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1.
One distinguishing conclusion found in most reviews of research studies comparing organically and conventionally grown produce is that variables shared alike by organic and conventional produce during production, harvest, and postharvest handling and storage were not applied. As a result, accurate and meaningful conclusions comparing the nutritional quality of organic and conventional produce are difficult to ascertain. Pairing common production variables such as the physical, biological, and chemical/nutritional attributes of soils, the irrigation sources and amounts, crop varieties, crop maturities and harvest dates, pre- and postharvest processing, handling, and/or storage methods, individually and collectively, provide greater clarity as to how inputs unique to organic and conventional systems affect produce quality. Variables to be paired during production, harvest, and postharvest handling and storage studies comparing organic and conventional produce are discussed along with findings indicating that organic crops often have higher dry matter, ascorbic acid, phenolic, and sugar and lower moisture, nitrate, and protein contents and yields than conventionally grown crops. Recent studies of nutritional quality in organic versus conventional produce also indicate that soil nitrogen delivery rates strongly affect nutritional quality. Nitrogen profiling is a promising new approach to improving the nutritional quality of both organic and conventional produce.  相似文献   

2.
The present study was carried out to determine the influence of wick and drip substrate hydroponic systems and different ratios of nitrogen (N) and potassium (K) in the nutrient solution on fruit yield and quality (titratable acidity, total soluble solids, ascorbic acid, total soluble sugars, firmness, lycopene, carotenoids) in tomato. Summer and winter tomato crop was raised under two substrate hydroponic systems. Four nutrient solutions (N:K ratios in four combinations) were tested in both the growing seasons at vegetative and reproductive stages of plant development. Among the different nutrient solutions, the solution containing N and K in the ratio of 1.4:3 at vegetative and 1.7:3.5 at reproductive stage increased the total fruit yield and quality of tomato irrespective of hydroponic system or season. Among the hydroponic systems, wick system produced higher fruit yield and better quality in terms of firmness, ascorbic acid, and total soluble sugars in winter crop.  相似文献   

3.
Assessment of genetic variability in the available germplasm is the prerequisite for development of improved genotypes through planned breeding programmes. In view of this, 39 “hatkora” (Citrus macroptera Mont.) genotypes collected from different locations of Mizoram, India were evaluated for physico-chemical characteristics during 2013–2015. The study reveals that there was significant variation among the collections in these particular traits. Individual fruit weight ranged from 277.78 to 617.69 g; fruit diameter 9.32–12.52 cm; fruit length 7.74–10.19 cm, fruit volume 238.33–583.33 cc; pulp weight 153.75–320.94 g; pulp:peel ratio 1.50–3.24 and seed number 9.33–23.6. Similarly, the chemical parameters also varied significantly among different germplasms. The juice content varied from 13.45 to 32.53 %, ascorbic acid 34.81–73.64 mg/100 mL, TSS 6.15–9.10 %, acidity 5.03–8.75 %, total sugars 5.16–7.97 % and sugar:acid ratio 0.75–1.52. From the analysis of genetic parameters, it could be concluded that characters like fruit weight, fruit length, fruit diameter, fruit volume, pulp weight, pulp–peel ratio, juice, Total soluble solids (TSS), acidity, ascorbic acid, total sugars, and sugar–acid ratio could be used as selection criteria for development of effective and productive plant types in “hatkora”. Wide range of variation in physico-chemical parameters of “hatkora” fruits indicated the great scope of individual plant selection based on these characters for future genetic improvement programme.  相似文献   

4.
The development and ripening process of sweet cherry (Prunus avium L. cv. 4-70) on the tree was evaluated. For this purpose, 14 different stages were selected in accordance with homogeneous size and color. Some parameters related to fruit quality, such as color, texture, sugars, organic acids, total antioxidant activity, total phenolic compounds, anthocyanins, and ascorbic acid were analyzed. The results revealed that in sweet cherry, the changes in skin color, glucose and fructose accumulation, and softening process are initiated at early developmental stages, coinciding with the fast increase in fruit size. Also, the decrease in color parameter a was correlated with the greatest accumulation of total anthocyanins. Ascorbic acid, total antioxidant activity (TAA), and total phenolic compounds decreased during the early stages of sweet cherry development but exponentially increased from stage 8, which coincided with the anthocyanin accumulation and fruit darkening. TAA showed positive correlations (r(2) = 0.99) with both ascorbic acid and total phenolic compounds and also with the anthocyanin concentration from stage 8. Taking into account the reduced shelf life of sweet cherry and to ensure that these fruits reach consumers with the maximum organoleptic, nutritional, and functional properties, it is advisable to harvest sweet cherries at stage 12 of ripening.  相似文献   

5.
A study was conducted to investigate the change in quality attributes of red pepper (paprika) (Capsicum annuum L. var. Km-622) as a function of ripening and some technological factors. Of quality attributes, carotenoids and bioantioxidants (ascorbic acid and tocopherols) have been studied. It was found that the dynamics of fruit ripening with regard to carotenoids and bioantioxidants was influenced to a considerable extent by weather conditions of the production season. A rainy and cool season yielded fruits with more beta-carotene but less diesters of red xanthophylls as compared to those produced in a relatively dry and warm season. The ripening stage at harvest was found to affect the quality of paprika. Harvest at unripe stages (color break or faint red) resulted in a high accumulation of dehydroascorbic acid in the overripe fruits, whereas de novo biosynthesis of carotenoids and tocopherols was partially retarded. Application of pre-drying centrifugation resulted in a marked loss of ascorbic acid, and as a consequence, carotenoid stability was impaired during the storage of ground paprika. Sugar caramelization caused dry pods and ground paprika to retain more pigments and tocopherol as compared to those from control or centrifuged red pepper samples. During the storage of ground paprika, color stability was improved by grinding the seeds with the pericarp.  相似文献   

6.
Fruit ripening is a complex phenomenon that makes berries attractive and also determines their nutritional value. Autumn olive ( Elaeagnus umbellata Thunb.) fruit is a rich source of many human health-related nutrients. The changes in pericarp color are initiated at early developmental stages, coinciding with the fast increase in fruit size. Fruit quality traits with special emphasis on soluble sugars, organic acids, lycopene, and total protein contents were assayed during the fruit ripening. In the fully ripe fruit, glucose and fructose were the principal sugars, malic acid was the most abundant organic acid, and lycopene concentration was extremely high. A proteomic analysis was used to identify up-accumulated proteins induced by the ripening. Among 63 up-accumulated protein spots, 43 were successfully identified by MALDI-TOF/TOF-MS. All 43 proteins were novel for autumn olive, and 8 were first reported in the fruit. Twenty-one proteins of known function were involved in sugar metabolism, citric acid cycle, isoprenoid metabolism, fatty acid synthesis, and protein hydrolysis. The possible roles of these 21 accumulated proteins in autumn olive fruit quality are discussed.  相似文献   

7.
The effects of foliar application of boron (B) in the form of boric acid on vegetative and reproductive growth, yield and fruit quality of ‘Kinnow’ mandarin (Citrus reticulate Blanco.) were investigated. Kinnow mandarin was sprayed with different concentrations of boric acid viz. (0.1%, 0.2%, 0.3% and 0.4%) at fruit set stage. Leaf nitrogen (N), phosphorus (P), potassium (K), B, and zinc (Zn) along with flush length, tree height, tree spread and tree trunk diameter increased, while leaf length and leaf age showed non-significant results after foliar B application. Yield of the ‘Kinnow’ mandarin was significantly affected by foliar application of B and a significant increase in fruit weight at harvest was also observed. Soluble solid concentration (SSC): titratable acidity (TA) ratio, ascorbic acid, total sugars, total phenolic content (TPC) and total antioxidants significantly affected, while pH of juice, SSC, TA, reducing sugars and non-reducing sugars showed non- significant results.  相似文献   

8.
Concentrations of grapefruit (cv. 'Rio Red'; Citrus paradisi Macf.) bioactives grown under organic and conventional production systems were evaluated after storage at various temperatures. The first experiment was conducted in November 2008 and the second experiment was conducted in February 2011 using commercial production, processing, and packing procedures. The harvested grapefruits were stored at 23 °C (room temperature) or 9 °C for 4 weeks and analyzed for vitamin C, limonoids, and carotenoids at the end of each week using HPLC. Vitamin C levels were higher in organically grown grapefruits (41.8 mg/100 g) compared to conventionally grown grapefruits (39.2 mg/100 g) at 0 days after harvest in the first experiment. However, production system did not significantly affect vitamin C levels in the second experiment. During storage at room temperature, vitamin C degradation losses ranged from 0.5 to 7% for organically produced grapefruits and from 3 to 18% for conventional grapefruits in both experiments. In the first experiment at harvest, organically produced grapefruits had 77% higher (p ≤ 0.05) nomilin than conventionally produced grapefruits, whereas grapefruits grown under the conventional production system had 2-fold higher lycopene levels compared to organic grapefruits. In the second experiment, both β-carotene and lycopene levels were significantly (p ≤ 0.05) higher in conventionally produced grapefruits than in organic grapefruits. Overall, conventional production significantly increased grapefruit carotenoid levels in both experiments. In general, storage temperature (room temperature and 9 °C) had minimal effects on vitamin C degradation but significant effects on the degradation of carotenoids in the first experiment.  相似文献   

9.
Even though several types of phosphorus fertilizers are used in crop production, the influence of phosphorus on produce quality is not well understood. Several quality attributes of tomato juice were analyzed in relation to phosphorus supplementation during a three-year field study (2000-2002). In addition to the recommended phosphorus fertilization, phosphorus supplementations, either through soil (low and high) or through foliar spray (hydrophos, seniphos), were tested. In general, soil and foliar phosphorus supplementation did not provide a statistically significant increase in yield. Tomato juice was evaluated for various quality characteristics including pH, titratable acidity, precipitate weight ratio, total solids, serum viscosity, Brookfield viscosity, color, lycopene levels, vitamin C, and flavor volatiles. Changes observed in several quality parameters were marginal, statistically insignificant and influenced by the season. Therefore, it appears that phosphorus supplementation may not significantly affect the processing quality parameters in tomato fruits.  相似文献   

10.
A fast, one-step gas chromatographic method was developed to analyze trimethylsilyl (TMS) derivatives of sugars, fruit acids, and ascorbic acid in sea buckthorn (Hippoha? rhamnoides L.) berries. The method was applied to berry press juice of sea buckthorn of different origins grown in Finland during the 2003 and 2004 seasons. The method gave reliable results for D-fructose, D-glucose, ethyl-D-glucose, and malic, quinic, and ascorbic acids, which are the major sugars and acids in sea buckthorn juice. For the first time in sea buckthorn and evidently in any berry, the presence of ethyl beta-D-glucopyranoside is reported. The structure of ethyl glucose was verified by high-performance liquid chromatography (HPLC), gas chromatography (GC), MS, and NMR analyses of both the isolated and the synthesized compounds. In the GC method, vitamin C was analyzed as ascorbic acid only, and dehydroascorbic acid was thus not taken into account.  相似文献   

11.
The columnar cactus Cereus peruvianus (L.) Miller, Cactaceae (koubo), is grown commercially in Israel. The unripe fruits are green, and the color changes to violet and then to red when the fruit is fully ripe. The content of soluble sugars was found to increase 5-fold during ripening. Glucose and fructose were the main sugars accumulated in the fruit pulp, and each increased from 0.5 to 5.5 g/100 g fresh weight during ripening. The polysaccharides content decreased during ripening from 1.4 to 0.4 g/100 g fresh weight. The titratable acidity decreased and the pH increased during ripening. The major organic acid found in the fruit was malic acid, which decreased from 0.75 g/100 g fresh weight at the mature green stage to 0.355 g/100 g fresh weight in ripe fruits. Citric, succinic, and oxalic acids were found in concentrations lower than 0.07 g/100 g fresh weight. Prominent accumulation of aroma volatiles occurred toward the end of the ripening process. The main volatile found in the ripe fruit was linalool, reaching concentrations of 1.5-3.5 microg/g fresh weight.  相似文献   

12.
Color defines one aspect of quality for tomato and tomato products. Carotenoid pigments are responsible for the red and orange colors of tomato fruit, and thus color is also of dietary interest. The aims of this study were (1) to determine the relative importance of field sampling and analytical replication when measuring lycopene and beta-carotene in tomato fruit and (2) to determine the effect of yellow shoulder disorder (YSD) on the content of lycopene and beta-carotene in tomato juice and tissue. Our results show that increasing biological replications is an efficient strategy for reducing the experimental error associated with measurements of lycopene and beta-carotene. Analytical replications did not contribute significantly to observed variation, and therefore experimental efficiency will be gained by reducing analytical replications while increasing field replication. We found that YSD significantly reduces lycopene in affected tissue and in juice made from affected fruit. In contrast, beta-carotene concentrations were only reduced in affected tissue but were not significantly reduced in juice. With increasing interest in biofortified crops, modulating the carotenoid profile in tomato by minimizing YSD symptoms represents a strategy for improving tomato fruit quality that is currently supported by grower contract structure and processor grades.  相似文献   

13.
Bell pepper (Capsicum annuum var annuum L.), cv Pip, transplants were established at 31 and 46 cm in‐rows on bare soil and drip irrigated on a twice weekly schedule. A base rate of fertilizer was applied either in one preplant application or in two (preplant and first flower set) or three (preplant, first flower set, after the midseason harvest) split applications. Additional fertilizer was applied in excess of the base rate on a predetermined schedule or after significant yield decline ('as needed'). Concentrations of 12 elements in leaf and fruit tissues were determined throughout the growing season. The three‐split application of the base rate of fertilizer increased total yield. Plants spaced at 46 cm had increased total and marketable yield in one year. Interactions of fertilizer treatment and plant spacing did not affect total yield. In one year when additional fertilizer was applied ‘as needed’, plants spaced at 31 cm produced more marketable yield than plants spaced at 46 cm. Nutrients in leaves and fruit did not respond to fertilizer treatment or spacing. In leaves and fruit, concentrations of elements increased, decreased/or stayed the same in both years. For leaves, exceptions were Cu, Mn, and N. For fruit, exceptions were Al, Fe, K, and N. A base level application of fertilizer applied preplant was sufficient to support marketable fruit production.  相似文献   

14.
Quality and elemental content of fruit from internal tree canopies were compared with those from external canopy positions in 4 citrus varieties: ‘Kinnow’ mandarin; ‘Redblush’ grapefruit; ‘Valencia’ orange; and ‘Lisbon’ lemon. Fruit weight, total juice per fruit, peel fresh and dry weight, and rind thickness of fruit from internal canopies of all 4 varieties were significantly higher compared with external fruit. Mandarin, grapefruit, and orange fruit from external canopies had higher soluble solids and specific gravity. Fruit from internal canopies of all varieties had generally higher peel concentrations (% dry weight) of N, P and K due to a dilution effect, while the opposite condition existed in mandarin when these elements were expressed on a percent fresh weight basis. Peel Mg and S from external fruit were higher in all varieties, expressed as percentages of either dry weight or fresh weight. Nitrogen content of mandarin and orange juice and Ca content of grapefruit and lemon juice from external fruit were significantly higher compared to those from internal canopy fruit. Elimination of fruit quality and mineral variations as a result of canopy positions is recommended by the means of cultural practices.  相似文献   

15.
Two peach cultivars, Redhaven and Royal Glory, grafted on seven different rootstocks (Adesoto, Barrier 1, GF 677, Ishtara, Monegro, Penta, and peach seedling) were analyzed for tree vigor and yield. Fruit of similar ripeness (fruit firmness) was analyzed in terms of pomological (fruit weight, soluble solids content) and biochemical parameters (individual sugars, organic acids, phenolic acids in the flesh and peel, as well as flavonols and anthocyanins in the peel). A uniform effect of rootstock on tree size was evident in the cases of both cultivars. The Ishtara rootstock induced weak tree growth; Adesoto, Penta and peach seedling semivigorous growth; and Barrier 1, GF 677, and Monegro vigorous tree growth. We recorded higher yields in the Redhaven cultivar, while no significant differences in yield in the fourth growing season were found among the rootstocks for each cultivar. Rootstock had no effect on soluble solids in the Redhaven cultivar, while in the Royal Glory it did. Penta yielded the highest soluble solids content levels, while Adesoto and Monegro were associated with low levels. In the fruit from both cultivars, the rootstock had a significant influence on individual sugars, organic acids, and phenolic acids in the pulp. We also found that phenolic acids in the pulp and skin were more affected by the rootstock than other secondary metabolites analyzed, regardless of the cultivar.  相似文献   

16.
The effect of cultivation practices on fruit quality and antioxidant capacity in highbush blueberries var. Bluecrop (Vaccinium corymbosum L.) was evaluated from random samples of commercial late harvest fields in New Jersey. Results from this study showed that blueberry fruit grown from organic culture yielded significantly higher sugars (fructose and glucose), malic acid, total phenolics, total anthocyanins, and antioxidant activity (ORAC) than fruit from the conventional culture. In organically cultured fruit, the average values for the ORAC, total anthocyanins, and total phenolic content were 46.14 micromol of Trolox (TE)/g of fresh weight (fwt), 131.2 mg/100 g of fwt, and 319.3 mg/100 g of fwt, respectively. In conventionally cultured fruit, the average values for the ORAC, total anthocyanin, and total phenol content were 30.8 micromol of TE/g of fwt, 82.4 mg/100 g of fwt, and 190.3 mg/100 g of fwt, respectively. The organic culture also produced fruit with higher contents of myricetin 3-arabinoside, quercetin 3-glucoside, delphinidin 3-galactoside, delphinidin 3-glucoside, delphinidin 3-arabinoside, petunidin 3-galactoside, petunidin 3-glucoside, and malvidin 3-arabinoside than conventional culture. There was a significant correlation between the ORAC values and total phenolics and total anthocyanins. These results indicate that even though there were variations in phytonutrient content among individual farms within each cultural system, significant differences between two cultivation practices were evident.  相似文献   

17.
荔枝果实采后商品化处理和贮藏技术   总被引：8，自引：4，他引：8  
荔枝是我国南方著名的主要亚热带果树，但其果实成熟于高温季节，采后由于果皮褐变(即失去红色)和果实腐烂而使果实迅速劣变，常温下的采后寿命少于3 d，这种短的采后寿命严格限制荔枝的长距离贮运、销售和消费。因此，荔枝采后技术研究成为荔枝生产的关键问题。该文全面地介绍了荔枝果实采后腐烂和损失的原因（即荔枝果实的结构特性、生理和病理原因），荔枝果实采后商品化处理和贮藏技术，包括不同品种的耐贮运性、采收成熟度和采收方法、选别和分级、杀菌剂浸泡、减少失水处理、减少果皮褐变和保持果实红色处理（如熏硫处理、酸浸或塑料包装）、检疫杀虫处理、预冷、包装、贮藏（常温贮藏、低温贮藏、气调贮藏、自发气调贮藏）、运输和销售。  相似文献   

18.
Apple and pear fruits are important sources of secondary plant metabolites and one of the major sources of dietary phenolics consumed all year round. The aim of this work was to identify the main variables influencing phenolic content and antioxidant capacity in apples. Higher phenolic and antioxidant contents were observed in some varieties (such as the Delbar Estival apple and Durondeau pear). Storage conditions were important. Our results also showed that fruits should be consumed rapidly after purchase and with their peel. After one week of domestic storage, the ascorbic acid content was found to decrease by 75%. Peeling led to a more than 25% decrease in total phenolics and ascorbic acid. The harvest time (at normal ripeness) had only a limited impact, but significant year-to-year variations were observed. In conclusion, well-chosen and well-stored apples and pears may contribute to an antioxidant-rich diet if consumed rapidly and with their peel.  相似文献   

19.
套袋对马家柚果实外观及内在品质的影响   总被引：2，自引：0，他引：2  
为提升江西省特色品种马家柚果实品质,以不套袋处理为对照(CK),研究了5种纸袋类型[单层黄色纸袋(T1)、双层外黄内黑纸袋(T2)、三层外黄内黑纸袋(T3)、双层外红内黑纸袋(T4)、三层外红内黑纸袋(T5)]和4个摘袋时期[9月25日(Z1)、10月10日(Z2)、10月25日(Z3)、11月10日(Z4)]对马家柚果实外观及内在品质的影响。结果表明,使用双层或三层纸袋套袋的马家柚果实外观品质(CCI值为-0.38~-0.08)显著高于不套袋和套单层纸袋处理(CCI值为-1.69~-1.40),但不同颜色对品质的影响差异较小。套袋对马家柚的果型、可食率和果实主要内含物(总糖、可滴定酸、Vc等)含量无显著影响,而T2、T3、T4在增加主要类胡萝卜素含量方面效果更好,其中T3的果实β-胡萝卜素含量最高(22.64 μg·g-1),T2的番茄红素含量最高(29.06 μg·g-1)。不同摘袋时期处理并不会显著改变马家柚原有的果型、可食率和果实主要内含物含量,但对果皮和果肉的色泽以及主要类胡萝卜素含量会产生影响,其中Z3的果实果皮色泽最佳(CCI值为26.44),且果实β-胡萝卜素(23.17 μg·g-1)和番茄红素含量(29.14 μg·g-1)最高,但与带袋采收(Z4)无显著差异。综合劳动力考虑,以套袋后带袋采收为佳。本研究结果为改善马家柚的果实品质提供了理论依据。  相似文献   

20.
>Quality and mineral content of fruit from internal tree canopies were compared with those from external canopy positions in 4 citrus varities: ‘Kinnow’ mandarin; ‘Redblush’ grapefruit; ‘Valencia’ orange; and ‘Lisbon’ lemon. Fruit weight, total juice per fruit, peel fresh and dry weight, and rind thickness of fruit from internal canopies of all 4 varieties were significantly higher compared with external fruit. Mandarin, grapefruit, and orange fruit from external canopies had higher soluble solids and specific gravity. Fruit from internal canopies of all varieties had generally higher peel concentrations (% dry weight) of N, P and K due to a dilution effect, while the opposite condition existed in mandarin when these elements were expressed on a percent fresh weight basis. Peel Mg and S from external fruit were higher in all varieties, expressed as percentages of either dry weight or fresh weight. Nitrogen content of mandarin and orange juice and Ca content of grapefruit and lemon juice from external fruit were significantly higher compared to those from internal canopy fruit. Elimination of fruit quality and mineral variations as a result of canopy positions is recommended by the means of cultural practices.  相似文献   

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