副干酪乳杆菌海藻酸钠微胶囊包埋工艺

研究副干酪乳杆菌海藻酸钠微胶囊的包埋效果,副干酪乳杆菌在冻干、贮藏及模拟胃胀道环境中的存活情况,并优化包埋工艺参数。结果表明,大豆蛋白分离物(SPI)是适宜的内层壁材,低聚异麦芽糖对副干酪乳杆菌的冷冻保护效果最佳。当SPI用量为3%,低聚异麦芽糖添加量5%,海藻酸钠浓度2%、氯化钙浓度为0.2 mo L/L,副干酪乳杆菌的包埋率可达93.31%,冷冻干燥后微胶囊4℃储存28 d的副干酪乳杆菌存活率达58.97%,微胶囊副干酪乳杆菌在模拟胃液中3 h存活率达67.52%,模拟肠液中45 min基本得到释放。由于挤压法制备的副干酪乳杆菌微胶囊较高的存活率,操作简便、经济,因此有较为广阔的工业化前景。     

德国苜蓿中植物乳杆菌包埋工艺及特性研究

利用Box-Behnken试验设计,得到最佳包埋工艺条件:菌胶比为1︰6、海藻酸钠质量浓度为1.9%、乳化时间为16 min,CaCl_2质量浓度为0.1 mol/L,包埋产率Y为63.27%,与预测值相差0.67%;模拟体外胃液耐受性,胶囊化外源植物乳杆菌存活率达到46.3%,人工肠液45 min后的释放率达到87.1%,在1%高胆盐环境下微胶囊1 h后的存活率为40.5%;根据Arrhenius方程预测微胶囊有效成分减少2个数量级,有效期为72 d。     

海藻酸钠-魔芋葡甘聚糖微胶囊对嗜酸乳杆菌CGMCC1.2686保护研究

研究了海藻酸钠(ALG)-魔芋葡甘聚糖(KGM)微胶囊对嗜酸乳杆菌CGMCC1.2686的保护效果,特别是KGM分子量对微胶囊保护乳酸菌效果的影响。利用酶法制备不同分子量KGM,将不同分子量KGM与ALG复配,采用内源乳化法制备乳酸菌微胶囊,测定微胶囊物理特性和乳酸菌保护效果各指标。结果发现,ALG与KGM复配,增大了微胶囊粒径(由309μm至412~452μm),且微胶囊粒径随KGM分子量的增加而增加;复配微胶囊机械强度、粘弹性、乳酸菌包埋率、模拟胃液菌体存活率及胆盐菌体存活率均大于ALG微胶囊,其中中等分子量KGM-ALG微胶囊在上述五项指标中均表现最优;回归分析表明,模拟胃液菌体存活率和胆盐菌体存活率与ALG-KGM微胶囊机械强度正相关。因而,ALG与KGM复配提高了微胶囊对乳酸菌的保护效果,同时该保护效果与KGM分子量大小相关。     

4种复合壁材对干酪乳杆菌包埋效果的影响

研究4种复合壁材通过内源乳化法对干酪乳杆菌的包埋效果,及微胶囊化的干酪乳杆菌在模拟胃肠液中的存活情况。结果表明,当海藻酸钠质量分数为2%,海藻酸钠与乳清蛋白含量比11,油水体积比31,海藻酸钠与碳酸钙含量比31时,微胶囊的包埋率最高,为87.50%,且微胶囊形态成球形;以明胶与海藻酸钠做复合壁材时,微胶囊粒度最小,为89.88μm;在模拟胃液中处理2h时,以大豆分离蛋白为复合壁材制得的微胶囊干酪乳杆菌存活率最高,为90.39%;以酪蛋白为复合壁材制得的微胶囊在模拟肠液中肠溶性最好,菌体在30min时基本得到释放。由于蛋白质复合壁材制得的微胶囊安全可食用,包埋效果好,因此可广泛应用于食品加工中。     

微胶囊法提高益生菌抗逆性的研究

以嗜酸乳杆菌为研究对象,以明胶和阿拉伯胶为璧材,采用复凝聚法进行微胶囊化,并对其进行耐酸性、肠溶性和贮藏稳定性试验;以包埋率为考察指标,采用响应面分析法对菌胶质量比、搅拌速度和乳化时间进行分析和优化。结果表明:制备嗜酸乳杆菌微胶囊的最佳工艺条件为菌胶质量比1∶7,乳化搅拌速度611 r/min,反应时间15 min,p H 4.0;制得的微胶囊包埋率为93.5%,与模型预测值相对误差仅为0.46%;嗜酸乳杆菌微胶囊在人工胃液中仍有75%的存活率,在人工肠液中30 min内即可崩解完成。在-4℃和30℃下贮藏30 d后,存活率分别为82%和80%。     

海藻酸钠微胶囊对乳酸菌产乙醛脱氢酶在体外胃肠消化环境中保护作用

利用海藻酸钠及脱脂奶粉等材料,采用氯化钙挤压法包埋产乙醛脱氢酶的植物乳杆菌Lactobacillus plantarum FCJX 102和嗜酸乳杆菌Lactobacillus acidophilus FCJX 104,并探讨其在体外模拟胃肠液中对乙醛脱氢酶的保护作用。研究结果表明,双乳杆菌海藻酸钠微胶囊平均粒径为1. 14 mm,外表圆润饱满,且包埋率达99. 8%。在体外模拟的胃液环境中,消化90 min微胶囊包埋菌体乙醛脱氢酶活性能保留在95%以上,至消化180 min后乙醛脱氢酶活保留率仍然达73. 4%;而未经包埋的双乳杆菌,其乙醛脱氢酶在30 min时就已完全失去活性;在人工肠液中,双乳杆菌海藻酸钠微胶囊颗粒具有较好的肠溶性,菌体乙醛脱氢酶保留率在消化30、50min仍达97. 8%和86. 5%。     

微胶囊化干酪乳杆菌和嗜酸乳杆菌在冻干香蕉粉中的活力研究

为了提高干酪乳杆菌和嗜酸乳杆菌在冻干食品中的活力及其贮藏稳定性,以乳清分离蛋白(WPI)-低聚果糖(FOS)复合物为壁材,通过乳化法制作益生菌微胶囊,以香蕉作为微胶囊载体,将微胶囊混入香蕉泥中冻干成粉。测定微胶囊的包埋率,对包埋益生菌香蕉粉的理化性质,在模拟胃肠道中的活性及贮藏稳定性进行评价。结果表明:WPI-FOS壁材包埋嗜酸乳杆菌和干酪乳杆菌包埋率分别为98%和95%,与WPI壁材相比分别提高8.89%和10.47%(P0.05)。WPI-FOS包埋嗜酸乳杆菌和干酪乳杆菌微胶囊益生菌香蕉粉较未包埋的益生菌香蕉粉缓冲能力分别提高28.83%和73.75%(P0.05),总水溶性糖含量分别提高28.28%和80.95%(P0.05)。经模拟胃肠液处理90 min,WPI-FOS包埋益生菌的香蕉粉中活菌数达到(7.05±0.1)lg cfu/g,而未经WPI-FOS包埋益生菌的香蕉粉在模拟肠液中无菌存活。WPI-FOS包埋益生菌的香蕉粉经4℃、30 d贮藏后活菌数≥8.57 lg cfu/g。以上结果表明:经WPI-FOS壁材包埋益生菌的冻干香蕉粉在不利条件及长时间贮存时,可保持较高的菌活力和较好的贮藏稳定性。     

四种水凝胶壁材对植物乳杆菌包埋微胶囊晶球特性的影响

为提高植物乳杆菌的肠胃液耐受以及释放性能,并筛选适宜制备微胶囊晶球的壁材,本研究采用内源乳化法制备植物乳杆菌微胶囊并通过挤压法制备微胶囊晶球,通过测定包埋率、经胃液消化后存活率以及模拟肠液中对菌体的溶出效果等来评估海藻酸钠、黄原胶、结冷胶、果胶四种壁材对植物乳杆菌微胶囊性能的影响。结果表明：以海藻酸钠为壁材制备微胶囊晶球效果最好,晶球粒径为3.30 mm,水分含量为93.99%,结构紧致、微观形态良好;对植物乳杆菌的包埋率达87.14%,28 d后保留率为56.98%,仍保持在较高水平;体外模拟消化结果显示,植物乳杆菌经胃液消化后存活率高达71.49%,经肠道消化后释放量为2.51×109 CFU/g,表现出以海藻酸钠为壁材制备的微胶囊晶球良好的保护能力和缓释能力。     

内源乳化法制备青春双歧杆菌微胶囊

为提高青春双歧杆菌存活率及抵抗不利环境的能力,以青春双歧杆菌为研究对象,采用海藻酸钠与乳清蛋白为复合壁材,通过内源乳化法制备微胶囊,并对其进行模拟人工胃肠试验和贮藏稳定性试验。以包埋率为考察指标,根据单因素试验探究海藻酸钠添加量、水相油相体积比、吐温80添加量、搅拌速度和乳化时间等因素对包埋率的影响。采用响应面分析法对海藻酸钠添加量、吐温80添加量、搅拌速度进行分析和优化。结果表明: 制备青春双歧杆菌微胶囊的最佳工艺条件为海藻酸钠添加量2%（m/m）,吐温80添加量0.6 mL,搅拌速度430 r/min,包埋率为83.05%。青春双歧杆菌微胶囊于模拟人工胃、肠液中放置180 min,菌体存活率分别为59.89%、66.45%;于4 ℃环境下贮藏42 d,存活率为56.83%。研究表明：以内源乳化法制得的青春双歧杆菌微胶囊对模拟胃肠液环境具有良好的耐酸性及肠溶性,在4 ℃环境中具有良好的贮藏稳定性。     

沙棘益生菌微胶囊的制备及性能研究

目的 制备沙棘益生菌微胶囊, 并进行耐酸性和肠溶性研究。方法 以海藻酸钠、乳清分离蛋白和氯化钙的混合物为壁材, 采用微胶囊技术将沙棘益生菌发酵液进行包埋, 制备得到沙棘益生菌微胶囊。 结果 选取半乳糖增殖培养基作为益生菌的活化培养基, 半乳糖浓度为2%时,对益生菌的增殖效果最佳,不仅缩短了益生菌的延滞期, 而且提高益生菌的生长速率;经过150 min的模拟胃液处理后, 仍然具有较高的存活率, 存活率为61%;在模拟肠液处理中处理60 min之后, 益生菌就会被连续的释放出来。结论 沙棘益生菌微胶囊在胃液中具有良好耐酸性, 在肠液中具有良好的肠溶性。     

海藻酸钠和乳清蛋白作为益生菌包埋壁材的比较

利用海藻酸钠和乳清蛋白分别制备包埋有两歧双歧杆菌的微胶囊,测定了不同微胶囊的粒径、包埋效率、缓冲能力和外观形态,同时还考察了不同微胶囊对两歧双歧杆菌保护效果的影响。结果表明：乳清蛋白微胶囊的粒径和包埋效率均要高于海藻酸钠微胶囊,分别为202.5 μm,87.8%和118.3 μm,48.1%;虽然在高胆盐环境中两种微胶囊对两歧双歧杆菌的保护效果没有显著差别,但在低酸环境、模拟胃液和常温贮藏期中,相比于海藻酸钠微胶囊,乳清蛋白微胶囊将两歧双歧杆菌的存活量分别提高了大约5、2、0.5（lg（CFU/mL））。乳清蛋白微胶囊在pH值偏中性的环境中具有较高的缓冲能力;在外观形态上,由高浓度乳清蛋白溶液制备而来的微胶囊具有较好的呈球性和致密度,这些可能是乳清蛋白微胶囊具有较高保护效果的原因。     

Microencapsulation of Bifidobacterium bifidum F‐35 in Whey Protein‐Based Microcapsules by Transglutaminase‐Induced Gelation

Abstract: Bifidobacterium bifidum F‐35 was microencapsulated into whey protein microcapsules (WPMs) by a transglutaminase (TGase)‐induced method after optimization of gelation conditions. The performance of these WPMs was compared with that produced by a spray drying method (WPMs‐A). WPMs produced by the TGase‐induced gelation method (WPMs‐B) had larger and denser structures in morphological examinations. Native gel and SDS‐PAGE analyses showed that most of the polymerization observed in WPMs‐B was due to stable covalent crosslinks catalyzed by TGase. The degradation properties of these WPMs were investigated in simulated gastric juice (SGJ) with or without pepsin. In the presence of pepsin, WPMs‐A degraded more quickly than did WPMs‐B. Finally, survival rates of the microencapsulated cells in both WPMs were significantly better than that of free cells and varied with the microencapsulation method. However, WPMs‐B produced by TGase‐induced gelation could provide better protection for microencapsulated cells in low pH conditions and during 1 mo of storage at 4 °C or at ambient temperature.     

Volatile Retention and Morphological Properties of Microencapsulated Tributyrin Varied by Wall Material and Drying Method

Butyric acid is an important short‐chain fatty acid for intestinal health and has been shown to improve certain intestinal disease states. A triglyceride containing 3 butyric acid esters, tributyrin (TB) can serve as a source of butyric acid; however, the need to target intestinal delivery and mitigate unpleasant sensory qualities has limited its use in food. Microencapsulation, the entrapment of one or more cores within a matrix, may provide a solution to the aforementioned challenge. This research primarily focused on the influence of (1) wall material: whey and soy protein isolate (WPI and SPI, respectively) and gamma‐cyclodextrin (GCD), (2) wall additives: inulin of varying chain length, and (3) processing method: spray or oven drying (SD or OD, respectively) on the morphological properties and volatile retention of TB within microcapsules. SPI‐based microcapsules retained significantly less (P < 0.001) TB compared to WPI‐based microcapsules as measured by gas chromatography. The inclusion of inulin in the SD WPI‐based microcapsules increased (P < 0.001) TB retention over WPI‐based microcapsules without inulin. Inulin inclusion into WPI‐based microcapsules resulted in a smoother, minimally‐dented, circular morphology as compared to noninulin containing WPI‐based microcapsules as shown by scanning electron microscopy. GCD and TB OD microcapsules retained more (P < 0.001) TB (94.5% ± 1.10%) than all other WPI, WPI‐inulin, and GCD TB SD microcapsules. When spray dried, the GCD‐based microcapsules exhibited (P < 0.001) TB retention than all other microcapsules, indicating the GCD may be unsuitable for spray drying. These findings demonstrate that microencapsulated TB in GCD can lead to minimal TB losses during processing that could be utilized in functional food applications for intestinal health.     

两歧双歧杆菌微胶囊化及其性质研究

以明胶、果胶、海藻酸钠、氯化钙和壳聚糖为壁材,采用乳化法双层包埋制备双歧杆菌微胶囊。制备的微胶囊粒径在10～30μm。检测结果表明,微胶囊内活菌数可达到109 CFU/g以上,菌体包埋率可达到82.24%。经模拟胃酸、胆汁酸处理后活菌数仍在108 CFU/g以上,对酸有很高的耐受力;经人工肠液处理15min,微胶囊几乎全部崩解,肠溶释放率可达到95.81%。通过经典的加速实验证明微胶囊的活菌贮藏稳定性较好,室温下贮藏1年其活菌数仍可以保持在108CFU/g以上。     

Temperature-Sensitive Microcapsules Containing Lactoferrin and Their Action Against Carnobacterium viridans on Bologna

ABSTRACT:  Lactoferrin (LF) was encapsulated in 2 types of emulsion to protect it from contact with agents like divalent cations, which interfere with its antimicrobial activity. First, paste-like microcapsules were prepared as water-in-oil (W₁/O) emulsions from mixtures of 20% w/v LF in distilled water, 20% w/v LF in 3% w/v sodium lactate or in 20 mM sodium bicarbonate, which were emulsified with an oil mixture of 22% butter fat plus 78% corn oil and 0.1% polyglycerol polyricinoleate. Second, freeze-dried double emulsion (W₁/O/W₂), powdered microcapsules were produced following emulsification of paste-like microcapsules in an external aqueous phase (W₂) consisting of a denatured whey protein isolate (WPI) solution. The release of LF from the W₁/O microcapsules was dependent on temperature and NaCl concentration. LF was not released from the W₁/O emulsion at <5.5 °C. Its release was greater from W₁/O microcapsules when suspended in 5% aqueous NaCl than in water at ≥10 °C, whereas LF release from freeze-dried microcapsules was not controlled by temperature change. Paste-like microcapsules were incorporated in edible WPI packaging film to test the antimicrobial activity of LF against a meat spoilage organism Carnobacterium viridans . The film was applied to the surface of bologna after its inoculation with the organism and stored under vacuum at 4 or 10 °C for 28 d. The growth of C. viridans was delayed at both temperatures and microencapsulated LF had greater antimicrobial activity than when unencapsulated. The temperature-sensitive property of the W₁/O microcapsules was reduced when they were incorporated into a WPI film.     

Spray-drying microencapsulation using whey protein isolate and nano-crystalline starch for enhancing the survivability and stability of Lactobacillus reuteri TF-7

Decrease of survivability and stability is a major problem affecting probiotic functional food. Thus, in this study, Lactobacillus reuteri TF-7 producing bile salt hydrolase was microencapsulated in whey protein isolate (WPI) or whey protein isolate combined with nano-crystalline starch (WPI-NCS) using the spray-drying technique to enhance the survivability and stability of probiotics under various adverse conditions. Spherical microcapsules were generated with this microencapsulation technique. In addition, the survival of L. reuteri TF-7 loaded in WPI-NCS microcapsules was significantly higher than WPI microcapsules and free cells after exposure to heat, pH, and simulated gastrointestinal conditions. During long-term storage at 4, 25, and 35 °C, WPI-NCS microcapsules could retain both survival and biological activity. These findings suggest that microcapsules fabricated from WPI-NCS provide the most robust efficiency for enhancing the survivability and stability of probiotics, in which their great potentials appropriate to develop as the cholesterol-lowering probiotic supplements.     

Complex Coacervation as a Novel Microencapsulation Technique to Improve Viability of Probiotics Under Different Stresses

A physicochemical approach has been undertaken to develop polymeric microcapsules for delivering probiotic bacteria with improved viability in functional food products. Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3 %?w/v) and gum arabic (GA, 3 %?w/v) solutions mixed at 2:1 weight ratio. The viability of the bacterial cells during processing (heat treatment and high salt concentrations), under simulated gut conditions (low pH and high bile concentrations) and upon storage, was evaluated. Entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73 %; log scale), especially in comparison with non-encapsulated (free) cells (<19 %). Moreover, after 60 days of refrigerated storage at pH 4.0, the viability of microencapsulated cells was more than 86 %, implying improved protection in comparison with the free cells (<59 %). Complex coacervation with WPI/GA has the potential to deliver live probiotics in low pH foods or fermented products; it is also important to note that the complexes can dissolve at pH 7.0 (gut environment) releasing the microbial cells (desired feature of target delivery systems).     

乳清蛋白在转谷氨酰胺酶作用下包埋益生菌的研究

为了提高双歧杆菌在人体胃肠道中的存活率,以乳清蛋白为壁材,转谷氨酰胺酶为交联剂,通过乳化凝胶的方法制备包埋有两歧双歧杆菌的蛋白质微球。实验表明:以此工艺制备的微球成球性较好,粒径为(308.2±16.2)μm,益生菌包埋率为87.8%±10.0%,与未包埋的两歧双歧杆菌比较,经过包埋后的两歧双歧杆菌在模拟胃液和高胆盐溶液中的存活率分别提高了5个和2个对数值。     

Optimization of Incorporated Prebiotics as Coating Materials for Probiotic Microencapsulation

ABSTRACT: The purpose of this research was to improve probiotic microencapsulation using prebiotics and modern optimization techniques to determine optimal processing conditions, performance, and survival rates. Prebiotics (fructooligosaccharides or isomaltooligosaccharides), growth promoter (peptide), and sodium algi-nate were incorporated as coating materials to microencapsulate 4 probiotics ( Lactobacillus acidophilus, Lacto-bacillus casei, Bifidobacterium bifidum , and Bifidobacterium longum ). The proportion of the prebiotics, peptide, and sodium alginate was optimized using response surface methodology (RSM) to 1st construct a surface model, with sequential quadratic programming (SQP) subsequently adopted to optimize the model and evaluate the survival of microencapsulated probiotics under simulated gastric fluid test. Optimization results indicated that 1% sodium alginate mixed with 1% peptide and 3% fructooligosaccharides as coating materials would produce the highest survival in terms of probiotic count. The verification experiment yielded a result close to the predicted values, with no significant difference ( P > 0.05). The storage results also demonstrated that addition of prebiotics in the walls of probiotic microcapsules provided improved protection for the active organisms. These probiotic counts remained at 10⁶ to 10⁷ colony-forming units (CFU)/g for microcapsules stored for 1 mo and then treated in simulated gastric fluid test and bile salt test.     

Insect‐Resistant Food Packaging Film Development Using Cinnamon Oil and Microencapsulation Technologies

Insect‐resistant films containing a microencapsulated insect‐repelling agent were developed to protect food products from the Indian meal moth (Plodia interpunctella). Cinnamon oil (CO), an insect repelling agent, was encapsulated with gum arabic, whey protein isolate (WPI)/maltodextrin (MD), or poly(vinyl alcohol) (PVA). A low‐density polyethylene (LDPE) film was coated with an ink or a polypropylene (PP) solution that incorporated the microcapsules. The encapsulation efficiency values obtained with gum arabic, WPI/MD, and PVA were 90.4%, 94.6%, and 80.7%, respectively. The films containing a microcapsule emulsion of PVA and CO or incorporating a microcapsule powder of WPI/MD and CO were the most effective (P < 0.05) at repelling moth larvae. The release rate of cinnamaldehyde, an active repellent of cinnamaldehyde, in the PP was 23 times lower when cinnamaldehyde was microencapsulated. Coating with the microcapsules did not alter the tensile properties of the films. The invasion of larvae into cookies was prevented by the insect‐repellent films, demonstrating potential for the films in insect‐resistant packaging for food products. Practical Application : The insect‐repelling effect of cinnamon oil incorporated into LDPE films was more effective with microencapsulation. The system developed in this research with LDPE film may also be extended to other food‐packaging films where the same coating platform can be used. This platform is interchangeable and easy to use for the delivery of insect‐repelling agents. The films can protect a wide variety of food products from invasion by the Indian meal moth.