苹果冷冻干燥工艺优化

对苹果进行冷冻干燥实验,确定了苹果片冻干工艺条件。计算了冻结时间,干燥时间,并与实验值进行了比较。探讨了冻结速率,物料温度,干燥室及捕水器温度、压强对冷冻干燥过程及制品质量的影响。苹果冷冻干燥优化工艺参数为:冻结时间1.0h,升华干燥、解吸干燥时干燥仓压强分别为70～90Pa、20～30Pa,解吸干燥时物料温度50～60℃,物料厚度10mm,干燥时间为10h。     

苹果泠冻干燥工艺优化

对苹果进行冷冻干燥实验，确定了苹果片冻干工艺条件。计算了冻结时间，干燥时间，并与实验值进行了比较。探讨了冻结速率，物料温度，干燥室及捕水器温度、压强对冷冻干燥过程及制品质量的影响。苹果冷冻干燥优化工艺参数为：冻结时间1．0h，升华干燥、解吸干燥时干燥仓压强分别为70-90Pa、20-30Pa，解吸干燥时物料温度50-60℃，物料厚度10mm，干燥时间为10h。     

牛肉泠冻干燥过程优化及最佳工艺条件的确立

对熟牛肉进行冷冻干燥实验，确定了熟牛肉片冻干工艺条件。计算了冻结终点温度、冻结时间，建立了熟牛肉片冻干的传热传质模型，由模型计算出理论干燥时间，并与实验值进行了比较。探讨了原料、预冻速率、干燥室压强、升华温度、捕水器温度、压强对制品品质及干燥时间的影响。熟牛肉的冻干工艺条件为：预冻时间3h，预冻终点温度-24℃，干燥室真空度60Pa，捕水器压强45Pa，温度-40～-50℃，干燥时间4h。     

菠萝蜜真空冷冻干燥机理及工艺研究

本文对菠萝蜜进行了真空冷冻干燥研究,通过DSC差示扫描热量法,测定共晶点和共融点分别为-20.33℃和-9.87℃。分析了升华干燥温度,升华干燥时间与解析干燥温度对菠萝蜜品质及营养成分的影响,通过正交实验,确定了菠萝蜜真空冷冻干燥的最佳工艺参数。结果表明:在菠萝蜜尺寸为30mm×15mm×3mm,升华干燥温度为-10℃,真空度为200Pa,升华干燥时间为8h,解析干燥为35℃,解析干燥时间为2h,真空压力为1000Pa时,冻干后维生素C保留含量达71.26%,感官品质最佳。     

固体蜂蜜饮料工艺技术研究

以槐花蜜为原料,添加麦芽糊精,用饮用水稀释后,采用真空冷冻干燥工艺进行干燥处理。对各物质添加量和冷冻干燥工艺进行优化。结果表明:当麦芽糊精添加量为30%(按蜂蜜质量的百分比),料液的可溶性固形物含量10%,在-18℃条件下冷冻5 h左右至料液完全冻结,然后在冷阱温度-51℃、干燥温度45℃,料液分装厚度5 mm,真空度小于10 Pa的条件下干燥15 h左右,制取的固体蜂蜜饮料色泽晶莹洁白,呈均匀的蜂窝组织结构,有浓郁的蜂蜜风味,速溶性良好,口感佳。     

真空冷冻干燥法制备高纯度低聚果糖工艺的初步研究

由于高纯度低聚果糖(P-FOS)有受热容易降解的特性,选择使用冷冻干燥法对高纯纯度低聚果糖进行干燥试验。试验测得P-FOS的共晶点-32℃,共融点-26℃,并通过单因素试验确定出适宜的干燥工艺条件为:冷阱温度-50℃,预冷冻速率为12℃/h,时间为5～6h,辐射加热温度为40～55℃,真空度为550～600Pa,干燥周期10～16h,得到片状的P-FOS,经加工得到P-FOS干粉产品。     

方便米饭的真空冷冻干燥工艺

采用真空冷冻干燥方法确定冻干米饭的最佳工艺参数,并分析比较快速冻结和慢速冻结两种方法对冻干米饭的影响。结果表明：在冻结温度－ 50℃、时间1.5h;一次干燥温度－ 20℃、时间8h,二次干燥温度50℃、时间5.5h;真空度维持在10Pa 左右的条件下工艺最佳,并绘制了冻干曲线。而且从综合品质和营养角度上分析,快速冻结的产品具有更高的品质,附加值高。     

银鱼冷冻干燥的工艺

研究并优化了银鱼冷冻干燥时的工艺条件，包括预冻方式、加热板程序对冷冻干燥过程的影响，得出银鱼冻干工艺条件为：采用中速冻结的方式将银鱼预冻，在10Pa左右的真空度、冷凝器温度为-45℃的条件下，采用的加热板加热程序分别为0℃保持3h，10℃保持0．5h，20℃保持0．5h，然后将温度升高至40℃,当物料温度接近于加热板温度的时候表示物料基本冻干。     

黃蚬真空冷冻干燥工艺及模型研究

研究了黄蚬真空冷冻干燥的干燥模型,并实验确定了黄蚬冻干的优化工艺条件:当预冻温度为-30℃,升华干燥阶段的真空室压力为35～40Pa,解析阶段板层温度设为30%时,整个冷冻干燥过程用时约16.5h,干品黄蚬水分含量为2.1%,复水率达93.56%.     

正交实验优化冻干香蕉苹果派的配方和工艺

采用正交实验方法对香蕉苹果派的配方和升华干燥技术进行研究。结果表明,按照冻干香蕉粉-冻干苹果粉-奶粉-果葡糖浆=1∶0.75∶0.5∶0.25重量比例;升华干燥参数为:冻结时间3小时,在60~80Pa、80℃5h后,干燥温度依次为70℃→60℃→50℃,至水分含量小于5%,即可获得外观完整,香蕉味、苹果味和奶粉味鲜浓,口感上佳、质松脆,口感独特的香蕉苹果派。     

冷冻面条制备工艺研究

制备工艺对冷冻面条品质至关重要。该研究对不同工艺所制备冷冻面条感官评分、质构测定参数及溶出率进行对比,发现冷冻面条最佳制备工艺为:将面片厚1.1 mm,面条宽3.4 mm生面条,置于蒸饭机中蒸25分钟后取出,沸水中煮4分钟至熟,冷却后在–40℃下速冻30分钟(面条中心温度达到–18℃),然在–18℃条件下冻藏。该工艺所制备冷冻面条具有最适宽度和厚度,兼具蒸和煮优点,且改进各自缺点,感官评分优良,溶出率也在合适范围内。     

后发酵冷冻面团成品品质影响因素的研究

主要对后发酵冷冻面团的品质变化进行了研究,在醒发室温度和湿度恒定的条件下,研究发酵时间和添加剂对冷冻面团所得馒头的比容、色度等品质的影响。并通过正交实验确定最佳的后醒发时间为25min,添加剂组合为:单甘酯0.37%,Vc添加量0.08%,抗冻剂0.08%,     

Study on processing and quality improvement of frozen noodles

The processing method and quality improvement of frozen noodles were studied. To obtain the best mouthfeel and control the breakage during processing and cooking, noodles with a thickness of 1.1 mm and width of 3.4 mm were produced. The precooking method for raw noodles was steaming for 10 min and then boiling for 4 min before freezing to obtain the optimal characteristics for frozen noodles. Five frequently used food additives (guar gum, sodium stearyl lactate (SSL), cassava starch, glucose oxidase (GOD), and α-amylase) were used to improve the quality of frozen noodles. Cooking losses and sensory evaluation scores were adopted to optimize the formulation of frozen dough by a response surface methodology (RSM): guar gum 0.28%, SSL 0.44%, cassava starch 4.82%, GOD 0.003%, and α-amylase 0.04%. Frozen noodles had a more continuous microstructure and their storage quality was improved notably by this method.     

解冻和加工过程中冷冻猪肉保水性的研究

以冷冻猪4号肉为原料,研究解冻和加工过程中肉的来源、解冻方法、肉本身所含磷酸盐及加工过程中添加的磷酸盐对肉的保水性等指标的影响。结果表明:解冻过程中,解冻方法对猪肉的解冻汁液损失影响较大,肉流水解冻时汁液损失最小,保水性最好。当肉的来源不同时,汁液损失也不相同。肉本身所含磷酸盐对肉的解冻汁液损失影响较小。加工过程中添加不同浓度磷酸盐,对肉的保水性等指标影响显著(P<0.05)。当磷酸盐添加量≥0.4%时,肉的离心损失会显著下降(P<0.05)。在对肉保水性的影响方面,加工时添加的磷酸盐与解冻后肉本身所含磷酸盐及解冻方法之间存在交互作用。     

Effect of frozen storage on the structure and enzymatic activities of myofibrillar proteins of rabbit skeletal muscle

The effect of frozen storage on the biochemical properties of myofibrils, and of their major constituents, actin and myosin, was investigated. Extractability of myofibrillar proteins increased slightly for 3 weeks during frozen storage of muscle, decreasing thereafter. The change in myofibrillar ATPase activity during frozen storage was consistent with that of a reconstituted acto-heavy meromyosin (HMM) complex prepared from frozen stored muscle at the same weight ratio of actin to myosin as in situ. However, myosin ATPase activity showed a different pattern of change when compared with myofibrillar ATPase activity. The maximum velocity of acto-HMM ATPase activity and the apparent dissociation constant of the acto-HMM complex decreased for 1 week during frozen storage, increasing thereafter, indicating that the affinity of actin for myosin was greatest in muscle which had been frozen for 1 week.     

冷冻鱼糜及制品中磷酸盐测定的研究

研究冷冻鱼糜及制品中磷酸盐含量的测定方法.采用分光光度计,确定了测定体系的特征吸收波长和显色条件,并建立标准曲线与回归方程.磷酸盐测定体系的特征吸收波长为825 nm,吸光度与磷酸盐含量间的回归方程为y=0.006x-0.005,在0.8 μg～100μ.g范围内具有良好的线性关系(R2=0.999),对于不同的样品其...     

冷冻调理马铃薯饼加工技术的探讨

对马铃薯的预糊化实验结果揭示,在各种加热方法中,马铃薯经蒸煮25min后的糊化效果最好.正交试验结果表明,奶粉含量和黄油含量对冷冻调理马铃薯饼的感官指标有高度显著的影响.对冷冻调理马铃薯饼的油脂的测试结果显示,未经油炸的马铃薯饼的脂肪含量为4.24%,而经过油炸后的马铃薯饼的脂肪含量为11.18%.经过一个月的冻藏后,未经油炸的冷冻调理马铃薯饼的油脂的过氧化值为1.94%,而经过油炸的冷冻调理马铃薯饼的油脂的过氧化值为7.79%.     

和面及揉面方式对冷冻熟面品质的影响

为研究不同和面方式(真空、普通和手工)以及不同揉面方式(机器揉面、手工揉面和不揉面)对冷冻熟面蒸煮和质构特性的影响,采用低场核磁技术分析加工方法对面条中水分状态的影响,并通过高效液相色谱图分析面条内部蛋白质的变化。结果显示:采用真空和面的冷冻熟面质构性质和蒸煮特性最好,深层次结合水比例高,SDS(十二烷基硫酸钠)蛋白可提取率低,说明真空和面可以促进面筋蛋白的交联,使面筋形成更加充分均匀,与水分的结合更加紧密;揉面过程尤其是手工揉面可以使冷冻熟面的蒸煮特性和质构性质提高,使深层次结合水含量升高,SDS蛋白可提取率降低,说明揉面可以促进面筋蛋白与水的结合,使面筋蛋白形成更加充分。     

添加剂对冷冻面团馒头品质的影响

对冷冻面团制作馒头进行了尝试,研究了羧甲基纤维素钠、硬酯酰乳酸钙钠、谷朊粉、维生素C以及它们复合对冷冻面团馒头品质的影响,结果表明:冷冻面团技术也可用于生产馒头,冷冻面团馒头复合品质改良剂的最优配方为:谷朊粉4%,硬酯酰乳酸钙钠0.05%,维生素C0.006%,羧甲基纤维素钠0.6%,此时冷冻面团馒头的品质较好。     

The impact of home freezing on the sensory characteristics of ready-to-use leafy vegetables

BACKGROUND: Owing to the increasing trend of consumption of ready‐to‐use leafy vegetables, the necessity of determining the best conditions for their frozen storage and the considerable impact of freezing on their sensory attributes, research was carried out to determine the best freezing temperature and storage time for a mixture of Allium ampeloprasum, Lepidium sativum and Stureia hortensis. RESULTS: The results for freezing temperature at three different storage times showed that colour and overall acceptability at ? 18 °C were always ranked first (P < 0.05), while taste at ? 18 °C was ranked first on days 120 and 150. The results for frozen storage time at three different temperatures indicated that colour, taste and acceptability were not significantly different. CONCLUSION: Overall, the results of this research indicated that the sensory attributes of leafy vegetables during 180 days of frozen storage were affected mainly by freezing temperature rather than frozen storage time. Copyright © 2010 Society of Chemical Industry