腌制剂对蒸煮火腿中亚硝酸钠残留量和亚硝胺形成影响的研究

为探讨低温蒸煮火腿生产过程中腌制剂对亚硝酸钠(NaNO2)残留量和二乙基亚硝胺(NDEA)形成的影响,在腌制过程中分别添加了抗坏血酸钠和三聚磷酸钠(STPP),研究了蒸煮火腿中NDEA及NaNO2含量的变化。结果表明,抗坏血酸钠能够显著降低(p<0.05)NDEA的形成量,随抗坏血酸钠添加量的增加,NDEA下降速度增大;同时能明显降低蒸煮火腿中NaNO2的残留量。添加STPP的处理组NaNO2残留量有所增加,随加入量的增加,NaNO2残留量上升趋势减缓;一定程度上提高蒸煮火腿中NDEA的形成量。     

芭蕉芋淀粉的催化氧化

本文探讨了催化剂的种类、次氯酸钠的用量和反应时间对芭蕉芋淀粉氧化反应的影响.结果表明:氧化淀粉中的羧基随次氯酸钠的用量和反应时间的增加而增加,但粘度不断下降.有效氯为2%时,淀粉中羰基含量最高.使用催化剂A可制备羧基和羰基含量都较大的氧化淀粉,使用KI则可制备羧基少而羰基含量高的氧化淀粉.     

Effect of Processing on Anti-nutritional Factors of Red Kidney Bean (Phaseolus vulgaris) Grains

The effect of different processing methods (soaking in water or solutions of sodium bicarbonate, citric acid, soaking plus cooking, and germination) on anti-nutritional factors (phytic acid, total polyphenols, tannins, and hydrocyanic acid) of red kidney bean was studied. The anti-nutritional factors were reduced significantly (P < 0.001) with processing techniques. Cyanide contents were most effectively (25%) reduced by cooking after soaking in sodium bicarbonate solution, followed by germination. The most drastic effect was noted on tannin contents. Cooking after soaking in either citric acid or sodium bicarbonate solutions almost eliminated it. However, simple soaking in water did not result in any reduction in tannin contents. Reduction in total polyphenols was 78.7% with cooking after soaking in sodium bicarbonate solution. Phytic acid contents were reduced only with germination treatment (42.6%), while the other treatments did not bring about any large reduction.     

The effect of selected functional additives and heat treatment on nitrosamine content in pasteurized pork ham

The influence of pasteurization and sodium chloride, sodium ascorbate, polyphosphates and sodium nitrite coupled with pasteurization on nitrosamine contents in pork was studied. Nitrosamines: dimethylonitrosamine (DMNA) and diethylonitrosamine (DENA) were extracted from raw material, distilled, condensed in an evaporator under lowered pressure and analyzed chromatographically. An inhibitory effect of NaCl and sodium ascorbate on volatile nitrosamines (DMNA and DENA) was seen. Adding solutions of polyphosphates to the meat caused a slight increase in nitrosamine contents, higher than noted with sodium chloride. The effect of these compounds on nitrosamine formation depended on the presence of polyphosphates and sodium nitrite in the brine. If the brine contained nitrites, the adverse effect of sodium ascorbate and NaCl on nitrosamine formation was weaker. Moreover, a strong inhibitory effect of pasteurization on DMNA and DENA formation was observed.     

干装苹果罐头减压预抽辅助碱性钙处理工艺优化

为控制干装苹果罐头果肉组织软化,以秦冠苹果为原料,通过单因素试验考察Ca2＋质量浓度、预抽真空度和预抽液pH值对不同钙形态（水溶性钙、氯化钠溶性钙、醋酸溶性钙、盐酸溶性钙）含量、细胞壁组分（水溶性果胶、螯合剂溶性果胶、碳酸钠溶性果胶、半纤维素）含量的影响。在此基础上,采用Box-Behnken试验设计方法和Design-Expert 8.0数据分析软件,以氯化钠溶性钙含量和螯合剂溶性果胶含量为响应值优化干装苹果罐头减压预抽辅助碱性钙处理工艺。结果表明,氯化钠溶性钙含量和螯合剂溶性果胶含量在干装苹果罐头果肉组织中的含量最高,且各因素对二者的影响显著;当Ca2＋质量浓度2.0 g/L、预抽真空度0.08 MPa、预抽液pH 2.8时,干装苹果罐头氯化钠溶性钙含量为55.26 mg/kg,螯合剂溶性果胶含量为17.45 mg/g,与预测值的相对误差较小。该研究为调控干装苹果罐头果肉组织软化和指导生产实践提供部分理论依据。     

Effect of sodium chloride and moisture content on ammonification and nitrification in incubated soil

A study was made of the effect of different soil moisture contents (from near the wilting point to water-logging) combined with various levels of added sodium chloride (0.5-2.0%) on the accumulation of mineral nitrogen (ammonia plus nitrate) during incubation (30°) of a neutral clay loam for 3 and 6 weeks. The optimum moisture content (50% m.w.h.c.

1 m.w.h.c.=maximum water-holding acapacity

) for mineralisation and nitrification was not affected by addition of sodium chloride. The most pronounced effect of sodium chloride in reducing mineralisation and nitritification occurred at the lowest moisture content and was very marked even at the lowest level (0.5%) of sodium chloride. Nitrification was completely suppressed by 1-2% sodium chloride at all moisture contents but ammonification continued even with 2% sodium chloride. The presence of 1-2% sodium chloride resulted in loss of nitrate at both low and high moisture contents, whilst 0.5% sodium chloride caused loss of nitrate only at 25% m.w.h.c.     

四棱豆硒蛋白与其它硒源的生物利用研究

以雌性SD大鼠为研究对象建立低硒的动物模型,通过灌胃的形式给大鼠分别补充不同剂量的亚硒酸钠、富硒酵母和四棱豆硒蛋白。检测大鼠血清和肝肾中的硒含量、谷胱甘肽过氧化氢酶(GSH-px)、超氧化物歧化酶(SOD)、硫氧还蛋白还原酶(TrxR)的活性和丙二醛(MDA)的含量来比较其生物利用的效果。结果表明:与低硒对照组相比,所有加硒处理组的大鼠血、肝、肾中的硒含量以及所含的硒酶活性均明显提高(P<0.05),在同一补硒水平上,亚硒酸钠组的肝肾硒含量低于富硒酵母组和四棱豆硒蛋白组(P<0.05);亚硒酸钠组的血清和肝肾的谷胱甘肽过氧化氢酶(GSH-px)、超氧化物歧化酶(SOD)、硫氧还蛋白还原酶(TrxR)的活性和丙二醛(MDA)的含量都低于富硒酵母组和四棱豆硒蛋白组(P<0.05)。结论:四棱豆硒蛋白和富硒酵母增加大鼠的硒含量高于亚硒酸钠组(P<0.05),其它硒酶的影响是四棱豆硒蛋白最优,硒蛋白能更好地被低硒大鼠吸收利用。     

果胶、黄原胶、海藻酸钠、耐酸性CMC对丝素酸奶乳酸菌数的影响

采用两因素三水平析因试验设计,考察了4种常用的酸奶稳定剂(果胶、黄原胶、海藻酸钠、耐酸性CMC)对搅拌型丝素酸奶乳酸菌数的影响。结果显示:果胶、黄原胶、海藻酸钠、耐酸性CMC对丝素酸奶的乳酸菌数均有极显著的影响(P<0.01),其中黄原胶、海藻酸钠和丝素对乳酸菌数有极显著的交互作用(P<0.01),果胶和丝素对乳酸菌含量有显著的交互作用(P<0.05),耐酸性CMC和丝素对酸奶的乳酸菌数无显著的交互作用(P>0.05)。4种稳定剂中,黄原胶和海藻酸钠可提高搅拌型丝素酸奶的乳酸菌数,其中添加1%丝素和0.03%海藻酸钠的酸奶的乳酸菌数最高,达到1.20×1011mL-1;其次为添加1%丝素和0.05%黄原胶的酸奶,乳酸菌数为1.07×1011mL-1。     

绿豆清爽饮料制备中护色剂选择及总黄酮含量测定

目的：在制备绿豆清爽饮料过程中,确定护色效果好且总黄酮提取率高的护色剂最佳配方。方法：对护色剂柠檬酸钠、异VC钠、三聚磷酸钠单独使用及其复合配方的护色效果和总黄酮含量进行单因素及正交试验研究,总黄酮含量采用分光光度法测定。结果：三种护色剂柠檬酸钠、异VC钠和三聚磷酸钠复合使用时均显著影响护色效果,对绿豆中总黄酮的提取率也有显著影响,各因素影响顺序为柠檬酸钠〉异VC钠〉三聚磷酸钠;得出最佳护色剂配比为：柠檬酸钠0.02%、异VC钠0.018%和三聚磷酸钠0.1%;通过重复试验制备的绿豆清爽饮料中的总黄酮含量为12.8±0.42mg/L。结论：柠檬酸钠的酸度调节作用、异VC钠的抗氧化作用和三聚磷酸钠的螯合作用,三者结合后方可显著提高绿豆色素的稳定性。     

Amino Acid Composition of Protein Fractions Extracted from Phaseolus Beans and the Field Bean (Vicia faba L.)

Protein fractions were extracted sequentially with 2% sodium chloride, 30% isopropyl alcohol, 4% lactic acid and 0.5% potassium hydroxide from three varieties of adzuki beans, kafae and red kafae bean, three varieties of lima beans and red lima bean, two varieties of kidney beans and field bean that were grown in the tropics and sub-tropics. The sodium chloride extract had the highest range of protein concentration (51.2 to 81.4%). The sodium chloride extract was separated into two fractions based on solubility in water. The amino acid compositions of the flour from the seed and of the two fractions from the sodium chloride extract were determined. High contents of lysine, aspartic acid, glutamic acid and leucine were obtained, whereas the sulphur-containing amino acids contents were low.     

灌肠制品中亚硝酸钠残留量及肉品发色率预测模型的建立

通过对亚硝酸钠添加量、异抗坏血酸钠添加量及原料肉中总色素含量与亚硝酸钠残留量及肉品发色率之间的关系的研究,对实验数据进行了统计分析,建立了本研究范围内的亚硝酸钠残留量及肉品发色率的预测模型:Y1=17.082+0.181X1-0.017X2-0.026X3和Y2=58.466+0.007X1+0.033X2+0.022X3,其中Y1、Y2、X1、X2、X3分别代表亚硝酸钠残留量(mg/kg)、肉品发色率(%)、亚硝酸钠添加量(mg/kg)、异抗坏血酸钠添加量(mg/kg)、原料肉中的总色素含量(mg/kg)。     

不同亚硫酸盐预处理对蔗渣化机浆白度的影响

蔗渣原料分别经中性亚铵法预处理和碱性亚钠法预处理，在得率及磨浆后打浆度均相近，漂白条件相同的情况下，未漂浆及漂后浆的白度存在明显的差别。对两种浆料有关化学组份的研究表明，造成两种浆料白度及可漂性差别的原因主要为：（１）浆料的木素含量不同，纤维各形态区域的脱木素率不同；（２）木素中共轭羰基等发色基团的含量有差别；（３）浆料中的苯醇抽出物含量及性质不同；（４）亚硫酸按预处理过程中蔗渣木素内可能增加了新的含氮基团，形成了某种发色结构。     

草珊瑚总黄酮稳定性研究

以草珊瑚总黄酮含量为指标考察其提取液的稳定性,研究结果表明:乙醇提取法草珊瑚总黄酮稳定性好、提取率高,其提取率是沸水提取法的3．25倍;在八种常用的附加稳定剂中以硫代硫酸钠,亚硫酸钠对总黄酮的稳定性影响较大,可使总黄酮含量降低21．98%～12．07%;草珊瑚提取液中总黄酮含量在存放三年中平均每年降低0．86%,在100℃加热30min后降低0．82%,变化甚微,是非常稳定的:强光直射30h可使提取液中总黄酮含量平均下降10．27%,对稳定性影响较大:提取液的pH值在4～6时总黄酮含量最稳定。     

红薯不同部位抑制亚硝化反应能力及总黄酮含量比较

测定了红薯不同部位提取物对N-亚硝胺(NDMA)合成阻断、对亚硝酸盐的清除能力及其黄酮类化合物的含量,并比较了它们之间的相关性。结果表明:在体外模拟人体胃液的条件下,红薯各部位提取物均有抑制亚硝化反应的作用,其中红薯叶对N-亚硝胺(NDMA)合成阻断及对亚硝酸盐的清除最佳,依次为红薯茎、红薯梗;其阻断和清除率随提取物浓度增加而增加;不同部位提取液对N-亚硝胺(NDMA)合成阻断作用、对亚硝酸盐的清除作用与总黄酮含量相关,相关系数分别为0.987 4、0.960 3。     

Contents of macro and microelements in fresh and frozen dill (Anethum graveolens L.)

The level of ash and its alkalinity and the contents of potassium, sodium, magnesium, iron, phosphorus, zinc, copper, cadmium, and lead, were determined in green dill (leaves and whole plants, about 20 cm in height, harvest time). The two usable parts were frozen using variable pretreatments (blanching or no blanching) and different storage temperatures (−20 and −30 °C). Analyses were conducted after 0, 3, 6, 9, and 12 months of refrigerated storage. Fresh leaves contained more ash, magnesium, iron, phosphorus, zinc, cadmium and lead but less sodium and copper than whole plants, while the contents of potassium and calcium were similar. Blanching significantly reduced the level of ash and its alkalinity and of potassium, calcium, magnesium, phosphorus, zinc, copper, cadmium, and lead, both in the usable parts of the plant, and of sodium in whole plants and of iron in leaves. During the storage period, changes in the contents of the analysed constituents did not depend on the usable part or storage temperature, being statistically significant only for the contents of iron and copper in the two usable parts of frozen non-blanched dill.     

植烟土壤适宜施硒量研究

采用大田试验方式,在硒含量较低的土壤上施用亚硒酸钠,分析其对烤后烟叶硒含量、品质及卷烟产品安全性的影响,确定了植烟土壤适宜施硒量。结果表明：（1）烤后烟叶硒含量随土壤施硒量增加呈现抛物线趋势,当土壤施用亚硒酸钠量为13.50 kg/hm²时,烟叶硒含量最高。（2）土壤施用亚硒酸钠为6.75~11.25 kg/hm²时,烟叶烟碱等化学成分含量较适宜、可用性较高,评吸质量较好。（3）富硒烟叶可降低卷烟产品细胞急性毒性、致突变能力以及诱导细胞活性氧产生的能力。通过综合分析土壤施硒量对以上各种指标的影响,确定植烟土壤施用亚硒酸钠的适宜量为6.75~11.25 kg/hm²。     

不同添加剂对速煮重组米品质的影响

以速煮重组米的感官品质、质构特性、糊化度、水溶性碳水化合物(WSC)及色差等为指标,研究了单甘脂、硬脂酰乳酸钙钠(csl-ssl)、蔗糖脂肪酸酯(SE-15)、软磷脂、复合磷酸盐、焦磷酸钠等6种添加剂对速煮重组米品质的影响,并确定最佳添加量。结果表明,单甘脂、硬脂酰乳酸钙钠、SE-15、软磷脂、复合磷酸盐、焦磷酸钠的添加量分别控制在0.1%、0.2%、0.3%、0.6%、0.15%、0.15%为宜。     

减盐火锅底料对牛肉食用品质及钠、钾含量的影响

以牛肉(牛里脊肉)为原料,在不同比例NaCl和KCl组成减盐配方的火锅底料中涮制不同时间,比较KCl替代比例及涮制时间对牛肉感官评价、剪切力、蒸煮损失率的影响,并探究牛肉在减盐火锅底料中涮制前后盐含量、钠含量与钾含量的变化规律.结果表明:牛肉在NaCl、KCl质量比7:3的减盐火锅底料中涮制各时间点感官评分均最高,在不...     

Bestimmung von natriumhaltigen Zusatzstoffen in Holzwerkstoffen

Methods for the determination of sodium or sodium-containing components in wood and wood-based products are described. Sodium contents are shown for wood, urea formaldehyde (UF) resins, resol-type phenol formaldehyde (PF) resins, and particleboards produced with these resins.     

Effects of Sodium Fertiliser on the Chemical Composition of Perennial Ryegrass and White Clover Leaves of Different Physiological Ages

A field experiment was conducted to examine the effects of applying sodium fertiliser on the chemical composition of perennial ryegrass and white clover leaves of different physiological ages. When no sodium fertiliser was applied the cation concentrations increased up to the point of senescence in grass leaves and then declined in the dead leaves. Sodium fertiliser increased the contents of sodium from 6 to 9 g kg^-1 DM and magnesium from 2·2 to 3·4 g^-1 kg DM in young grass leaves, but both declined to a low level in dead leaves. It decreased the content of potassium in young grass leaves and calcium in older leaves. Clover leaves were less responsive to sodium fertiliser than grass, but older clover leaves had an increased sodium content and reduced calcium content when sodium was applied. All clover leaves responded to sodium by increasing chloride and reducing magnesium contents. The nutritional value of grass, but not clover, was reduced by sodium fertiliser, with an increase in fibre content and a decrease in crude protein content and DM digestibility. This probably occurred because of the high content of sodium in the herbage without sodium fertiliser. It is concluded that young grass leaves tend to be more responsive to sodium fertiliser than old leaves, and that clover is less responsive than grass. © 1997 SCI.