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1.
Transverse concentration gradients differed between Cox and Spartan apples: Spartan apples had higher proportions of calcium and phosphorus in the core, and Cox apples had higher proportions of phosphorus in the inner cortex. Differences in magnesium gradients varied with year. Fruit variety had little effect on longitudinal gradients.  相似文献   

2.
The firmness and mean fruit weight, at harvest, of Cox's Orange Pippin apples from a soil management and N fertiliser trial planted in 1972 were measured from 1979 to 1985 (excluding 1984). Trees growing in overall herbicide, or in 0.3-m herbicide-treated strips with irrigated grassed alleyways, produced significantly softer and/or larger apples than those from trees growing in unirrigated grass with narrow (0.3 m) or wide (1.7 m) herbicide-treated strips in 1982 and 1983. Both these years had drier than average summers. N fertiliser applied annually produced slightly larger and softer apples at 189 kg N ha?1 than at 63 kg N ha?1.  相似文献   

3.
Transverse calcium redistribution from the cores to the outer zones of the fruit was interrupted for a short period when calcium was imported by the cores of both Cox and Spartan apples, especially at 3.5°C. Bitter pit lesions developed in mid and outer cortical tissues of Cox fruit stored at 3.5°C 2 to 4 weeks after calcium concentrations in these zones were reduced. Redistribution of magnesium from the outer zones to the cores of Spartan apples occurred during storage at 3.5°C but was inhibited at 0°C. Redistribution of magnesium in Cox's Orange Pippin apples was mainly from inner cortex to the core and outer zones at 3.5°C and from central to outer zones at 0°C, but immediately low temperature breakdown become evident at 0°C, magnesium was transferred from the peel and core to the affected zones. The redistribution of phosphorus to the cores, which occurred in Spartan apples (resistant to low temperature breakdown) stored at either 3.5°C or 0°C was barely evident in Cox fruit (susceptible to low temperature breakdown) stored at 3.5°C and did not occur at 0°C. Irrigated grass compared with overall herbicide soil management increased the proportion of calcium in the core zones of both Cox and Spartan apples and the proportion of magnesium in the core zone of Spartan apples at harvest. Irrigated grass management also increased the rate of calcium redistribution in Cox and Spartan fruit during storage and altered magnesium redistribution in Spartan apples stored at 0°C.  相似文献   

4.
Transverse distribution patterns of calcium, magnesium and phosphorus in Cox's Orange Pippin apples at harvest and subsequent redistribution patterns during storage in air at 0°C were measured. Distribution and redistribution patterns differed from those in Spartan apples measured in the previous year. Orchard calcium sprays increased the proportion of calcium in the outer parts and slightly increased the proportion of magnesium towards the centre of the fruit. Late summer pruning slightly increased the proportion of magnesium in the core at harvest and increased the rate of redistribution of calcium from the core to the outer fruit parts during storage. Redistribution patterns, especially those of magnesium, were drastically altered when low temperature breakdown developed and minerals moved into the affected zones.  相似文献   

5.
The objective of this study was to determine the nutritional composition of the breast, claw meat and hepatopancreas of the blue crab (Callinectes sapidus). Samples were subjected to proximate (protein, fat, ash and moisture) and calcium, magnesium, phosphorus, potassium and sodium (Ca, Mg, P, K and Na) analyses. Protein, fat, ash and moisture of the breast, claw meat and hepatopancreas of the blue crab averaged 19.05, 0.59, 2.10 and 76.85 g/100 g, respectively. The results have revealed that this species is a rich source of protein, Ca, Mg, P and Na. Claw meat had higher protein concentrations (19.55 g/100 g) than both breast meat and hepatopancreas (18.81 g/100 g). Na was predominant element among minerals analysed. There were significant differences between Ca, Mg, P, K and Na contents of claw, breast meat and hepatopancreas of the blue crab. Information on the nutrient composition is needed to facilitate the processing, utilisation and marketing of blue crab products. Blue crab could balance human nutrition and could be used as an alternative dietary supplement of proteins and mineral matter.  相似文献   

6.
Sprays containing Ca2+, Mg2+ or Ti4+ were applied to peach trees in several combinations. Effects of treatments on the commercial quality of fruits, especially focused on improving their mechanical properties, are discussed. All treatments containing titanium increased tree performance (branch elongation, flowering and fruit set intensities) and fruit size. At harvest, fruits from Ti‐treated trees showed improved resistance to compression and penetration, as well as a decrease in weight loss during postharvest storage. A similar response was obtained for external colour, though all treatments seemed to delay somewhat the apparent ripening status. Nevertheless, fruits from Ti‐treated trees showed better behaviour in the evolution of colour parameters during storage than did control fruits. Titanium application showed significant increases in iron, copper and zinc concentrations in the peel and calcium concentration in the peel and flesh. This improvement in calcium absorption is explained as a consequence of the beneficial effect of titanium on the absorption, translocation and assimilation processes. Copyright © 2004 Society of Chemical Industry  相似文献   

7.
The problems of relating low fruit calcium concentrations in stored apples to the development of bitter pit lesions are reviewed. They include nomenclature, anomalous fruit analyses, variability in the susceptibility of apples to pitting and in the time and rate of pit development, effect of harvest date, accumulation of calcium in pitted tissue and the apparant translocation of calcium during storage from the core into zones of tissue most at risk. Recent evidence suggests that bitter pit lesions are induced by the removal of calcium from these outer zones to meet intermittent demands by the core tissue.  相似文献   

8.
Analyses of apples, of various varieties and from many sources, affected by lenticel blotch pit and/or watercore showed that calcium concentrations in the fruit were usually extremely low. The severity of lenticel blotch pit, either on the tree or during storage, increased with decreasing concentrations of calcium and/or increasing concentrations of potassium. Split and cracked apples had lower concentrations of calcium or higher concentrations of potassium than sound fruit from the same sources. The disorders usually occurred when mean concentrations of calcium in bulked random samples of fruit fell below 4 mg 100 g?1 fresh wt and lenticel spotting was noted on apples with concentrations at this level. Incidences of these disorders in the orchard therefore indicate that the fruit is likely to develop bitter pit and breakdown during storage.  相似文献   

9.
Milk minerals are important for calf growth, and they have other roles as well, such as immune regulation. This 2-yr study examined content of Ca, P, Mg, Na, K, Fe, and Zn in milk of 54 Iberian red deer hinds through 18 wk of lactation. Mean mineral composition of fresh milk was ash = 1.168 ± 0.007%, Ca = 2,330 ± 20 mg/kg, P = 640 ± 10 mg/kg, K = 1,100 ± 10 mg/kg, Na = 385 ± 3 mg/kg, Mg = 138 ± 1 mg/kg, Zn = 12.5 ± 0.2 mg/kg, and Fe = 0.65 ± 0.03 mg/kg. All minerals except Mg varied by week of lactation, but variation was usually <10% except for Fe (83% variation) and Zn (30% variation); both of those minerals increased as lactation proceeded. Increased concentrations of Fe and Zn in later lactation compensated for the reduction in milk production in mid and late lactation such that daily production was less variable for Fe (55% variation) or Zn (79% variation) than for other minerals (118 to 135% variation). Potassium content of milk decreased across time, but that effect occurred primarily during the last few weeks of lactation. Calving later vs. early in the calving season had variable effects on concentrations of different minerals: P, Mg, and K concentrations were not affected; Ca, Mg, and Na were all lower in milk from later calving hinds; and both Fe and Zn had higher concentrations in milk from hinds that calved later in the season. Lactating hinds seem to maintain a more stable daily yield of the microminerals Fe and Zn in milk compared with more variable concentrations of macrominerals as lactation progresses. Because of the essential role of Fe and Zn in immune function, a more stable supply of those minerals might be important to the health of growing red deer calves.  相似文献   

10.
Flesh colour, which is affected by cultivars and browning, can largely impact consumer acceptance in fresh-cut apples. The study profiled phenolic metabolites from apple flesh of twenty-three cultivars by widely targeted metabolomics. Comparison among white- and yellow-fleshed cultivars showed fifteen phenolics, mainly quercetin 3-O-glucoside, hyperoside, hesperetin 5-O-glucoside and cymaroside, in white-fleshed apples were significantly higher than those in yellow-fleshed apples. It may indicate a metabolite basis of yellow and white flesh colour, and better potential nutrition in white-fleshed apples. In addition, ten phenolic metabolites including five cyanidin glycosides showed significant differences between the highest and the lowest browning groups, indicating them may be crucial in browning of fresh-cut apple. This work elucidates the differences of phenolic profiles among apple cultivars with different flesh colour and provides useful data to evaluate the suitability of apple for fresh-cut processing.  相似文献   

11.
In 1972 an experiment was set up to investigate the long-term effects of herbicide, irrigation and two rates of nitrochalk fertiliser application on soil fertility in a Cox's Orange Pippin apple orchard. Samples taken in 1986 showed that uncultivated soil which had been maintained bare by herbicide had much lower organic C, total N and extractable K and Mg concentrations than soil which had been maintained under grass. Extractable P concentrations were lower in soil under grass than in soil under herbicide. In the absence of grass, soil pH was slightly lower than in its presence. All these effects were much greater at depths above 7·5 cm than below. Irrigation of the grass slightly increased organic C and total N levels at 0–7·5 cm compared with unirrigated grass but had no effect on extractable P, K and Mg. Increasing the fertiliser rate from 63 to 189 kg N ha?1 had no effect on organic C, total N, extractable P and K. Yet, throughout the soil profile, extractable Mg concentrations were greater at the low than at the high N fertiliser rate. In a seedling growth test on soil taken from the orchard in 1988 (and confirmed to be free from residual herbicide), apple seedlings grown in soil which had previously been under grass grew significantly better than those in soil which had been bare. These differences were ascribed to a greater rate of N mineralisation in the soil formerly under grass. The results of this trial indicate that to safeguard soil fertility it is necessary to maintain a grass cover in the orchard. In addition, fertiliser application on newly planted trees should be adjusted to take account of the presence or absence of grass in the previous soil management treatment.  相似文献   

12.
Nutrients and physical properties were determined in terebinth (Pistacia terebinthus L) fruits from ?çel, Turkey to investigate their potential uses. Ripe fruits were evaluated for moisture, crude protein, crude oil, crude fibre, crude energy, ash, HCl‐insoluble ash, essential oil yield, dimethyl sulphite, weight and width/length ratio. Relative density, refractive index, free fatty acids, peroxide value, iodine value, saponification number, unsaponifiable matter and carotenoid content were determined in the fruit oil. The main fatty acids identified by gas chromatography were oleic (52.3%), palmitic (21.3%) and linoleic (19.7%) acids. Contents of Na, K, P, Ca, Fe, Mg, Zn, Cu, Mn, Li, Ni, Pb, S, Se, Cd, Co, Cr, Sr, Ti, V, Ag, Al, As, B, Ba and Bi were also determined in the fruits. The fruits were found to be rich in protein, oil, fibre, unsaturated fatty acids and minerals, suggesting that they may be valuable for food uses. The data may also be useful for the evaluation of nutritional information. Copyright © 2004 Society of Chemical Industry  相似文献   

13.
The purpose of this research was to model the kinetics of adsorption of 1-methylcyclopropene (1-MCP) in apple fruit and non-target solid materials found in apple storage rooms. The process was described by Fick’s second law of diffusion of the gas through the pores of the material coupled with adsorption kinetics of the gas on the material’s binding sites. A finite element formulation of the model, describing the diffusion and adsorption mechanisms separately, was first developed. The values of the relevant parameters were estimated based on headspace measurements of the decrease of 1-MCP in jars containing the different materials. The headspace concentration of 1-MCP was measured using gas chromatography. Apple fruit (Golden Delicious and Jonagold) and the following bin construction materials were investigated: high density polyethylene (HDPE), oak, poplar wood and card lining. The range in the magnitude of the diffusion coefficient, adsorption coefficient, and concentration of active sites in the various solids was 10,000-, 8-, and 30-fold, respectively.  相似文献   

14.
《Journal of dairy science》2023,106(9):6577-6591
The causes of variation in the milk mineral profile of dairy cattle during the first phase of lactation were studied under the hypothesis that the milk mineral profile partially reflects the animals' metabolic status. Correlations between the minerals and the main milk constituents (i.e., protein, fat, and lactose percentages), and their associations with the cows' metabolic status indicators were explored. The metabolic status indicators (MET) that we used were blood energy-protein metabolites [nonesterified fatty acids, β-hydroxybutyrate (BHB), glucose, cholesterol, creatinine, and urea], and liver ultrasound measurements (predicted triacylglycerol liver content, portal vein area, portal vein diameter and liver depth). Milk and blood samples, and ultrasound measurements were taken from 295 Holstein cows belonging to 2 herds and in the first 120 d in milk (DIM). Milk mineral contents were determined by ICP-OES; these were considered the response variable and analyzed through a mixed model which included DIM, parity, milk yield, and MET as fixed effects, and the herd/date as a random effect. The MET traits were divided in tertiles. The results showed that milk protein was positively associated with body condition score (BCS) and glucose, and negatively associated with BHB blood content; milk fat was positively associated with BHB content; milk lactose was positively associated with BCS; and Ca, P, K and S were the minerals with the greatest number of associations with the cows' energy indicators, particularly BCS, predicted triacylglycerol liver content, glucose, BHB and urea. We conclude that the protein, fat, lactose, and mineral contents of milk partially reflect the metabolic adaptation of cows during lactation and within 120 DIM. Variations in the milk mineral profile were consistent with changes in the major milk constituents and the metabolic status of cows.  相似文献   

15.
BACKGROUND: The aim of this research was to identify the differences in volatile compounds, mineral composition, quality parameters and pericarp structure (at different fruit developmental stages) between two South African litchi export cultivars, Mauritius and McLean's Red, in order to provide a better understanding of the plant intraspecific variation. RESULTS: Citronellol and geraniol were predominant in the aroma profile of cv. Mauritius and conferred characteristic floral, rose, citrus and fruity aromas. In cv. McLean's Red, germacrene D was predominant in the sesquiterpene fraction. Germacrene D and muurolene are associated with a woody smell. Cv. Mauritius had lower soluble solid content/titratable acidity ratio and higher ascorbic acid content than cv. McLean's Red. Cv. McLean's Red had lower pericarp hue angle and higher anthocyanin concentration, which correlated negatively. Significant differences in fruit mineral content and pattern of cuticle accumulation were noted between the two cultivars. The parallel cuticular lines formed a network with intercellular ridges and heavy wax deposits in cv. McLean's Red. Cv. Mauritius showed higher weight loss at 25 °C, suggesting that the dense wax deposits and cuticle structure in cv. McLean's Red could limit moisture loss. CONCLUSION: This investigation shows evidence for the lack of sweet and rose‐like fragrance in litchi cv. McLean's Red. It is the first study to compare volatile compounds responsible for the differing aromas of two South African litchi cultivars. Litchi cultivar improvement and breeding programmes are focused on expansion of the season and yield. The reported information is useful for selection of cultivars and for cultivar breeding programmes focusing on fruit quality and storage potential. Copyright © 2008 Society of Chemical Industry  相似文献   

16.
The pulp of the African pear, Dacryodes edulis, was investigated for its nutritional quality and oil characteristics. The crude protein, fat, fibre and carbohydrate contents were 25.9, 31.9, 17.9 and 13.5%, respectively. The pulp was found to contain significant levels of Ca, Mg, K and P. The fatty acid profiles showed a saturated fatty acid content of 50.85% and an unsaturated fatty acid content of 49.14%. The predominant fatty acids were palmitic and oleic acids. The saponification value and iodine value were 201.4 and 59.6. The amino acid profiles showed high contents of the essential amino acids lysine, leucine and threonine.  相似文献   

17.
The fatty acid composition of the extracted oils from ten varieties of cowpea, eighteen varieties of limabean and two of soyabean were determined by gas-liquid chromatography. All the seeds, with the exception of soyabean, were poor sources of oil. The major fatty acids in the cowpea and limabean varieties were linoleic (C18:2), palmitic (C16:0) and linolenic (C18:3) acids. In the soyabeans, linoleic and oleic (C18:1) acids were the major fatty acids. Traces of gadoleic (C20:1), erucic (C22:1) and lignoceric (C24:0) acids were obtained in Cowpea Kano 1696, Farv-13 and Nigeria B7 and in limabean TPL 2 and TPL 187. Considerable variability was encountered among the different fatty acids in the different varieties of cowpea and limabean. This is indicated by the differences in fatty acid composition and the high coefficient of variation obtained for ether extract (28·6 and 46·2% in cowpea and limabean, respectively), lauric acid (100 and 50%, respectively), oleic acid (35·1 and 37·7%, respectively), myristic acid (30 and 30·8%, respectively) and behenic acid (39·4 and 30·4%, respectively). Some of these differences may be genetic.  相似文献   

18.
The aim of this work was to study the effect of high hydrostatic pressure on the bioaccessibility of specific nutrients (antioxidant, minerals and starch) in apple and to establish processing conditions that maximise the health benefits. The apple was pressurised at 500 MPa during 2, 4, 8 and 10 min. The antioxidant activity, mineral and starch content and bioaccessibility of apple samples were significantly affected by the processing and digestion conditions. Therefore, these results indicated that in vitro digestion has a noticeable effect on the antioxidant concentration, IC50, with much lower values (a smaller IC50 value corresponds to a higher antioxidant activity) of apple samples compared with those untreated and non-digestion. Apple has the highest calcium content (30.33 ± 1.94 mg/100 g), iron (14.46 ± 3.49 mg/100 g) and zinc (6.22 ± 0.91 mg/100 g). High hydrostatic pressure increased the mineral contents availability by 2.11–303.00% for calcium, 4.63–10.93% for iron and 8.68–28.93% for zinc. The dialysability and solubility of calcium, iron and zinc with respect to the values for the untreated sample were reduced by this high pressure technique. Consumption of apple under high hydrostatic pressure may supply substantial antioxidants, mineral and starch, which may provide health promoting and disease preventing effects.  相似文献   

19.
The objective of this study was to determine the effects of feeding different supplemental sources of Ca and Mg in the peripartum period, and different dietary levels of Mg postpartum, on plasma mineral status, performance, and aspects of energy metabolism in transition dairy cows. Multiparous Holstein cows (n = 41) were used in a completely randomized design with a 2 × 2 factorial arrangement of treatments starting at 28 d before expected parturition. Main effects were source assignments (CS = common sources of supplemental Ca and Mg, or MA = a blend of common and commercial mineral sources with supplemental minerals primarily from a commercial Ca-Mg dolomite source; MIN-AD, Papillon Agricultural Company Inc., Easton, MD) beginning at 21 d before due date; cows were further randomized within source treatments to 1 of 2 levels of Mg supplementation (LM = formulated postpartum diet Mg at 0.30% of dry matter (DM), or HM = formulated postpartum diet Mg at 0.45% of DM) beginning within 1 d after parturition. Final treatment groups included the following: common source, low Mg (CS-LM, n = 11); common source, high Mg (CS-HM, n = 11); MIN-AD, low Mg (MA-LM, n = 10); and MIN-AD, high Mg (MA-HM, n = 9). Treatment diets were fed and data collected through 42 d in milk. Postpartum plasma Mg concentrations tended to be higher for cows fed HM and cows fed CS, but no effects were observed on peripartum plasma Ca concentrations. Peripartum plasma P concentrations were higher for cows fed MA. Dry matter intake (DMI) in the prepartum period was higher for cows fed MA (CS = 15.9 vs. MA = 16.8 kg/d) and postpartum DMI was higher in some groups depending on week. Plasma nonesterified fatty acid concentrations were lower for cows fed MA during both the prepartum and postpartum periods. A source by level interaction was observed for postpartum plasma β-hydroxybutyrate (BHB) concentrations such that cows fed CS-LM had numerically higher BHB and cows fed MA-LM had numerically lower BHB (geometric means; CS-LM = 7.9, CS-HM = 6.9, MA-LM = 6.3, and MA-HM = 7.3 mg/dL) than cows fed the other 2 treatments. Higher milk fat yield, milk fat content, and fat- and energy-corrected yield during wk 1 for cows fed MA resulted in source by week interactions for these outcomes. This study demonstrated that varying supplemental Ca and Mg sources and feeding rates had minimal effect on plasma Ca status despite differences in plasma Mg and P concentrations. Effects on DMI and plasma energy metabolites suggest an opportunity for strategic use of mineral sources in the transition period to promote metabolic health.  相似文献   

20.
This study evaluated the effect of regulated deficit irrigation (RDI) strategies applied to olive trees (Arbequina cv) during the fruit ripening and harvest periods on oil yield and oil composition. Fatty acid composition, pigments, colour, polyphenol content and stability of oils were evaluated. The results indicate that regulated deficit irrigation induces fruit ripening; at harvest, oil yield increased when water supply was decreased, probably as a consequence of lower water content in the olive. Acidic composition was not affected by irrigation treatments. Irrigation affected pigment content and oil colour primarily during the early stages of olive ripening. RDI increased polyphenol concentration and stability of oils at all picking dates, especially during the first stages of the ripening period, probably owing to water stress. © 2000 Society of Chemical Industry  相似文献   

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