经酶法改性的大豆分离蛋白作为壁材微胶囊化海豹油的研究

传统方法以天然大豆分离蛋白(SPI)作为壁材的微胶囊对芯材的包埋性不够理想,微胶囊表面有很多凹陷。本文采用经酶法改性的SPI作为壁材的主要原料对海豹油进行微胶囊化,通过单因素和正交试验研究了最佳壁材组合为:总固形物浓度25%、芯材/壁材30%、明胶/麦芽糊精(MD)1+3、乳化剂用量1.25%,在最优组合下所得微胶囊化产率为94.5%,效率为94.9%。所得产品形状有规则,表面无裂纹及凹陷,贮藏试验表明微胶囊的贮存稳定性大为改善。     

酶改性大豆分离蛋白作为壁材微胶囊化海豹油研究

传统以天然大豆分离蛋白(SPI)作为壁材微胶囊对芯材包埋性不够理想,微胶囊表面有很多凹陷。该研究采用经酶法改性SPI作为壁材主要原料对海豹油进行微胶囊化,通过单因素和正交实验研究最佳壁材组合为:总固形物浓度25％、芯材／壁材30％、明胶／麦芽糊精(MD)1+3、乳化剂用量1．25％,在最优组合下所得微胶囊化产率为94．5％,效率为94．9％;所得产品形状有规则,表面无裂纹及凹陷,贮藏实验表明,微胶囊贮存稳定性大为改善。     

大豆蛋白酶解产物的微胶囊化及理化性质表征

令人难以接受的苦味和较强的吸湿性是限制大豆蛋白肽成为高品质食源肽的重要因素。本研究以大豆蛋白酶解产物(SPH)为芯材,以大豆蛋白(SPI)-大豆多糖(SPSS)复合物为壁材,通过喷雾干燥技术制备大豆蛋白酶解产物微胶囊,优化其工艺,并对微胶囊产品理化性质进行表征。结果表明,微胶囊的芯材/壁材比例为1/4,壁材比例(SPI/SPSS)为2/1,微胶囊具有最佳的大豆蛋白酶解产物包埋效果,包埋率达50.92%、苦味降低2.68倍、吸湿性降低1.61倍。透射电镜结果显示,微胶囊呈球型,表面光滑、连续,无孔洞或裂缝。红外分析结果证实SPI与SSPS之间发生了静电相互作用。大豆多糖与大豆蛋白因其大分子结构,组合使用能提升包埋的结构稳定性,也为SPH微胶囊产品作为功能性配料提供一定理论基础。     

经酶法改性的大豆分离蛋白作为壁材微胶囊化海豹油的研究

传统方法以天然大豆分离蛋白（SPI）作为壁材的微胶囊对芯材的包埋性不够理想，微胶囊表面有很多凹陷。本文采用经酶法改性的SPI作为壁材的主要原料时海豹油进行微肢囊化，通过单因素和正交试验研究了最佳壁材组合为：总固形物浓度25％、芯材／壁材30％、明胶／麦芽糊精（MD）1＋3、乳化荆用量1.25％，在最优组合下所得微胶囊化产率为94．5％，效率为94．9％。所得产品形状有规则。表面无裂纹及凹陷，贮藏试验表明微肢囊的贮存稳定性大为改善。     

乳蛋白微胶囊包埋共轭亚油酸及其稳定性研究

目的比较不同乳蛋白作为微胶囊壁材包埋共轭亚油酸的效果,并考察其产品的稳定性。方法分别以牛乳浓缩蛋白MPC80(milk protein concentrate,MPC)和乳清浓缩蛋白WPC80(whey protein concentrate,WPC)为高蛋白壁材,以多不饱和脂肪酸(共轭亚油酸,conjugated linoleic acid,CLA)为芯材,制备微胶囊产品。在芯壁比(芯材和壁材质量比)分别为1:4和1:8的比例下将壁材溶液(蛋白浓度为16%)和芯材混合、均质,经由喷雾干燥制备了共轭亚油酸微胶囊产品。通过扫描电子显微镜和气相色谱等检测方法对微胶囊产品的包埋率、表面形貌以及储藏过程中芯材的氧化稳定性进行研究。结果当芯壁比相同时(1:4和1:8,m:m),MPC组微胶囊的芯材包埋率总是低于WPC组;且MPC组微胶囊产品的表面凹陷程度和内壁疏松程度也更高。当芯壁比提高后,WPC和MPC组的微胶囊效率均有所上升。但是对不同芯壁比的微胶囊产品进行氧化稳定性检测后发现,加速储藏(45℃)过程中MPC组微胶囊产品的质量都比WPC组差。结论牛乳蛋白种类对牛乳蛋白作为CLA微胶囊壁材的影响较大。WPC是CLA微胶囊的优质壁材,而MPC虽然可以作为微胶囊壁材应用,但是对敏感芯材CLA的包埋效率和保护效果都存在一定的局限性,需要进一步改善以提高其应用性能。     

不同壁材组合油茶籽油微胶囊的性能研究

研究了以大豆分离蛋白、麦芽糊精、壳聚糖、阿拉伯胶为壁材,通过复配组合,采取喷雾干燥法制备油茶籽油微胶囊产品,并以乳化稳定性、微胶囊化效率及产率、微胶囊质量评价、微胶囊的形态和微胶囊氧化稳定性为评定指标,比较不同壁材组合得到的产品之间的差异.结果表明,以大豆分离蛋白与麦芽糊精为组合壁材的油茶籽油微胶囊产品具有良好的冲调性和氧化稳定性,较高的微胶囊化效率及理想的颗粒形态和粒径,是适宜喷雾干燥制备油茶耔油微胶囊产品的理想壁材组合之一.     

不同壁材制备油茶籽油微胶囊的研究

研究以大豆分离蛋白、酪朊酸钠、麦芽糊精、大豆膳食纤维和阿拉伯胶为壁材,通过复配组合,利用喷雾干燥法制备油茶籽油微胶囊产品,同时以乳化稳定性、微胶囊化效率和产率、微胶囊形态的微观表征颗粒完整率和微胶囊感官品质评价为评定指标,比较不同壁材组合得到的微胶囊产品之间的差异。结果表明,以大豆分离蛋白、酪朊酸钠和麦芽糊精为复配壁材的油茶籽油微胶囊产品为乳白色粉末,具有良好冲调性和流动性,微胶囊化效率83.62%和产率63.87%,微胶囊形态的颗粒完整率接近70%,是较好的喷雾干燥制备油茶籽油微胶囊产品的复配壁材之一。     

粉末大豆色拉油的制备

以麦芽糊精(MD)、水解大豆蛋白(SPH)、乳化剂、稳定剂等作为微胶囊壁材,利用喷雾干燥法制备粉末大豆色拉油,结果表明:SPH:MD为1:1,最适稳定剂为琼脂,其添加量为0.1%(占总固形物,W/W),吐温-80、单甘酯复配作乳化剂,用量为0.4%,制得的粉末大豆色拉油包埋效率达75.6%,产率可达98.1%,水溶性良好.     

扁杏仁油微胶囊的制备及质量评价

以魔芋胶(KGM)和大豆分离蛋白(SPI)为壁材,分子蒸馏单甘酯(GMS)为乳化剂,应用响应面分析法进行配方优化,以喷雾干燥法制备了扁杏仁油微胶囊,并对扁杏仁油微胶囊的包埋率、抗氧化性、微观结构进行测试。结果表明:扁杏仁油微胶囊最佳配方是扁杏仁油质量分数27%,魔芋胶质量分数2.8%,分子蒸馏单甘酯质量分数1.8%,大豆分离蛋白质量分数68.4%,制得的扁杏仁油微胶囊包埋率达到93.9%。产品表面光滑,粒径均匀,具有抗氧化稳定性。      

扁杏仁油微胶囊的制备及质量评价

以魔芋胶(KGM)和大豆分离蛋白(SPI)为壁材,分子蒸馏单甘酯(GMS)为乳化剂,应用响应面分析法进行配方优化,以喷雾干燥法制备了扁杏仁油微胶囊,并对扁杏仁油微胶囊的包埋率、抗氧化性、微观结构进行测试。结果表明:扁杏仁油微胶囊最佳配方是扁杏仁油质量分数27%,魔芋胶质量分数2.8%,分子蒸馏单甘酯质量分数1.8%,大豆分离蛋白质量分数68.4%,制得的扁杏仁油微胶囊包埋率达到93.9%。产品表面光滑,粒径均匀,具有抗氧化稳定性。     

酶法改性对各种蛋白膜的溶解特性和体外消化率的影响

以大豆分离蛋白SPI-1、大豆分离蛋白SPI-2、酪蛋白酸钠NaCas-1、酪蛋白酸钠NaCas-2、明胶G-1、明胶G-2、乳清蛋白浓缩物WPC、小麦面筋蛋白WG、花生分离蛋白PPI这9种蛋白质为原料制备蛋白膜,主要研究了谷氨酰胺转移酶(TGase)改性对这9种蛋白膜的溶解特性和体外消化率这2种性能的影响。TGase的作用使SPI-1膜、NaCas膜和WPC膜的水分含量呈显著性降低(P≤0.05)。TGase的处理使各种蛋白质膜的总可溶性物质量均比对照膜明显降低,SDS-PAGE分析表明,TGase作用明显降低了这几种蛋白膜在水溶液中的溶解性。与对照膜相比,TGase改性显著降低了蛋白膜的消化率,其中NaCas、SPI和G蛋白膜的下降幅度较大。这可能是因为TGase催化改性的蛋白膜中产生了新的交联。     

Heat-induced Gelation Properties of Salt-Soluble Muscle Proteins as Affected by Non-Meat Proteins

Addition of whey protein concentrate (WPC), whey protein isolate (WPI) or soy protein isolate (SPI) to salt-soluble muscle proteins (SSP) decreased the gel strength. WPI:SSP gels had higher water-holding capacity than SSP, SSP:WPC or SSP:SPI gels. Myosin heavy chain was a principal contributor to gel network formation in SSP, SSP:WPC, SSP:WPI and SSP:SPI systems. The characteristic fibrous network formed by SSP was the dominant feature of the microstructure of SSP:WPC and SSP:WPI gels. SSP:SPI gels had a more aggregated appearance due to the occurrence of clusters of SPI throughout the gel matrix.     

Morphology, proliferation, and ribonucleic acid and fractional protein syntheses in the small intestinal mucosa of young goats fed soy protein-based diets with or without amino acid supplementation

The study was designed to examine whether feeding soy protein isolate as partial replacement of casein (CN) affects jejunal protein synthesis and whether effects may be ameliorated by supplementation of those AA known to be at lower concentrations in soy protein isolate than in CN. Goat kids (14 d) were fed comparable milk protein diets, in which 50% of the crude protein was CN (CAS), soy protein isolate (SPI), or soy protein isolate supplemented with AA (SPIA) for 43 d (n = 8 per group). On d 42, plasma concentrations of protein, urea, and AA were measured before and after morning feeding. In the morning of d 43, [¹⁵N]RNA from yeast [13 mg/kg of body weight (BW)] was given with the diet to measure the reutilization of dietary RNA precursors for mucosal RNA biosynthesis. Four hours later, an oral dose of l-[1-¹³C]leucine (180 mg/kg of BW) was administered and blood samples were collected between −15 and +45 min relative to tracer administration for analysis of plasma ¹³C α-ketoisocaproic acid and ¹³C recovery in blood CO₂. Kids were killed 60 min after the tracer application, and jejunal tissue was collected to determine mucosal morphology, cell proliferation, enzyme activities, RNA synthesis, and fractional protein synthesis rate. Plasma protein concentrations were higher in CAS than in SPI and SPIA. Plasma concentrations of Thr were higher in CAS than in SPI and SPIA, and those of Met were lower in SPI than in CAS and SPIA. In mid-jejunum, villus circumferences were higher in CAS than in SPI and SPIA, and villus height and villus height:crypt depth ratio were higher in CAS than in SPI. In mid-jejunum, mucosal protein concentrations were higher in CAS than in SPI and SPIA and mucosal activities of aminopeptidase N tended to be higher in CAS than in SPI, whereas activities of dipeptidyl peptidase IV tended to be lower in SPI than in SPIA. Activities of 5′ nucleotidase and xanthine oxidase were lower in CAS than in SPI. The ¹³C recovery in blood CO₂ tended to be higher in SPI than in CAS. In mid-jejunum, ¹⁵N enrichment of RNA tended to be higher in CAS than in SPI, and ¹³C enrichment of protein-bound Leu was higher in SPI than in CAS. In mid-jejunum, the fractional protein synthesis rate tended to be higher in SPI than in CAS. Our results revealed changes in intestinal growth after soy protein feeding that were associated with effects on intestinal RNA and protein synthesis but that were not ameliorated by AA supplementation.     

SPI与SPH及其复配产物对面团特性和面条品质的影响机制

为提高面制品的营养品质,研究并比较了添加大豆分离蛋白(soy protein isolate,SPI)、大豆水解蛋白(soy protein hydrolyzates,SPH,水解度为4.54%)以及SPI和SPH复配产物(SPI-SPH)的混合粉的面筋特性和粉质特性,面团的动态流变学特性、蛋白质组分、二硫键和非共价键变化,以及面条的品质变化。添加SPI后面粉的湿面筋含量升高,干面筋含量下降,面筋指数降低,粉质特性评价值升高;面团的醇溶蛋白和麦谷蛋白含量增加,黏弹性增大,弹性比例增加。添加SPI-SPH的面粉面筋特性和面团特性变化趋势与添加SPI的面粉一致,其粉质特性评价值增大。添加SPH的面粉中无面筋洗出,粉质特性评价值升高;面团盐溶蛋白含量显著增加(P<0.05),弹性比例降低。添加大豆蛋白的面团中二硫键含量均增加,疏水相互作用减弱,氢键增强。与原面粉面条相比,SPI面条的硬度增大10.82%,SPI-SPH和SPH面条的弹性分别减小7.23%和6.02%,且添加SPH后面条的蛋白质保留率由93.02%降至87.31%。研究表明,大豆蛋白与面筋蛋白通过二硫键交联以及非共价键相互作用,阻碍面筋网络形成,破坏了面筋网络的连续性。并且,SPI和SPH复配在一定程度上减弱了SPH对面筋的弱化作用。     

Comparing the heat stability of soya protein and milk whey protein emulsions

The heat stability of emulsions stabilized by WPC or SPI or mixtures of the two are compared by following the change in oil droplet number during heating, and applying kinetic rate equations to calculate the rate constant (k) for destabilization. SPI emulsions were found to be unstable to heat at pH around the pI, whilst being stable at pH further from the pI. This is related to the pH dependent solubility of soy proteins. This determined that a pH close to the pI (pH 4.5) be used for further studies so as to give a heat labile emulsion. Both WPC and SPI emulsions showed a weak dependence of k on protein concentration at pH 4.5, and an increasing k as the temperature increased. Arrhenius plots for emulsions made with WPC were bilinear, whilst those for SPI followed a single straight line. The change in slope of the Arrhenius plots for the WPC emulsions occurred around 70 °C, lower than would be expected from the denaturation temperature of β-lactoglobulin, the protein that dominates the thermal behaviour of WPC. The activation energies for WPC and SPI emulsions calculated from the slopes of the Arrhenius plots are slightly lower for WPC and considerably lower for SPI than the equivalent values in the literature for these proteins in solution. This, and the apparent lower denaturation temperature of β-lactoglobulin in emulsions, we explain by hypothesizing that the WPC and SPI proteins are already partially denatured by surface adsorption when they are heated, and thus require less energy to denature, and unfold at lower temperatures than native non-adsorbed proteins.     

添加非肌肉蛋白对鱼糜制品品质影响的初步研究

实验采用质构分析法、色差分析法及感官评价法研究了大豆分离蛋白(SPI)、谷朊粉(GP)、乳清浓缩蛋白(WPC)对鱼糜制品品质的影响。结果表明:添加一定量的3种非肌肉蛋白可以明显地提高鱼糜制品的破断强度、凝胶强度、持水性和口感,但均降低了制品的凹陷深度和白度。以凝胶强度为优化值对3种非肌肉蛋白进行响应面优化后,确定了鱼糜制品的蛋白添加条件为:SPI 9.7%、GP 9.9%、WPC 7.6%,实际凝胶强度为(3 855.012±260.682)g.mm。     

大豆分离蛋白/可溶性大豆多糖作为生物活性物质包埋载体的研究进展

目前大豆分离蛋白(soy protein isolate,SPI)和可溶性大豆多糖(soluble soy polysaccharide,SSPS)均已实现工业化生产,在食品领域中得到了广泛的应用.作为生物大分子物质,以SPI和SSPS为壁材来包埋疏水性小分子生物活性物质受到众多学者的关注.以姜黄素为代表的疏水性小分子...     

大豆分离蛋白对大豆肽纳米颗粒Pickering乳液性能的影响

为提高大豆肽纳米颗粒(SPN)Pickering乳液稳定性,以大豆肽聚集体为原料,采用超声法制备SPN,对超声时间进行了优化;在SPN体系中引入大豆分离蛋白(SPI)构建复合乳化剂,研究不同乳化剂质量浓度下SPI对SPN界面活性和乳化稳定性的影响。结果表明：选取超声时间10 min制备SPN;随着乳化剂质量浓度的增大,乳液粒径逐渐减小,当乳化剂质量浓度较低(5 mg/mL)时,乳液出现桥联,乳化剂质量浓度过高(30 mg/mL)时则出现絮凝;界面蛋白吸附率随着乳化剂质量浓度的增加呈现先升高后降低的趋势。在相同乳化剂质量浓度下,添加SPI的SPN乳液(SPI-SPN乳液)的粒径分布峰左移,其粒径、界面蛋白吸附率显著小于SPN乳液的;在储存过程中,SPN乳液粒径逐渐增大,SPI-SPN乳液粒径没有显著变化;SPI-SPN乳液的乳析指数小于相同乳化剂质量浓度的SPN乳液,当乳化剂质量浓度为30 mg/mL时,储存15 d SPI-SPN乳液未出现分层现象。综上,SPI可以提高SPN的界面活性和SPN乳液储存过程中的絮凝稳定性和分层稳定性。     

大豆分离蛋白联合海藻酸钠制备番茄红素胶束

采用大豆分离蛋白-海藻酸钠共聚物（soy protein isolate-sodium alginate,SPI-SA）和大豆分离蛋白＋海藻酸钠混合物（SPI＋SA）分别制备番茄红素胶束,并考察了番茄红素胶束的稳定性和消化释放特性。结果表明：SPI-SA与SPI＋SA对番茄红素的包封效果相当;而SPI-SA胶束的抗氧化能力及稳定性均优于SPI＋SA胶束;经模拟胃肠消化SPI-SA和SPI＋SA制备的番茄红素胶束均具有较好的缓释效果。故SPI-SA可作为新型壁材对番茄红素进行包埋,生产新型保健品。     

Effects of foaming agents and foam density on drying characteristics and textural property of banana foams

The technique of foaming has proved effective in creating a porous structure, which is an important requirement for crisp food. Foam density and the type of foaming agent indeed play a key role in determining the drying kinetics and textural property of the foamed food. The influences of the foam density and the types of foaming agents on the moisture diffusivity as well as the quality in terms of microstructure, texture and volatile losses of banana foams were therefore investigated. Three foaming agents, i.e., fresh egg albumen (EA), soy protein isolate (SPI) and whey protein concentrate (WPC) were used. The experimental results showed that WPC banana foam could retain more open structure during drying. This morphology provided less shrinkage and led to higher values of the effective diffusivity as compared with that of SPI and EA banana foams. In terms of the textural properties, WPC and EA banana foams were spongy and less crisp than SPI banana foam. Samples with lower foam densities exhibited higher values of the effective diffusivity, smaller hardness and lower crispness than those with higher foam densities. The losses of volatile substances were substantial during all processing steps, but the major losses were during the foaming step.