鱼骨粉制备复合氨基酸螯合钙工艺研究

以鱼骨粉水解液为钙源,螯合率为指标,研究了复合氨基酸与鱼骨粉钙离子螯合条件.结果显示,鱼骨粉制备复合氨基酸螯合钙的最佳条件是:pH值为7,复合氨基酸与钙质量比为1:1,螯合时间为50 min,温度为70℃,产品螯合率为88.84%.最后通过比较螯合前后红外光谱图,证明氨基酸螯舍钙的形成.     

复合氨基酸螯合钙的合成工艺优化

以鱼类加工下脚料鱼头、鱼排为原料制备复合氨基酸螯合钙,采用Plackett-Burman设计、最陡爬坡试验和中心组合设计法对螯合工艺条件进行优化。结果表明,pH值和氨基态氮对螯合率有显著影响(P<0.05),复合氨基酸液中氨基酸的种类及其含量对螯合效果影响较大,当氨基酸浓度大于2.1mg/mL时,螯合钙中相应的氨基酸相对含量也较高;在复合氨基酸液与钙液螯合时,甲硫氨酸和甘氨酸对钙的螯合能力均大于丙氨酸。优化后的螯合工艺参数:pH值7.90,温度50℃,时间60min,氨基态氮浓度为3.66g/L,复合氨基酸液∶钙液(V∶V)20∶1,该条件下螯合率为58.19%。     

复合L-氨基酸螯合钙对大鼠骨密度增加的影响

研究复合L-氨基酸螯合钙对SD大鼠骨密度的影响.将SD大鼠随机分成6组,分别喂养复合L-氨基酸螯合钙,"乐力"氨基酸螯合钙和低钙饲料,通过测量相应饲料喂养大鼠身长、体重、钙表现吸收率,股骨长度、质量、骨密度和股钙含量等指标,观察复合L-氨基酸螯合钙对SD大鼠骨密度的影响.结果表明:2种剂量的复合L-氨基酸螯合钙和"乐力"氨基酸螯合钙对大鼠的身长和体重、股骨质量、骨密度、钙含量和钙表观吸收率显著高于低钙饲料组﹙P＜0.01﹚,两种剂量水平的氨基酸螯合钙对大鼠骨密度、股骨钙含量和钙表观吸收率差异显著﹙P＜0.01﹚,复合L-氨基酸螯合钙具有增加大鼠骨密度的功能.     

以贝壳粉为钙源的复合氨基酸螯合钙制备工艺优化

以废弃贝壳制得贝壳粉作为钙源,采用水体系合成法同时制备L-组氨酸和L-精氨酸复合氨基酸螯合钙,以螯合率为指标,设计单因素试验与正交试验,考察复合氨基酸与贝壳粉的摩尔比、pH值、反应温度、反应时间等因素对螯合率的影响。结果显示最佳螯合条件：复合氨基酸-贝壳粉摩尔比为1∶1,反应时间为60 min,反应温度为50℃,溶液pH值为9,在此条件下得到的复合氨基酸螯合钙螯合率最高。为废弃贝壳粉的高附加值利用和复合氨基酸螯合钙的制备工艺提供新思路。     

氨基酸螯合钙的研究进展

从制备氨基酸螯合钙的原料及氨基酸螯合钙的制备方法两方面进行综述,为更好的开发复合氨基酸螯合钙产品提供思路。     

罗非鱼骨粉制备氨基酸螯合钙及抗氧化性研究

利用罗非鱼鱼排、鱼头酶解获得鱼骨粉和复合氨基酸液,然后以罗非鱼骨粉的酸解液为钙源,与复合氨基酸液进行螯合反应制备氨基酸螯合钙,并对其抗氧化性进行研究。在单因素试验的基础上采用多元线性回归正交组合试验,以螯合率为指标,研究复合氨基酸液与罗非鱼骨粉的螯合条件。结果显示：pH7.0、反应时间90min、反应温度60℃、氨基态氮质量浓度1.6g/L,产品螯合率为57.22%。抗氧化研究结果表明,在一定的体积范围内,氨基酸螯合钙浓缩液的还原力随着其体积的增大而增大。氨基酸螯合钙浓缩液对羟自由基的清除率和对超氧阴离子自由基的抑制率分别为6.60% 和51.67%。     

复合氨基酸螯合钙的研究进展

复合氨基酸螯合钙是一种新型补钙制剂,因其稳定性好、易吸收、生物效价高、抗干扰性强,适口性好、环保等优势而备受关注,并在农业、食品、医疗及畜牧业中得到广泛应用。本文就复合氨基酸螯合钙的概念、结构、吸收机理,原料来源,制备方法及其在各领域的应用进行了综述;也对复合氨基酸螯合钙未来的发展及存在的一些潜在安全问题做了浅析。为今后复合氨基酸螯合钙产品的开发提供思路。     

复合氨基酸钙的制备工艺研究

以毛发中的角蛋白为复合氨基酸的来源,对复合氨基酸钙的合成工艺进行了初步探讨。在单因素试验的基础上,通过正交试验研究了p H、螯合温度、螯合时间以及氨基酸与钙的配位比对螯合反应的影响,确立了最佳的反应条件:反应液p H 9,反应温度40℃,反应时间60 min,复合氨基酸与钙的配位比2∶1。并用紫外光谱、红外光谱和差示热量扫描仪(DSC)鉴定了产品。     

花生粕制备复合氨基酸螯合锌的研究

以花生粕为原料制备复合氨基酸螯合锌,实现花生的深加工综合利用。先用复合氨基酸标准品与氯化锌螯合,探究最佳螯合工艺;以花生粕为原料制备复合氨基酸,再用最佳螯合工艺制备复合氨基酸螯合锌,对其进行红外光谱(IR)表征,用EDTA法测定螯合物中锌含量,进一步确定目标产物。结果表明:复合氨基酸与氯化锌螯合的最佳工艺条件为螯合温度40℃、螯合时间0. 5 h、体系pH 5、复合氨基酸与氯化锌的物质的量比2∶1,制备得到的复合氨基酸螯合锌的纯度较高,锌含量为29. 34%。     

蛋壳粉制备氨基酸螯合钙工艺优化

以禽蛋加工下脚料蛋壳为原料,通过酸水解制备可溶性钙,调节pH后与甘氨酸螯合制备氨基酸螯合钙。其具有良好的化学和生化稳定性,生物学效价高等特点,能达到既补充氨基酸又补充钙的双重功效。结果表明,蛋壳粉酸水解最佳工艺条件为:1.0g蛋壳粉加入10mL2mol/L的盐酸,在50℃下酸水解15min。此条件下,可溶性钙得率为387.0mg/g;氨基酸螯合钙的最佳工艺条件为:可溶性钙和甘氨酸摩尔比为1:6,在pH为4.8,60℃下螯合反应1.5h。此条件下,可溶性钙的螯合率高达89.32%。因此,以蛋壳为原料,经酸水解溶出可溶性钙再与甘氨酸螯合制备氨基酸螯合钙补钙制剂,为禽蛋加工废弃物的综合利用提供新途径。     

Technological,nutritional and sensorial characteristics of wheat bread fortified with calcium salts

The aim of this paper was to carry out a comprehensive study of wheat flour breads fortified with different sources of calcium, which includes: technological, nutritional and sensorial characteristics. Calcium salts (lactate: LA, carbonate: CA, and citrate: CI) at two fortification levels (20% and 50%) were analysed. Only the LA fortified breads were harder with lower specific volume and the LA 50% showed the higher chewiness value. The crust colour of the CI 50% breads presented the lower browning index. In vitro nutritional studies showed that calcium content on digest and dialysate was significantly higher in all fortified breads. The CI 20% and all the 50% fortifications showed a better contribution of bioaccessible calcium. Sensorial general quality was not significantly different between fortified and Control breads.     

Stability of calcium salts of phosphorylated sucrose in fluids of the digestive tract

Calcium salts of phosphorylated sucrose, in addition to having cariostatic properties, can serve as a source of calcium and phosphorus and partly satisfy the nutritional requirements of an organism. It has been proved that two such preparations, commercial Australian ‘Anticay’ and a Czech product, have similar properties. Calcium present in these preparations is dissociated partly in saliva and totally in gastric juice. Phosphorus is released only in the duodenum and small intestine. Calcium salts of phosphorylated sucrose are not hydrolysed by invertase.     

Effect of pH,Temperature and Reaction Time on Calcium Binding by Hydroxypropyl Rice Starches

Calcium binding by both native and hydroxypropyl starches was studied in aqueous media under different pH, temperature and reaction times at various calcium: starch ratios. Calcium binding was markedly influenced by pHs and temperatures of the reaction mixture. Reaction times did not show marked influence on calcium binding. Maximum calcium binding was observed in alkaline pH and at lower temperature. Most of the calcium bound within the first 20 minutes. Thus, alkaline pH and lower temperature is more favourable for calcium binding by both native and hydroxypropyl rice starches compared to acidic pH and higher temperatures.     

Calcium distribution in rat after per os administration of 45Ca-salts of phosphorylated sucrose

The incorporation of calcium from ⁴⁵Ca labelled calcium salts of phosphorylated sucrose and ⁴⁵CaCl₂ was compared in vivo. It is possible to assume that the incorporation of ⁴⁵Ca after per os application of ⁴⁵Ca-salts of phosphorylated sucrose is about 5–15% lower in comparison with ⁴⁵CaCl₂. This difference in calcium incorporation is explained by the presence of insoluble (and therefore unutilizable) ⁴⁵Ca₃(PO₄)₂ in the preparations of calcium salts of phosphorylated sucrose. The maximal incorporation of radioactivity can be found in bones 24–48 h after receipt, depending on the preparation applied. The rate of calcium incorporation into teeth is slower and the maximum is reached 72 h after per os application of any preparation tested. It was proved that calcium is transported from bones to teeth before its excretion from the organism. Calcium incorporation into organs is very low (about 3% of applied radioactivity). Almost all calcium incorporated in these tissues is excreted from the organism in the course of 3 days. The results indicate that calcium salts of phosphorylated sucrose could be used as a suitable support for calcium fortification in selected foodstuffs.     

Impact of source and level of calcium fortification on the heat stability of reconstituted skim milk powder

Calcium enrichment of food and dairy products has gained interest with the increased awareness about the importance of higher calcium intake. Calcium plays many important roles in the human body. Dairy products are an excellent source of dietary calcium, which can be further fortified with calcium salts to achieve higher calcium intake per serving. However, the addition of calcium salts can destabilize food systems unless conditions are carefully controlled. The effect of calcium fortification on the heat stability of reconstituted skim milk was evaluated, using reconstituted skim milks with 2 protein levels: 1.75 and 3.5% (wt/wt) prepared using low and high heat powders. Calcium carbonate, phosphate, lactate, and citrate were used for fortification at 0.15, 0.18, and 0.24% (wt/wt). Each sample was analyzed for solubility, heat stability, and pH. The addition of phosphate and lactate salts lowered the pH of milk, citrate did not have any major effect, and carbonate for the 1.75% protein samples increased the pH. In general, changes in solubility and heat stability were associated with changes in pH. Calcium addition decreased the solubility and heat stability. However, interestingly, the presence of carbonate salt greatly increased the heat stability for 1.75% protein samples. This is due to the neutralizing effect of calcium carbonate when it goes into solution. The results suggested that the heat stability of milk can be affected by the type of calcium salt used. This may be applied to the development of milk-based calcium enriched beverages.     

Calcium bioavailability in human milk,cow milk and infant formulas—comparison between dialysis and solubility methods

The percentages of total, soluble and dialysable calcium of human milk, cow milk and milk and soy based infant formulas were determined in order to detect possible differences in the calcium bioavailability of the samples. For this purpose an in vitro method was applied to these four calcium sources. The ranking of the analysed samples in terms of calcium bioavailability depends on the criteria applied. Calcium ranked dialysis percentage was: cow milk>human milk>soy based formula>milk based formulas. Calcium ranked solubility percentage was: human milk>cow milk>soy-based formula>milk-based formulas. Comparison of the results of the in vitro assay with the information available on in vivo calcium absorption showed that the total soluble calcium contents agree with the in vivo absorption values better than with calcium dialysis percentages.     

市售补钙制剂吸收率与生物利用率评价方法探讨

缺钙是全人类普遍关注的问题,选择有效补钙制剂是预防和治疗钙缺乏的重要手段。目前,市售补钙制剂品种繁多,良萎不齐,评价补钙制剂的方法也多种多样。补钙制剂大多为复合制剂,评价要从多方面综合评价。要合理评价补钙制剂,不仅要看钙的吸收情况,更重要的是钙的骨骼利用情况。因此,本文通过将补钙制剂的评价方法分为钙吸收评价方法和骨骼效应两种,分别综述了各种方法的优缺点。并提出用同位素标记体内钙库,结合骨组织形态学方法,为建立一个科学、准确、快速的补钙制剂生物利用率的评价体系提供新的思路。     

牦牛骨粉对大鼠骨钙、骨密度及骨钙吸收率影响的研究

目的:研究牦牛骨粉钙吸收率及对大鼠骨钙、骨密度的影响。方法:清洁级雌性SD大鼠,70只,随机分为7组,即低钙对照组(饲料中含钙量为1180mg/kg),牦牛骨粉高、中、低三个剂量组(相当于人体推荐摄入量的5、10、20倍),实测值饲料中含钙量为1437、1852、2778mg/kg,另设与样品对照组剂量相对应的三个碳酸钙对照组。于实验第4w末进行三天的钙代谢试验。整个喂养时间为12w,实验结束日,测右侧股骨长度,干重,骨钙含量及骨密度。结果:牦牛骨粉10、20倍剂量组股骨钙含量、股骨骨密度高于低钙对照组,5、20倍剂量组钙表观吸收率高于相应剂量的碳酸钙对照组(p<0.05)。结论:牦牛骨粉不仅有增加骨密度功能,并具有较高的钙表观吸收率。     

Influence of calcium on tensile, optical and water vapour permeability properties of sodium caseinate edible films

The influence of calcium on sodium caseinate edible films with and without lipid addition (oleic acid (OA)–beeswax (BW) mixtures) was investigated through the analysis of tensile, optical and water vapour barrier properties. Calcium was added by substitution of sodium caseinate by calcium caseinate. Calcium caseinate films have less transparency and more rigidity but they have lower water vapour permeability values than sodium caseinate films. The effect of substitution was different for films with and without lipids. Calcium caseinate increased tensile strength and decreased elongation of films, depending on the level of substitution and lipid presence. Among control films (without lipid), water vapour permeability was reduced when calcium caseinate was present, reaching values of 3.9 (±0.2) g mm kPa⁻¹ h⁻¹ m⁻². Nevertheless, in the films containing lipids, this reduction was inhibited when the level of sodium caseinate substitution exceeded 50%. Film transparency and gloss was reduced by calcium caseinate and lipid presence, although pure calcium caseinate films were glossier. When taking all the studied variables into account, the films prepared with 2:1 NaCas:CaCas ratio and 70:30 OA:BW ratio showed the most adequate properties.     

Calcium Bioavailability from High Oxalate Vegetables: Chinese Vegetables, Sweet Potatoes and Rhubarb

Absorption of calcium from high calcium vegetables endogenously labeled with ⁴⁵Ca was studied in premenopausal women using a randomized cross over design. Chinese (C.) vegetables are a major source calcium, but the bioavailability is unknown and likely affected by oxalic acid content. Calcium absorption from Chinese vegetables, sweet potatoes, and rhubarb, was compared to milk at the same calcium level for calculation of an absorption index. Calcium absorption generally reflected oxalic acid content. Calcium absorption index (X±SEM) was least for C. spinach (0.257±0.0228) and rhubarb (0.235±0.0233), intermediate for sweet potatoes (0.423±0.0255), and highest for C. mustard greens (1.097±0.0532) and C. cabbage flower leaves (1.097±0.0532).