Titratable Acidity Ratio Research Articles

Fruit Quality of Satsuma Mandarin Grown on the Northern Coast of the Gulf of Mexico

This study was conducted to determine fruit quality of Satsuma mandarin Citrus unshiu, Marc. `Owari' grown on the northern coast of the Gulf of Mexico. Soluble solids increased linearly and titratable acidity decreased quadratically during October and November for the four sampling years. There was no significant interaction between sampling date and year. There was a significant year effect for titratable acidity, but not soluble solids or their ratio. A 10:1 soluble solids to titratable acidity ratio was observed on 10 Nov. Variation in fruit weight corresponded with cropload. Fruit weight increased during the sampling period due to an increase in fruit length since there was no change in width. Peel color was yellow-orange by 10 Nov., with many fruit still exhibiting patches of green color. Because of some green color present in the peel, the fruit would have to be degreened for successful marketing in U.S. retail chain stores.

Índices para avaliar qualidade pós-colheita de goiabas em diferentes estádios de maturação

O objetivo deste trabalho foi determinar índices de maturação adequados para avaliar a influência dos estádios de maturação nas transformações físico-químicas após a colheita de goiabas (Psidium guajava cv. Pedro Sato). Frutos colhidos nos estádios de maturação, segundo a cor da casca (1: verde-escura, 2: verde-clara e 3: verde-amarela), foram armazenados a 25±1ºC e 80±5% UR e avaliados quanto às transformações físicas e químicas e percentual de podridão. No momento da colheita, a cor da casca, a firmeza da polpa e a relação sólidos solúveis totais/acidez total titulável apresentaram diferenças significativas entre os três estádios de maturação. Durante o amadurecimento, as transformações físico-químicas foram semelhantes entre os estádios de maturação. O período máximo de viabilidade do fruto para comercialização foi de dois, quatro e seis dias após a colheita, nos estádios 3, 2 e 1, respectivamente. Os teores de sólidos solúveis totais, acidez total titulável e ácido ascórbico apresentaram baixo coeficiente de correlação com as variáveis estudadas. A cor da casca, a firmeza da polpa e a relação sólidos solúveis totais/acidez total titulável foram considerados índices de maturação adequados para a goiaba 'Pedro Sato'.

Performance of `Oroblanco' and `Melogold' Pummelo × Grapefruit Hybrids on Nine Rootstocks on a Calcareous, Poorly Drained Soil

Adjacent but separate trials of `Oroblanco' and `Melogold', both triploid pummelo [Citrus grandis (L.) Osbeck] × grapefruit (Citrus paradisi Macf.) hybrids, were established on nine rootstocks in the Indian River citrus region of Florida in 1993. The trees on the citrandarin rootstock ×639 [Cleopatra mandarin (C. reticulata Blanco) × trifoliate orange (Poncirus trifoliata L.)] were significantly more productive than trees on any other rootstock tested for `Oroblanco' and all rootstocks except Swingle citrumelo (C. paradisi × P. trifoliata) and Cleopatra mandarin for `Melogold'. Cumulative production of `Oroblanco' on ×639, through year 9, was 50% higher than for Swingle or Volkamer lemon [C. limon (L.)], which were the next highest in yield. `Melogold' displayed extremely low yield, with 45% of trees producing fewer than 50 fruit total in the 9 years of this study. Carrizo citrange (C. sinensis Osbeck × P. trifoliata) produced the smallest trees with both scion varieties, reflecting poor adaptation of this rootstock to the calcareous soil at the trial site. As expected, acidity of `Oroblanco' and `Melogold' was much lower than would be observed for grapefruit when fall harvested, with similar total soluble solids (TSS), and much higher TSS: titratable acidity ratio. Some rootstock effects on internal quality were observed.

Effect of bearing position on fruit quality of mandarin types

Differences in juice quality are associated with positional differences in canopy microclimate and exposure of individual fruit to light and temperature. Differences of internal fruit quality between fruit from different sectors of the tree were investigated. The trials were carried out with ‘Mihowase’ Satsuma and ‘Nules’ Clementine trees on Troyer citrange rootstock in Stellenbosch (34°S; 19°E) and ‘Fairchild’ and ‘Temple’ tangor trees on rough lemon rootstock in Citrusdal (32°30'S; 19°E), South Africa. Fruit were harvested from four sectors in each tree, viz. north, south, east and west. Within each sector, fruit were harvested from three sub-sectors, i.e. the top, and the inside and outside bottom sub-sectors. Fruit from each sector were scored for colour, size, juice content, total soluble solids (TSS), titratable acidity (TA) and TSS: TA ratio. (i) Colour: ‘Fairchild’ fruit from all sub-sectors were fully coloured (orange) at harvest. There were no fruit colour differences between the sub-sectors in each sector for each of the other cultivars. The north sector had significantly greener fruit than the south sector for Satsumas, Clementines and ‘Temple’, (ii) Fruit size: For Satsumas, Clementines and ‘Temple’ the top fruit were the largest and inside bottom fruit the smallest, but the opposite occurred for in ‘Fairchild’. (iii) Juice content: The % juice content in all four cultivars was the lowest in top fruit and the highest in inside bottom fruit, (iv) Total soluble solids (TSS): The TSS in all four cultivars was the highest in top fruit and the lowest in inside bottom fruit. The TSS in fruit from the north sector was significantly higher than fruit from the south sector for ‘Fairchild’ and ‘Temple’, with no differences for Satsumas and Clementines, (v) Titratable acidity (TA): For Satsumas and Clementines the inside bottom fruit had the highest TA levels and outside bottom fruit the lowest levels, with no trends for ‘Fairchild’ and ‘Temple’, (vi) TSS:TA ratio: Outside bottom fruit (Satsumas) and top fruit (Clementines, ‘Fairchild’ and ‘Temple’) had the highest TSS:TA ratios and inside bottom fruit the lowest. The north sector in all the cultivars had higher TSS:TA ratios than the south sector. Top and outside bottom fruit had the best quality. This study provides information that can be used to set a standard for sampling fruit for quality determinations, as a guide for spot-picking and harvesting, and in developing pruning strategies.

Harvest Maturity and Storage Affect Quality of `Cripps Pink' (Pink Lady®) Apples

Quality of `Cripps Pink' apples (Malu × domestica) harvested at a starch index of 2 and 4 was evaluated over three crop seasons. Apple quality was evaluated after harvest and after regular atmosphere (RA) and controlled-atmosphere (CA) storage at 1% O2 and 1% CO2, 1% O2 and 3% CO2, and 1% O2 and 5% CO2 (1 year only) at 1 ºC (33 to 34 ºF). Over three seasons, commercially acceptable fruit quality was achieved on either harvest date following both long-term RA and CA storage. Fruit size was not different between apples harvested at a starch index of 2 or 4. Firmness and acids remained at acceptable levels [62 N (14 lb) and ≥0.50%, respectively] in `Cripps Pink' apples regardless of maturity, storage time or storage conditions. Delaying harvest after a starch index of 2 was achieved increased soluble solids concentration (SSC), SSC to TA (titratable acidity) ratio, peel color, malic acid and citric acid concentrations but decreased fructose content. `Cripps Pink' apples responded well to CA storage conditions of 1% O2 with 1% or 3% CO2, but displayed significant firmness loss and greatly increased internal breakdown at 1% O2 and 5% CO2 at 1 ºC.

CARACTERÍSTICAS FÍSICAS E QUÍMICAS DE FRUTOS DE MAMOEIRO DO GRUPO 'SOLO' COMERCIALIZADOS EM 4 ESTABELECIMENTOS DE BRASÍLIA-DF

As características físicas e químicas do mamão do grupo 'Solo' comercializado em 4 estabelecimentos de Brasília-DF, foram analisadas durante o período de setembro de 1997 a agosto de 1998. Foram coletados, mensalmente, 15 frutos em cada estabelecimento para determinar a sua qualidade. Frutos de plantas hermafroditas representaram 88% do total. O peso médio variou de 372,2 a 537,1g, sendo maior em junho. O comprimento e o diâmetro médio oscilaram entre 12,4 a 14,5cm e 7,6 a 8,7cm, respectivamente. O grau de maturação dos frutos coletados, na sua maioria, não estava no ponto de consumo. A firmeza da polpa dos frutos oscilou de 0,56 a 1,04 kg/cm², estando abaixo da firmeza adequada para comercialização. O teor médio de SST variou de 9,9º a 12,5(0) Brix, sendo mais alto em agosto. O pH oscilou entre 5,20 e 5,71 e foi mais alto em agosto e setembro. A acidez titulável, expressa em ácido cítrico, variou de 0,04 a 0,16%, e a relação SST-AT entre 74,7 e 275,7.

AVALIAÇÕES FÍSICO-QUÍMICAS EM FRUTOS DE DIFERENTES GENÓTIPOS DE ACEROLA (MALPIGHIA PUNICIFOLIA L.)

O presente trabalho teve como objetivo avaliar quanto às características químicas e físico-químicas frutos de 12 genótipos de acerola (Malpighia punicifolia L.), em processo de seleção pela Embrapa Mandioca e Fruticultura, visando a identificar aqueles com altos teores de vitamina C e elevada relação Brix/acidez. Os frutos analisados foram colhidos no estágio de maturação "de vez", na safra de setembro a outubro dos anos de 1997 e 1998. Os resultados obtidos para vitamina C variaram de 835 a 1820 mg de ácido ascórbico por 100 g de polpa, para sólidos solúveis totais de 6,0 a 11,6%, para acidez total titulável de 0,69 a 1,65%, para relação Brix/acidez de 4,24 a 11,59 e para pH de 3,08 a 3,57. Dentre os genótipos analisados, o CMF022 e o CMF019 apresentaram os maiores teores de vitamina C e os menores valores para a relação Brix/acidez, enquanto os genótipos CMF015, CMF008 e CMF010 apresentaram a maior relação Brix/acidez, nos dois anos do experimento.

Understanding American and Chinese consumer acceptance of ‘Redglobe’ table grapes

‘In-store’ consumer acceptance tests were performed on a group of 400 American consumers and 250 native Chinese consumers to determine the relationship between ripe soluble solids concentration (SSC) and titratable acidity (TA) on consumer acceptance of ‘Redglobe’ grapes for different ethnic groups. For this, a group of Caucasian, Hispanic and Chinese-American consumers and a group of native Chinese consumers tasted monadically four individual berry half samples at room temperature with SSC ranging from 10 to 20% and TA from 0.30 to 1.80%. Grapes with SSC 16.1% were accepted by 70% of the American consumers and 47% of the Chinese consumers. However, the percentage of consumers that disliked these grapes was the same ( 21) for both ethnic groups. The difference in the percentages of Chinese and American consumers accepting the grapes was due to the ‘neither like nor dislike’ category. Chinese consumers chose the ‘neither like nor dislike’ category in approximately 34% of the cases, while approximately only 7% of the American consumers chose it. Our data confirmed that ‘Redglobe’ consumer acceptance is highly related to SSC:TA ratio but within a given SSC and TA level. In contrast to American consumers, Chinese consumer acceptance was not related to SSC:TA ratio when TA 0.80%. Thus, our work indicates that high TA affects consumer acceptance in relation to SSC:TA ratio depending on ethnic background. © 2002 Elsevier Science B.V. All rights reserved.

The effect of combined deficit irrigation and summer trunk girdling on the internal fruit quality of ‘Marisol’ Clementines

The influence of girdling, deficit irrigation, and a combination of girdling and deficit irrigation on fruit quality of ‘Marisol’ Clementines was investigated over two seasons, 1998 and 1999, at two different sites in South Africa. Girdling increased the total soluble solids (TSS) by 2–10%, however, the effect was not always significant. There were no trends observed for external fruit colour, fruit diameter, juice content (%), titratable acidity (TA) and TSS:TA ratios due to girdling. Deficit irrigation increased the TSS (by 2–17%) and the TA levels (by 9–13%) in both seasons and at both sites, increased the TSS:TA ratio at Citrusdal in 1998 (4–8%), and decreased the TSS:TA ratio (by 7%) in the second season (1999) at both sites due to the increased acidity levels (by 11–13%). Deficit irrigation had no major effects on external fruit colour and juice content in 1999, but decreased fruit diameter (by 10%) at Citrusdal. According to these results, deficit irrigation, summer trunk girdling, or a combination of both, can be used as cultural practices to improve internal fruit quality. The combination of girdling and deficit irrigation increased the TSS more than when the practices are executed on their own.

Location and Rootstock Affect Sheep-nosing in Grapefruit

Field studies were conducted for 2 years, at three sites in the Lower Rio Grande Valley of Texas, to evaluate the effects of location, rootstock, and irrigation on sheepnosing (elongation of the apex) of `Rio Red' grapefruit (Citrus paradisi Macf.). Based on the ratio of equatorial to polar diameter, grapefruit budded on sour orange (Citrus aurantium L.) rootstock grown at Weslaco had a significantly higher percentage of sheepnosed fruits (63%) than did fruit grown at Mission (57%), while the grove at Bayview produced a negligible percentage of sheepnosed fruit (4%). In a second study, `Rio Red' trees grown on `Carrizo' rootstock [C. sinensis (L.) Osbeck × Poncirus trifoliata (L.) Raf.] produced a significantly higher percentage of sheepnosed fruit (59%) than did those on `Swingle' (C. paradisi × P. trifoliata) (48%). In a third experiment, trees irrigated by microjet had a significantly higher percentage of sheepnosed fruit (53%) than did those that were flood-irrigated (43%). Although sheepnosed fruit had significantly greater peel thickness and a lower juice content, fruit quality was better than that of normal fruit because of a higher soluble solids: titratable acidity ratio. In 1999, the significant irrigation and rootstock effects were less than that due to growing location. Effects of location, rootstock and irrigation varied between years. The interaction between factors and years was mainly due to a lack of low amount of sheepnosing in 1998.

596 Location and Rootstock Effects on Sheepnosing in Grapefruit

Two-year field studies at three sites in the Lower Rio Grande Valley of Texas were conducted to evaluate the effects of location, rootstock, and irrigation on sheepnosing of `Rio Red' grapefruit (Citrus paradisi Macf.,) on sour orange (Citrus aurantium L.) rootstock. Based on the equatorial/polar diameter ratio, grapefruit grown in Weslaco had significantly higher percentage of sheepnosed fruits (62.66) than fruit grown in Mission (57.32), while Bayview had a negligible percentage of sheepnosed fruit (4.07). In a second study, `Rio Red' grapefruit grown on Carrizo [C. sinensis (L.) Osbeck × Poncirus trifoliate (L.) Raf.] had significantly higher percentage of sheepnosed fruit (59.46), compared to `Rio Red' grown on Swingle (C. paradisi × P. trifoliata) (47.83). In a third experiment, grapefruit with microjet irrigation had a significantly higher percentage of sheepnosed fruit (53.40), compared to flood irrigation (42.68). Although sheepnosed fruit had significantly greater peel thickness and a lower juice content, fruit quality was better because of higher soluble solids: titratable acidity ratio compared to normal shaped fruits. While significant, the irrigation and rootstock appear have a minor effect on sheepnosing less than growing location.

Efeito do ethephon e da frigoconservação na maturação de pêras cv. Packham's Triumph

Este trabalho, realizado em 1996 na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul, em Eldorado do Sul, RS, e na Embrapa-Centro de Pesquisa Agropecuária de Clima Temperado (CPACT), em Pelotas, RS, objetivou avaliar o efeito do ethephon aplicado em pré-colheita e da frigoconservação na maturação da pêra (Pyrus communis L.) cv. Packham's Triumph. O ethephon foi pulverizado nas concentrações de 0, 12,5, 25, 50 e 100 ppm, e as pêras frigorificadas a -1,0ºC e 92-96% de umidade relativa por 0, 10, 20, 40 e 80 dias. Após os períodos de armazenamento refrigerado, os frutos foram conservados em temperatura ambiente por dois ou oito dias. A firmeza da polpa apresentou uma tendência de diminuição com o aumento das concentrações de ethephon, do período de frigorificação e dos dias à temperatura ambiente. O comportamento da relação sólidos solúveis totais (SST)/acidez titulável (AT) variou mais em função da AT do que dos valores de SST. A relação SST/AT aumentou desde a aplicação dos tratamentos até a colheita. A produção de etileno aumentou com o aumento do período de frigorificação e do número de dias em temperatura ambiente; mas não foi influenciada pela concentração de ethephon.

Qualidade de híbridos de melão amarelo em diferentes densidades de plantio

Objetivou-se avaliar neste trabalho a qualidade de frutos em híbridos de melão amarelo. O experimento foi conduzido na Fazenda Santa Júlia Agro Comercial Exportadora de Frutas Tropicais Ltda, em Mossoró, no período de outubro a dezembro de 1996. O delineamento experimental foi blocos casualizados em esquema fatorial 3 x 4, com quatro repetições, sendo o primeiro fator, os híbridos (Gold Mine, AF 646 e XPH 13096) e o segundo a densidade de plantio (10.000, 20.000, 30.000 e 40.000 plantas/ha). As características avaliadas foram textura, sólidos solúveis totais, acidez total titulável, açúcares totais e relação de formato do fruto. A densidade de plantio teve influência significativa na relação de formato. O híbrido AF 646 apresentou maiores teores de sólidos solúveis totais (10,33%) e açúcares totais (8,45%), o 'Gold Mine' foi melhor na textura (40,50 N) e relação de formato e o 'XPH 13096' apresentou maior acidez total titulável (14,38 mg/100 ml suco). No geral, os três híbridos apresentaram frutos de formato oblongo e à medida que aumentou a densidade de plantio, houve tendência de arredondamento dos mesmos.

172 Changes in Quality and Maturity of Early Season Nectarines (cvs. Aurelio and Early May) during Maturation and Ripening

The objectives of this study were to characterize the quality and maturity changes of nectarine (Prunus persica var. Nectarina) fruit cvs. Aurelio and Early May during maturation and ripening and to identify harvest maturity indices. After fruit set, 250 fruit of similar diameter and tree position were tagged to follow maturation and ripening on the tree. During commercial harvest, 48 fruit were ramdomly harvested every 2 to 3 days. Ethylene evolution rate (EER) at 20 °C, fresh weight, and peel ground and cover color (L*, a*, b*, C* and Hue value) were measured on all 48 fruit. Flesh color, firmness at several fruit points, soluble solids (SS), pH, titratable acidity (TA) and SS: TA ratio were measured only to 24 fruit, and the rest were held for up to 7 days at 20 °C as a ripening period to measure the same parameters mentioned above. Pearson correlation coefficients were determined between variables to explore possible harvest maturity indices. The most significant changes occurred in EER, fruit firmness, and peel ground color (a* and hue value). For `Aurelio' nectarines the highest correlations (P < 0.001) were obtained between logEER-tip firmness (r = -0.69), tip firmness-a* ground color (r = -0.66) and, tip firmness-hue ground color (r = -0.67). No important correlations (r > 0.60) were found for `Early May' nectarines. It was also found that fruit softening varies according to the point of measurement in the fruit depending on the cultivar.

Long-term storage of ‘Olinda’ oranges under chilling and intermittent warming temperatures

Abstract The influence of intermittent warming (IW) during storage, with cycles of 3 weeks at 3°C followed by 2 weeks at 15°C, on the keeping quality of ‘Olinda’ oranges, was investigated over a period of 25 weeks and compared to continuous storage at 3°C (chilling temperature). Intermittent warming delayed the onset of CI by approximately 10 weeks with respect to storage at 3°C and greatly enhanced resistance to CI development. There was very little rotting (6%) after 25 weeks of storage, with negligible differences caused by storage conditions. Soluble solids concentration (SSC), titratable acidity (TA) and maturity, as determined by SSC:TA ratio, were not significantly affected by temperature storage conditions. After 20 weeks acetaldehyde accumulation in the juice was significantly higher in fruit stored at 3°C than in that intermittently warmed, while ethanol levels were higher after 15 weeks. Respiration rates in fruit stored at constant temperature decreased significantly after 5 weeks, increasing slightly over the remaining weeks. Conversely, the respiration rate in fruit under IW was almost the same over the whole storage period. Ethylene concentrations remained very low during storage, with no significant differences due to storage conditions. The degree of fatty acid unsaturation of the lipid fraction from flavedo tissue showed only minimal changes in fruit stored with IW whilst it increased greatly in fruit stored at 3°C.

Potential Maturity Indices and Developmental Aspects of Melting-flesh and Nonmelting-flesh Peach Genotypes for the Fresh Market

Potential maturity indices were determined for two melting-flesh (FL 90-20 and `TropicBeauty') and two nonmelting-flesh (`Oro A'and Fl 86-28C) peach [Prunus persica (L.) Batsch.] genotypes. A range of developmental stages was obtained by conducting two harvests and separating the fruit based on diameter. Fruit in each category were divided into two groups. One group was used to determine potential maturity indices: soluble solids, titratable acidity, soluble solids to titratable acidity ratio, peel and flesh color on the cheeks and blossom end, cheek and blossom-end firmness, ethylene production, and respiration rate. The other group was stored at 0 °C for 1 week and ripened at 20 °C for 2 days to simulate handling conditions and presented to a trained sensory panel, which rated the fruit for three textural aspects (hardness, rubberiness, and juiciness) and six flavor aspects (sweetness, sourness, bitterness, and green, peachy, and overripe character). Principal component (PC) analysis was used to consolidate the results of the descriptive sensory evaluation into a single variable that could be correlated with the objective measurements at harvest. The attributes that best correlated with the first sensory PC of each genotype, and thus are promising maturity indices, were as follows: for FL 90-20, peel hue, peel L, and cheek firmness; for `TropicBeauty', peel L, cheek firmness, and blossom-end firmness; for `Oro A', cheek firmness, blossom-end firmness, and cheek chroma; and for 86-28C, blossom-end firmness, cheek hue, and cheek firmness.

Response of Tarocco Oranges to Picking Date, Postharvest Hot Water Dips, and Chilling Storage Temperature

Tarocco blood oranges (Citrus sinensis Linn. Obsek) were harvested monthly from November to April and dipped in water at 53 °C for 3 min before storage at 3 °C for 10 weeks and 1 additional week at 20 °C, which simulated a marketing period (SMP). Untreated fruit were used as control. No treatment damage was observed in fruit harvested in March. In contrast, hot water dipping caused severe damage to the peel in fruit picked earlier and later in the season. Susceptibility to chilling injury (CI) was greatest in fruit harvested between November and January, less in February, and negligible in March and April. Prestorage hot water dipping effectively alleviated CI in all samples, especially those which showed greater susceptibility. There was little rotting in fruit harvested between November and Januay, while fruit harvested between February and April exhibited a greater susceptibility, which varied with picking date. Hot water dipping gave beneficial effects on decay control of fruit harvested in February and March but was detrimental for fruit harvested in April. Fruit mass loss gradually increased with maturity stage and was seen to be promoted by hot water dips during both cold storage and SMP. The influence of hot water dipping on respiration rate, endogenous ethylene, maturity index (evaluated by °Brix/juice titratable acidity ratio), ethanol concentration in the juice, and electrolyte leakage from the flavedo tissue was nonsignificant. It was concluded that prestorage hot water dipping at 53 °C may be viable in limiting CI and decay control of Tarocco oranges during 10 weeks of cold storage and subsequent SMP when they are harvested at mid-season, January−February, but may be harmful to fruit harvested early or late in the season. Keywords: Citrus; chilling injury; harvest date; heat treatments; storage; rots; fruit quality

Research on Chemical Composition of Some Varieties of European Plums (Prunus domestica) Adapted to the Aegean District of Turkey

The physical characteristics and chemical composition of 11 plum varieties adapted to the Aegean region of Turkey at Ege Agricultural Research Institute, Izmir, were investigated. Variety Giant had the most fruit weight within all the plum varieties and it was followed by Krikon Damson, Tuleu Timpuriu, and Baneasa 3/5. Mean chemical compositions for all varieties were as follows: moisture, 837.4 g kg-1; soluble solids, 155.5 g kg-1; titratable acidity, 15.1 g kg-1; soluble solids to titratable acidity ratio, 12.6; total sugar, 96.5 g kg-1; total sugar to acidity ratio, 7.59; reducing sugar, 51.9 g kg-1; sucrose, 42.4 g kg-1; ascorbic acid, 157.9 mg kg-1; protein, 7.5 g kg-1; ash, 5.5 g kg-1; sodium 161.53 mg kg-1; potassium, 2228.12 mg kg-1; calcium, 25.47 mg kg-1; iron, 4.70 mg kg-1; pH 3.46. Imperial Epineuse was the most suitable variety for drying. Grand Prize had the highest ascorbic acid content. Keywords: European plums; Prunus domestica; Chemical composition; Physical characteristics

Nitrogen Fertilization Affects Quality of Peach Puree

Clingstone peach [Prunus persica (L.) Batsch cv. Allgold] trees were fertilized once with 45 or 90 kg N/ha at budbreak or twice with 22.5 or 45 kg N/ha at budbreak and after harvest. A nonfertilized control was included. Fruits from all treatments were made into puree, and objective and subjective qualities were evaluated. Puree from the N treatments and the control did not show significant differences in Color Difference Meter (CDM) `L' and hue angle, pH, titratable acidity (TA), soluble solids concentration (SSC), SSC: TA ratio, viscosity, ascorbic acid, Ca, K, phenolic and nitrates concentration. Puree from the control and 22.5 kg N/ha applied twice had significantly lower CDM `a', `b', and chroma values than from the other treatments. The split applications of N significantly reduced levels of Ca and ascorbic acid. N rate and number of applications interacted for `a' and K. When N was applied twice at 22.5 kg·ha-1, `a' and K decreased, but this response was absent when N was applied twice at 45 kg·ha-1. Puree from the nonfertilized control was rated lower by panelists for sensory quality than that from the fertilized trees. Peach puree from trees fertilized once with 45 kg N/ha at budbreak had the best overall sensory quality.

Quality Parameters in Four Melon Hybrids Stored at Different Temperatures

Melon fruit (Cucumis melo L.) from Chando, Concorde, Explorer, and Durango hybrids, collected from a Sante Ines farmer from Rio Tocuyo, were stored at 5, 10, and 18°C and room temperature for 7, 14, and 21 days with the objective of getting the response of melon hybrids in relation to quality characteristics. The soluble solids content and dry matter were not significant in the studied hybrids, titratable acidity was higher at 5°C, Chando had the highest values. Explorer had the highest pH values and soluble solids: titratable acid ratio at room temperature. Reducing and total sugars had the lowest values at 18°C and room temperature, Chando had the highest values. Concorde had the highest values for fresh weight loss at room temperature during 21 days of storage.