分离技术在D90脱盐乳清液工业化生产中的集成应用

将膜分离技术、离子交换技术、电渗析技术集成应用于脱盐乳清生产线上,采用四因素五水平二次回归正交旋转组合实验设计,研究D90脱盐乳清液最佳优化工艺条件选择进料质量分数、进料温度、纳滤压力、电渗析温度进行单因素实验,并验证回归模型的显著性。结果表明,生产D90脱盐乳清液的最佳工艺条件:进料质量分数16.03%,进料温度11.59℃,纳滤压力2.56 MPa,电渗析温度36.79℃。     

大豆乳清废水膜过程生产低聚糖工艺研究

主要探讨了乳清废水膜过程生产低聚糖等产品工艺中各级膜滤过程和其他流程试验,采用正交试验确定了低聚糖液的活性炭最佳脱色条件:脱色时间30 min,加炭量2.0%,脱色温度70℃,pH4.0,同时还对脱色后的低聚糖液的树脂脱盐试验进行了研究.乳清废水经过该工艺过程,最终形成了大豆低聚糖产品,超过了主产品的效益,水质接近纯净水并回用至工序中.     

响应面法优化乳清梨酒发酵工艺的研究

以乳清粉作为试验原料,通过单因素试验研究了酵母菌接种量、发酵温度、发酵时间、蔗糖添加量对乳清梨酒发酵的影响,并且借助响应面设计,对乳清梨酒发酵工艺进行了优化。结果表明,乳清梨酒最佳发酵条件为接种量6%、发酵温度28 ℃、发酵时间79 h。在此最佳条件下,乳清梨酒酒精度为8.10%vol,酸度17.72 g/L。乳清梨酒呈淡黄绿色,酒香清雅,酒体醇厚,酸甜爽口。     

碎米葡萄糖硼酸盐分离法制备高果糖浆的研究

研究以碎米葡萄糖为原料,硼酸盐分离法制备高果糖浆并用大孔树脂脱硼的工艺。通过单因素与正交试验,获取制备高果糖浆的最佳工艺为:糖液浓度20%、异构酶加酶量0.3%、硼酸添加量0.2%、pH7.5、反应温度60℃、反应时间21h;获取碎米高果糖浆脱硼的最佳工艺为:上样浓度为30%、吸附流速4mL/min、温度70℃、进料量40mL。在此条件下高果糖浆的果糖含量用高效液相测得为77.5%,硼酸含量为1.98%。     

顺序式模拟移动色谱分离木糖醇母液的前处理工艺研究

以木糖醇母液为研究对象,研究顺序式模拟移动色谱分离木糖醇母液的前处理工艺。利用单因素与响应面法对木糖醇母液的前处理工艺进行优化,在单因素试验基础上,考察活性炭添加量、脱色温度、脱色时间、脱盐方式等因素对木糖醇母液脱色率的影响,再根据Box-Behnken试验设计原理,采用响应面方法优化木糖醇母液脱色条件,考察离子交换脱盐的顺序与洗脱流速对木糖醇母液脱盐的影响。结果显示:顺序式模拟移动色谱分离木糖醇母液的前处理工艺参数为:木糖醇母液浓度为25%,活性炭添加量3.71%,脱色温度59℃,脱色时间1.77h,木糖醇母液的脱色率达到93.5±0.5%。离子交换脱盐的顺序为阴-阳-阴,洗脱流速为30m L/min,母液的电导率为25.5±0.5μS/cm。经本工艺处理得到木糖醇母液达到了顺序式模拟移动床分离木糖醇母液的进料要求。     

电渗析技术在鲍鱼内脏鱼酱油脱盐中的应用

传统发酵的鱼酱油,含盐量较高,不符合现代健康的饮食方式,长期食用会增加患高血压等疾病的风险。利用电渗析技术对鱼酱油进行脱盐处理,在降低鱼酱油盐含量的同时,还可以最大限度地保留其原有的风味和营养价值。本研究以脱盐率和氨基酸回收率为主要指标,通过单因素试验分别考察电压、流量、鱼酱油盐含量3个因素对电渗析脱盐过程的影响。单因素试验结果表明,鲍鱼内脏鱼酱油的最佳脱盐方案是:操作电压20 V,操作流量40 L/h,盐含量5.14%。进一步通过正交试验优化,确定了最佳工艺条件,即操作电压20 V,操作流量35L/h,鱼酱油盐含量5.14%。结果表明,通过最佳的工艺条件进行脱盐,可以成功脱去鲍鱼内脏鱼酱油中80.72%的盐,保留91.66%的氨基酸。     

酱油脱盐新工艺的研究

该研究以氨基酸态氮损失率及脱盐率作为主要指标,对比电渗析和纳滤两种工艺对酱油的脱盐效果。经过单因素试验,确定两种工艺的最佳参数:纳滤脱盐工艺,操作压力为2.6MPa,加入35%纯水,平均通量为14.2L/(m~2·h),AN损失率为11.5%;加入55%纯水,平均通量为26.4L/(m~2·h),AN损失率为17.1%;电渗析采取稳压模式,18V电压,电渗析脱盐至12%、9%时,AN损失率分别为4%、5.1%。纳滤脱盐投资低,但有效成分损失较多,电渗析脱盐可以提高酱油品质,但前期投资和运行成本较高,两种工艺为酱油脱盐提供了不同的选择方案。     

响应面法优化高盐腌长白楤木嫩芽脱盐工艺

以感官评分和含盐量为评价指标,通过单因素试验和响应面法,研究液料比、脱盐时间、脱盐温度、换水次数4个因素对高盐腌制长白楤木嫩芽脱盐效果的影响。结果表明,最佳脱盐工艺条件为:液料比3∶1(mL/g)、脱盐时间20 min、脱盐温度30℃、换水次数2次。在此条件下,脱盐后的长白楤木嫩芽含盐量降为4.027%,质地嫩脆,且具有长白楤木嫩芽独特的浓郁香味,感官质量最佳。     

维生素B2微胶囊制备工艺的优化

以阿拉伯胶为壁材,采用喷雾干燥法制备维生素B_2微胶囊,研究了壁芯比、壁材浓度、进风温度、进料流速四因素对微胶囊包埋率的影响。通过单因素试验和正交试验得到微胶囊的最佳工艺条件为:壁芯比为10:1、壁材浓度为20%、进风温度为170℃、进料流速为3 mL/min,该条件下维生素B_2微胶囊的包埋率为86.12%。     

响应面试验优化盐渍仿刺参脱盐工艺

为了提高脱盐速率和减少营养损失,以盐渍仿刺参为原料,采用常压静水脱盐方式,研究了温度、料液比、脱盐时间、换水次数对脱盐效果的影响,通过单因素和响应面法对影响盐渍仿刺参脱盐工艺的主要因素进行分析优化。结果表明:在相同的脱盐温度下,影响盐渍仿刺参脱盐工艺的因素按主次顺序排列为:料液比脱盐时间换水次数;确定了盐渍仿刺参脱盐的最佳工艺条件为:脱盐温度25℃,料液比1∶4.3 g/m L,换水次数2,每隔240 min进行换水,在此条件下测得脱盐率可达到85.98%±0.22%,与预测值吻合度好。     

Feasibility of using electrodialysis with bipolar membranes to deacidify acid whey

A nonreagent method for the regulation of the pH of acid whey was investigated at a laboratory scale. Acid whey and concentrated acid whey were subjected to electrodialysis with bipolar membranes in order to raise the pH value to 6.5. Demineralised whey underwent identical processing. The deacidification rate as per tonne of a dry matter was similar for acid whey and concentrated acid whey treatment at 70% and 90% degrees of demineralisation. We estimated the energy consumption of electrodialysis. The preliminary demineralisation of whey significantly increased the energy efficiency of whey pH correction. Additionally, we observed substantial fouling on the diluate side of bipolar membranes after whey treatment.     

Cottage Cheese Whey Ultrafiltrate Produced by Hollow Fiber Ultrafiltration,

The composition and volume of ultrafiltrate produced by hollow fiber ultrafiltration of cottage cheese whey with the Bio-Rad Bio-Fiber 50 Miniplant were studied and fitted to models. Temperature, pH, and protein concentration of the feed cheese whey, the flow rate of the feed cheese whey through the Miniplant, and the pressure differential across the membranes were the independent variables in the model fitting. Feed whey temperature and pressure differential across the membranes were the most significant variables affecting the volume of ultrafiltrate produced. Surface plots of response were generated.     

植物乳杆菌微胶囊化研究

为保护植物乳杆菌的活性以增强乳杆菌在动物肠道内的益生功能,以天然发酵玉米青贮饲料中优良植物乳杆菌作为芯材,乳清蛋白和明胶为壁材,利用喷雾干燥法制成微胶囊,并以植物乳杆菌包埋率为响应值,研究壁材配比、壁材添加量、进风温度、进料量4个因素,进行中心组合实验(Box-Behnken),通过响应面分析对喷雾干燥法制备植物乳杆菌微胶囊条件进行优化。结果表明:最优条件为壁材配比(乳清蛋白与明胶质量比)1:2、壁材添加量22%、进风温度127℃、进料量35%,在此条件下,植物乳杆菌包埋率为62.15%。结论:本研究为应用喷雾干燥法制备植物乳杆菌微胶囊奠定了基础。     

酶解乳清蛋白制备降胆固醇活性肽的工艺研究

利用生物酶技术酶解乳清蛋白,制备具有降胆固醇活性的多肽,通过响应面试验、二次旋转回归设计建立回归模型,以胆固醇胶束溶解度抑制率为评价指标,对乳清蛋白的酶解条件进行了优化。结果表明,乳清蛋白的最佳酶解条件为：酶解时间8.5 h、酶解温度55 ℃、酶解pH 8.0、加酶量4.7%、乳清蛋白含量5.8%,在此条件下,酶解乳清蛋白得到的活性肽的胆固醇胶束溶解度抑制率为18.21%。     

Determination of orotic acid in whey and modified whey products

The concentration of orotic acid in dry whey ranged between 64 and 146 mg/100 g and appeared dependent on whey type. The orotic acid of modified whey products, prepared commercially by electrodialysis, ultrafiltration, gel filtration, or polyphosphate precipitation was between 7 and 124 mg/100 g, which was less than that of dry whey. It appears that whey processing methods do not concentrate orotic acid in whey fractions.     

The Effect of Feed Solids Concentration and Inlet Temperature on the Flavor of Spray Dried Whey Protein Concentrate

Previous research has demonstrated that unit operations in whey protein manufacture promote off‐flavor production in whey protein. The objective of this study was to determine the effects of feed solids concentration in liquid retentate and spray drier inlet temperature on the flavor of dried whey protein concentrate (WPC). Cheddar cheese whey was manufactured, fat‐separated, pasteurized, bleached (250 ppm hydrogen peroxide), and ultrafiltered (UF) to obtain WPC80 retentate (25% solids, wt/wt). The liquid retentate was then diluted with deionized water to the following solids concentrations: 25%, 18%, and 10%. Each of the treatments was then spray dried at the following temperatures: 180 °C, 200 °C, and 220 °C. The experiment was replicated 3 times. Flavor of the WPC80 was evaluated by sensory and instrumental analyses. Particle size and surface free fat were also analyzed. Both main effects (solids concentration and inlet temperature) and interactions were investigated. WPC80 spray dried at 10% feed solids concentration had increased surface free fat, increased intensities of overall aroma, cabbage and cardboard flavors and increased concentrations of pentanal, hexanal, heptanal, decanal, (E)2‐decenal, DMTS, DMDS, and 2,4‐decadienal (P < 0.05) compared to WPC80 spray dried at 25% feed solids. Product spray dried at lower inlet temperature also had increased surface free fat and increased intensity of cardboard flavor and increased concentrations of pentanal, (Z)4‐heptenal, nonanal, decanal, 2,4‐nonadienal, 2,4‐decadienal, and 2‐ and 3‐methyl butanal (P < 0.05) compared to product spray dried at higher inlet temperature. Particle size was higher for powders from increased feed solids concentration and increased inlet temperature (P < 0.05). An increase in feed solids concentration in the liquid retentate and inlet temperature within the parameters evaluated decreased off‐flavor intensity in the resulting WPC80.     

氨基酸溶液电渗析脱盐过程的研究

测定了不同浓度和流速下的盐水和氨基酸盐溶液的极限电流密度,分析了浓度、流速、氨基酸含量等因素对电渗析极限电流密度的影响,提出了描述电渗析特性的数学模型。初步研究了应用电渗析对氨基酸盐溶液进行处理时,流速和电压对脱盐率和氨基酸回收率的影响,用较低的流速在接近极限电流密度的条件下操作能达到最好的分离效果。     

Optimisation of process parameters to develop nutritionally rich spray‐dried honey powder with vitamin C content and antioxidant properties

The aim of present research was to optimise the conditions to develop nutritionally rich honey powder using honey, whey protein concentrate (WPC), aonla (Emblica officinalis. Gaertn) and basil (Ocimum sanctum) extract with the help of co‐current spray drier. Response surface methodology was applied to study the effects of inlet temperature (160–180 °C), whey protein concentrate (25–35%), feed flow rate (0.08–0.13 mL s^?1), aonla extract (6–8%) and basil extract (6–8%) on product responses, viz. bulk density, hygroscopicity, antioxidant activity (AOA), total phenolic content (TPC) and vitamin C. Statistical analysis revealed that independent variables significantly affected all the responses. The results demonstrated that increasing inlet temperature lowered the bulk density, hygroscopicity, AOA, TPC and vitamin C, whereas addition of aonla extract and basil extract increased the AOA (82.73%), TPC (63.27%) and total vitamin C content (94.89%) as these functional compounds were encapsulated by WPC. Similarly, with increase in feed flow rate and WPC, there was increase and decrease in the bulk density and hygroscopicity, respectively. The recommended optimum spray‐drying conditions were inlet air temperature (170 °C), feed rate (0.11 mL s^?1), whey protein concentrate (35%), aonla (8%) and basil extract (6%).     

How electrodialysis configuration influences acid whey deacidification and membrane scaling

With the rising popularity of Greek-style yogurts in the past few years, the production of acid whey has drastically increased. If sweet whey is usually further processed, the acid whey valorization comes with challenges because its drying is jeopardized by its high mineral and organic acid contents. For this reason, prior demineralization and deacidification are usually performed at industrial scale using a combination of ion exchange resins and electrodialysis. This whole process represents large amounts of resources and energy consumption as well as an important production of effluents. The optimization of the electrodialysis technique, currently the focus of a few studies, could result in the replacement of the serial processes and would provide a cost-effective and eco-efficient alternative. In this work, the demineralization and deacidification of acid whey were compared via 2 electrodialysis configurations: one conventional and one using bipolar membranes. Both configurations allowed to reach interesting demineralization (67%) and deacidification (44%) rates. However, even though the appearance of fouling or scaling has never been reported, scalings of different natures were observed on membranes using both configurations. Amorphous calcium phosphate was identified on the anion exchange membranes for both configurations while calcite and brucite were identified on cation exchange ones using the bipolar membrane configuration. These scaling formations were linked to the migration of divalent ions and water splitting phenomenon caused by a high demineralization rate or by an already formed significant scaling.     

REVERSE OSMOSIS OF COTTAGE CHEESE WHEY. 1. Influence of Composition of the Feed

SUMMARY– Permeation rate, retention, and solute flux during reverse osmosis of whey and whey fractions were compared using two types of cellulose acetate membranes. When the feed solutions contained no molecules larger than lactose, concentration polarization had little influence on performance except at the highest available driving force (applied pressure minus difference between osmotic pressures of the feed and permeate = 37.8 atm). With the more complex feeds (whey and deproteinized whey), both concentration polarization and fouling of the membrane occurred. Concentration polarization decreased both permeation rate and retention. Fouling decreased permeation rate, but its influence on retention was variable and depended principally on the feed, the solute, and the available driving force. Proteins and other macromolecules in whey had a greater influence on performance during reverse osmosis than smaller solute molecules. With whey as feed, maximum permeation rates were achieved at low available driving forces (10-12 atm), and were similar for the two types of membranes (about 1 ml/cm²*sec). Increasing the available driving force increased retention and therefore reduced solute flux. Choice between the two membranes requires a compromise between extent of desalting and loss of lactose in the permeate.