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1.
The consumption of mineral waters is increasing in industrialised countries. High intakes of Ca and other alkalising cations as well as a low acid intake are beneficial to bone. We examined which components of mineral waters are conditioning their Ca content and their alkalinising power, in order to define the optimal profile. European mineral waters were randomly selected on the Internet: 100 waters with less than 200 mg Ca/l (9.98 mEq/l) and fifty with more than 200 mg/l, all with complete data for SO4, P, Cl, Na, K, Mg and Ca, and most also for HCO3. For comparison, forty North American mineral waters were randomly chosen. The potential renal acid load (PRAL) was calculated for each mineral water. North American waters did not reveal significant results because of their low mineralisation. We performed correlations between all eight components in order to explore the properties of the mineral waters. In the European waters, twenty-six out of twenty-eight correlations showed a P value of 0 (acidifying waters), PRAL was positively correlated with SO4, Ca, K and Mg (P < 0.001). In those with PRAL < 0 (alkalinising waters), PRAL was negatively correlated with HCO3, Na, Mg, Ca, K, Cl and SO4 (P < 0.001). SO4 and HCO3 were not found together in high quantities in the same water for geochemical reasons. A high Ca content is associated with either a high SO4 or a high HCO3 content. SO4 theoretically increases Ca excretion, while HCO3 and low PRAL values are associated with positive effects on bone. Therefore, the best waters for bone health are rich in both HCO3 and Ca, and by consequence low in SO4.  相似文献   

2.
The purpose of this study was to calculate the potential renal acid load (PRAL) of selected, frequently consumed foods. A physiologically based calculation model was recently validated to yield an appropriate estimate of renal net acid excretion (NAE); the model depends primarily on nutrient intake data. When nutrient data from actual food composition tables were used, the calculation model yielded PRAL values that ranged from an average maximum of 23.6 mEq/100 g for certain hard cheeses over 0 mEq/100 g for fats and oils to an average minimum of approximately −3 mEq/100 g for fruits and fruit juices and vegetables. By means of these PRAL data (summed according to the amounts of foods and beverages consumed daily and by an estimate of excretion of organic acids [based on body size]), the daily NAE can be calculated. This calculation methodology, primarily based on PRAL, allows an appropriate prediction of the effects of diet on the acidity of urine. For practical applicability in dietetic prevention of recurrent urolithiasis or in other fields of dietetics, the additionally determined correlation (r=.83; P<.001) between NAE and urine pH can be used to ascertain NAE target values for a desired urine pH modification. J Am Diet Assoc. 1995; 95:791-797.  相似文献   

3.
Our objective in this study was to determine the effects of a high-protein and high-potential renal acid load (PRAL) diet on calcium (Ca) absorption and retention and markers of bone metabolism. In a randomized crossover design, 16 postmenopausal women consumed 2 diets: 1 with low protein and low PRAL (LPLP; total protein: 61 g/d; PRAL: -48 mEq/d) and 1 with high protein and high PRAL (HPHP; total protein: 118 g/d; PRAL: 33 mEq/d) for 7 wk each separated by a 1-wk break. Ca absorption was measured by whole body scintillation counting of radio-labeled (47)Ca. Compared with the LPLP diet, the HPHP diet increased participants' serum IGF-I concentrations (P < 0.0001), decreased serum intact PTH concentrations (P < 0.001), and increased fractional (47)Ca absorption (mean ± pooled SD: 22.3 vs. 26.5 ± 5.4%; P < 0.05) and urinary Ca excretion (156 vs. 203 ± 63 mg/d; P = 0.005). The net difference between the amount of Ca absorbed and excreted in urine did not differ between 2 diet periods (55 vs. 28 ± 51 mg/d). The dietary treatments did not affect other markers of bone metabolism. In summary, a diet high in protein and PRAL increases the fractional absorption of dietary Ca, which partially compensates for increased urinary Ca, in postmenopausal women. The increased IGF-I and decreased PTH concentrations in serum, with no change in biomarkers of bone resorption or formation, indicate a high-protein diet has no adverse effects on bone health.  相似文献   

4.
Sprinters are advised to include additional protein sources in their diet. Basal metabolism and vigorous physical activities generate hydrogen ions that need to be buffered. The present follow-up study estimates the dietary potential renal acid load (PRAL) and net endogenous acid production (NEAP) in adolescent sprint athletes. Seven-day food diaries and anthropometrics of 60 adolescent sprint athletes (mean age at start 14.7 ± 1.9 years) were collected every six months over a three year period. Comparisons were made between athletes with a negative (PRAL(-)) versus positive PRAL (PRAL(+)). For the entire sample, mean PRAL values of up to 6 mEq/day were slightly positive despite a relatively high protein intake of around 1.5 g/kg. The NEAP ranging between 42 and 46 mEq/day remained stable during the study period. Athletes with a PRAL(-) (-8 to -10 mEq/day) consumed significantly more fruit and fruit juice than athletes with a PRAL(+) (+9 to 14 mEq/day). Athletes with a PRAL(+) did not consume more meat, fish and poultry than athletes with a PRAL(-). Grains and dairy products were only discriminative between the two groups on one measurement occasion. Lowering the PRAL can be obtained by increasing the consumption of potatoes, fruits, vegetables and vegetable soup.  相似文献   

5.
Macromineral and microelement contents were measured by inductively coupled plasma-optical emission spectrometry in 51 dairy products (milk, four types of cheese and butter). Significant differences in the concentrations of Ca, K, Na, Mg, Zn and Cu were observed (p < 0.05, all) between dairy products. Higher levels of Ca, Na, Mg and Se were measured in hard cheese than in semi-hard, fresh and cream cheese samples. The highest mean levels of elements were measured in products (mg kg−1): milk: K 2070; hard fat cheese: Ca 10,700, Na 10,300, Mg 440, Zn 91.3, Se 0.78; cream cheese: Cu 3.12, Fe 3.9; butter: Se 0.79. The estimated daily intakes (EDIs) calculated for milk show contribution to the recommended dietary allowance (RDA) for the elements (%): Ca 42, K 13.2, Mg 10.3–13.3, Zn 11.4–15.7, Se 13.1. The highest contribution of elements to the RDA values was determined for hard fat cheese (%): Na 7.93, Zn 16.6–22.8, Se 28.4. However, a contribution to the RDA of less than 1% was determined for K, Mg and Fe in cheeses. The contribution of Cu to the RDA value ranged in cheese samples between 2.78 and 6.93%, though this was less than 1% in milk.  相似文献   

6.
The objective of this study was to compare the nutritional value of three parenteral fluids: a conventional solution (400 milliosmoles/liter, containing Na, K, and Cl in 5% glucose); the concentrated hyperalimentation solution of Dudrick (1,800 milliosmoles/liter, containing Na, K, Cl, Mg, Ca, P, and amino acids in 20% glucose); and an experimental solution (900 millisomoles/liter, containing Na, K, Cl, Mg, Ca, P, and amino acids in 6.5% glucose). These three solutions are termed P400, C1,800, and P900, respectively. Preliminary studies showed that when 5 mg of cortisol/liter were added to P900, this fluid could be infused through peripheral veins for as long a time (average 114 hr) as P400 before local reaction necessitated changing the site. When P400 was infused in undernourished subjects without oral intake, balances of N, P, Mg, and Ca/70 kg of body weight per day were strongly negative (-4 g, -0.4 g, -6 mEq, and -0.2 g, respectively), whereas balances of K were about zero and those of Na and Cl were positive. Weight loss occurred. In the same patients, P900 containing 5 mg of cortisol/liter converted balances of N, P, Mg, and K to positive, and stimulated weight gain. Comparison of P900 (containing cortisol) and C1,800 in three emaciated subjects showed that the latter fluid caused a 2 to 4 times greater degree of positive balance in N, P, K, and Mg than the former. Comparison of P900 (containing cortisol) + 670-1700 cal by mouth with C1,800 in four undernourished subjects showed no statistically significant difference between these two programs. Conclusions: by adding 5 mg of cortisol/liter to P900, the fluid can be infused through peripheral veins. P900 is intermediate in nutritional value between P400 and C1,800. P900 without oral supplement prevents negative balance of all elements except Ca. P900 + daily oral intake of 670-1700 cal is nutritionally equivalent to C1,800.  相似文献   

7.
The chemical characteristics, fatty acid and conjugated linoleic acid (CLA) contents and cholesterol levels of some traditional Turkish cheeses that are consumed mostly in Turkey were determined in this study. The fatty acid and cholesterol contents and CLA amount of cheeses were analysed as methyl esters by gas chromatography. The aim of this study was to determine the nutritional profile of some Turkish cheeses produced by traditional methods. The major fatty acids of the cheeses were palmitic acid (C(16:0)) and oleic acid (C(18:1)). The saturated fatty acid content of samples changed between 60.80% and 76.57%, while the monounsaturated fatty acid content ranged from 21.42% to 34.05% and the polyunsaturated fatty acid content was between 1.47% and 3.59%. The CLA contents of the cheeses ranged from 0.44 to 1.04 g/100 g in fat. The cholesterol levels of the samples were determined as 44.6-147.69 mg/100 g in cheese.  相似文献   

8.
The aim of this study was to update the Icelandic Food Composition Database with respect to minerals (Ca, K, Mg, Na, and P) and trace elements (Cu, Fe, Hg, Se, and Zn) in frequently consumed agricultural products and to study the seasonal and geographical variation for these elements. Five food products typical for the Icelandic food basket were analysed: whole milk, fresh cheese (skyr), firm cheese (Gouda), lamb meat and minced beef together with skimmed milk, cream and whey. Concentrations of minerals and trace elements were determined by an inductively coupled plasma mass spectrometer (ICP-MS). Seasonal and geographical variation in whole milk was found only for selenium. Concentration of selenium in meat was variable and especially low for beef (1.4–9.6 μg/100 g fresh weight). Mercury was below the detection limit of 0.3 μg/100 g except for one sample of cheese. Skyr was rich in protein, calcium and phosphorus and retains almost all selenium in the skimmed milk used for its production. Skyr whey contains more calcium, magnesium, phosphorus and zinc than cheese whey. Skyr whey is a nutritious product, almost as rich in calcium, potassium and zinc as whole milk and could be used more by the Icelandic food industry.  相似文献   

9.
Survival of the probiotic adjunct culture Bifidobacterium longum and cheese starters during ripening of white brined cheese, effect of the probiotic culture on physicochemical properties and sensorial attributes of cheeses were investigated throughout 90?d of ripening. Bifidobacterium longum were able to survive at higher levels (>107?cfu/g cheese) than the therapeutic minimum (106–107?cfu/g cheese) after 90?d and did not have any negative effect on the survival of Streptococcus spp. (including common cheese starters). Incorporation of the probiotic adjunct into white brined cheese and high levels of their survival rates during ripening had an insignificant effect on the composition of cheeses. Results indicated that white brined cheese is a suitable food matrix for the delivery of B. longum used in this study, and white brined cheeses with B. longum may be considered as a probiotic dairy product.  相似文献   

10.
The chemical characteristics, fatty acid and conjugated linoleic acid (CLA) contents and cholesterol levels of some traditional Turkish cheeses that are consumed mostly in Turkey were determined in this study. The fatty acid and cholesterol contents and CLA amount of cheeses were analysed as methyl esters by gas chromatography. The aim of this study was to determine the nutritional profile of some Turkish cheeses produced by traditional methods. The major fatty acids of the cheeses were palmitic acid (C16:0) and oleic acid (C18:1). The saturated fatty acid content of samples changed between 60.80% and 76.57%, while the monounsaturated fatty acid content ranged from 21.42% to 34.05% and the polyunsaturated fatty acid content was between 1.47% and 3.59%. The CLA contents of the cheeses ranged from 0.44 to 1.04 g/100 g in fat. The cholesterol levels of the samples were determined as 44.6–147.69 mg/100 g in cheese.  相似文献   

11.
Contents of trace elements (copper, zinc, iron, and manganese) were determined in melted cheeses, mold-ripening semi-hard and soft types purchased in 2005 at local shops. The AAS technique was used. Material for study was produced by different Dairy Centers all over Poland in Lublin, Mazowsze, Opole, Podlasie, Silesia, and Wielkopolska regions. Zinc and iron levels in melted cheeses were significantly higher (p < or = 0.05) as compared to mold-ripening soft and semi-hard cheeses. The highest zinc and iron concentrations were found in the samples of Sertop and Jal cheese. The lowest contents were found in Mabelle cheese. Rycki Edam cheese was characterized by highest level of manganese, and Mabelle--by the lowest. However, copper, iron, and manganese contents in all cheese samples could be considered as low and not hazardous for consumer's.  相似文献   

12.
The gross and mineral composition and the most relevant physico-chemical parameters were determined in five batches of León cow's milk cheese throughout ripening and in the milk used in their manufacture. The milk used in the manufacture of this cheese is characterized by having high values of fat and total solids; the mineral composition and the values of pH do not differ significantly from those observed in cow's milk from different origins. During ripening, León cow's milk cheese undergoes a very intense dehydration, due to this, the final values of moisture andAw are among the lowest observed in cow's milk cheese. The fat contents in this cheese are placed in the higher extreme of the range of values observed in other cheeses. The presence of residual lactose in cheese after 90 days (end of ripening) is exceptional. During curdling a very intense acidification takes place as a consequence of which very low values of pH are reached in the curd (around 4.6) and remain during ripening with minimum variation, with the final values of pH being among the lowest found in cow's milk cheese. As a consequence of acidification during curdling, the minerals for the most part bound to the micelle of casein (Ca, P, Mg and Zn) underwent a solubilization and were lost in significant amounts in the whey. The contents of these minerals and of total ash at the end of ripening are clearly lower than those observed in other similar cow's milk cheeses.  相似文献   

13.
Wild-growing mushrooms could be a potential source of mineral elements The aim of this study was to analyze the mineral composition of 18 species of wild-growing mushrooms collected in a natural park from the Spanish southeast (province of Granada). Ca, Mg, K, Na, Fe, Cu and Zn, were determined by flame atomic absorption spectroscopy and P was analyzed colorimetrically by the vanadomolybdate procedure; the accuracy of methods was assessed by the use of certified reference materials. The contribution of mushrooms consumption to the mineral daily recommended intakes was calculated. Although large variations were observed between species, the most abundant mineral elements in the analyzed mushrooms were K and P, with average contents of 29.3 ± 8.1 and 8.60 ± 4.8 g/kg dry matter (dm), respectively. Low Na concentrations were observed (26.5–579 mg/kg dm), with the only exception of Amanita ovoidea, and high Fe values, exceeding in some cases 1000 mg/kg dm (such as in Lactarius deliciosus and Morchella conica). Mushrooms may be significant contributors of K and P in the human diet and also good sources of trace elements, especially Cu and Fe, providing negligible quantities of Na. Strong correlations were observed for Ca/Mg and Cu/Zn contents in the mushrooms analyzed.  相似文献   

14.
采用原子吸收光谱仪 ,对槐花蜜、枣花蜜、荆条蜜 3种蜂蜜中的铁、锌、钙、钾、镁、钠、铜、锰 8种元素的含量进行了测定 ,结果表明 ,不同种类的蜂蜜所含的微量元素也有差别 ,蜂蜜中含有一定的铁、钙、钾、钠元素 ,锌、镁、铜等元素的含量很低 ,锰元素在 3种蜂蜜中均未检出。  相似文献   

15.
There is a need to increase the options for vitamin D fortification. We have developed a method to fortify hard cheese with vitamin D. Our aim was to characterize the bioavailability of vitamin D from fortified cheeses. Eighty adults were randomized to weekly servings of fortified cheddar cheese (DC) (34 g; n = 20); fortified low-fat cheese (DLF) (41 g; n = 10); liquid vitamin D supplement (1 mL), taken with food (DS+) (n = 20) or without food (DS-) (n = 10); placebo cheddar cheese (n = 10); or placebo supplement (n = 10). The treatments contained 28,000 IU cholecalciferol (vitamin D3), equivalent to 4000 IU (100 microg/d). The primary outcome was the comparison of vitamin D bioavailability, as measured by the serum 25-hydroxyvitamin D [25(OH)D] response, between fortified cheeses and supplement. In the placebo groups, initial 25(OH)D, 55.0 +/- 25.3 nmol/L, declined over the 8-wk winter protocol, to 50.7 +/- 24.2 nmol/L (P = 0.046). In the vitamin D-treated groups, the mean increases in 25(OH)D over 8 wk were: 65.3 +/- 24.1 (DC), 69.4 +/- 21.7 (DLF), 59.3 +/- 23.3 (DS+), and 59.3 +/- 19.6 nmol/L (DS-); these changes differed from the placebo groups (P < 0.0001) but not from one another (P = 0.62). Compared with baseline, serum parathyroid hormone decreased with both fortification (P = 0.003) and supplementation (P = 0.012). These data demonstrate that vitamin D is equally bioavailable from fortified hard cheeses and supplements, making cheese suitable for vitamin D fortification.  相似文献   

16.
Mild metabolic acidosis, which can be caused by diet, may adversely affect cardiometabolic risk factors, possibly by increasing cortisol production. Methodologies for estimating diet-induced acid-base load using dietary-intake information have been established. To our knowledge, however, the possible association between dietary acid-base load and cardiometabolic risk factors has not been investigated. We cross-sectionally examined associations between dietary acid-base load and cardiometabolic risk factors in a free-living population. The subjects were 1136 female Japanese dietetic students aged 18-22 years. Dietary acid-base load was characterized as the potential renal acid load (PRAL), which was determined using an algorithm including dietary protein, P, K, Ca and Mg, as well as the ratio of dietary protein to K (Pro:K). Estimates of each nutrient were obtained from a validated comprehensive self-administered diet history questionnaire. Body height and weight, waist circumference and blood pressure were measured. Fasting blood samples were collected. After adjustment for potential confounding factors, higher PRAL and Pro:K (more acidic dietary acid-base loads) were associated with higher systolic and diastolic blood pressure (P for trend = 0.028 and 0.035 for PRAL and 0.012 and 0.009 for Pro:K, respectively). PRAL was also independently positively associated with total and LDL-cholesterol (n 1121; P for trend = 0.042 and 0.021, respectively). Additionally, Pro:K showed an independent positive association with BMI and waist circumference (P for trend = 0.024 and 0.012, respectively). In conclusion, more acidic dietary acid-base load was independently associated with adverse profile of several cardiometabolic risk factors in free-living young Japanese women.  相似文献   

17.
Cholesterol contents and other nutrient parameters of Greek cheeses, namely water, fat, protein, ash, lactic acid, salt, caloric value and fatty acid content, were assayed using chemical and chromatographic methods. The cholesterol concentrations on fresh weight (f.w.) basis (mg/100 g) in soft (67.9, range 51.3–85.3), whey-soft (49.4, range 39.0–57.9), Manouri (99.5, range 83.9–115.2), semi-hard (90.8 range 81.0–102.6) and hard (93.1 range 76.2–110.5) categories were correlated to European cheese varieties. Respective mean values (g/100 g f.w.) of saturated, monounsaturated and polyunsaturated fatty acids were: soft 17.2, 5.0, 0.7, whey-soft 11.5, 3.1, 0.6, Manouri 34.1, 9.4, 1.3, semi-hard 21.4, 18.3, 5.56, 1.03 and hard 21.6, 6.6, 1.2, while all pooled averages were 19.1, 5.5 and 0.9, respectively. Trans fatty acids ranged within 0.36–2.46 (g/100 g f.w.) with an average of 1.06 for all types. The main trans fatty acids (16:1, 18:1, 18:2) contents (g/100 g f.w.) are also given.The fat/protein ratio indicated a relatively higher fat content of Greek cheese if compared to similar cheese types of other European countries. A very strong correlation between cholesterol and fat content was found for pooled data, although the correlation was weaker within individual cheese varieties. In addition, a trend of decreasing cholesterol/fat and cholesterol/energy ratios with increasing fat content suggests that Greek cheeses may not be overloaded with cholesterol.  相似文献   

18.
Cheese were brined in a modified brine containing a mixture of sodium and potassium chlorides (1: 1.27, w/w), following technological instruction, for 24 hours and in a shortened time of 18 h and 12 h. Edam type cheese brined for 24 h in a traditional brine served as a control. In the ripening period, the cheeses were subjected to the following microbiological analyses: total bacteria count, the number of acidifying streptococci, the most probable number (MPN) of resting spores of anaerobic saccharolytic bacteria, the count of E. coli and the number of coagulase-positive staphylococci. The cheeses were additionally subjected to chemical analyses, including the determination of acidity, water content, salt content and a panel assessment of their organoleptic traits. The microbiological analysis demonstrated an increase in the total bacteria count and a decrease in the number of acidifying streptococci coinciding with the progress in ripening. No significant changes were observed in the population of microflora examined in the cheeses brined in the modified brine, as compared those produced in the traditional brine. The type of brine used also had no significant effect on changes in the MPN of resting spores of anaerobic saccharolytic bacteria. In none of the cheeses analyzed in this study was found E. coli bacteria or coagulase-positive staphylococci.  相似文献   

19.
Cancer pagurus is a widely appreciated crustacean in Southern European countries, where they have different market prices depending on the catching area and animal sex. Yet, the mineral composition of this species is still poorly understood. Therefore, the aim of this study was to quantify the content of essential elements in edible tissues of specimens from the Scottish Coast and English Channel and to compare such values with the Dietary Reference Intakes. Crabs caught off Scottish Coast had higher Na, Cl, K, Cu, Zn and Se content, while specimens harvested in the English Channel showed higher Mn concentrations. Females were better sources of Cu, Zn and Se, whereas males had higher concentrations of Na, Cl, K, Ca and Mn. Hepatopancreas showed higher contents of most elements, except Mn, Zn and Se than muscle and gonads. These results are certainly related to the crabs’ physiological needs and the bioavailability of the elements in water and diet. In general, C. pagurus is an excellent source of macro (Na, Cl and Ca) and trace elements (Fe, Cu, Zn and Se) for human consumption. The present study highlights the importance to take into consideration all edible tissues of crustaceans to evaluate their nutritional quality given consumers’ habits.  相似文献   

20.
Proximate composition, fatty acids and amino acid profiles and nutritional (chemical score, protein digestibility, PDCAAS and mineral dialyzability) and antioxidant properties (TEAC, DPPH and power reduction) from Porphyra columbina were evaluated. Total dietary fiber (48.02?±?1.13?g/100?g dry weight) and protein (24.61?±?0.21?g/100?g dry weight) were the two most abundant components in this seaweed. The main saturated and unsaturated fatty acids were C16:0 and C20:5 (n?3), respectively. The limiting amino acid was tryptophan with a chemical score of 57%. Protein digestibility was 74.33?±?3.0%. Porphyra columbina has high mineral content with good Na/K relationship and medium value of potential mineral accessibility (P, Ca and Zn dializability: 18.75?±?0.01, 17.62?±?0.16 and 16.70?±?0.44, respectively). The highest antioxidant properties were obtained with an acetone/water extraction system. This work provides important information about chemical composition and nutraceutical new properties of P. columbina.  相似文献   

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