干燥方式对不同接枝度的大豆分离蛋白-麦芽糊精聚合物性质影响

以大豆分离蛋白(SPI)和麦芽糊精(MD)为原料制备不同接枝度的SPI-MD聚合物,研究比较喷雾干燥和冷冻干燥两种处理方式对不同接枝度下的SPI-MD聚合物性质的影响,如溶解度、疏水性、持水性、乳化性、乳化稳定性及起泡性、泡沫稳定性等的影响。实验表明,喷雾干燥样品的溶解性,表面疏水性和乳化性高于冷冻干燥样品;冷冻干燥样品则具有较好的持水性。另外,两种干燥样品的乳化稳定性非常接近。不同接枝度的两种干燥样品起泡性差异较大,且泡沫稳定性都相对较差。     

不同干燥方法制备的星油藤分离蛋白功能性质的比较研究

以星油藤饼为原料,分别采用真空冷冻干燥和喷雾干燥的方法制备星油藤分离蛋白。研究了温度、p H、质量浓度对两种干燥方法制备的星油藤分离蛋白功能性质的影响并进行比较。结果表明:两种方法制备的星油藤分离蛋白的溶解度和吸油性在55℃时最大;持水性在p H 7时最大;黏度随温度的升高而降低;起泡性和乳化活性、乳化稳定性均随蛋白质质量浓度的升高而增大。真空冷冻干燥样品的吸油性、持水性、溶解性、起泡性大于喷雾干燥的样品;其乳化活性与乳化稳定性高于喷雾干燥的样品。     

大豆分离蛋白功能性质及其影响因素

作为一种食品添加剂,大豆分离蛋白广泛应用于各种各样的食品体系中。大豆分离蛋白的成功应用在于它具有多种多样的功能性质,功能性质是大豆分离蛋白最为重要的理化性质,如凝胶性、乳化性、起泡性、粘度等。本文主要综述大豆分离蛋白功能性质,并简要概述影响大豆分离蛋白功能性质的主要因素。     

两种干燥方式对亚麻籽分离蛋白功能性质的影响研究

以亚麻籽冷榨饼为原料,采用真空冷冻干燥和喷雾干燥两种方式制备分离蛋白,研究两种干燥方式对亚麻籽分离蛋白功能性质的影响。结果表明:真空冷冻干燥亚麻籽分离蛋白的溶解性、持水性、吸油性、乳化性、乳化稳定性和泡沫稳定性均高于喷雾干燥亚麻籽分离蛋白,而后者的起泡性高于前者。在中性条件下真空冷冻干燥和喷雾干燥亚麻籽分离蛋白的持水性分别为6.75 g/g和5.74 g/g;亚麻籽分离蛋白吸油性较好,在30℃时,喷雾干燥亚麻籽分离蛋白的吸油性为1.91 g/g,冷冻干燥亚麻籽分离蛋白是其3.09倍。亚麻籽分离蛋白的持水性、乳化性和乳化稳定性随着p H的变化曲线与溶解性相似,均在p H 4时最小。     

高静压处理对大豆分离蛋白功能特性的改善

本文对经100～400MPa高静压处理后大豆分离蛋白溶液的溶解特性、乳化性能和起泡性能进行研究，探讨高静压处理对大豆分离蛋白特性的修饰效果。发现常温下，大豆分离蛋白溶液随处理压力的升高和处理时间的延长，其溶解性增大、乳化性能和起泡性能均提高。差示热扫描(DSC)显示高静压处理可提高大豆分离蛋白液的热稳定性和变性温度，经400MPa压力处理30min的大豆分离蛋白发生解离现象。     

不同干燥方法对大豆分离蛋白功能性质的影响

采用离心喷雾干燥、真空冷冻干燥、热风干燥、微波干燥对大豆分离蛋白进行干燥，研究干燥后的大豆分离蛋白的功能性质。结果表明：微波干燥的大豆分离蛋白粘度较大，而乳化性、吸水性、吸油性和水合能力小；热风干燥和喷雾干燥的大豆分离蛋白功能性质相似；真空冷冻干燥对大豆分离蛋白功能性质影响小。     

干热处理对大豆分离蛋白乳化与起泡性能的影响

研究了60℃、80℃和90℃下干热处理对大豆分离蛋白乳化和起泡性能的影响.研究发现,干热处理4 d使大豆分离蛋白的乳化活性增加到最大值,其乳化稳定性也增加到接近最大值的水平,长时间的热处理降低大豆分离蛋白的乳化活性;60℃干热处理1 d使大豆蛋白的膨胀率增加到最大值880%,此后随热处理时间的延长而持续下降,80℃和90℃热处理降低了大豆分离蛋白的泡沫稳定性;干热处理使大豆分离蛋白7S亚基各组分和部分11S酸挂亚基发生共价聚合形成高分子量的聚合物.     

大豆乳清蛋白功能特性的研究

对经过膜分离技术提取的大豆乳清蛋白的功能特性进行研究。主要研究了pH对大豆乳清蛋白的溶解特性、起泡性能及乳化性能的影响,并对大豆乳清蛋白的组成成分进行了电泳分析。结果表明,大豆乳清蛋白具有较好的溶解性及起泡性,但泡沫稳定性及乳化性不如大豆分离蛋白。大豆乳清蛋白主要包含6种成分。     

海藻酸钠接枝大豆分离蛋白改性产物功能特性的研究

为了进一步提高大豆分离蛋白的功能特性,采用糖基化方法对其进行改性。以大豆分离蛋白和海藻酸钠为主要原料,制备不同糖基化程度的大豆分离蛋白样品,以天然大豆分离蛋白为对照,对不同糖基化程度的大豆分离蛋白的功能特性进行了研究。研究结果显示：糖基化修饰可提高大豆分离蛋白的变性温度和变性焓变,且糖基化程度越大,变性温度和变性焓变值越高。在pH为8时,与天然大豆分离蛋白相比,糖基化大豆分离蛋白的溶解度可提高约29.4%,乳化能力可提高约84.6%,乳化稳定性可提高约13.5%,起泡能力可提高约3.1%,起泡稳定性可提高约8.5%。此外,一定程度的糖基化可以提高大豆分离蛋白的羟基自由基清除能力,当糖基化程度为27.1%时,清除羟自由基的能力最强。该研究结果可为优质大豆分离蛋白的生产提供理论基础。     

喷雾干燥与冷冻干燥鸡蛋粉特性研究

以鲜鸡蛋为原料,利用喷雾干燥和冷冻干燥技术制备鸡蛋粉,对比2种蛋粉水分含量、水分活度、溶解度、色差、微观结构等理化性质,同时检测起泡性、乳化性,并选用喷雾干燥蛋黄粉制备凝胶探讨功能特性。结果表明:喷雾干燥蛋粉和冷冻干燥的蛋粉水分含量、水分活度、溶解度和色差差异显著(P<0.05),且喷雾干燥蛋粉和冷冻干燥蛋粉起泡性及乳化性均在氯化钠浓度为0.5 g/100 mL时达到最大值;制备凝胶最佳条件为加水量为150%、氯化钠浓度为3%、温度100℃、热处理15 min。此项研究将对蛋粉的应用奠定理论基础。     

两种干燥方式对大豆分离蛋白凝胶强度影响

以自制脱脂大豆粕为原料制备大豆分离蛋白,重点探讨两种不同干燥方式对分离蛋白凝胶强度影响;经实验表明:冷冻干燥分离蛋白凝胶强度较高,并比喷雾干燥分离蛋白凝胶强度高出21.96%。     

The influence of additives and drying methods on quality attributes of fish protein powder made from saithe (Pollachius virens)

BACKGROUND: Fish protein powder (FPP) is used in the food industry for developing formulated food products. This study investigates the feasibility of increasing the value of saithe (Pollachius virens) by producing a functional FPP. Quality attributes of spray and freeze‐dried saithe surimi containing lyoprotectants were studied. A freeze‐dried saithe surimi without lyoprotectants was also prepared as a control sample. RESULTS: The amount of protein, moisture, fat and carbohydrate in the FPPs were 745–928, 39–58, 21–32 and 10–151 g kg^?1. Quality attributes of FPPs were influenced by the two drying methods and lyoprotectants. The highest level of lipid oxidation was found in the control and the second highest in the spray‐dried FPP. The spray‐dried fish protein had the lowest viscosity among all FPPs. Gel‐forming ability of samples with lyoprotectants was higher than that of the control. Water‐binding capacity, emulsion properties and solubility of the freeze‐dried fish protein containing lyoprotectants were significantly higher than spray‐dried and control samples. However, functional properties of spray‐dried FPP were higher than the control sample. CONCLUSION: It is feasible to develop value‐added FPP from saithe surimi using spray‐ and freeze‐drying processes, but freeze‐dried FPP containing lyoprotectant had superior functional properties and stability compared with spray‐dried sample. Both products might be used as functional protein ingredients in various food systems. Copyright © 2010 Society of Chemical Industry     

不同制备方式的鱼油微胶囊挥发性成分及贮藏稳定性的比较

本文研究了不同干燥工艺对鱼油和两种微胶囊挥发性成分以及贮藏稳定性的影响。以鱼油作为芯材,魔芋葡甘聚糖和大豆分离蛋白作为壁材,制备成纳米乳液后通过喷雾干燥和真空冷冻干燥工艺制备微胶囊。试验发现,鱼油、喷雾干燥微胶囊和冷冻干燥微胶囊共鉴定出80种挥发性风味物质,其中鱼油42种,喷雾干燥微胶囊41种,冷冻干燥微胶囊20种,共有成分包括十四烷酸乙酯、9-十六碳烯酸乙酯、1-甲基-4-异丙基苯和1-甲基-4-异丙基苯。加速贮藏实验中两种鱼油微胶囊的过氧化值（POV）增长速率均较鱼油低,当贮藏时间达到30 d时,鱼油、喷雾干燥微胶囊和真空冷冻干燥微胶囊POV值分别为15.65 mmol/kg、8.89 mmol/kg和8.14 mmol/kg,喷雾干燥所得鱼油微胶囊包埋率下降速率较冷冻干燥鱼油微胶囊快,包埋率分别为34.29%和40.90%。综合分析,两种鱼油微胶囊制备方法均能够延缓鱼油氧化和掩蔽不良风味,但冷冻干燥制备鱼油微胶囊更佳,对制备鱼油微胶囊具一定的参考意义。     

Production and Evaluation of Pea Protein Isolate

Laboratory and pilot plant processes were developed for producing pea protein isolate from field peas. Sodium proteinate and isoelectric products containing up to 90% protein were obtained by alkaline extraction and precipitation at the isoelectric point. Drying was carried out by freeze, spray and drum processes. Chemical analysis, functional properties, color and flavor of the dried isolates compared favorably with their soy counterparts. Generally, the sodium proteinates exhibited more functionality than isoelectric isolates. Drum drying decreased the nitrogen solubility index and increased water absorption. Freeze- and spray-drying resulted in isolates with the highest emulsification and water absorption values. Spray drying produced the best foaming, color and flavor properties.     

Functional properties of native and cheese whey protein concentrate powders

The objective of this study was to compare microfiltered native whey protein concentrate and traditional cheese whey protein concentrate powders and their functional properties. Solubility, viscosity, gelation, foaming properties, emulsification and water-holding capacity were studied. The effect of spray and freeze drying methods on functional properties was evaluated. Gel strength varied from 0.11 to 0.65 N. Foaming stability and overrun varied from 0 to 29.3 min and from 230 to 2200%, respectively. Foaming and gelation properties were clearly better with native whey protein powders. Differences between drying methods were not observed but higher heat load decreased solubility.     

干燥方式对四角蛤蜊酶解物功能特性和 抗氧化活性的影响

目的比较不同干燥方式对四角蛤蜊木瓜蛋白酶酶解物功能特性和抗氧化活性的影响。方法采用冷冻干燥和喷雾干燥2种方式对四角蛤蜊木瓜蛋白酶酶解物进行干燥处理,比较其功能特性和抗氧化活性。结果冷冻干燥(freezing drying,FD)组的蛋白含量(49.56%)高于喷雾干燥(spray drying,SD)组(44.31%),2组均含有17种氨基酸,总氨基酸含量之间无显著性差异。两者均具有一定的抗氧化能力,FD组的DPPH?清除能力和还原能力均优于SD组,其IC50和AC0.5值分别为3.02、4.52 mg/mL和3.55、4.03 mg/mL。FD组和SD组颜色差异显著,且FD组的溶解性、起泡性和泡沫稳定性均好于SD组。结论 FD组的功能特性和抗氧化活性均优于SD组,四角蛤蜊酶解物采用真空冷冻干燥效果更好。     

干燥方式对蛋清蛋白理化性质和功能特性的影响

为探究干燥方式对蛋清蛋白（egg white protein,EWP）功能特性的影响及其内在机理,分别通过喷雾干燥与真空冷冻干燥制备蛋清蛋白粉,并对其蛋白结构、理化性质与功能特性进行研究。结果表明,与蛋清液（EWP-C）相比,喷雾干燥使蛋清蛋白（EWP-P）的内源性荧光强度降低,表面疏水性和表面游离巯基含量增大。傅里叶变换红外光谱分析显示,EWP-P的α-螺旋、β-折叠和β-转角分别为16.30%、25.72%和40.23%,冷冻干燥蛋清蛋白（EWP-D）分别为20.43%、24.32%和35.69%。不同pH下,EWP-D的溶解度均高于EWP-P,表面张力小于EWP-P。此外,EWP-P的接触角为99.62°,高于EWP-D（接触角为65.97°）,表明喷雾干燥能显著提高蛋白的疏水性（P<0.05）。EWP-D在不同pH下的乳化性、乳化稳定性以及起泡性均大于EWP-P,但起泡稳定性更小,这与EWP-D较高的溶解性与较低的表明疏水性有关。荧光倒置显微镜及激光共聚焦扫描显微镜分析表明EWP-D乳液的微粒更小,分布更均匀,其稳定性高于EWP-P。综上,喷雾干燥蛋清蛋白的β-折叠结构较多,表面游离巯基含量和表面疏水性较高,具有较好的凝胶性;冷冻干燥蛋清蛋白的表面疏水性较小,且表面张力小、溶解度大,具有更好的乳化能力与起泡性。     

Characterisation of peanut protein concentrates from industrial aqueous extraction processing prepared by spray and freeze drying methods

Peanut protein concentrates (PPCs) were prepared by aqueous extraction processing (AEP), organic solvent extraction processing (SEP) and prepress-organic solvent extraction processing (P-SEP) and converted into powder by freeze and spray drying. The drying method showed an influence on the surface morphology and second structure of PPCs. Peanut protein concentrates of AEP were found to have lower protein contents, solubility and higher surface hydrophobicity, resulted in similar emulsion ability index (EAI) values and lower emulsion stability index (ESI) and water-holding capacity (WHC) values compared to PPCs of SEP and P-SEP. Foaming capacity was barely affected by oil extraction processing and drying methods, foaming stability was significantly influenced by oil extraction processing. Freeze-dried PPCs had higher solubility, WHC and fat absorption capacity than spray-dried PPCs, which was not the case for EAI and ESI. Hence, PPCs of AEP showed adequate functional properties, making AEP more appropriate for phytoprotein beverages.     

A comparative study of the functional properties of amaranth and soybean globulin isolates

The functional properties of the amaranth globulin isolate were determined and compared to those of the well studied soybean globulin isolate. Functional properties investigated included protein solubility, heat coagulation, foaming and emulsifying activity and stabilities, as well as fat binding. Overall, the amaranth globulin isolate was found to have significantly higher solubility (p ⪇ 0.05) i.e., 9 times higher, and higher heat stability (p ⪇ 0.05) in the vicinity of its isoelectric point, pH 5–6, than the corresponding soybean globulin isolate. Between pH 3–9 the amaranth globulin isolate was found to have significantly higher (p ⪇ 0.05) foaming capacities and stabilities than the soybean isolate. Maximum foaming capacity for the amaranth globulin was determined to occur around its isoelectric point. The emulsifying activity of the amaranth globulin isolate was found to be significantly higher (p ⪇ 0.05) between pH 3–9 than the corresponding soybean globulin isolate. The most substantial difference between the two isolates was that the amaranth isolate showed maximal emulsifying activity and stability at pH 7.0. Little difference was observed in the fat absorption capacities between the two prepared isolates. Nutritionally, the amaranth globulin isolate was found to be of superior quality compared to the soybean globulin isolate due to its higher content of essential amino acids. Overall, the functional properties of the amaranth globulin isolate were much better than the soybean isolate especially in the vicinity of its isoelectric point, suggesting a potential advantage if used in various thermally processed food formulations that fall within this pH range; a range where more common isolates perform very poorly.