植物蛋白微胶囊对益生菌包埋的研究进展

益生菌对宿主健康具有一定的益生作用而被广泛应用于食品领域。然而益生菌对外界环境比较敏感,且进入机体后不耐胃液、胆盐等恶劣环境,导致其存活率大大下降。微胶囊技术对益生菌包埋可以解决这一问题,且将植物蛋白作为益生菌的包埋壁材,不仅可以提高益生菌在不良环境中的存活率,还可以作为载体用于益生菌肠道的定位释放。本文综述了大豆蛋白、豌豆蛋白等对益生菌的包埋以及益生菌微胶囊在食品中的应用,为植物蛋白微胶囊技术包埋益生菌提供参考依据。     

益生菌微胶囊化研究现状

微胶囊技术因能显著提高益生菌的存活力和耐受性而备受关注。本文介绍了微胶囊技术在益生菌中的应用现状,对目前使用的益生菌微胶囊包埋方法的优缺点进行比较分析;对常用的微胶囊壁材的性质及其应用现状进行概述;对微胶囊的干燥方法及存在的问题进行探讨。在此基础上对益生菌微胶囊化的应用前景进行展望。     

益生菌微胶囊化壁材与方法的研究进展

益生菌微胶囊技术因其能显著提高益生菌在胃肠道中的存活率而备受关注。本文介绍了益生菌微胶囊技术中所使用的包埋材料及方法,并提出益生菌微胶囊新的研究方向。     

微胶囊制备工艺对益生菌活性的影响

益生菌微胶囊包埋技术因其能显著提高益生菌在加工、贮藏以及人体内胃肠道中的活性而备受关注。介绍了微胶囊不同壁材,包埋方法及干燥方法对益生菌活性的影响,以此为今后的相关研究提供一些参考。     

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。     

微胶囊化对植物乳杆菌在高盐干酪中存活率的影响

为了提高益生菌在高盐干酪中的存活能力,以高盐白卤(white-brined)干酪为例,研究微胶囊化的植物乳杆菌在高盐干酪中的活性变化。通过挤压法制作微胶囊,将其添加至白卤干酪中,观察微胶囊的结构及其在干酪中的分布,并对益生菌在白卤干酪中的存活能力及模拟胃肠道中的活性进行评价。结果表明:微胶囊为球形,表面光滑,其平均直径100~140μm,菌体于微胶囊内部,而微胶囊在干酪中分布均匀;干酪贮存期间,包埋的益生菌数量下降,显著低于未包埋的益生菌(P0.05),分别由(12.30±0.20)lg(cfu/g)降至(9.27±0.06)lg(cfu/g),(11.27±0.12)lg(cfu/g)降至(6.60±0.06)lg(cfu/g)。经模拟胃肠道处理,微胶囊活菌数降至7.47 lg(cfu/g)和7.83 lg(cfu/g),较未包埋分别提高了1.4 lg(cfu/g)(P0.05)和1.03 lg(cfu/g)(P0.05)。质构分析及感官评价表明,含包埋与未包埋植物乳杆菌的干酪组无显著差异(P0.05)。以上结果表明,微胶囊化益生菌菌数较未微胶囊提高了2.6 lg(cfu/g),有效提高了高盐干酪中益生菌的活性。     

益生菌微胶囊包埋及靶向递送体系研究进展

益生菌因具有调节肠道菌群，预防便秘，增强肠道免疫力等功能，在新型功能性食品、医药和微生态制剂研发生产中具有广阔的应用前景。近年来，益生菌产品的消费以20%的速度在逐年增加。由于益生菌在加工和储藏过程中极易受外界光、温度、氧气等影响而失活，摄食后还需经受住胃酸、胆盐等胃肠环境的挑战，只有少数菌能到达肠道，因此目前很多益生菌产品的活菌数和实际效果都难以达到预期。如何长时间保持益生菌的活性成为制约益生菌产业发展的“卡脖子”技术。近年来，微胶囊包埋及靶向递送体系在材料以及益生菌领域的应用方面取得的重大进展，提高了益生菌及其产品在加工、贮藏过程中的存活率、稳定性和实际功效。本文概述益生菌靶向递送研究现状，总结近年来益生菌微胶囊的壁材、包埋技术的研究进展、存在问题和发展趋势，旨在为进一步研究和开发高活性益生菌产品和技术，提高益生菌产品在体内的功效提供参考。     

海洋寡糖益生菌微胶囊的制备和体外评估及其对动物肠道菌群的调节作用

为解决益生菌不耐低pH值、不耐氧的缺点,采用微胶囊包埋技术,以海藻酸钠为壁材用乳化法制备长双歧杆菌藻酸盐微胶囊。将基础藻酸盐微胶囊外包壳寡糖（chitosan oligosaccharides,COS）或在藻酸盐壁材中添加藻酸盐寡糖（alginate oligosaccharides,AOS）分别制备两种海洋寡糖微胶囊：COS-微胶囊和AOS-COS-微胶囊。体外实验表明：两种海洋寡糖微胶囊均可以显著提高长双歧杆菌在模拟消化液处理后或在4 ℃贮藏期内的存活率。AOS-COS-微胶囊在模拟胃液处理后仍能保持106 CFU/g以上的活菌数。在连续的模拟消化液处理后,AOS-COS-微胶囊中的活菌量达到基础微胶囊中的约1 000 倍。两种海洋寡糖微胶囊在4 ℃贮藏28 d后仍均能保持108 CFU/g以上的活菌数。体内实验表明：相比较未包埋的长双歧杆菌或基础微胶囊,海洋寡糖微胶囊可以显著提高动物肠道菌群中益生菌的含量,同时降低条件致病菌的含量,具有最佳的调节肠道菌群效果。因此,海洋寡糖益生菌微胶囊产品将是一种有巨大应用前景的新型功能性益生菌食品。     

复合海藻酸钠益生菌微胶囊研究进展

海藻酸钠微胶囊制备的研究一直是微胶囊技术的重要组成部分。由海藻酸钠制成的益生菌胶囊有孔隙和裂缝,通过利用不同壁材与海藻酸钠组合形成复合海藻酸钠微胶囊,可对益生菌起到更有效的保护作用。本文概述了三类材料对海藻酸钠微胶囊复合的研究进展,包括添加益生元刺激益生菌增长,共混纳米材料来提升机械性能,利用涂层成膜材料减少外部物质进入或内部芯材渗透。总结不同包埋结构的优缺点,并对益生菌微胶囊包埋的发展趋势进行了展望,以期为复合海藻酸钠益生菌微胶囊的科学研究提供参考。     

提高食品中益生菌数量的两大新技术

益生菌是一种对人类健康起着重要作用的微生物,并广泛应用于食品生产,然而,益生菌自身比较脆弱,容易受周围环境的影响而导致食品中益生菌菌数的快速下降,严重影响了益生菌的益生作用,因此,对益生菌进行包埋,提高食品中益生菌的稳定性和存活能力将对我们进一步开发益生菌系列产品至关重要.本文根据目前国内外益生菌包埋技术研究的现状,对目前研究较多的微胶囊包埋技术和双层包埋技术的原理,优缺点以及实际应用情况进行综述。     

酸乳中益生细菌活性影响因素的研究概况

阐述了发酵型酸乳中益生菌的种类，特性和活性条件。重点讨论了益生菌的（特别是酸乳中常用的乳酸细菌）保健功能，探讨了酸乳中益生菌活性抑制因素和提高益生菌活性的方法，目的在于探求和开发生产高质量，高活性益生菌酸乳途径。     

Application of RBGR--a simple way for screening of oxygen tolerance in probiotic bacteria.

Oxygen toxicity is a major problem in the survival of probiotic bacteria in dairy foods. High levels of oxygen in the product are detrimental to the viability of these predominantly anaerobic bacteria. Screening probiotic bacteria for oxygen tolerance before their incorporation could ensure high cell counts in food products during storage. Reported techniques have focused only on qualitative estimations of oxygen tolerance in probiotic bacteria. To characterize the oxygen tolerance of a large number of organisms, a quantitative measurement is essential. For the first time, the oxygen tolerance of several probiotic strains was measured quantitatively using an index known as Relative Bacterial Growth Ratio (RBGR). The tolerance to oxygen varied between organisms, and this technique can therefore be applied for screening probiotic bacteria for oxygen tolerance.     

Acid, bile, and heat tolerance of free and microencapsulated probiotic bacteria

ABSTRACT:  Eight strains of probiotic bacteria, including Lactobacillus rhamnosus , Bifidobacterium longum, L. salivarius, L. plantarum , L. acidophilus , L. paracasei , B. lactis type Bl-O4, and B. lactis type Bi-07, were studied for their acid, bile, and heat tolerance. Microencapsulation in alginate matrix was used to enhance survival of the bacteria in acid and bile as well as a brief exposure to heat. Free probiotic organisms were used as a control. The acid tolerance of probiotic organisms was tested using HCl in MRS broth over a 2-h incubation period. Bile tolerance was tested using 2 types of bile salts, oxgall and taurocholic acid, over an 8-h incubation period. Heat tolerance was tested by exposing the probiotic organisms to 65 °C for up to 1 h. Results indicated microencapsulated probiotic bacteria survived better ( P < 0.05) than free probiotic bacteria in MRS containing HCl. When free probiotic bacteria were exposed to oxgall, viability was reduced by 6.51-log CFU/mL, whereas only 3.36-log CFU/mL was lost in microencapsulated strains. At 30 min of heat treatment, microencapsulated probiotic bacteria survived with an average loss of only 4.17-log CFU/mL, compared to 6.74-log CFU/mL loss with free probiotic bacteria. However, after 1 h of heating both free and microencapsulated probiotic strains showed similar losses in viability. Overall microencapsulation improved the survival of probiotic bacteria when exposed to acidic conditions, bile salts, and mild heat treatment.     

Survival of Microencapsulated Probiotic Bacteria after Processing and during Storage: A Review

The use of live probiotic bacteria as food supplement has become popular. Capability of probiotic bacteria to be kept at room temperature becomes necessary for customer's convenience and manufacturer's cost reduction. Hence, production of dried form of probiotic bacteria is important. Two common drying methods commonly used for microencapsulation are freeze drying and spray drying. In spite of their benefits, both methods have adverse effects on cell membrane integrity and protein structures resulting in decrease in bacterial viability. Microencapsulation of probiotic bacteria has been a promising technology to ensure bacterial stability during the drying process and to preserve their viability during storage without significantly losing their functional properties such acid tolerance, bile tolerance, surface hydrophobicity, and enzyme activities. Storage at room temperatures instead of freezing or low temperature storage is preferable for minimizing costs of handling, transportation, and storage. Concepts of water activity and glass transition become important in terms of determination of bacterial survival during the storage. The effectiveness of microencapsulation is also affected by microcapsule materials. Carbohydrate- and protein-based microencapsulants and their combination are discussed in terms of their protecting effect on probiotic bacteria during dehydration, during exposure to harsh gastrointestinal transit and small intestine transit and during storage.     

A novel eukaryotic cell culture model to study antiviral activity of potential probiotic bacteria

As shown in many intervention studies, probiotic bacteria can have a beneficial effect on rotavirus and HIV-induced diarrhoea. In spite of that fact, antiviral effects of probiotic bacteria have not been systematically studied yet. Non-tumorigenic porcine intestinal epithelial cells (IPEC-J2) and alveolar macrophages (3D4/2) were treated in different experimental designs with probiotic and other lactic bacteria and their metabolic products. Vesicular stomatitis virus (VSV) was used in the study as a model virus. Cell survival and viral inhibition were determined by antiviral assay and confirmed by immunofluorescence. Pre-incubation of cell monolayers with probiotic bacteria reduced viral infectivity up to 60%. All bacteria used prevented VSV binding to the cell monolayers by direct binding of VSV to their surface. Probiotic and other lactic bacteria prevented viral infection also by establishment of the antiviral state in pre-treated cell monolayers. Probiotic and other lactic bacteria secreted antiviral substances during their growth, as the infectivity of the virus was diminished by 68% when bacterial supernatants were tested. It was shown for the first time that probiotic and other lactic bacteria exhibit an antiviral activity in a cell culture model. Possible mechanisms of antiviral activity include: 1) hindering the adsorption and cell internalisation of the VSV due to the direct trapping of the virus by the bacteria, 2) "cross-talk" with the cells in establishing the antiviral protection and 3) production of metabolites with a direct antiviral effect.     

Antimicrobial effects of probiotic bacteria against selected species of yeasts and moulds in cheese-based dips

The antimicrobial properties of selected probiotic bacteria against Aspergillus niger , Penicillium roqueforti , Fusarium spp., Candida albicans and Saccharomyces cerevisiae were examined. Well diffusion and spot and streak methods showed strong inhibition effect of probiotic bacteria and their metabolites against moulds and minimal effect against yeasts. Among the moulds species tested, the inhibitory effect was strongest against Fusarium spp., moderate against Penicillium roqueforti and minimal against A. niger . All strains of Lactobacillus rhamnosus and L. paracasei subsp. paracasei showed maximum inhibitory effect. When probiotic bacteria and yeasts and moulds were co-cultured in broth media, strains of L. rhamnosus showed maximum inhibitory effect, whereas L. paracasei subsp. paracasei , L. acidophilus , Bifidobacterium animalis and Propionibacterium showed moderate inhibitory effect against C. albicans . Saccharomyces cerevisiae was minimally controlled by probiotic bacteria. Pre-grown probiotic bacterial culture metabolites controlled yeasts and moulds more effectively than their freeze-dried or frozen forms. Adding metabolites of probiotic bacteria (5% w/w) showed an effective control against A. niger , Fusarium spp. and C. albicans during the shelf life of 10 weeks at 4 °C and no colonies of yeasts and moulds were formed on the surface of the dip.     

Probiotics,prebiotics, and microencapsulation: A review

The development of a suitable technology for the production of probiotics is a key research for industrial production, which should take into account the viability and the stability of the organisms involved. Microbial criteria, stress tolerance during processing, and storage of the product constitute the basis for the production of probiotics. Generally, the bacteria belonging to the genera Lactobacillus and Bifidobacterium have been used as probiotics. Based on their positive qualities, probiotic bacteria are widely used in the production of food. Interest in the incorporation of the probiotic bacteria into other products apart from dairy products has been increasing and represents a great challenge. The recognition of dose delivery systems for probiotic bacteria has also resulted in research efforts aimed at developing probiotic food outside the dairy sector. Producing probiotic juices has been considered more in the recent years, due to an increased concern in personal health of consumers. This review focuses on probiotics, prebiotics, and the microencapsulation of living cells.     

Interactions among lactic acid starter and probiotic bacteria used for fermented dairy products

Interactions among lactic acid starter and probiotic bacteria were investigated to establish adequate combinations of strains to manufacture probiotic dairy products. For this aim, a total of 48 strains of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactococcus lactis, Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium spp. (eight of each) were used. The detection of bacterial interactions was carried out using the well-diffusion agar assay, and the interactions found were further characterized by growth kinetics. A variety of interactions was demonstrated. Lb. delbrueckii subsp. bulgaricus was found to be able to inhibit S. thermophilus strains. Among probiotic cultures, Lb. acidophilus was the sole species that was inhibited by the others (Lb. casei and Bifidobacterium). In general, probiotic bacteria proved to be more inhibitory towards lactic acid bacteria than vice versa since the latter did not exert any effect on the growth of the former, with some exceptions. The study of interactions by growth kinetics allowed the setting of four different kinds of behaviors between species of lactic acid starter and probiotic bacteria (stimulation, delay, complete inhibition of growth, and no effects among them). The possible interactions among the strains selected to manufacture a probiotic fermented dairy product should be taken into account when choosing the best combination/s to optimize their performance in the process and their survival in the products during cold storage.     

益生乳酸菌在乳制品中的应用研究进展

益生乳酸菌是一类能利用碳水化合物发酵产生大量乳酸,且对宿主有益的微生物。乳制品在人类膳食结构中占有十分重要的地位,随着消费者对乳品品质和健康要求的提升,具有各种健康功能的益生乳酸菌在乳品中的应用及相关加工技术和功能产品的研发日益受到关注。通过添加益生乳酸菌等活性因子获得功能性乳制品,是增强乳品健康功效的有效方法。本文综述了近年来有关益生乳酸菌在发酵乳、干酪、乳饮料、冰淇淋和奶粉等乳制品中的应用研究现状,重点介绍了益生乳酸菌发挥功能的主要代谢产物酶类和胞外多糖的应用研究,包括在不同乳制品中益生乳酸菌及其产物发挥的作用,常用的益生乳酸菌菌株种类,生产加工过程中存在的主要问题及解决方法,为益生乳酸菌在乳制品中的应用开发提供参考。