

Juice attributes of Ontario-grown culinary (dessert) apples for cider

Continued interest in the commercial production of cider in Ontario has revealed that there is a lack of information available to apple producers and cidermakers on the juice attributes of culinary dessert apple for making cider and how they may vary from orchard to orchard. A two-year study was conducted to characterize the juice characteristics of 18 common culinary dessert apple cultivars grown at several locations in Ontario. Juice was assayed for soluble solids concentration, pH, titratable acidity (TA), juice extraction efficiency, yeast assimilable nitrogen (YAN), polyphenols, and soluble solids to TA ratio. Significant differences among cultivars were observed for all parameters, which varied by orchard and year, except juice extraction efficiency. These data underly the importance of assaying juice every growing season prior to fermentation. Cidermakers should focus on juice characteristics from culinary apples that are more difficult to alter (with amendments), and use juice with lower pH, higher TA and polyphenols, and moderate to higher YAN to optimize cider quality and flavour. Overall, this study will inform cidermakers of which culinary apple cultivars might be preferable for fermentation as well as how they might be blended to optimize cider quality. Notwithstanding annual and orchard variation, cultivars that meet these criteria include Cortland, Crimson Crisp, Honeycrisp, Jonagold, McIntosh, and Northern Spy. If making cider from Ambrosia, Crispin, Empire, Fuji, Gala, Golden Delicious, or Idared, cidermakers should expect to blend the juice from these cultivars to create a more fully balanced juice prior to fermentation.

Chemical characterization in the selection of Italian autochthonous genotypes of plum

Plums are climacteric fruits with edible fleshy mesocarp. They belong to different species of the genus Prunus (Rosaceae) and consist of many autochthonous genotypes characterized by particular organoleptic characteristics and nutraceutical potential. In this study, chemical properties (i.e., soluble solid content, pH, titratable acidity, total phenolic content and antioxidant activity) of seventeen plum genotypes (four largely diffused varieties plus one clone and thirteen autochthonous genotypes) were investigated during six crop years. A discrimination among the genotypes, with respect to ripening time, pomological and nutraceutical traits, was obtained applying hierarchical cluster analysis (HCA). In addition, a principal component analysis (PCA) was calculated to evaluate the genotypes similarity and stability during the six crop years. Finally, correlation studies among all traits and crop year’s meteorological conditions were also investigated. The results showed significant differences in chemical properties in relation to the genotype, crop years and ripening time highlighting higher titratable acidity, total phenolic content and antioxidant activity in autochthonous genotypes. Contrary, the largely diffused cultivars (or commercial varieties) showed the highest soluble solid content and the lowest acidity values. HCA and PCA allowed to discriminate the autochthonous plum genotypes ‘Regina Claudia’, ‘Prungaccino di Velletri’ and ‘Prugna di Drò’ considering their phenols amount and stability across the six crop years. In many cases, their concentrations resulted higher than those found in the commercial varieties ‘D’Ente 707’, ‘French Prune’ and ‘Stanley’, maintaining good soluble solid content and titratable acidity ratio (SSC/TA). Finally, hierarchical cluster analyses for SSC and TA traits plotted the samples in relation to ripening time. These results could promote specific autochthonous genotypes, to establish a database that could permit to improve the utilization of specific genetic resources in breeding programs.

Overall quality maintenance of grapefruit during cold storage using pre-storage neem leaf extract dipping

The present studies were conducted to investigate the effects of different concentration of neem leaf extract (NLE) (control, 10%, 20% and 30%) on physiological, biochemical, antioxidant properties, and fruit quality attributes of Shamber grapefruit during cold storage at 10 °C up to 43 days. Weight loss, peel weight, juice weight, rag weight, ascorbic acid, total sugars (TS), reducing sugars (RS), non-reducing sugars (NRS), total soluble solids (TSS), titratable acidity (TA), TSS/TA ratio and enzyme activities such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were determined. NLE treatments showed significant effect on postharvest quality attributes of Shamber grapefruit. NLE-treated grapefruit (30%) reduced the weight loss (16%), and retained maximum peel weight (9.02%), juice weight (25.56%) and rag weight (19.21%) than untreated control fruit. Moreover, high level of ascorbic acid, TSS, TA, and lower level of TS, RS and NRS were observed in NLE (30%) treated fruits. Enzymatic activities of SOD, POD and CAT of stored grapefruit were highly significant in NLE (30%) treated grapefruit during storage period compared to control. In conclusion, pre-storage NLE (30%) application was the most effective in maintaining various physiochemical properties such as weight loss, ascorbic acid, TS, RS, NRS, TSS, TA, TSS:TA ratio and increasing the antioxidative responses (SOD, POD and CAT) up to 43 days by extending the shelf life of Shamber grapefruit.

Evaluation of postharvest properties in different passion fruit species during ripening

During ripening, many transformations occur in passion fruits. The ripening stage affects fruit quality and post-harvest properties. Fruits with 65% yellow epidermis present chemical characteristics that meet industrial standards, facilitating harvest estimations and loss avoidance. Thus, this study aimed to evaluate the post-harvest properties of passion fruit species (genotypes of the yellow passion fruit and sweet passion fruit, and yellow passion fruit cultivar FB 200) during ripening. The fruits were evaluated by the color of the epidermis and the chemical characteristics of the pulp (titratable acidity, vitamin C, carotenoids, soluble solids content, and ratio). This experiment was conducted with a completely randomized design and a split-plot arrangement, where the plots were the species and the subplots were the evaluation periods (50, 58, 66, 74 and 82 days after anthesis), with four replications and 10 fruits per plot. The yellow passion fruit genotype and cultivar, harvested at 82 days after anthesis, presented desirable characteristics for the juice industry and for fresh consumption. The sweet passion fruit had a higher soluble solids content and titratable acidity ratio because of its high content of soluble solids and low acidity, which translate to a better fruit flavor.

ВЛИЯНИЕ СПОСОБОВ ВЕДЕНИЯ СОРТА КРАСНОСТОП АЗОС И ЕГО НАГРУЗКИ НА УРОЖАЙНОСТЬ И КАЧЕСТВО ВИНОГРАДА И ВИНА ИЗ НЕГО

The qualitative characteristics of technical grapes and wine largely depend on the system of this crop. The objects of research were grapes and wine material of the Krasnostop AZOS variety in grafted and own-rooted cultures with variants of different loads of shoots on a bush. The experience of studying the influence of various agrotechnical methods on the productivity of a grape plant and the quality of wine material was laid down in the Anapo-Taman climatic zone of the Krasnodar Territory of Russia. The largest yield of the Krasnostop AZOS variety during the years of the study was obtained in the variant of own-rooted grape cultivation with its load of 36-40 shoots per bush. In our studies, there is a tendency to increase the sugar content and reduce the titratable acidity of grapes when maintaining vineyards of the Krasnostop AZOS variety in own-rooted culture. The most optimal ratio of sugar content and titratable acidity in the experiment had grapes from the variant of own-rooted culture with a load of shoots of 36-40 pcs/bush. In the studied variants, the largest amount of phenolic substances was found in wine material from own-rooted grapes with a load of 36-40 shoots per bush - 4130 mg/dm3. The maximum total content of substances from a number of biologically active substances was found in wine from grape raw materials obtained from a grafted culture (134.9 - 147.9 mg/dm3). In 2018-2019, from the organoleptic side, wine materials from own-rooted grapes proved to be of the highest quality.

Application of Ultrasound Combined with Acetic Acid and Peracetic Acid: Microbiological and Physicochemical Quality of Strawberries.

This work evaluated the application of organic acids (acetic and peracetic acid) and ultrasound as alternative sanitization methods for improving the microbiological and physicochemical qualities of strawberries. A reduction of up to 2.48 log CFU/g aerobic mesophiles and between 0.89 and 1.45 log CFU/g coliforms at 35 °C was found. For molds and yeasts, significant differences occurred with different treatments and storage time (p < 0.05). Ultrasound treatments in combination with peracetic acid and acetic acid allowed a decimal reduction in molds and yeasts (p < 0.05). All evaluated treatments promoted a significant reduction in the Escherichia coli count (p < 0.05). Scanning electron microscopy revealed fragmented E. coli cells due to treatment with acetic acid and ultrasound. Storage time significantly affected pH, total titratable acidity, total soluble solids and the ratio of the total titratable acidity to the total soluble solids (p < 0.05). Anthocyanin content did not change with treatment or time and generally averaged 13.47 mg anthocyanin/100 g of strawberries on fresh matter. Mass loss was not significantly affected by the applied treatments (p > 0.05). The combination of ultrasound and peracetic acid may be an alternative to chlorine-based compounds to ensure microbiological safety without causing significant changes in the physicochemical characteristics of strawberries.

Cultivo do tomateiro em ambiente protegido sob diferentes tensões de água no solo

Diferentes cultivares de tomateiro podem apresentar necessidades hídricas diferenciadas, tornando-se indispensável o estudo da demanda hídrica. Desta forma, objetivou-se avaliar a influência de diferentes tensões de água no solo sobre a produção e qualidade pós-colheita de frutos do tomateiro, cultivar Dominador F1, sob cultivo protegido e irrigado por gotejamento. O experimento foi instalado em casa de vegetação com delineamento em blocos casualizados, com quatro repetições. Os tratamentos foram constituídos por seis tensões de água no solo como indicativos do momento de irrigar. As tensões preestabelecidas foram 20, 45, 70, 95, 120 e 145 kPa a 20 cm de profundidade. Aos 140 dias após o transplantio as variáveis avaliadas foram: produção total, comercial e não comercial de frutos; produtividade total, comercial e não comercial de frutos; número de frutos por planta; classificação dos frutos comerciais; massa média dos frutos comerciais; incidência de podridão apical (%); eficiência no uso da água (EUA); acidez titulável (AT); sólidos solúveis totais (SST); pH; relação sólidos solúveis totais e acidez titulável (SST/AT); pectina solúvel; vitamina C; firmeza; coloração e teor de macro e micronutrientes da parte aérea. Os resultados demonstraram que para a obtenção dos maiores valores de produção e produtividade de frutos comerciais, número de frutos por planta, número de frutos grandes e médios e massa média de frutos comerciais, deve-se irrigar quando a tensão de água no solo estiver, em torno, de 20 kPa, à profundidade de 0,20 m. As diferentes tensões de água no solo não influenciaram, significativamente, a acidez titulável, pH, relação sólidos solúveis totais e acidez titulável e pectina solúvel. A eficiência no uso da água, em função das tensões de água no solo, aumentou até a tensão de 116,57 kPa. Das características de qualidade avaliadas, os teores de sólidos solúveis totais, de vitamina C, firmeza e índice L* de coloração, apresentaram efeito significativo com as tensões de água no solo.

Post-harvest study of ‘paluma’ guavas (Psidium guajava L.) coated with biodegradable films with and without essential oil association

Neste trabalho buscou-se avaliar a eficiência de películas biodegradáveis, elaboradas a partir da fécula de mandioca associada ou não com óleo essencial da casca de laranja ‘Pêra’ (OECL) (Citrus sinenses L.) na vida de prateleira em goiabas “Palumas” (Psidium guajava L.). Para isso, foi extraído e avaliada a qualidade do OECL aplicado na elaboração de película biodegradável a base de fécula de mandioca. As goiabas utilizadas foram submetidas aos tratamentos: Controle, sem revestimento = T1, com revestimento de fécula de mandioca a 2% (FM) sem associação com óleo essencial da casca da laranja = T2 e com revestimento de FM a 2% + associação de óleo essencial de casca de laranja = T3. O estudo foi realizado em 2 lotes totalizando 42 frutos analisados, dispostos em uma câmara climatizada com temperatura de 25 ± 2 ºC e UR de 90 ± 2%, permanecendo por um período de até 12 dias, sendo realizadas as análises físico-químicas de pH, acidez total titulável (ATT), sólidos solúveis totais (SST), relação sólidos solúveis totais e acidez total titulável (rátio), vitamina C, firmeza do fruto, perda de massa, cor da polpa, cor da casca e análise microbiológica de bolores e leveduras realizadas nos tempos 0, 2, 4, 6, 8, 10 e 12 dias, em um fruto correspondente a cada tratamento. As películas não apresentaram melhoria nos parâmetros avaliados, em comparação com as goiabas desprovidas de revestimento (T1). Desta forma, películas biodregadáveis elaboradas em condições similares não são recomendada para melhorias no tempo de prateleiras em goiabas “Palumas” (Psidium guajava L.).

Enhancement of antioxidant and storability of Hollywood plum cultivar by preharvest treatments with moringa leaf extract and some nutrients

BackgroundPlum fruit has a short shelf life with a rapid deterioration in quality after harvest. The main aim of this study was to evaluate the effect of preharvest treatments by moringa leaf extract (MLE), boric acid (B), and chelated calcium (Ca EDTA) on Hollywood plum fruit quality attributes bioactive compounds and antioxidant activity during cold storage. Plum trees were sprayed twice: at full bloom stage and 1 month later with T1, 5% MLE + 1% B + 2% Ca EDTA; T2, 5% MLE + 2% B + 3% Ca EDTA; T3, 10% MLE + 1% B + 2% Ca EDTA; T4, 10% MLE + 2% B + 3% Ca EDTA; and T5, water only as control. At maturity stage, fruits were harvested and stored at 0 ± 1 °C and RH 85–90% for 8 weeks.ResultsAt the end of storage, all studied treatments exhibited significantly higher sensory quality: firmness, color, soluble solid content:titratable acidity ratio, total anthocyanin content, total flavonoids content, total phenolic content, and antioxidant activity than control.ConclusionsIt could be concluded that preharvest treatment with moringa leaf extract, boric acid, and chelated calcium could be a safe and eco-friendly to improve and maintain plum quality attributes and especially their content of antioxidant compounds during cold storage periods.

SOIL MULCHING AND DEFICIT IRRIGATION WITH WASTEWATER IN THE QUALITY OF ITALIAN ZUCCHINI

Conscious agricultural management, which aims to conserve natural resources, has been the target of contemporary agriculture. In this context, the reuse of water in deficit water depth in agricultural irrigation becomes a viable technique, and this work aimed to evaluate the effect of different irrigation depths with wastewater and soil mulching on the microbiological and postharvest characteristics of the Italian zucchini. The experiment was conducted in the field conditions with a randomized block design in a split-plot arrangement. Four irrigation depths (100%, 85%, 70%, and 55% of the estimated ETc from the Class A Evaporation Pan) and three types of soil mulching (rice husk, double-sided black and white polyethylene film, and uncovered soil) were analyzed. Texture, titratable acidity (TA), soluble solids content (ºBrix), pH, and the ºBrix:TA ratio of the Italian zucchini were analyzed, besides the microbiological analysis. The irrigation depth or soil mulching did not influence the pH of the Italian zucchini. The uncovered soil promoted higher titratable acidity to the Italian zucchini. The texture of the fruit, the soluble solids, and the ºBrix:TA ratio was influenced by the types of soil mulching and irrigation depths. The use of wastewater for drip irrigation reduces the effects of the microbial load on the crop.

Prospection of the quality and bioactive potential of the seedless watermelon

The present investigation aimed to evaluate the prospection of the quality and the bioactive potential of four seedless watermelon hybrids. Fruits were collected from the commercial farms located at the Jaguaribe-Açu agricultural Valley/RN and Jaguaribe Valley/CE, Brazil. Plant material included the hybrids 'Ashira', 'Extasy', 'Mickylee' and 'Valentino'. The following parameters were evaluated: fruit weight; longitudinal and transverse diameter; fruit shape index; pulp firmness; pulp color; shell thickness; soluble solids, titratable acidity, pH, soluble solids and titratable acidity ratio, total and reducers soluble sugars, vitamin C, total carotenoids, lycopene, yellow flavonoids, total anthocyanins and total polyphenols. The trial was carried out by a completely randomized design. The comparison of means was performed using one way ANOVA at the Tukey HSD test. All the hybrids showed fruits small, i.e., “icebox” type, with mean values lower than 5.5 kg, spherical shape and a higher portion of edible pulp. The fruits showed high pulp firmness leading a great resistance to mechanical injuries sustained due to transport, besides long postharvest shelf life. 'Ashira' showed the highest proportion of sugars present in the fruit due to the increase of 73% in the SS/AT ratio compared to the other hybrids. 'Extasy' presented high content of total carotenoids whereas 'Ashira' stood out in the content of total polyphenols. The hybrids are promising alternatives to the local and export watermelon market, in view of the high quality and bioactive potential linked to the good adaptability and stability under the growth conditions.

Nitrogen Fertilization and Liming Improves Growth, Production, Gas Exchange and Post-Harvest Quality of Yellow Flower Jambu

Jambu is a vegetable, widely consumed in the Brazilian North Region, both in typical foods and medicinal herb. Despite its versatility, there are uncountable challenges in relation to its cultivation, especially with regard to the availability of information on nutritional management, such as the lack of data on the effect of liming associated with the supply of nitrogen (N) on the production performance of the crop. Thus, the effect of nitrogen fertilization and liming on growth, production, physiological responses and post-harvest quality of the yellow-flowered variety jambu was evaluated. The experimental design was randomized in factorial blocks (6 x 2), with five repetitions. The treatments consisted in the combination of six doses of N (0; 60; 90; 120; 150 and 180 kg ha-1) with and without liming application (0 and 70% V). The variables of growth, production, gas exchange and post-harvest quality of jambu were evaluated. Standardly, there was interaction between N-dose and liming factors for most of the analyzed variables, except for titratable acidity and total soluble solids and titratable acidity ratio. In general, the increasing of N doses combined with liming positively affected growth, production, physiological responses and post-harvest quality, and it was observed that in the 170 kg ha-1 dose of N higher response was obtained in the biomass accumulation of the aerial part and in the 180 kg ha-1 dose of N maximum production of inflorescences. Therefore, the use of correctives associated with nitrogen fertilization is recommended to obtain more significant production and quality of jambu.

Poda de renovação para segundo ciclo produtivo e origem da muda de morangueiro

O objetivo deste experimento foi avaliar a produção e qualidade de frutas do morangueiro no segundo ciclo produtivo, submetida a diferentes épocas de poda de renovação da cultivar San Andreas a partir de mudas chilenas e espanholas, sob cultivo em substrato. O experimento foi realizado no município de Bom Princípio, Rio Grande do Sul. Foram utilizadas mudas provenientes de duas origens: Espanha e Chile, as quais foram submetidas a épocas de poda de renovação, realizadas nos dias 20/01, 10/02, 01/03, 20/03 de 2018. A testemunha caracterizou-se pela ausência de poda, sendo realizada a retirada de folhas senescentes, no dia 20/01. O experimento foi um fatorial 2x5, em blocos ao acaso com quatro repetições e cada repetição contendo 10 plantas. Na poda de renovação foram deixadas três coroas por planta e mantidas as duas folhas mais jovens em cada coroa. A colheita das frutas teve início em 20 de março, estendendo-se até 22 de outubro de 2018, sendo colhidas, pesadas e classificadas em frutas comerciais e não comerciais. Mensalmente, durante os meses de julho a outubro, foram coletadas cinco frutas por parcela, nos quais avaliou-se diâmetro e comprimento, teor de sólidos solúveis, acidez titulável, firmeza de polpa e relação sólidos solúveis/acidez titulável. A data de realização da poda de renovação e a origem das mudas não influenciaram no número de frutas, massa fresca e massa média de fruta. O mês de agosto apresentou qualidades físico-químicas melhores em relação aos demais meses.

Pre-storage fumigation with hydrogen sulphide inhibits postharvest senescence of Valencia and Navel oranges and ‘Afourer’ mandarins

ABSTRACT A short, pre-storage fumigation with hydrogen sulphide (H2S) gas at 0, 100, 250 and 500 µL L−1 affected development of a range of senescence characteristics of Navel and Valencia oranges and ‘Afourer’ mandarins during storage at 20°C for five weeks. The greatest beneficial effect was observed with fumigation at 100 µL L−1 H2S which resulted in reduced incidence of calyx drop, calyx browning and fungal decay and production of ethylene and ethanol for all three citrus species. For Valencia oranges, a lower total soluble solids (TSS): titratable acidity (TA) ratio was observed, arising from both a lower TSS and higher TA than in control fruit. H2S treatment had no significant effect on the respiration rate in any fruit species. In general, higher concentrations of H2S were less effective than 100 µL L−1 and often resulted in accelerated loss of quality. The results suggest that H2S fumigation of citrus prior to storage may be an alternative treatment for delaying the emergence of senescence characteristics such as calyx browning without the use of synthetic auxins.

DETERMINATION OF THE MATURATION STAGE AND CHARACTERISTICS OF THE FRUITS OF TWO POPULATIONS OF Passiflora cincinnata Mast

ABSTRACT Passiflora cincinnata Mast. (caatinga passion fruit) has acidic fruits with a peculiar flavor, green color when ripe and a low percentage of abscission making it difficult to identify the point of harvest. In order to verify the harvest period in two populations of P.cincinnata, flowers were marked in anthesis and after six periods the fruits were harvested. This study evaluated fruit mass, seeds and pulp mass, fruit dimensions and shape, percentage of water, color and texture of skin, volume, color and pulp yield, pH, soluble solids (SS), titratable acidity ratio, polyphenol content, flavonoids and anthocyanins. The assay was designed in a completely randomized design in a factorial arrangement (2x6), with two populations (CPEF2220 and CBAF2334) and six harvest periods (20, 40, 60, 80, 100 and 120 days after anthesis - DAA) with four repetitions. There was a reduction in thickness (43.1%) and percentage of water in the skin (9.3%), pH (40.1%), ratio, polyphenols content and pulp luminosity (brightness). There were increases in pulp mass and volume, seed mass, pulp mass yield in relation to the fruit (72%), and SS titratable acidity (44.9%) in CPEF2220 and equality between populations in fruit shape, pulp color, thickness and skin color (luminosity and ºhue), pH and polyphenols. Although after 100 DAA there were higher yields, between 60 and 80 DAA it was possible to identify characteristics of SS, pH, titratable acidity, mass, volume and pulp yield related to ripe fruits, allowing harvesting after 60 DAA.

Yield and Quality of Fertigated Papaya Fruits Submitted to Potassium Doses in Northeast Pará

The objective of this work was to evaluate the effect of potassium doses supplied via fertigation on yield and fruit quality of Solo papaya, cultivar THB. The experiment was installed in August 2018 in the Experimental Station of the Federal Rural University of Amazonia, Municipality of Igarapé-Açu, State of Para, Brazil, and lasted for 13 months. The experiment was conducted in completely randomized design with four replications and treatments applications started in the fifth month after planting. Treatments were four doses of K20 (160, 320, 480 and 640 kg K2O ha-1) that correspond to 50, 100, 150 and 200% of recommended dose based on soil analysis. Potassium was supplied in the form of KNO3, in the irrigation water, associated to the others fertilizers. During the five month harvest period, the papaya yield reached 22.3 t ha-1, fruit number was 67,776 fruit ha-1, fruit weight was about 418.6 g and soluble solid titratable acidity ratio as high as 13.9.