柠檬酸-苹果酸复合钙盐的研究

目的研制柠檬酸-苹果酸复合钙盐新型钙营养强化剂。方法柠檬酸、苹果酸配成水溶液,定量分批均匀缓慢加入到碳酸钙乳液中,在特定温度下反应2次,冷冻结晶,干燥机烘干,制成柠檬酸-苹果酸复合钙盐钙营养强化剂。结果最佳生产参数为,反应温度40℃,摩尔比按钙(Ca)∶柠檬酸(CA)∶苹果酸(MA)=12∶6∶9,冷冻结晶2d,-18℃下冻干,自然温度下溶解,pH值为4。结论以上述工艺条件制作的柠檬酸-苹果酸复合钙盐,溶解度高,安全性好,为较理想的新型钙营养强化剂,值得推广。     

果酸钙的生理作用研究进展

果酸钙是一种新型的钙营养添加剂,由钙、柠檬酸和苹果酸按一定比例反应生成,具有高溶解性、高吸收利用性、安全无毒等特点。同其他钙营养强化剂相比,果酸钙既具有补充钙元素、增强骨密度、调节血脂等作用,又具有增强口腔健康、减少肾结石发生的风险、不影响其他微量元素吸收等生理作用。果酸钙又具备L-苹果酸抗疲劳、保护心脏等生理功能,可以作为食品添加剂,也可直接制成补钙保健食品,具有广泛的开发应用前景。本文就国内外果酸钙在生理作用方面的研究进行综述,以期为果酸钙的研究和应用提供新思路和方向。     

罗非鱼鱼鳞柠檬酸-苹果酸钙的制备及产物鉴定

以罗非鱼鱼鳞为原料,采用超声辅助复合有机酸制备柠檬酸-苹果酸钙（calcium citrate malate,CCM）,研究鱼鳞预处理方法、超声辅助酸制备工艺条件,并对产物进行表征。结果显示,鱼鳞无需熬煮,直接采用超声辅助提取效果理想;在液料比为20∶1（mL/g）条件下,正交试验优化得到复合钙最佳制备工艺条件为：柠檬酸和苹果酸总质量分数12%、二者质量比2∶1、超声温度70 ℃、超声时间1.0 h;在此条件下,得钙率为18.97%;红外光谱及X射线衍射分析均显示制备产物不是柠檬酸钙与苹果酸钙的简单混合物,而与CCM结构吻合;扫描电镜观察到产物结晶呈六方形;晶体比表面积介孔测定知罗非鱼鱼鳞复合钙产物孔径为4.049 nm,单点吸附总孔体积为0.320 cm3/g,T-图法微孔（外）比表面积为385.703 m2/g。本方法成功制备了罗非鱼鱼鳞CCM复合盐,得钙率较高,研究结果可为罗非鱼鱼鳞加工有机钙产品提供一定理论支持。     

补钙与钙营养强化剂CCM

阐述了钙在人体中的重要作用与补钙的必要性以及选择钙营养强化剂应考虑的原则,介绍了CCM作为钙营养强化剂的优良特性。     

微生态补钙制剂的生物利用研究

补钙制剂的生物利用率是评价补钙效果的重要指标。以KM种健康小鼠为模型,饲喂不同钙源及钙含量的饲料,测定饲料消耗量、粪钙、尿钙、骨钙和血钙,计算钙的表观吸收率及存留率,并与对应剂量的碳酸钙组对比,评价微生态补钙制剂的生物利用情况。结果表明：微生态补钙制剂低剂量组和标准剂量组的骨钙含量与相同水平的碳酸钙对照组比较差异显著(P＜0.05),钙的表观吸收率明显高于对应碳酸钙剂量组(P＜0.01);微生态补钙制剂组与碳酸钙对照组相比,血钙水平差异不显著(P＞0.05),但均高于碳酸钙对照组。表明微生态补钙制剂生物利用率高,是一种理想的补钙制剂。     

果酸钙的研制及其在高钙乳中的应用

研究了投料摩尔比、投料顺序、加水量及反应温度对制备果酸钙溶解度的影响,确定其最佳合成工艺为:碳酸钙、柠檬酸、苹果酸的摩尔比为8∶2∶5,反应温度为50℃,投料顺序为将碳酸钙粉加入到柠檬酸和苹果酸的混合溶液中,加水量为反应原料质量总和的4倍。用该方法合成的果酸钙在水中的溶解度为0·94mg/mL。另外对果酸钙在高钙乳中的应用做了简单的介绍。     

不同钙补充剂对体外胃酸消耗及大鼠胃液分泌的影响

比较柠檬酸苹果酸钙、碳酸钙、牦牛骨粉、L-天门冬氨酸钙这四种钙补充剂溶解后对胃酸的消耗情况,及对大鼠胃液分泌的影响,为消费者选择合适的钙剂提供参考。通过体外模拟人工胃环境,测定四种钙剂在人工胃液中释放钙离子所消耗的胃酸量;使用大鼠幽门结扎法建立大鼠胃液分泌模型,观察不同钙剂对大鼠胃液量、胃酸酸度及胃酸分泌量的影响。实验表明柠檬酸苹果酸钙溶解后使人工胃液中氢离子含量显著增加(P0.01),碳酸钙、牦牛骨粉和L-天门冬氨酸钙溶解后则使人工胃液中氢离子含量显著降低(P0.05);大鼠体内实验中,柠檬酸苹果酸钙组和牦牛骨粉组大鼠的胃液量、胃酸酸度及胃酸分泌量均显著减少(P0.01),L-天门冬氨酸钙组大鼠的胃液量、胃酸酸度及胃酸分泌量均显著增多(P0.01),碳酸钙组大鼠的胃液量、胃酸酸度、胃酸分泌量与正常对照组大鼠相比无显著性差异(P0.05)。     

无腥味大豆中加入胡萝卜汁生产豆奶的工艺研究

试验用无腥味大豆、胡萝卜汁为主要原料生产蔬菜汁豆奶。研究了糖、酸、防腐剂、胡萝卜汁用量、Ca2 浓度和植物油等原辅材料对制品稳定性的影响。采用强制分层法观察豆乳的稳定性。结果表明,控制干豆和水的配比为1∶14,加入8%~10%的蔗糖,0.05%的柠檬酸,20%胡萝卜汁,葡萄糖酸钙不超过277.8mg/100mL(Ca2 25mg),山梨酸钾0.01%~0.02%,0.8%植物油,制得口味好、营养丰富、稳定性高的胡萝卜汁无腥大豆豆奶。     

Calcium Bioavailability of Nanonized Pearl Powder for Adults

ABSTRACT: The present study was aimed to evaluate the calcium bioavailability of pearl powder for humans. Both the nanonized pearl powder (NPP) and the micronized pearl powder (MPP) prepared by a dry grinder were tested. A group of healthy adults free from hyperthyroidism, hypercalcemia, and hypocalcemia were recruited as the subjects for oral administration with the pearl powder. The bioavailability was evaluated by the serum total calcium increment, the serum intact parathyroid hormone (iPTH) reduction, and the urine calcium/creatinine ratio increment in 6 h after administration. The results show better absorption and retention of calcium from NPP, as reflected with the shorter time elapsed before the maximum concentration of calcium appeared in the serum, higher iPTH reduction, more calcium absorption, and higher maximum calcium concentration (C_max) in serum after ingestion, than that from MPP. We conclude that pearl powder is a beneficial source of calcium for adults and that nanonization improves its calcium bioavailability.     

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).     

Bioavailability of Calcium from Tofu as Compared with Milk in Premenopausal Women

ABSTRACT: Using a cross-over design, two studies were conducted to measure calcium absorption from calcium-set tofu compared to milk in healthy, premenopausal women. In "study 1," calcium absorption from tofu set with CaCl₂ was determined in Caucasian women by fecal recovery of the stable isotope, 44Ca. In "study 2," calcium absorption was determined in Asian women from tofu set with CaSO₄ by appearance of 45Ca in serum after 5 h. Analysis of the studies, both separately and pooled, showed that calcium absorption was similar between calcium-set tofu and milk. Calcium-set tofu is a concentrated source of bioavailable calcium.     

Production of Kefir from Soymilk With or Without Added Glucose, Lactose, or Sucrose

ABSTRACT: The effects of added glucose, lactose, and sucrose on microbial growth, acid, and ethanol production, and galactosidase activity in soymilk fermented with kefir grains were studied. Immediately after the addition of kefir grains to soymilk, the lactic-acid bacterial counts were higher, but the yeast counts were lower than in milk kefir. After fermentation for 32 h, the concentrations of yeast, lactic acid, and ethanol in soymilk were significantly lower than those in milk kefir. Addition of 1% glucose to soymilk stimulated growth of lactic-acid bacteria and yeast, the production of lactic acid and ethanol, and the β-galactosidase activity. Nevertheless α- galactosidase activity was suppressed by 1% glucose.     

超声波法制备蛋壳柠檬酸钙的工艺研究

为充分利用鸡蛋壳丰富的钙资源,通过单因素与三元正交多项式回归设计相结合的研究方法,构建出超声波法高效制备蛋壳柠檬酸钙的三元正交多项式回归模型,并优化出最佳工艺条件为：蛋壳粉颗粒细度180 目、料液比1:60、超声功率700W、超声时间25min、柠檬酸与蛋壳粉的质量比2:1、柠檬酸钙得率可达90.83%。超声波法与传统方法相比,不但提高了蛋壳柠檬酸钙产品得率,而且还克服了柠檬酸钙在制备过程中的凝聚沉淀现象。     

两种市售补钙制剂对生长期大鼠生物利用率的研究

市售补钙制剂种类繁多,良萎不齐,各种评价方法评价结果不尽一致,本文采用该吸收平台效应下剂量为实验剂量,利用表观吸收率等指标有效检验了两种市售复合补钙制剂.本文以生长期Wister大鼠为模型,用原子吸收测量了钙平衡后钙及其他元素的吸收率,并测量了股骨骨密度.结果显示在相同钙摄入量下,碳酸钙制剂吸收率低于氨基酸螯合钙（p＜0.05）,Zn、Mg、Pb的吸收量及吸收率均高于碳酸钙组（p＜0.01或p＜0.05）,骨密度两组差异没有统计学意义.由此可见复合氨基酸螯合钙制剂钙生物利用率优于复合碳酸钙制剂,但其重金属和微量元素也有较高的吸收率.     

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。     

罗非鱼骨制备CMC活性钙的工艺及生物利用的研究

为了充分利用罗非鱼骨这一丰富的钙源，本文采用柠檬酸和苹果酸混合酸对罗非鱼骨粉进行CMC钙的制备工艺研究，并以Wistar大白鼠为模型，评价该产品的生物利用率。结果表明：以柠檬酸和苹果酸按3：2的浓度比混合，在121℃的高温下提取罗非鱼骨粉1h，取上清液调pH中性，然后进行浓缩烘干，钙提取率为92．1％，产品在热水中溶解度达88％。动物代谢实验显示，与实验对照组比较，CMC活性钙组无论是在血钙、骨钙和存留率方面均有不同程度的增加，比碳酸钙更易被机体吸收利用。     

不同钙补充剂对缺铁性贫血大鼠钙、铁吸收的影响

探讨柠檬酸苹果酸钙(Calcium citrate malate,CCM)、碳酸钙(Calcium carbonate,Ca CO3)、骨钙(Bone calcium,BC)三种常用钙剂与富马酸亚铁(Ferrous fumarate,FF)合用对钙、铁吸收的影响,以及三种钙剂的生物利用度,为消费者选择合适的钙剂提供实验依据。建立大鼠缺铁性贫血模型,通过检测大鼠血红蛋白(Hemoglobin,Hb)和血清铁(Serum iron concentration,SFe)含量,观察三种钙源与铁制剂合用对钙、铁吸收的影响;通过药代动力学考察血清降钙素(Calcitonin,CT)含量,评估三种钙剂的生物利用度。实验结果表明CCM/FF组与Ca CO3/FF组和BC/FF组相比,CCM/FF组合给药3 d后即能显著升高缺铁性贫血大鼠血红蛋白含量,其血红蛋白含量给药14 d极显著高于Ca CO3/FF组(p<0.01);CCM/FF组的血清铁含量在给药1 d后即显著高于Ca CO3/FF组(p<0.01),说明CCM对铁吸收的抑制作用较小。此外,CCM的降钙素曲线下面积(Area under the curve,AUC)高于Ca CO3及BC,间接反映了CCM吸收率较其它钙剂多。      

Trypsin Inhibitor Activity and Tannin Content Do Not Affect Calcium Bioavailability of Three Commonly Consumed Legumes

Calcium bioavailability from legumes containing a range in trypsin inhibitor activity (TIA) and tannin concentration was studied. Three cultivars (Phaseolus vulgaris) were hydroponically grown and intrinsically labeled with ^4SCa. Raw and cooked legumes were fed to six groups of 6-wk old male Sprague-Dawley rats. Another group received an intraperitoneal (IP) injection of ⁴⁵Ca. An eighth group was fed a casein metal extrinsically labeled with ⁴⁵Ca. The absorption of calcium from legumes by rats averaged 47.1 ± 7.5% of IP dose. Average phytate content of the legumes was 1.7% and oxalate 0.37%. Raw legumes had an average of 15000 TIA units/g of whole bean, which were completely removed by cooking. Calcium absorption was unaffected by TIA or tannin content. Reduced availability of bean calcium was likely due to phytate and/or oxalate present in legumes.     

Hydrothermal Cooking Affects Protein Efficiency Ratio and Zinc Bioavailability of Soymilk-Based Diets in Rats

Hydrothermally cooked (HTC) and conventionally processed soymilks were compared with respect to protein efficiency ratio (PER) and zinc bioavailability in Sprague-Dawley rats fed isocaloric, isonitrogenous diets. When dietary zinc was 50 mg/kg, PER (mean ± SD, n = 12) was greater for HTC (processed 20 sec) (2.69 ± 0.34) than for conventional soymilk (2.39 ± 0.17). When dietary zinc was 20 mg/kg, PER (n = 10) was less for HTC processed 40 sec (1.86 ± 0.17) than for conventional soymilk (2.08 ± 0.19). Processing (HTC vs conventional) did not affect zinc bioavailability by the slope ratio bioassay procedure. PER of HTC processed 20 sec was higher than that of reference casein and conventional soymilk when dietary zinc was near recommended levels; pancreatic hypertrophy was not observed.     

Incorporation of Soymilk Lipid into Soy Protein Coagulum by the Addition of Calcium Chloride

ABSTRACT: The effect of protein composition on the lipid incorporation into protein coagulum (tofu curd) was investigated using soymilk prepared from mixtures of glycinin-rich and β-conglycinin-rich soybeans. The lipid incorporation takes place with the addition of CaCl₂ so that a particulate fraction of the protein is aggregated. The incorporation occurred by less addition of CaCl₂ with increasing glycinin in soymilk. The protein particle content and the glycinin content of the particles increased along with increasing glycinin. The lipid incorporation took place at lower CaCl₂ concentration when the particulate glycinin content was high. The mechanism of the lipid incorporation into soybean curd is discussed from these results.