营养强化玉米馒头粉的研究

在玉米馒头粉中添加（强化）复合营养素：维生素B，3．5mg／kg，B2 3．5mg／kg，尼克酸35mg／kg，叶酸2．0mg／kg，钙1000mg／kg，铁20mg／kg，锌25mg／kg，赖氨酸复合盐1．8g／kg，与对照组比较．对其流变学特性、营养品质做了基础分析，并进行了馒头和面条制作试验。研究表明：强化复合营养素使玉米馒头粉面团的稳定时间有所降低，但对面团的拉伸特性有一定的改善作用；玉米馒头粉强化复合营养素对馒头和面条的感官品质及内部质构没有产生明显的不良影响；玉米馒头粉营养强化后，其维生素、矿物质和赖氨酸等营养素含量明显提高。     

浙江省炒制香榧中9种矿物元素含量的研究

采集浙江省41个品牌炒制香榧样品,测定钾、镁、钙、铁、锰、锌、铜、硒和钠9种矿物元素含量,分析矿质元素含量的分布频率及区域差异。结果表明,香榧中9种矿物元素分别为钾12 639 mg/kg、镁5 047 mg/kg、钠2 532 mg/kg、钙2 119 mg/kg、锌117 mg/kg、铜67.0 mg/kg、铁61.9 mg/kg、锰35.6 mg/kg、硒0.224 mg/kg。浙江省炒制香榧钾含量高于一般干果,宁波地区硒含量显著高于绍兴、金华地区,部分香榧达到富硒产品标准。浙江省香榧中锌含量变异系数为179%,达极显著变异水平,诸暨市和磐安县香榧中锌含量远高于其他县,绍兴地区香榧中钾、锌、钙、镁显著高于金华等地区。     

青螺肉营养成分分析

对青螺肉的营养成分进行了检测和分析。新鲜的青螺肉中含有55.1%的粗蛋白,80%的水分,2.42%的脂肪。青螺肉中矿物质元素钙和锌的含量较高:42.3mg/kg的钙、121mg/kg的锌。新鲜的青螺肉中游离氨基酸的含量较高。     

硒营养强化对香菇营养品质影响研究

摘 要: 目的 考察硒营养强化剂添加量与香菇营养品质之间的关系。方法 以‘向阳二号’和‘9608’品种香菇为研究对象, 向栽培基质添加不同浓度硒营养强化剂, 考查所得富硒香菇中总硒及铜、锌、铁、锰、钾、钠、钙、镁等元素含量和16种氨基酸、粗蛋白、粗多糖、粗脂肪、粗纤维、粗灰分等含量。结果 两个品种香菇总硒含量均随硒添加量的增加而增加; 硒营养强化对香菇营养品质的影响与香菇的品种也有着很大关联, 硒添加量在0~40 mg/kg范围内, ‘向阳二号’大多数指标均呈先升高后降低的趋势, 天冬氨酸、甘氨酸、酪氨酸等含量在硒添加量2 mg/kg时达到最大值, 蛋白质、粗多糖、苏氨酸、缬氨酸等大部分氨基酸含量在硒添加量6 mg/kg时达到最大值; ‘9608’的天冬氨酸、苏氨酸、缬氨酸、蛋白质等大部分指标均在硒添加量40 mg/kg时达到最大值, 但大多都与未添加硒时差异性不显著。结论 对于不同品种的香菇, ‘向阳二号’添加2或6 mg/kg, ‘9608’添加40 mg/kg的硒营养强化剂时, 不仅可以提高香菇的富硒功效性, 还能在一定程度上对香菇品质起到提升作用, 本研究为富硒香菇品种的选择提供参考。     

红枣微量元素含量测定分析

利用微波消解-原子吸收分光光度法,测定分析红枣中微量元素含量,发挥不同品种红枣的药用和食用价值。红枣中6种微量元素含量分别是:铁21.01mg/kg～31.09mg/kg,钙607.40mg/kg～787.80mg/kg,铜1.97mg/kg～3.58mg/kg,锌6.46 mg/kg～14.91mg/kg,锰2.64 mg/kg～3.67 mg/kg,镁358.60 mg/kg～431.40 mg/kg。结果表明:红枣中微量元素的含量丰富,尤其是钙、镁、铁的含量较高。     

挤压碎米制备富锌强化大米

以粳米加工副产品碎米为原料,使用乳酸锌作为锌强化剂,通过挤压法制备富锌强化大米。将碎米粉碎成100?目,乳酸锌添加量2.0%,采用响应面法考察含水量、螺杆转速及机筒温度对富锌强化大米质构特性的影响。优化条件为含水量20%、螺杆转速80?r/min、机筒温度100?℃,制得富锌强化大米硬度为1?339.05?g,黏着性为0.75?mJ,弹性为0.79?mm,咀嚼性为967.42?mJ,锌含量为450.0?mg/kg。经X-射线衍射分析表明强化米中淀粉颗粒的结晶度较粳米明显减少,通过扫描电镜表征发现强化米淀粉颗粒外表面呈现不规则类似鳞片形状,并产生聚集现象,淀粉糊化温度由77.9?℃降低到56.2?℃,酶解反应完成后还原糖增加23.0%以上,有利于强化米淀粉颗粒的酶解作用。将其按1∶10的比例添加到粳米中,米饭口感、外观良好,锌含量为48.0?mg/kg。     

应用电感耦合等离子体发射光谱法测定食品中的钙铁锌

探讨了利用电感耦合等离子体发射光谱法(ICP-AES)同时测定食品中钙铁锌含量的测定方法。应用ICP-AES对奶粉成分标准物质(GBW 10017)中的钙铁锌含量进行测定,结果表明:方法具有灵敏度高、检测限低、高效、稳定的优点,方法的检出限分别为钙0.1mg/kg,铁0.02mg/kg,锌0.01mg/kg,相对标准偏差低于6%。     

毕节地区初烤烟叶中微量元素含量分布特征研究

对贵州毕节地区各县(市)不同植烟区域275个初烤烟叶中、微量元素进行了分析。结果表明,毕节地区烟叶中、微量元素含量较为适宜,铜、锌、锰、铁、镁、钙的平均含量分别为7.89 mg/kg、40.51 mg/kg、225.96 mg/kg、444.72 mg/kg、0.46%、2.95%;铜、锌、钙含量处于适中水平,锰、铁含量处于较高或高水平,镁含量处于较低水平。锰含量高的烟样主要分布在毕节、大方、黔西、金沙和纳雍;钙含量高的烟样主要分布在金沙、黔西和织金;全区烟叶镁含量普遍偏低。中微量元素在烟叶的不同部位上分布较有规律,锰、铁、钙元素的含量随烟叶部位的上升而下降,而铜和锌的含量随烟叶部位的上升而上升。     

添加剂对石膏型卤水体系硫酸钙结晶动力学影响研究

水溶开采的硫酸钙型卤水中除主要含氯化钠外,还含有大量的钙和硫酸根离子,这不仅影响真空盐产品的纯度,同时在真空蒸发罐及卤水回用过程的管道输送过程中结垢严重,对生产过程影响较大.实验测定了硫酸钙型卤水中硫酸钙的溶解度曲线.采用十二烷基苯磺酸钠,重铬酸钾和聚乙二醇作为添加剂,研究了添加剂对硫酸钙型卤水体系中CaSO4·2H2O结晶动力学的影响.结果表明:重铬酸钾的加入量为150 mg/kg～250 mg/kg时,其促进CaSO4·2H2O晶体生长,当重铬酸钾的添加量为210 mg/kg时,其对CaSO4·2H2O晶体生长促进作用最明显,此时线生长速率为9.333×1010 m/s;聚乙二醇作为添加剂在较大范围内都会对CaSO4·2H2O结晶过程起较为明显的促进作用,开始随着添加量的增加,得到的CaSO4·2H2O晶体产品的粒径将随之增大.当添加量为400 mg/kg时线生长速率达到最大值,为2.057×10-9 m/s;十二烷基苯磺酸钠的添加浓度小于300 mg/kg时,其促进石膏型卤水体系CaSO4·2H2O晶体的生长.当添加量为30 mg/kg时,CaSO4·2H2O晶体的粒径达到最大值,此时的线生长速率为1.290×10-9 m/s.     

半胱胺对肉仔鸡部分生理生化指标的影响

试验选择144只1日龄的AA肉仔鸡随机分为4个组(Ⅰ、Ⅱ、Ⅲ、Ⅳ组);预饲1周后分别在基础日粮中添加0、50、100、150 mg/kg的半胱胺,于添加半胱胺后第2、4和6周龄时颈静脉采血,测定血液中红细胞数、白细胞数、血红蛋白含量,血清中葡萄糖、钙、磷、钾、镁、铜浓度以及血清中碱性磷酸酶(ALP)、丙氨酸氨基转移酶(ALT)和门冬氨酸氨基转移酶(AST)活性,研究半胱胺对肉仔鸡部分生理生化指标的影响。结果表明:饲料中添加适量的半胱胺(50~100 mg/kg)能提高血液中红细胞数、白细胞数、血红蛋白含量和血清中钾、钙浓度,降低血清中镁、铜浓度,对肉仔鸡血清中磷、血糖浓度影响不明显。添加50~100 mg/kg的半胱胺对ALT、AST活性影响不明显;而ALP活性随着半胱胺添加量的增加而升高。说明肉仔鸡饲料中半胱胺的添加量以50~100 mg/kg为宜。     

奇亚籽皮多糖对冰淇淋乳化稳定性及品质的影响

考察不同质量浓度（0.5、1.0、1.5、2.0 mg/mL）的奇亚籽皮多糖作为乳化稳定剂在冰淇淋产品中的应用,通过对冰淇淋浆料稳定性和冰淇淋膨胀率、融化率、质构、气泡分布及结构特性等指标的测定,考察不同质量浓度奇亚籽皮多糖对冰淇淋品质的影响规律。结果表明：随着奇亚籽皮多糖质量浓度的增加,冰淇淋浆料的稳定性及冰淇淋的膨胀率、质构特性（弹性、黏附性、咀嚼性）提高,融化率和硬度降低,冰淇淋中气泡分布更加均匀,气泡直径均一,数量增多。添加奇亚籽皮多糖可提高冰淇淋浆料的表观黏度,冰淇淋浆料均表现出假塑性非牛顿流体。与空白冰淇淋样品对比,添加0.5 mg/mL质量浓度的奇亚籽皮多糖冰淇淋,其各性质测定结果略有改善,但质量浓度大于1.5 mg/mL时,可显著提高冰淇淋抗融性及稳定性,降低其硬度,改善其微观结构,气泡分布更均匀,使冰淇淋组织更加光滑。相较于空白冰淇淋样品,奇亚籽皮多糖的添加对冰淇淋的品质特性、结构特性及稳定性方面均有显著改善作用,为奇亚籽皮多糖应用于冰淇淋食品生产提供一定科学依据。     

Effect of calcium chloride addition on ice cream structure and quality

The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of κ-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added κ-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L⁻¹ = 40 mM of added Ca²⁺), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L⁻¹ added CaCl₂ and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of κ-carrageenan. These results can be explained by the interaction between Ca²⁺ ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum β-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization.     

The effect of inulin on the physicochemical properties and sensory attributes of low-fat ice cream

The aim of this study was to investigate the feasibility of replacing the ice cream fat with inulin to produce a low-fat ice cream with prebiotic properties. For this purpose, inulin (2, 3 and 4%, w/w) was added to the low-fat ice cream and the physicochemical and sensory properties of the resultant ice creams were compared with those of control ice cream (containing 10% fat) and the inulin-free low-fat ice cream. The composition, pH and acidity of the ice cream mixes were measured and the melting rate, colour and texture of the frozen ice cream samples were examined. The results indicated that the low-fat ice creams had a significantly lower melting rate in comparison with the control. Inulin addition caused the adhesiveness and hardness of the low-fat ice creams to decrease significantly compared with inulin-free low-fat ice cream.     

自由基氧化的乳清蛋白在冰淇淋中的应用

研究经羟基自由基产生体系氧化后的乳清蛋白在冰淇淋中的应用,测定蛋白氧化的主要指标羰基含量,并对影响冰淇淋品质的主要参数(包括膨胀率、抗融性、保形性)以及感官指标进行评定。结果表明：在冰淇淋中添加经H2O2体系氧化后的乳清蛋白,产品各项指标明显好于添加FeCl3体系的冰淇淋,且能够提高产品的性能,尤其是添加氧化1h的氧化蛋白其感官评分达到最大,但同对照比口感略有降低。这说明,适当的氧化可以改进产品的品质,提高产品的可接受性,但需改进口感。     

不同改性淀粉对冷冻酸乳冰淇淋品质的影响

通过添加不同改性淀粉制备冷冻酸乳冰淇淋,分别研究不同改性淀粉及添加量在冷冻处理前对酸乳样品的硬度和黏度的影响,以及在冷冻处理后对冷冻酸乳冰淇淋样品冻融稳定性和感官品质的影响。结果显示,随着改性淀粉添加量在0～1.2 g/100 g范围增加,酸乳样品的硬度和黏度均呈现不同程度的增加,并且全部冷冻酸乳冰淇淋样品的乳析指数均呈现不同程度的下降,其中添加辛烯基琥珀酸酐（OSA）酯化淀粉微粒的样品,其硬度和黏度的增幅最大,分别为67.64%和93.43%,并且表现出最佳的冻融稳定性,其乳析指数下降幅度最大,为52.28%。当OSA酯化淀粉微粒添加量为0.8 g/100 g时,其感官品评综合得分最高,为90.54分,表明此种改性淀粉在提高冷冻酸乳冰淇淋品质上具有良好的应用效果。     

Effect of the fat globule sizes on the meltdown of ice cream

The meltdown of ice cream is influenced by its composition and additives and by fat globule size. The objective of this study was to examine the effect of fat globule size and fat agglomerate size on the meltdown stability of ice cream. Therefore, an ice cream mix (10% milk fat) was homogenized at pressures ranging from 0 to 30 MPa in single-stage, double-stage, and selective homogenization processes. The ice cream, produced on a continuous ice cream freezer, was characterized by an optimized meltdown test while, in addition, the fat globule sizes and the free fat content were determined in the mix and the molten ice cream. The meltdown was dependent on the fat agglomerate sizes in the unfrozen serum phase. Agglomerates smaller than a critical diameter led to significantly higher meltdown rates. Homogenization pressures of at least 10 MPa were sufficient to produce a stable ice cream. Furthermore, proof was provided that double-stage homogenization is not necessary for fat contents up to 10% and that selective homogenization is possible to produce stable ice creams. Based on these results a model was deduced describing the stabilizing mechanisms during the meltdown process.     

Physicochemical properties and organoleptic aspects of ice cream enriched with microencapsulated pistachio peel extract

The purpose of this study was to produce a functional ice cream by the addition of microcapsules of pistachio peel extract (MPPE). Various properties of the resulting ice cream were investigated. By increasing the amount of MPPE the total phenolic content and antioxidant activity increased about 2.0‐ and 3.7‐fold, respectively, compared with the control sample. The rheological properties of the mixes were fitted by the Power Law model. All mixes showed non‐Newtonian pseudoplastic behaviour. By increasing the concentration of MPPE, the consistency coefficient (m), viscosity, and shear sensitivity were increased, but the flow behaviour index (n) decreased. The addition of MPPE to ice cream mixes improved the melting resistance, first dripping times and functional properties of ice cream such as antioxidant activity and total phenolic content. The results of the sensory analysis showed that the addition of MPPE had no significant effect on the overall acceptability of the product. Based on our findings, MPPE has the potential to be used as an added‐value ingredient in the ice cream industry to enhance the functional properties of their products.     

稳定性二氧化氯消毒剂及在冰淇淋生产中的消毒试验

介绍稳定性二氧化氯的优良特性和杀菌机理,并在冷饮生产中进行消毒实验。结果表明:100mg/kg ClO_2浸泡管道30min对冰淇淋生产卫生是合理可行的。     

Influence of Cape gooseberry (Physalis peruviana L.) addition on the chemical and sensory characteristics and mineral concentrations of ice cream

In this research, the influence of Cape gooseberry (CG) addition at different concentrations (5, 10 and 15%) on the physical, chemical and sensory properties and mineral contents of ice cream was investigated. The increment of CG concentration caused the decrease of fat, protein, pH and overrun values in ice cream, on the contrary it increased the total solid, ash, titratable acidity, viscosity values and first dripping and complete melting times. S contents of ice creams significantly increased with the CG addition. Moreover, CG increased K, and Na concentrations of ice cream, while lowered Ca and P contents. Mg contents of ice creams didn't change with CG addition (P > 0.05). Fe, Zn, Mn and Ni were determined as minor elements in ice cream samples and a significant increase was observed in Fe, Zn and Mn values (P < 0.05). The addition of CG did not affect Ni content of ice creams. The sensory results indicated that the ice cream containing 15% CG was the highest-scored by the panelists.