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1.
Effects of microbial phytase on bioavailability of calcium added to corn/soy diets were investigated in chickens. No effect (P > 0.17) of phytase was found for weight gain, feed intake, tibia/body weight, ash%, and ash Ca% when calcium citrate malate (CCM) was added to corn/soybean meal and corn/hydrothermally cooked (HTC) soymilk diets. Using calcium carbonate in corn/HTC soymilk diets, means for weight gain, feed intake, tibia/body weight, and ash% were less (P < 0.05) without phytase. We hypothesize that CCM is less amenable to the formation of calcium phytate complexes than are other calcium salts and, therefore, should be more effective for fortification of soymilk products.  相似文献   

2.
The nutritional value of five samples of black cumin seeds from five different sources available in the local market were studied. The average values of the proximate analysis on dry matter basis were 216 g kg−1 for crude protein, 406 g fat, 45 g ash, 84 g crude fibre and 249 g of nitrogen-free extract, whereas moisture content was 38 g kg−1. The mineral and vitamin analyses showed that black cumin seeds contained iron, (105 mg kg−1) copper (18 mg), zinc (60 mg) phosphorus (527 mg), calcium (1860 mg), thiamin (15·4 mg), niacin (57 mg), pyridoxine (5·0 mg) and folic acid (160 μg). The protein quality of black cumin seeds was evaluated using net protein utilisation (NPU), protein efficiency ratio (PER) and net dietary protein energy percent (NDPE %) for two samples imported from Syria and Turkey, while PER was determined for the Syrian sample only. The results indicated that the NPU standardised of Turkish black cumin seeds was significantly higher than that of Syrian type (P<0·05). The mean results (±SD) were 54·6±2·72 for the Syrian type and 63·1±3·74 for the Turkish type. The NDPE% mean results (±SD) were 5·3±0·79 and 5·6±0·26 for the Syrian and the Turkish samples, respectively. The PER adjusted value for the Syrian samples was 1·9. The results of protein quality evaluation and those of the nutrient composition suggest that black cumin is of relatively good nutritional value. © 1998 SCI.  相似文献   

3.
目的评定电感耦合等离子体质谱法(ICP-MS)测定保健食品中锰、铁、锌、硒矿物元素的不确定度。方法根据JJF1059.1-2012《测量不确定度评定与表示》,分析测量不确定度分量的主要来源,对各不确定度分量进行评定和计算。结果在P=95%,k=2时,保健食品中锰、铁、锌、硒的含量分别为(23.8±1.8)、(102.0±8.4)、(21.0±1.8)和(0.0936±0.0092) mg/kg。通过对不确定度的来源分析及各分量的量化评定,标准曲线拟合引入的不确定度最大,其次是回收率、定容体积引入的不确定度分量。结论该研究可为实验室评定保健食品中锰、铁、锌、硒的测定结果质量提供参考。  相似文献   

4.
Scope Xanthohumol (XN), a dietary flavonoid found in hops, may have health‐protective actions against cardiovascular disease and type 2 diabetes. Yet, there are limited data on the pharmacokinetics (PK) of XN. This study provides PK parameters for XN and its major metabolites in rats. Methods and results A PK study was conducted in male jugular vein‐cannulated Sprague‐Dawley rats. Rats (n = 12/group) received an intravenous (IV) injection (1.86 mg/kg BW) or an oral gavage of a low (1.86 mg/kg BW), medium (5.64 mg/kg BW), or high (16.9 mg/kg BW) dose of XN. Plasma samples were analyzed for XN and its metabolites using LC‐MS/MS. The maximum concentration (Cmax) and area under the curve (AUC0‐96 h) of total XN (free and conjugated) were 2.9±0.1 mg/L and 2.5±0.3 h* mg/L in IV group, 0.019±0.002 mg/L and 0.84±0.17 h* mg/L in the oral low group, 0.043±0.002 mg/L and 1.03±0.12 h* mg/L in the oral medium group, and 0.15±0.01 mg/L and 2.49±0.10 h* mg/L in the oral high group. Conclusion The bioavailability of XN is dose‐dependent and approximately 0.33, 0.13, and 0.11 in rats, for the low‐, medium‐, and high‐dose groups, respectively.  相似文献   

5.
The utility of the phytate/zinc and phytate × calcium/zinc molar ratios for predicting zinc bioavailability from processed soybean foods was investigated. Weight gain and bone zinc accumulation in rats fed various soy protein products were plotted against the calculated molar ratios. The phytate × calcium/zinc ratio was a better predictor of zinc bioavailability in similarly processed products than was the phytate/ zinc ratio. However, in some cases the phytate × calcium/zinc ratio was not effective since some processing procedures apparently altered binding of phytic acid to minerals and other food components.  相似文献   

6.
The chemical composition and protein quality of the kernels from Lupinus angustifolius seeds were compared with that for sprouts after 6 days germination. Germination resulted in an apparent increase in protein content from 395 g kg?1 to 435 g kg?1 DM. Fat and carbohydrate contents decreased. The oligosaccharide content of the sprouted lupin fell to a negligible level, while the phytate and alkaloid concentrations fell from 4.7 g kg?1 to 1.6 g kg?1 and from 0.72 g kg?1 to 0.16 g kg?1, respectively. The quality of lupin kernel protein was poor with a protein efficiency ratio (PER) of 1.45±0.15. Supplementation of kernel with DL-methionine (2.0 g kg?1) increased the protein quality (PER = 2.87±0.17) to that of casein (PER = 2.86±0.18). Germination reduced protein quality (PER = 0.44±0.16), and did not improve apparent protein digestibility (APD kernel = 80.4%; APD sprout = 77.5%). Supplementation of sprout protein with DL-methionine (2.0 g kg?1) increased the protein quality (PER = 2.57±0.20). The total sulphur-containing amino acid concentration of lupin kernel protein, 1.9 g per 16 g N was low, and decreased further to 1.3 g per 16 g N in the sprout, a drop of 32%. The results showed that germination of lupin seeds reduced the concentration of the anti-nutritive factors; however, it also reduced protein quality.  相似文献   

7.
Fourteen entire-male pigs of 16 kg mean liveweight were given a synthetic diet, the sole protein source of which comprised enzymically hydrolysed casein and free synthetic amino acids. The amino acid balance of the 80 g kg?1 crude protein diet was formulated to equal the Agricultural Research Council (1981) recommended ideal amino acid balance for the growing pig (20 to 90 kg liveweight). In two separate metabolism trials the biological value (BV) of the diet was estimated to be 0.86±0.012 (n=8) and 0.82±0.025 (n=5), respectively. Both BVs were significantly lower than unity, indicating that this dietary amino acid balance was less than ideal for the young pig.  相似文献   

8.
金属盐对清料法腌制皮蛋品质的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
以鸭蛋为原料,通过比较不同金属盐清料法加工的皮蛋的安全性能和感官性质,研究了金属盐的种类和添加量对皮蛋品质的影响。试验结果表明:分别添加了Cu SO4、Cu SO4:Zn SO4=1:1和Zn SO4:Fe SO4=1:1腌制的皮蛋的感官品质都较好,评分分别为90.60±2.40、89.80±3.20、88.20±2.70;添加了Zn SO4溶液次之,感官评分为85.80±3.80;单独添加Fe SO4、Mg SO4盐腌制的皮蛋感官品质比较低;添加Cu SO4:Zn SO4=1:1的溶液腌制的皮蛋,锌铜的残留量(铜离子4.12±0.11 mg/kg,锌离子8.32±0.19 mg/kg)比显著低于分别添加锌盐(12.96±0.22 mg/kg)和铜盐(铜离子8.55±0.28 mg/kg)的低皮蛋(P0.05);不同锌盐对皮蛋感官品质的影响有区别,用氧化锌生产的皮蛋锌的残留量(9.27±0.09 mg/kg)和感官评分显著低于其他锌盐腌制的皮蛋,综合考虑,Zn SO4是腌制皮蛋较适合的锌盐;添加Cu SO4或Cu SO4:Zn SO4=1:1生产的皮蛋,蛋黄的溏心指数较高(0.66、0.57),皮蛋的弹性、硬度、咀嚼度较好,因此,从感官品质和金属的残留量两方面考虑,用Cu SO4和Zn SO4混合清料法腌制皮蛋比较好,而单独添加Fe SO4生产皮蛋明显不适合。  相似文献   

9.
Plant‐based diets contain less saturated fat and cholesterol and more folate, fibre and phytochemicals than omnivorous diets, but some micronutrients, especially zinc, are poorly bioavailable. The findings of studies exploring the zinc intake and zinc status in populations that habitually consume vegetarian diets are inconsistent. This study aims to investigate the effects of plant‐based diets on dietary zinc intake and status in humans using systematic review and meta‐analysis techniques. Thirty‐four studies were included in the systematic review. Of these, 26 studies (reporting 48 comparisons) compared males and/or females consuming vegetarian diets with non‐vegetarian groups and were included in meta‐analyses. Dietary zinc intakes and serum zinc concentrations were significantly lower (?0.88 ± 0.15 mg day?1, P < 0.001 and ?0.93 ± 0.27 µmol L?1, P = 0.001 respectively; mean ± standard error) in populations that followed habitual vegetarian diets compared with non‐vegetarians. Secondary analyses showed greater impact of vegetarian diets on the zinc intake and status of females, vegetarians from developing countries and vegans. Populations that habitually consume vegetarian diets have low zinc intakes and status. Not all vegetarian categories impact zinc status to the same extent, but a lack of consistency in defining vegetarian diets for research purposes makes dietary assessment difficult. Dietary practices that increase zinc bioavailability, the consumption of foods fortified with zinc or low‐dose supplementation are strategies that should be considered for improving the zinc status of vegetarians with low zinc intakes or serum zinc concentrations at the lower end of the reference range. © 2013 Society of Chemical Industry  相似文献   

10.
Protein sources studied were oat groats, oat crude protein extracted at pH 9.5 (PE) and oat protein concentrate obtained by isoelectric precipitation (PC) of the alkaline extract. PER of Scott proteins was higher than that of corresponding Hinoat proteins: 2.31 ± 0.17 vs 2.15 ± 0.12 for groats, 2.08 ± 0.13 vs 1.93 ± 0.11 for PE and 2.11 ± 0.12 vs 1.97 ± 0.06 for PC. However, for both cultivars, PERs of PC and PE were lower than PER for groats. There was no difference between NPR of Scott and Hinoat for the same protein fractions. Apparent digestibility coefficient (ADC) of Scott proteins were lower than the corresponding Hinoat proteins, and for both cultivars protein ADCs were in the following order: PC > PE > groats.  相似文献   

11.
Zinc bioavailability was studied in five cultivars of beans (Phaseolus vulgaris, L): white (Ouro Branco), black (Diamante Negro), and brown (BRS Radiante, Pérola and Talismã) cooked with or without soaking water. The cooked bean flours or ZnCO3 were added to the test or control diets to provide 15 mg Zn/kg diet and were fed to weaning Wistar male rats for 42 days. Blood and femur were collected for analyses of plasma and erythrocyte Zn, bone weight and bone/dietary mineral ratio. Zinc bioavailability of Ouro Branco bean cooked with soaking water was higher than the other cultivars and similar to the control diet. Talismã without soaking water showed the lowest values for most of the parameters analyzed. Zinc bioavailability was not affected neither by the cooking process itself nor by the contents of phytate, tannins and dietary fiber, but it varied according to the bean cultivar and the phytate × calcium:zinc molar ratio.  相似文献   

12.
《Food chemistry》2001,72(1):89-95
Concentrations of copper and zinc were determined in 80 Nigerian food items of various classes which were obtained from the markets of Ibadan city. These consisted of leafy and fruity vegetables, tubers, fruits, meats, fish, legumes, cereals, spices, dairy products, sweeteners, fats and oils, confectioneries, canned foods and alcoholic beverages. Copper levels ranged widely from 0.06 to 13.3 mg/kg, while zinc levels ranged from 0.06 to 56.9 mg/kg in various foods. The differences in mean metal levels were found to be significant (P=0.05) among the various food classes. Highest levels of both metals were found to occur in legumes (Cu, 8.3±3.7 mg/kg; Zn, 29±12 mg/kg). The levels of the metals compare well with those which have been obtained in foods from studies elsewhere in the world. The dietary intakes of both metals for the adult population was found to vary with the income groups, with higher intakes being estimated for higher income groups. The estimated weighted average dietary intakes for the entire adult population were calculated to be 2.64 mg Cu/day and 15.8 mg Zn/day.  相似文献   

13.
摘 要: 目的 对大米、玉米和辣椒中钙含量进行测定, 探究钙的生物可给性差异及其膳食营养价值。方法 采用分层随机抽样方法, 样本来自贵州省的9个市州。基于火焰原子吸收光谱法测定大米、玉米和辣椒钙含量, 通过体外消化模型(in vitro digestion mode)模拟胃部及肠道消化, 计算大米、玉米和辣椒中钙的生物可给性。结果 辣椒钙含量最高, 为(1799.50±398.70) mg/kg, 其次为玉米, 为(253.41±103.37) mg/kg, 大米最低, 为(69.90±20.53) mg/kg, 3组钙含量差异有统计学意义(F=5249.93, P<0.001)。通过体外消化模型得出大米、玉米和辣椒在胃阶段钙的生物可给性均高于肠阶段(P<0.001); 进一步分析发现, 大米在胃阶段钙的生物可给性(69.72%±10.31%)>玉米(41.40%±11.37%)>辣椒(35.31%±5.46%), 差异有统计学意义(F=192.67, P<0.001); 大米在肠阶段钙的生物可给性(56.69%±12.78%)>辣椒(23.29%±7.66%)>玉米(14.51%±5.19%), 差异有统计学意义(F=294.73, P<0.001)。结论 研究发现大米、玉米和辣椒中钙的膳食营养价值均有限, 不是居民良好的膳食钙来源, 因此, 有必要开展相关的营养教育和干预, 改善居民的饮食结构, 增加牛奶和乳制品的摄入量, 以减少膳食钙摄入量的不足。本研究可为我国居民建立合理饮食结构提供科学依据。  相似文献   

14.
In the current study, we used heat stress (HS) as an oxidative stress model to examine the effects of hydroxy-selenomethionine (HMSeBA), an organic selenium source, on selenium's bioavailability, antioxidant status, and performance when fed to dairy cows. Eight mid-lactation Holstein dairy cows (141 ± 27 d in milk, 35.3 ± 2.8 kg of milk/d, parity 2 or 3) were individually housed in environmental chambers and randomly assigned to 1 of 2 treatments: inorganic Se supplementation (sodium selenite; SS; 0.3 mg of Se/kg of dry matter; n = 4) or HMSeBA supplementation (0.3 mg of Se/kg of dry matter; n = 4). The trial was divided into 3 continuous periods: a covariate period (9 d), a thermal neutral (TN) period (28 d), and a HS period (9 d). During the covariate and TN periods, all cows were housed in TN conditions (20°C, 55% humidity). During HS, all cows were exposed to cyclical HS conditions (32–36°C, 40% humidity). All cows were fed SS during the covariate period, and dietary treatments were implemented during the TN and HS periods. During HS, cows fed HMSeBA had increased Se concentrations in serum and milk, and total Se milk-to-serum concentration ratio compared with SS controls. Superoxide dismutase activity did not differ between Se sources, but we noted a treatment by day interaction in glutathione peroxidase activity as HS progressively reduced it in SS controls, whereas it was maintained in HMSeBA cows. Supplementation with HMSeBA increased total antioxidant capacity and decreased malondialdehyde, hydrogen peroxide, and nitric oxide serum concentrations compared with SS-fed controls. We found no treatment effects on rectal temperature, respiratory rate, or dry matter intake. Supplementing HMSeBA tended to increase milk yield and decrease milk fat percentage. No other milk composition parameters differed between treatments. We observed no treatment effects detected on blood biochemistry, except for a lower alanine aminotransferase activity in HMSeBA-fed cows. These results demonstrate that HMSeBA supplementation decreases some parameters of HS-induced oxidative stress.  相似文献   

15.
The effect of flour extraction rate, type and length of fermentation and baking conditions on relative bioavailability of zinc of five distinctly different Iranian flat breads and their unfermented doughs, was determined using weanling rats fed low (5.5 ppm) levels of dietary zinc. When breads rather than unfermented doughs were used for preparation of diets, with one exception, bioavailability of Zn significantly (P < 0.05) improved. Rats on the barbari-bread-based diet showed the highest weight gain and femur zinc content. There was no significant difference in weight gain among rats on dough-based diets. High correlation of weight gain and femur zinc with feed intake and low or no correlation with fiber or Zn:phytate molar ratio of the diets was observed.  相似文献   

16.
Five distiller's spent grain (DSG) samples were analyzed for their compositional and nutritional (protein efficiency ratio, PER) values. The protein content (N × 6.25) of these samples ranged from 26.9–34.9% (air-dry basis). True protein content, however, was substantially lower. Dietary fiber content of samples ranged from 29.1–35.8%. Samples contained about 3% nucleic acid. All samples contained appreciable amounts of potassium, magnesium, phosphorus, zinc, copper, iron, chromium, thiamin, riboflavin and niacin. The lysine content of DSG samples ranged from 2.50–3.74 g/100g protein. Except for one sample (PER, 1.7), the quality of protein in the samples was low (PER, 0.6 ± 0.1).  相似文献   

17.
目的评定采用电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)检测扇贝中铅、砷、镉含量的不确定度。方法分析整个测量过程中存在的不确定度因素,包括测量重复性、称样量、稀释体积、标准溶液、标准曲线拟合以及方法回收率等,建立数学模型,对测量结果的不确定度进行评定。结果影响测量结果的不确定度主要来源于测量重复性、样品前处理和标准曲线拟合。扇贝样品中结果表示分别为:铅含量(1.82±0.33)mg/kg;砷含量为(3.43±0.35)mg/kg;镉含量为(1.32±0.17)mg/kg,k=2。结论该方法准确度高,适用于扇贝中重金属元素的检测,为提高数据准确性提供有效指导。  相似文献   

18.
Hard-to-cook (HTC) defect was induced in cowpea seeds by storing at 37°C and 85% relative humidity (RH) for 6 wk. HTC and control (stored at 7°C, 60% RH) seeds were boiled for 45 and 90 min or ground to flour. Flour was cooked as paste or extruded (20% H2O, 150°C). Overall dietary quality was estimated as Feed Efficiency and Relative Response Ratio. Protein quality was determined as Nitrogen Efficiency and Relative Nutritive Value. Overall and protein nutritional quality were generally higher for control than for HTC cowpea diets. Processing affected control and HTC seeds differently. Boiling either control or HTC whole seeds improved both overall and protein quality compared to raw seeds, while extrusion substantially increased the quality of control seeds but reduced the quality of HTC seeds. Cooking as paste improved protein and overall quality of control seeds but not protein quality of HTC seeds.  相似文献   

19.
There is a high prevalence of iron deficiency anaemia in many developing countries today; especially in vegetarian women. The major cause of this state is low bioavailability of nonheme iron from vegetarian diets. An investigation was undertaken to improve bioavailable contents of nonheme iron from vegetarian meals. Forty-eight meals with combinations of roti (unleavened whole cereal pancake) of one of the six cereals and one of the four commonly consumed green leafy vegetables (GLV) along with 35 meals with cereal roti and fruit vegetable/legume were tested for their in vitro dialysability of iron using simulated gastrointestinal conditions and standardised protocol with 59Fe as a tracer. Average bioavailable iron density of GLV-based meals was significantly higher (1.2±0.7 mg /1000 kcal) as against the value in prevailing dietary patterns having cereal-legume or cereal-fruit vegetable combinations (0.36±0.17 mg/1000 kcal, p⩽0.001). Around 31 GLV-based meals were identified as having higher amounts of bioavailable iron density than 0.75 mg/1000 kcal. Thus, one such GLV-based meal per day will increase gross as well as bioavailable iron intake which will help in meeting daily requirements of iron especially for vegetarian women of reproductive age.  相似文献   

20.
3-Nitrooxypropanol (NOP) is a promising methane (CH4) inhibitor. Recent studies have shown major reductions in CH4 emissions from beef and dairy cattle when using NOP but with large variation in response. The objective of this study was to quantitatively evaluate the factors that explain heterogeneity in response to NOP using meta-analytical approaches. Data from 11 experiments and 38 treatment means were used. Factors considered were cattle type (dairy or beef), measurement technique (GreenFeed technique, C-Lock Inc., Rapid City, SD; sulfur hexafluoride tracer technique; and respiration chamber technique), dry matter (DM) intake, body weight, NOP dose, roughage proportion, dietary crude protein content, and dietary neutral detergent fiber (NDF) content. The mean difference (MD) in CH4 production (g/d) and CH4 yield (g/kg of DM intake) was calculated by subtracting the mean of CH4 emission for the control group from that of the NOP-supplemented group. Forest plots of standardized MD indicated variable effect sizes of NOP across studies. Compared with beef cattle, dairy cattle had a much larger feed intake (22.3 ± 4.13 vs. 7.3 ± 0.97 kg of DM/d; mean ± standard deviation) and CH4 production (351 ± 94.1 vs. 124 ± 44.8 g/d). Therefore, in further analyses across dairy and beef cattle studies, MD was expressed as a proportion (%) of observed control mean. The final mixed-effect model for relative MD in CH4 production included cattle type, NOP dose, and NDF content. When adjusted for NOP dose and NDF content, the CH4-mitigating effect of NOP was less in beef cattle (?22.2 ± 3.33%) than in dairy cattle (?39.0 ± 5.40%). An increase of 10 mg/kg of DM in NOP dose from its mean (123 mg/kg of DM) enhanced the NOP effect on CH4 production decline by 2.56 ± 0.550%. However, a greater dietary NDF content impaired the NOP effect on CH4 production by 1.64 ± 0.330% per 10 g/kg DM increase in NDF content from its mean (331 g of NDF/kg of DM). The factors included in the final mixed-effect model for CH4 yield were ?17.1 ± 4.23% (beef cattle) and ?38.8 ± 5.49% (dairy cattle), ?2.48 ± 0.734% per 10 mg/kg DM increase in NOP dose from its mean, and 1.52 ± 0.406% per 10 g/kg DM increase in NDF content from its mean. In conclusion, the present meta-analysis indicates that a greater NOP dose enhances the NOP effect on CH4 emission, whereas an increased dietary fiber content decreases its effect. 3-Nitrooxypropanol has stronger antimethanogenic effects in dairy cattle than in beef cattle.  相似文献   

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