固体枣粉饮料抗结块问题的解决

在超微粉碎时加入0．3％的抗结剂SiO2，将内包装充气量调整为内包装总容量的30％，在外包装中充填PE塑料衬托，可以彻底解决固体枣粉饮料保存期内结块问题。     

鸡粉调味料工业化生产抗结块试验研究

采用静止角度测试法,在工业化条件下进行鸡粉调味料抗结块性能试验.考察了干燥温度、产品粒度、抗结剂添加量及蔗糖粉末添加量对鸡粉调味料抗结块性能的影响,并在单因素试验的基础上进行抗结块正交试验.结果表明,影响产品抗结块性能的因素从大到小依此为:蔗糖粉末添加量＞产品粒度＞干燥温度＞抗结剂添加量;最佳条件为:蔗糖粉末添加量4%(W:W),干燥温度90℃,产品粒度50目,抗结剂添加量0.50%(W:W).     

调味盐的抗吸湿结块性能评价

研究通过检测结块率、结块强度、水分含量、吸湿率,对调味盐和未添加抗结剂食盐的抗结块性能进行对比分析,从而评价调味盐的抗吸湿结块性能。结果表明,未添加抗结剂食盐结块率、水分含量都随着加速时间的增加逐渐上升,而调味盐的结块率、水分含量都随着加速时间的增加几乎不变;调味盐和未添加抗结剂食盐在湿度小于75%时,都有很好的抗吸湿性能,在湿度大于75%时,随着时间的增加,调味盐的吸湿率比未添加抗结剂食盐增加得更慢。调味盐比未添加抗结剂食盐具有更好的抗吸湿结块性能。     

沙棘果渣对沙棘果粉的抗结块性能分析

沙棘果渣是由沙棘果汁生产加工过程中产生的副产品,具有较高的营养及利用价值。为了提高沙棘加工副产物的利用率,用沙棘榨汁后剩余的去籽果渣为原料,与纯沙棘果粉进行比较,研究沙棘果渣、抗结剂、果渣-抗结剂混合对沙棘果粉抗结的影响,以沙棘果粉结块率和流动性为指标,通过双指标加权法对沙棘果粉抗结条件进行综合评分。结果表明,沙棘果渣-抗结剂混合的抗结效果好,由单因素的试验结果,采用响应面软件分析,其最优条件以果渣粒度100目、果渣用量为14.50%、二氧化硅添加量为1.30%时,在此条件下沙棘果粉的休止角为47.55°、结块率为25.80%,其综合评分值为69.92分。说明,沙棘果渣-抗结剂混合能够较好的抑制沙棘果粉结块现象。本研究为进一步解决沙棘果粉结块的问题提供了思路。     

谷朊粉对冻干枣粉抑制吸湿作用研究

目的 研究谷朊粉对冻干枣粉吸湿特性的影响。方法 将谷朊粉与枣浆按不同比例均匀混合,真空冷冻干燥后粉粹,过60目筛制备不同配比的冻干枣粉。结果 谷朊粉显著降低了冻干枣粉的平衡含水率(equilibrium moisture content,EMC)。吸湿等温结果表明,红枣与谷朊粉质量比10:0、7:3、1:1、3:7样品的吸湿等温类型属“J”型增长,而0:10样品的属“S”型增长,表明谷朊粉的添加并未改变冻干枣粉吸湿等温类型;接触角随着谷朊粉的添加量的增大而增大,其值从31.22°增大到76.7°,说明谷朊粉可以减弱冻干枣粉的表面润湿性。从宏观和扫描电镜图中可知,冻干枣粉结块现象随着谷朊粉的添加量的增大而逐渐减轻。低场核磁结果显示,谷朊粉降低自由水的含量,减少水分向高自由度方向的迁移程度。结论 一定量的谷朊粉能够有效抑制冻干枣粉的吸湿,从而缓解结块的发生,保持流动性和分散性,进而提高冻干枣粉的品质。     

食用盐结块原理及不同材质外包装抗结块能力差异性分析

外包装一定程度上会影响食用盐的抗结块能力。文章对食用盐的基本结块原理进行分析,认为吸湿、放湿等是造成食用盐结块的最根本原理,对影响食用盐结块的因素包括粒度、对己量、杂质成分等因素进行总结,分析了在不添加抗结剂时,氧化膜、镀铝膜、铝箔膜等不同食用盐外包装抗结块能力的差异性,旨在为抗结块食用盐外包装开发提供借鉴。     

超微果皮粉的盐用抗结块性能研究

文章研究了3种天然绿色、可食用的防盐结块剂:超微苹果皮粉、超微香蕉皮粉、超微橘子皮粉。采用自主开发的结块测试方法对3种果皮粉及常用抗结剂的防结块性能进行比较,通过扫描电子显微镜(SEM)和电子能谱仪(EDS)分析手段探索这3种果皮粉的抗结机理。结果表明:判断超微果皮粉的抗结原理是物理隔离,为解决盐结块问题提供了新选择。     

响应面法优化枸杞粉抗结块工艺

利用响应面法分析吸湿时间、干燥剂添加量和抗结剂添加量对枸杞粉的抗结块效果,并探讨了包装方式及材料对枸杞粉结块度的影响。结果表明,在单因素实验中干燥剂与抗结剂对减缓枸杞粉结块的效果明显,根据单因素试验结果,进行响应曲面分析,以结块度为指标对枸杞粉抗结块的条件进行优化,通过多元回归拟合得到影响结块度因素依次为:Si O_2添加量吸湿时间 CaCl_2添加量。枸杞粉吸湿结块过程中抗结块的最优条件为:添加CaCl_2质量分数为0. 06%、添加Si O_2质量分数为1. 00%、吸湿时间为12 d,在此条件下实际测得结块度为48. 73%。在最佳抗结块条件下,真空包装抗结块效果优于非真空包装,在同一真空度下,不同包装材料对枸杞粉抗结块的效果依次为聚乙烯透明塑料包装(PE)牛皮凝膜纸包装(牛皮纸/PE)铝箔复合膜包装(铝箔/PE)。     

牛磺酸防结块研究

针对牛磺酸在贮存、运输、食用、加工过程中结块问题,采用磷酸三钙、超细二氧化硅、辛烯基琥珀酸铝淀粉三种抗结剂分别与牛磺酸均匀混合,在快速结块装置中密封加压一段时间后,通过测量其拉裂力,对不同抗结剂的防结块性能进行研究。结果表明,总体上,抗结剂加入量越大,抗结块的效果越好。磷酸三钙是三者中最理想的抗结剂。     

魔芋超强吸水剂在奶茶粉中的抗结性能研究

测试了魔芋超强吸水剂(KSAP)和二氧化硅的吸湿和保水性能,并比较了二者在奶茶粉中不同剂量的抗结性能.结果表明:在RH=90%±3%、T=25±1℃的高湿环境中放置3个月,奶茶粉添加2.5‰的KSAP抗结性能优于添加2.5‰的二氧化硅,其流动性指数为62.5,水分活度为O.385;在奶茶粉中,KSAP比二氧化硅更具有竞争吸湿抗结的优势.     

益生菌配方奶粉中水分活度的控制

为控制益生菌配方奶粉的水分活度,降低益生菌在配方奶粉中的衰减率,采用了干燥粉末法测定不同生产工艺配方奶粉的临界相对湿度。在临界相对湿度条件下,考察配方奶粉水分质量分数和水分活度的关系。结果表明:在25℃条件下,湿法奶粉的临界相对湿度为50%,干法奶粉为40%。在临界相对湿度下,益生菌配方奶粉的水分质量分数和水分活度呈正相关性,当湿法奶粉水分质量分数在2.4%以下,干法奶粉在1.9%以下时,能满足益生菌奶粉的水分活度在0.2以下的要求。     

冬枣粉吸湿的色泽、热力学特性及糖物质基础分析

为充分了解枣粉吸湿过程中的水分吸附特性,本研究采用静态称量法,分别测量枣粉在温度20、30、40 ℃,水分活度0.112～0.946下的吸湿情况,探究超微粉碎前后枣粉吸湿色泽的变化、吸附等温线、热力学性质及糖物质基础。结果表明,枣粉吸湿后褐变现象严重,其吸附等温线是III型,Peleg模型最适合描述枣粉的吸附等温线（平均相对预测误差E＜5%）。净等量吸附热和微分熵随着枣粉平衡水分含量（干基,下同）的增加呈指数降低,且超微粉低于普通粉。普通粉和超微粉的绝对安全水分含量分别为0.237 5、0.223 5 g/g。普通粉和超微粉的水分吸附过程均满足熵-焓补偿理论,其吉布斯自由能分别是1 152.80、1 184.22 J/mol,该过程是一个焓驱动的非自发反应。单糖吸湿对照实验结果表明枣粉中吸湿的主要糖种类为果糖。本研究旨在为枣粉的加工工艺优化及贮藏条件的选择提供理论依据。     

红枣粉喷雾干燥加工工艺优化

本研究通过向枣浆中加入大豆蛋白和果胶酶来优化红枣粉的喷雾干燥加工工艺,在单因素实验的基础上,利用响应面分析法优化料液浓度、进风温度、雾化器转速,以红枣粉集粉率和水分含量为响应值,最终得出喷雾干燥红枣粉的最优工艺参数:进料浓度18%,雾化器转速440 r/s,进风温度170 ℃,在此条件下经验证实验所得红枣粉出粉率为57.81%±0.75%,含水量4.76%±0.08%。此方法提高了红枣粉集粉率,改善了红枣粉的品质,为红枣制粉深入研究提供参考。     

ACCELERATED STORAGE, SHELF LIFE AND COLOR OF MANGO POWDER

Vacuum‐dried mango powder was produced from mango pulp through the addition of glycerol monostearate and tricalcium phosphate at 0.015 kg each per kg mango solids and maltodextrin at 0.62 kg per kg dry mango solids. The mango powder was packed in aluminum foil‐laminated pouches and stored in an accelerated storage environment maintained at 90% relative humidity (RH) and 38 ± 2C. The sticky‐point moisture content at 38 ± 2C was considered as the maximum moisture content to which the mango powder would remain stable. The shelf life of the powder predicted from this consideration and the Guggenheim‐Anderson‐de Boer (GAB) model for the water activity moisture content relationship was 114.68 days, whereas the actual shelf life was 105 days. The color change of the powder during storage followed first‐order reaction kinetics with a rate constant of 0.038 per day.     

Multi-objective Optimization of Spray Drying of Jujube (Zizyphus jujuba Miller) Powder Using Response Surface Methodology

Optimum technology of spray-dried jujube powder was studied using a Box-Benhnken design. Effects of weight ratio of maltodextrin and the dry matter weight of jujube pulp (WR, 3–5), inlet air temperature (T, 140–160 °C), and shift of feed flow rate (FFR, 3–5) on the quality attributes (moisture content, lightness, the total color difference, vitamin C (VC) content and hygroscopicity) of jujube powder were systematically studied by response surface methodology and perturbation plot. Analysis of variance showed that a second-order polynomial equation could predict the experimental data well (R ²?>?0.92). Moisture content and the total color difference (?E) were significantly affected by WR, T, and FFR. The higher WR and lower FFR resulted in a decrease in moisture content and ?E. WR and FFR had extremely significant effects on VC content and hygroscopicity (P?<?0.01); with lower WR and FFR, higher values of VC content and hygroscopicity would be received. The effect of WR was the most significant variable among others. The optimum conditions that maximizing VC content and minimizing contents of moisture, ?E, and hygroscopicity of jujube powder were found as WR of 3, inlet air temperature of 140 °C, and FFR of 3 ( i.e., 11 ml/min). Under these conditions, the response values were moisture content of 3.36 %, lightness of 83.32, ?E of 9.92, VC content of 205.10 mg/100 g, and hygroscopicity of 18.59 %, respectively.     

Untersuchungen zu Diffusionsvorgängen in mehrschichtigen Massivholzplatten

Multilayer solid wood spruce panels with different glueing and structure type were tested for water vapor diffusion for a wet climate (relative humidity ranging from 100% to 65% at 20°C) and for a dry climate (relative humidity ranging from 0% and 65% at 20°C). Results showed that the water vapor diffusion resistance for the dry climate is distinctly higher in comparison to the wet climate. The water vapor diffusion resistance is stronger related to the number of glue layers per panel thickness than to the type of adhesive. The average moisture content of the panels in a wet climate was 20%. If one considers a water saturation point of 28% (spruce wood) on the wet side, and 12% moisture content on the dry side (normal climate) of the panel a linear moisture gradient can be expected. Since the average moisture content of the solid wood panels was about 11.3% in a dry climate, and thus corresponding approximately to the equilibrium moisture content of spruce wood exposed to normal climate, the partial pressure gradient on equilibrium caused water uptake corresponding to the normal moisture content for spruce wood.     

Optimization of Short- and Medium-Wave Infrared Drying and Quality Evaluation of Jujube Powder

In this study, response surface methodology was used to optimize parameters of short- and medium-wave infrared drying processing for producing jujube powder. Optimization factors were power input (675–1,575 W), drying temperature (70–90 °C) and drying time (2.5–3.5 h), and responses were moisture content, L value, b value and vitamin C content of the jujube powder. Box–Benhnken center design was applied to the optimized the processing conditions. The optimal conditions for the production of jujube powder by the short- and medium-wave infrared drying method were power input of 1,125 W, drying temperature at 85.4 °C and drying time for 3.5 h. Under the optimal conditions, the values of moisture content, L, b and vitamin C content of jujube powder were 4.59 %, 64.46, 19.87 and 441.56 mg/100 g, respectively. Quality evaluation of the jujube powder was also investigated. The results were: hygroscopicity of 28.83 %, rehydration of 236.44 %, solubility of 53.59 %, bulk density of 0.70 g/ml, particle size of 154.2 μm, soluble solids content of 82.29 %, total sugar content of 46.87 %, reducing sugar content of 32.09 %, total acid content of 2.03 %, total flavonoids content of 1.45 % and cyclic adenosine monophosphate content of 75.32 mg/kg. The microstructure of jujube powder was irregular and 38 kinds of aroma components were generated.     

杏果粉片主成分吸湿性研究

针对杏果粉片加工、贮藏过程中吸湿性强而影响品质的问题,对杏果粉片配料的主要成分进行了吸湿特性研究,为杏粉片生产、贮藏环境的选择提供理论依据。采用25℃、相对湿度75%条件下测定各组分的吸湿速率和吸湿质量分数,确定吸湿平衡时间,在22.51%、32.78%、43.16%、52.89%、75.29%、84.34%、93.58%和100.00%的湿度条件下测定平衡后的吸湿质量分数,并根据25℃不同湿度条件下的吸湿平衡曲线测定其临界相对湿度。结果表明,杏粉、麦芽糊精、蔗糖、低聚麦芽糖的临界相对湿度分别为66%、74%、83%、77%,混合物颗粒的CRH为68%,因此在杏果粉片生产、贮藏过程中,常温条件下环境湿度应小于66%,以保证品质。     

非空调环境下制丝车间微雾加湿控制系统的设计

为解决干燥季节非空调环境下制丝车间相对湿度低而造成烟丝含水率波动大等问题,设计了一种微雾加湿控制系统.基于车间原有送新风系统,在新风入口处配置微雾加湿控制系统,通过生产区域的湿度传感器对加湿量进行控制,减小环境湿度波动,提高烟丝含水率稳定性.以龙岩烟草工业有限责任公司生产的"七匹狼"牌卷烟为对象进行测试,结果表明:应用...     

Glass Transition and State Diagram for Jujube Powders With and Without Maltodextrin Addition

Both water activity and glass transition concepts were used for stability evaluation of jujube powder in this study. The water sorption behaviour at 25, 35 and 45 °C and the relationship between water content (X _w), glass transition temperature (T _g) and water activity (a _w) were investigated for jujube powder with and without the maltodextrin addition. Moisture sorption isotherms of different jujube powders were of type III and BET model was the best for fitting the experimental data. The equilibrium moisture content of jujube powder containing 20% maltodextrin at a given a _w was lower than that of pure jujube powder. However, temperature had no significant effect on the moisture sorption of jujube powders. Values of T _g of different jujube powders were obtained using differential scanning calorimetry and the glass transition line was fitted to the Gordon-Taylor model. A depression in T _g with increasing water content was observed. State diagrams of different jujube powders were established based on the moisture sorption isotherm and the glass transition curve. Results showed that jujube powders with and without maltodextrin addition were stable at 25 °C when the water content was lower than 0.0673 and 0.0566 g/g solid, respectively.