首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
The effects of harvest date and cold storage period on ethylene production, fruit firmness and quality of ‘Cripps Pink’ apple were investigated. Fruit were harvested from Perth Hills and Donnybrook (Western Australia) at commercial maturity (CM), 2, 4 and 6 weeks after CM prior to 0, 45, 90 and 135 days cold storage in 2003 and 2004. Delayed harvest significantly increased ethylene production, CIE values a* and C* at both locations in 2 years. Delayed harvest and extended cold storage period increased the internal ethylene production and reduced fruit firmness, soluble solids concentration: titratable acidity (SSC:TA) ratio and reduced CIE values L*, b*, h° during both years and locations. Fruit harvested 2 weeks after CM can be cold‐stored for 90 days with acceptable fruit quality. If the fruit is intended to be sold fresh immediately in local markets, the harvest can be delayed up to 6 weeks after CM to harness substantially improved fruit colour with acceptable fruit quality.  相似文献   

2.
3.
The changes in the quality parameters of Spanish pomegranate fruit (cultivar Mollar) during ripening and during 7 weeks of cold storage at 5°C and 90–95% relative humidity were studied. The fruit and seed weights, as well as the surface colour increased with ripening. Total soluble solids (TSS), pH and titratable acidity (TA) did not show significant differences during the weeks studied (from the 26th to 32nd weeks after flowering), but the seeds' colour (Lab values) and juice colour (absorbance at 510 nm) showed an increase during this period with a maximum during the last 2 weeks. These results indicate that pomegranates should be harvested during the 31st to the 32nd after flowering, in order to get the best pigmentation without a decrease in other quality parameters. The anthocyanin profile changed during the different maturity stages, since the diglucoside derivatives were the prevailing pigments during the early ripening stages, whereas the monoglucoside derivatives were the main pigments in the latter stages. After cold storage of pomegranates harvested at two maturity stages, no differences in TSS, pH, TA and skin colour were observed. In addition, seeds' and juice colour did not decrease during storage. Hence, this study supports the theory that pomegranate is a nonclimacteric fruit and that pomegranates can be stored for at least 45 days without deterioration in the fruit quality.  相似文献   

4.
ABSTRACT:  The effect of gaseous ozone exposure on the quality of persimmon picked at 2 different harvest dates was evaluated. Fruit from both harvests were continuously exposed to 0.15 ppm (vol/vol) of ozone for 30 d at 15 °C, 90% relative humidity (RH). Then, fruit were submitted to astringency removal treatment (24 h at 20 °C, 98% CO2) and stored for 7 d at 20 °C (90% RH) in order to simulate shelf-life period. The most important disorder was flesh softening, which took place when fruit were transferred from 15 °C to shelf-life conditions. In the 2nd harvest, where the fruit were harvested with lower firmness, ozone maintained firmness over commercial limits even after 30 d at 15 °C plus shelf-life. Ozone-treated fruit showed the highest values of weight loss, coinciding with the maximum electrolyte leakage (EL) percentage. Ozone did not affect color index (CI), ethanol, total soluble solids (TSS), or pH. Unremarkable differences in acetaldehyde were observed between fruit submitted to ozone treatment and control fruit. No phytotoxic injuries in tissues were observed in ozone-treated fruit.  相似文献   

5.
The effects of various fruit maturities and different light intensities on berry fruit quality, antioxidant capacity and phytonutrient levels in red raspberries (Rubus ideaus L.) were determined. At harvest, immature berries contained significantly lower levels of sugars and acids than ripe berries. When berries were harvested at 5% or 20% maturity, they never developed the levels of soluble solids content (SSC) and titratable acid (TA) values observed in ripe berries at harvest. However, fruit harvested at 50% or more advanced maturity had the capacity of attaining comparable levels of SSC, TA and sugars as those harvested at 100% maturity. When 5% and 20% berries were stored under light, higher level of SSC and lower levels of TA values were observed than those kept in the dark. However, light condition showed little effect in 50% and 80% maturity fruit after 4 days at 24/16 °C (day/night). Ripe raspberries (100%) had stronger antioxidant activities and higher total anthocyanin content when compared with the pink stage (50% maturity). Fruit harvested at greener stages (5% and 20%) also consistently showed higher antioxidant activities and total phenolics than those harvested at 50%. Cyanindin-based anthocyanins increased during postharvest period. On the other hand, other polyphenols such as ellagic acid, quercetin 3-glucoside, quercetin derivative, and kaempferol 3-glucuronide were initially present at high levels but decreased drastically during storage. Red raspberries harvested at different developmental stages continued their development during storage even under the dark conditions. The antioxidant activity of red raspberries was directly related to the total amount of phenolics and flavonoids. Results of this study indicate that red raspberries harvested at 50% or more advanced maturity could develop comparable quality and antioxidant levels as those harvested at full maturity.  相似文献   

6.
While nitrogen (N) and potassium (K) fertilizers are commonly used in tomato fields for increasing plant growth and productivity, concepts regarding the interactive effects of these elements on tomato fruit quality during storage are ambiguous. The interactive effects of potassium (0, 250 and 500 mg kg soil??1) and nitrogen (0, 150 and 300 mg kg soil??1) fertilizers were tested on tomato fruit size at harvest, and their quality was evaluated after 30 days of storage at 4 °C. Fruit mass, firmness, taste-related parameters, inorganic nutrients, bioactive compounds, and antioxidative capacity of the fruits were investigated after the storage period. Application of 250–500 mg K in combination with 150 mg N per kg soil improved fruit mass at harvest and reduced loss of mass during storage. By increasing the soil’s K supply, the fruits exhibited significant increases in their amount of potassium, TSS and TA contents, antioxidative capacity, concentrations of lycopene, phenolics and ascorbic acid. Nonetheless, increasing the soil’s K concentration reduced Ca concentration and firmness of the fruits. By increasing the N concentration in the soil, a trend of decline was observed in the fruits’ TSS, soluble phenolics, lycopene and ascorbic acid contents. However, higher amounts of N and TA contents were detected in fruits treated with 300 mg N kg soil??1. N treatments did not affect the antioxidative capacity of the fruits. Accordingly, application of 250 mg K?+?150 mg N kg soil??1 was suggested as the optimum treatment that could yield tomato fruits with high quality and that would also have improved storage capability.  相似文献   

7.
Peach and nectarine trees were foliar sprayed with a formulation containing Ca2+, Mg2+ and Ti4+. Parameters related to fruit quality were evaluated at harvest, after 7–28 days of cold storage and after subsequent ripening for 4 days at 20 °C (shelf life). At harvest, treated fruits from both cultivars had higher weight and pulp firmness than control fruits, while no effect was observed for either colour, total soluble solid content (TSS) and titratable acidity (TA) or the time required to ripen on the tree. During cold storage, lower levels of weight loss, colour evolution, TSS/TA ratio and ethylene production and higher pulp firmness were found in treated peaches and nectarines compared with control fruits. Also, the storability of treated fruits was extended for up to 14 days more than that of control fruits. During ripening at 20 °C after different periods of cold storage, parameters related to ripening evolved faster in control than in treated fruits. Also, the occurrence of the climacteric peak of ethylene production was delayed and its intensity was lower in treated peaches and nectarines than in controls. Copyright © 2004 Society of Chemical Industry  相似文献   

8.
以龙滩珍珠李为试材,分5个采收期采收果实,探讨不同采收成熟度对龙滩珍珠李果实品质特性的影响。结果表明:随着采收成熟度增加,龙滩珍珠李果实好果率、含水量、出汁率、果皮L*和b*值、脆度和多汁性评分、可滴定酸(titratable acidity,TA)、硬度、咀嚼性、弹性和内聚性均不断下降,整个采收期分别下降了66.67%、4.52%、11.62%、12.28%、62.10%、36.86%、15.86%、23.94%、75.68%、79.77%、15.12%和8.33%;果皮a*值、果肉a*和b*值、外观色泽和甜味评分、可溶性固形物(total soluble solid,TSS)、可溶性糖含量(soluble sugar content,SSC)、pH、固酸比、糖酸比均不断上升,整个采收期分别上升了56.32%、725.39%、31.54%、108.51%、85.80%、41.70%、83.87%、4.87%、85.31%和143.68%;单果质量、酸味评分、感官总分、Vc含量先升高后下降,分别在第Ⅳ、Ⅲ、Ⅲ、Ⅱ采收成熟度时最高,分别为18.25 g、16.13分和89.20分、6.25 mg/100 g。该研究结果可为龙滩珍珠李果实不同的生产目的选择适合的采收成熟度提供参考依据。  相似文献   

9.
Mature green “Baxi” banana (Musa spp. AAA Group, Cavendish) fruits were harvested at 60% and 80% maturity stages. In order to evaluate the effects of harvesting at different maturity stages on storage quality and changes in sucrose-metabolizing enzymes, fruit firmness, disease index, contents of starch, and total soluble sugars were determined, and enzyme activities associated with sucrose metabolism was investigated under natural and accelerated (treated with ethylene) ripening conditions. In fruit treated with ethylene, changes in flesh firmness, total sugar content, starch content, disease index, and activity of sucrose phosphate synthase (SPS), sucrose synthase (SS), acid invertase (AI), and neutral invertase (NI) were accelerated dramatically compared with untreated fruit with both 60% and 80% maturity. When fruit ripened under natural conditions, the changes in firmness, disease index, starch content, total sugar content, SPS activity, SS, AI, and NI activity in fruit with 80% maturity were significantly faster than those in fruit with 60% maturity. On the contrary, when fruit ripened under accelerated conditions, no significant differences in firmness, sugar, starch, disease index, SPS, SS, AI, and NI were observed between fruit harvested at 60% or 80% maturity. It is suggested that storage quality and sucrose-metabolizing enzymes of banana fruit stored under natural conditions are related to harvest maturity stage; storage quality of fruit with lower harvest maturity is better than fruit with higher maturity. However, when fruit ripening is accelerated by ethylene, the harvest maturity stage has no influence on storage quality and changes in sucrose-metabolizing enzymes.  相似文献   

10.
11.
A study was conducted to determine firmness of eight mango hybrids obtained from the crosses between Amrapali and Sensation and correlate it with TSS and peel thickness. The firmness was determined at top, middle and bottom positions of the fruit using TA + Di Texture Analyzer. The peel firmness at middle position of the hybrids varied from about 20 to 33 N on harvest day, which decreased to 5–12 N with increase in storage period. On 7th day of storage, the peel firmness became almost equal from top to bottom positions indicating the even ripening of fruit. Pulp firmness was found to vary from about 5 to 20 N of freshly harvested fruit, which reduced to 0.3–3.5 N during storage. Peel firmness of 5 N and pulp firmness of 0.3 N was found as threshold points below which the fruit may not be acceptable for consumption.  相似文献   

12.
Mango fruit has a relatively short storage life of about 2 to 3 weeks at 13C. In order to prolong the storage life of ‘Haden’ mangoes, fruit were coated with 3 concentrations (8,16 and 24 g.L?1) of the edible coating film “Semperfresh” and then stored at 13C and 85% RH. Fruit were then evaluated every 4 days for up to 32 days for total soluble solids (TSS), titratable acidity (TA), pH, firmness, weight loss, color of the skin, and ascorbic acid content. All 3 concentrations applied to the fruit affected fruit ripening. TA, firmness, and green color were higher in coated fruit, and weight loss, SST, and pH were lower compared with the noncoated fruit. “Semperfresh” had no effect on decay development. Ascorbic acid decreased in all stored fruit, but this decrease was slower in coated fruit, and there were no significant differences between the different “Semperfresh” concentrations.  相似文献   

13.
In Israel, fresh dates are normally harvested unripe and stored in a controlled environment until marketed. Proper ripening depends on maturity at harvest time. Sugar and water contents of the dates are considered important maturity attributes. Decision‐making on the harvesting schedule for each section in a plantation of fresh dates (variety Hayani) is one of the major problems for the growers. In order to estimate the optimum harvest time, conventional laboratory methods have been used to assess the maturity of samples of dates; methods which by nature are destructive, manual and time consuming. A semi‐automatic system for maturity determination of fresh dates has been developed, tested and operated. It combines a near infrared (NIR) spectrometer with a step‐wise cell conveyor, both of which are controlled by a PC. The NIR models were based on measuring the water and total soluble solids (TSS) contents. The calibration models and the prediction results had a standard error of prediction (SEP) of 1% for TSS and water contents. The correlation coefficient R between TSS and water contents as predicted by NIR models and as measured in routine laboratory destructive tests was 0.9. The system was capable of testing 100 dates in 3 min. © 1999 Society of Chemical Industry  相似文献   

14.
PCA综合分析采收成熟度对金沙柚贮藏品质的影响   总被引:1,自引:0,他引:1  
为选择适宜金沙柚长期贮藏的采收成熟度,本试验以盛花后195、206和216 d(成熟度Ⅰ、Ⅱ和Ⅲ)采收的果实为对象,检测了常温贮藏180 d内果实感官品质以及抗氧化相关指标,并通过主成分分析法(PCA)综合评价不同采收成熟度对金沙柚贮藏品质的影响。感官品质检测结果表明:成熟度Ⅰ和Ⅲ的腐烂率低于成熟度Ⅱ;成熟度Ⅱ和Ⅲ失重率低于成熟度Ⅰ。成熟度Ⅱ CCI值高于成熟度Ⅰ和Ⅲ,成熟度Ⅲ亮度(L*)最高。成熟度Ⅰ可溶性糖、VC含量和固酸比高于成熟度Ⅱ和Ⅲ,TA含量反之;成熟度Ⅱ的TSS和VC高于成熟度Ⅲ。三者出汁率无明显差异。抗氧化性指标检测表明:成熟度Ⅰ和Ⅱ的总酚含量在贮藏180 d内显著高于成熟度Ⅲ,分别于180和150 d达到最大值(197.68和201.08 μg/g)。成熟度Ⅰ和Ⅱ总黄酮含量高于Ⅲ。成熟度Ⅱ和Ⅲ的DPPH清除率前30 d高于成熟度Ⅰ。三个成熟度FRAR还原力维持OD值0.35左右,无明显差异。PCA分析发现:0~30 d成熟度Ⅱ综合得分最高,在60~180 d成熟度Ⅰ综合得分最高并在90 d达最高值0.59分,成熟度Ⅲ整体得分最低。说明盛花后206 d采收的金沙柚贮藏30 d上市最好,最长贮藏不宜超过120 d;盛花后195 d采收的金沙柚贮藏90 d上市最好,最长贮藏不宜超过150 d;盛花后216 d采收的金沙柚不适合贮藏。  相似文献   

15.
The effects of storage and post-harvest maturation on the physicochemical characteristics and volatile constituents of Bergeron apricot were investigated during the 2007 season over two experiments. Fruits, harvested at two distinct stages of maturity, in two different experimental orchards, were stored in cold chambers at +1 °C for up to 3 weeks and then subjected to a post-harvest maturation in ripening chambers at 20 °C and 60–70% RH up to 7 days. Firmness, soluble solids (SS), titratable acidity (TA), and the levels of the main volatiles were determined. Physicochemical changes included a significant decrease of firmness during both storage and post-harvest maturation whereas the levels of SS and TA were found to be very similar. The results also indicated that, whatever their initial stage of maturity at harvest, the rates of softening of apricots during storage and/or post-harvest maturation were very comparable. During post-harvest maturation, the levels of C6-compounds decreased drastically whereas, at the same time, those of esters, lactones and terpenic compounds greatly increased. During storage at 1 °C, a decrease of C6-compounds was also observed. As regards other compounds, there were some statistically different results between samples but the changes observed for lactones, esters and terpenic compounds were relatively small in comparison to those observed during post-harvest maturation at 20 °C. The results also showed that, at the end, qualitative and quantitative differences can be observed in the “ready-to-eat” apricots according to their initial stage of maturity at harvest. On average, apricots harvested at the most advanced stage of maturity have, on average, the highest levels of soluble solids and the highest levels of volatile compounds of interest.  相似文献   

16.
‘Rojo Brillante’ persimmons were harvested in 2 different dates, early and late, and then submitted to 1‐methylcyclopropene (1‐MCP) treatment (500 nL/L) before stored at 1 or 15 °C up to 50 or 30 d, respectively. The influence of harvest date, 1‐MCP treatment, orchard, storage time, and temperature on firmness loss and color evolution during storage of ‘Rojo Brillante’ persimmon was studied. Statistical models that allowed the prediction of these 2 quality parameters during the storage, as well as the modeling of the behavior of both of them, were also evaluated. The softening, as a consequence of chilling sensitiveness when stored at 1 °C, was more accentuated in the early harvested fruit. In storage at 15 °C, also, the firmness loss was faster in fruit harvested earlier. 1‐MCP treatment drastically reduced chilling injury (CI) symptoms at 1 °C and retarded firmness loss at 15 °C, both of these effects being dependent on harvest date. The model presented to study the firmness and color relationship offers an important tool to predict firmness from fruit color measurements.  相似文献   

17.
研究温度、乙烯对京白梨果实后熟进程及品质的影响。测定果实乙烯释放量、呼吸强度、果实硬度、可溶性固形物含量、pH值、果皮颜色ΔE 值和h 值、失重率、病果率等指标,并进行感官评价。结果表明:温度和乙烯直接影响果实的后熟进程和后熟品质;后熟过程中果实硬度与后熟时间呈极显著线性负相关(P< 0.01),温度过高或过低均导致果皮转色和果实硬度后熟不一致,适度的低温(14℃)延迟了果实乙烯峰值的启动时间,高温(28℃)抑制乙烯的生成和果实的软化,温度越高,失重率和烂果率越高;外源乙烯有助于果实乙烯的生成和呼吸强度的增加,乙烯加快了果实的后熟进程,并且后熟更均匀一致,且品质最佳。研究表明:京白梨后熟的适宜温度范围17~23℃,最佳温度20℃,最佳乙烯催熟用量为100μL/L。  相似文献   

18.
The effect of fruit ripening on the quality of the oil extracted and on the changes in the amount of phenolic compounds was determined in two olive varieties (Olea europaea, cvs. Arbequina and Picual) in two crop seasons, characterized by showing the same mean temperature and different rainfalls. Maturation level was evaluated using six methods: Harvest date, ripening index (RI), fruit skin colour, fruit firmness, and amount of chlorophylls and carotenoids in the oil. Oil quality, evaluated using the parameters established to determine the quality level of virgin olive oils (acidity, K232, K270, peroxide index, and panel test), was not affected by fruit ripening or by the increase in rainfall of the season. However, the changes in oil stability and phenolic compounds in the oils extracted during fruit ripening strongly differed according to the variety, the maturity level of the fruit and the crop season tested. Fruit skin colour and firmness allowed a better discrimination at the initial maturity stages than the other methods tested.  相似文献   

19.
The effect of different irrigation strategies on the fruit quality at harvest and during storage at 1 °C of 'Búlida' apricots (Prunus armeniaca L.) was studied. Irrigation treatments consisted of a control irrigated at 100% of crop evapotranspiration (ETc) throughout the season, and two deficit irrigation treatments consisting of continuous irrigation at 50% of control, and regulated deficit irrigation (RDI) at 100% of ETc during the critical periods (second rapid fruit growth and early post‐harvest) and at 25% during the rest of the season. Fruits at harvest from both deficit irrigation treatments showed higher values of total soluble solids (TSS), titratable acidity and hue angle (h°) than control fruits, whereas their diameter, fresh weight, firmness and maturity index values were similar to those in the control. During the first 10 days of the 30‐day chilling storage period, higher TSS and h° values were found in deficit irrigated fruits, whilst the other parameters were similar for all treatments. Weight loss and fungal attacks (mainly Rhizopus sp. and Monilinia sp.) during a subsequent retail sale period of 4 days at 13 °C were the lowest in RDI. Deficit irrigation was demonstrated to be commercially advantageous for keeping fruit quality, saving considerable amounts of water. Copyright © 2007 Society of Chemical Industry  相似文献   

20.
Postharvest performance of organic and conventional ‘Hayward’ kiwifruits grown on the same farm in Marysville, California, and harvested at the same maturity stage were compared in this study. Quality parameters monitored included morphological (shape index) and physical (peel characteristics) attributes of the initial samples. Maturity indices (CO2 and C2H4 production, firmness, color, soluble solids content and acidity) and content of compounds associated with flavor and nutritional quality (minerals, sugars and organic acids, ascorbic acid, total phenolics, and antioxidant activity) were determined at 0, 35, 72, 90 and 120 days of storage at 0°C, and after 1 week of shelf‐life simulation at 20°C, after each storage duration. Organically and conventionally grown kiwifruits had similar soluble solids content at harvest, but conventional kiwifruits had a higher firmness and L* value, and a lower hue angle and chromaticity, resulting in a lighter green color when compared with the organic kiwifruits. These differences were maintained for all the storage durations, with the soluble solids content increasing more in conventionally grown kiwifruits. The two production systems resulted in different morphological attributes since organic kiwifruits exhibited a larger total and columella area, smaller flesh area, more spherical shape, and thicker skin compared to conventional kiwifruits. All the main mineral constituents were more concentrated in organic kiwifruits, which also had higher levels of ascorbic acid and total phenol content, resulting in a higher antioxidant activity. Sugars and organic acids composition was not affected by the production system. Copyright © 2007 Society of Chemical Industry  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号