Encapsulation of probiotic living cells: From laboratory scale to industrial applications

In the recent past, there has been a rising interest in producing functional foods containing encapsulated probiotic bacteria. According to their perceived health benefits, probiotics have been incorporated into a range of dairy products but the major current challenge is to market new probiotic foods. In the research sector, many studies have been reported using dairy products like cheese, yogurt and ice cream as food carrier, and non-dairy products like meat, fruits, cereals, chocolate, etc. However, in the commercial sector only few products containing encapsulated probiotic cells can be found. Nutraceuticals are another important vector for probiotics already developed by several companies in a capsule or a tablet form. The review compiles the technologies used to encapsulate the cells in order to keep them alive and the food matrices used in the research and commercial sector for delivery to the consumer.     

Functional foods as carriers for SYNBIO®, a probiotic bacteria combination

The popularity of functional foods continues to increase as consumers desire flavorful foods that will fulfil their health needs. Among these foods, probiotics may exert positive effects on the composition of gut microbiota and overall health. However, in order to be beneficial, the bacterial cultures have to remain live and active at the time of consumption. The aim of this study was to develop new probiotic food products, such as seasoned cheeses, salami, chocolate and ice-cream with a final probiotic concentration of approximately 10?CFU/daily dose of Lactobacillus rhamnosus IMC 501? and Lactobacillus paracasei IMC 502? mixed 1:1 (SYNBIO?). The survival and viability of probiotics were determined during the foods shelf-life. The values of viable probiotic bacteria of all dairy and non-dairy foods were between 10? and 10?CFU/g of food at the end of the shelf-life and for some of them the values were maintained even after the expiry date. Based on the results of the current study, all the dairy ("Caciotta" cheese, "Pecorino" cheese, "Büscion" Swiss cheese and "Fiordilatte" ice-cream) and non-dairy ("Ciauscolo" salami, Larded salami, Swiss small salami, milk chocolate, dark chocolate, organic jam and chocolate mousse) food products studied would be excellent vehicles to deliver the probiotic health effects because of the high viability of probiotics during the shelf-life of foods and in some cases even after their expiry date.     

Non-dairy probiotic products

There is evidence documenting the beneficial health effects of probiotic microorganisms. Also, many studies have reported that the best matrices to deliver probiotic are dairy fermented products. However, recently several raw materials have been extensively investigated to determine if they are suitable substrates to produce novel non-dairy probiotic microorganisms, and it has been found that traditional fermented foods may contain viable probiotic microorganisms. Numerous such examples can be found in the text. Therefore, the aim of this review was to investigate the utilization of probiotics in new and traditional non-dairy products with probiotic potential. It was found that while cereals have been extensively investigated to develop new probiotic foods; further research about the probiotic beneficial effects of traditional fermented products is needed.     

Review Article: Technological Aspects of Prebiotics in Probiotic Fermented Milks

Prebiotics are food components that exert beneficial effects on health of the host, associated with modulation of the intestinal flora via stimulating the growth and/or activity of the probiotics. One of the recommended ways to maintain high viable numbers of probiotic bacteria in the intestine as well as in the probiotic fermented milk products until the time of consumption is via the use of prebiotics. These compounds can also affect sensory profile, physicochemical and rheological characteristics, and economic properties of probiotic fermented milk products. In this article, technological aspects of prebiotics (viability of probiotics in the product as well as the physicochemical, rheological, sensory, and economic characteristics of product) in probiotic fermented milks are reviewed.     

Probiotication of foods: A focus on microencapsulation tool

BackgroundWith almost thirty years of application in field of probiotics, microencapsulation is becoming an important technology for sustaining cell viability during food production, storage and consumption as well as for the development of new probiotic food carriers. Potentiality of microcapsules in protecting probiotics along human digestive tract seems to be well established. Instead, the inclusion of probiotics into foods, also in microencapsulated form, poses still many challenges for the retention of their viability, being food intrinsic and extrinsic factors crucial for this item.Scope and approachWe collect the relevant literature concerning the use of microencapsulation for the inclusion of probiotics in traditional food vehicles such as milk derivatives and in novel food carriers that were grouped in bakery, meat, fruit and vegetable. Furthermore we intent to highlight within different food categories the main factors that act in challenging probiotics viability and functionality. What we aim is to establish how microencapsulation is effectively promising in the research and development of innovative probiotic foods.Key findings and conclusionsDespite the relevant improvements toward the broadening of probiotic food products and categories, additional efforts have to be attempted. For this purpose, development of easy to use, stable and cheap probiotic microcapsules could be an important key for industrial spreading of microcapsules. Also the monitoring of cell stability along the entire food production including a real storage period as well as the assessment of encapsulated probiotic metabolism are some topics that require additional investigations.     

Probiotics in Goat Milk Products: Delivery Capacity and Ability to Improve Sensory Attributes

Dairy foods, particularly those of bovine origin, are the predominant vehicles for delivery of probiotic bacteria. Caprine (goat) milk also possesses potential for successful delivery of probiotics, and despite its less appealing flavor in some products, the use of goat milk as a probiotic carrier has rapidly increased over the last decade. This review reports on the diversity, applicability, and potential of using probiotics to enhance the sensory properties of goat milk and goat milk‐based products. A brief conceptual introduction to probiotic microorganisms is followed by an account of the unique physicochemical, nutritive, and beneficial aspects of goat milk, emphasizing its advantages as a probiotic carrier. The sensory properties of probiotic‐enriched goat milk products are also discussed. The maintenance of probiotic viability and desirable physicochemical characteristics in goat milk products over shelf life is possible. However, the unpleasant sensory features of some goat milk products remain a major disadvantage that hinder its wider utilization. Nevertheless, certain measures such as fortification with selected probiotic strains, inclusion of fruit pulps and popular flavor compounds, and production of commonly consumed tailor‐made goat milk‐based products have potential to overcome this limitation. In particular, certain probiotic bacteria release volatile compounds as a result of their metabolism, which are known to play a major role in the aroma profile and sensory aspects of the final products.     

Non-dairy Based Probiotics: A Healthy Treat for Intestine

Dairy-based fermented products and yoghurts have been utilized as potential probiotic products since ancient times. However, recent upsurge in interest of consumers towards dairy alternatives has opened up new vistas for non-dairy probiotic research and development. Various matrices and substrates such as cereals, fruit juices, or mixture thereof are being utilized for delivering these beneficial microorganisms. Each matrix offers some advantages over the other. Vast knowledge available on a number of conventional fermented foods can also be utilized for future research in this area. The present review provides an insight on the recent research/developments in the field of non-dairy probiotic foods with particular reference to the foods consumed conventionally, in addition to their commercial availability and a way forward.     

Importance of food in probiotic efficacy

Foods are carriers for the delivery of probiotics to the human body. In addition, foods help to buffer the probiotic through the gastrointestinal tract, regulate their colonization and contain other functional ingredients, such as bioactive components, which may interact with probiotics to alter their functionality and efficacy. The growth and survival of probiotics during gastric transit is affected by the physico-chemical properties of food carriers. Gastric acid, juices and bile tolerance, adherence to gastrointestinal epithelium and the acid production of probiotics are also affected by the food ingredients used in probiotic delivery. Same probiotic strains could vary in functional and technological properties in the presence of different food ingredients. Prebiotic food ingredients encourage the growth of probiotic bacteria. The appropriate combination of prebiotics and probiotics manifest higher potential for a synergistic effect. Originally, probiotic delivery was consistently associated with foods, particularly dairy foods. But nowadays, there is an increasing trend toward using probiotics in different food systems despite its original sources and even as nutraceuticals, such as in capsules. This changing trend in delivering probiotics may lead to a reduction in functional efficacy due to the exclusion of the potential synergistic effect of the food. Thus, selection of suitable food systems to deliver probiotics is a vital factor that should be considered in developing functional probiotic foods. This review focuses on information related to the effect of processed food products on functional efficacy of probiotics.     

Nonbovine milk and its products as sources of probiotics delivery: An overview of its viability,functionality and product quality characteristics

Dairy products are the most predominant food carriers for probiotics, providing adequate therapeutic and functional benefits to the host when sufficient probiotics are maintained. Bovine milk currently dominates the global probiotic food market, but there is an increasing trend of applying nonbovine milk from other dairy animals as probiotic carrier food matrices as described in this review. Nonbovine dairy products can be considered suitable food matrices for probiotic delivery due to their excellent probiotic viability (mostly >log 7 cfu/mL or g) during shelf life, functional properties and product quality characteristics, being considered desirable and novel dairy products.     

Challenges in the addition of probiotic cultures to foods

Probiotic cultures are increasingly being added to foods in order to develop products with health-promoting properties. Although the literature is abundant on the beneficial effects of bifidobacteria and Lactobacillus acidophilus on health, little information is available on the challenges industry faces in adding these probiotic cultures to food products. The aim of this article is to examine seven issues that should be addressed when developing functional foods: 1) type or form of probiotic that should be used; 2) addition level required to have a beneficial effect; 3) toxicity; 4) effect of the processing steps on viability; 5) determination, in the product, of the cell populations added; 6) stability during storage; 7) changes in sensory properties of the foods.     

Supplementation of Spirulina platensis and Chlorella vulgaris Algae into Probiotic Fermented Milks

Viability of probiotic bacteria during the production and storage of fermented milks is the most important topic of discussion in the dairy industry. Addition of microalgae into milk for the production of fermented milk in order to enhance the viability of probiotics has been the subject of recent research. Spirulina and Chlorella are the most widely noted microalgae for fermented milks. They affect not only the viability of probiotics in final product but also the sensory attributes of them. Incorporation of microalgae into probiotic fermented milks along with enhancing the viability of probiotics would increase their functional characteristic. This is because they contain a wide range of nutrients and nutraceuticals and are considered as “functional food.” This article reviews the effects of supplementation of Spirulina platensis and Chlorella vulgaris into probiotic fermented milks on their different quality characteristics.     

Microencapsulation of bacteria: A review of different technologies and their impact on the probiotic effects

Probiotic based products are associated with many health benefits. However, the main problem is the low survival of these microorganisms in food products and in gastrointestinal tract. Providing probiotics with a physical barrier is an efficient approach to protect microorganisms and to deliver them into the gut. In our opinion, microencapsulation is one of the most efficient methods, and has been under especial consideration and investigation. However, there are still many challenges to overcome with respect to the microencapsulation process. This review focuses mainly on the methodological approach of probiotic encapsulation including materials and results obtained using encapsulated probiotic in food matrices and different pathologies in animal models.Industrial relevanceThe inclusion of probiotics into food matrices is one of the most challenging lines of research in food technology. Probiotics in general, and some strains in particular, have a low resistance to different environmental conditions, such as oxygen, light or temperature. Thus, the protection and isolation of the microorganism from the food matrix and the environmental condition are crucial for the development of new probiotic food. In this sense, microencapsulation has gained an increasing interest, since it has been demonstrated that it could protect the bacteria not only during its production process but also during its incorporation into the food matrix, also with protective effects during storage. In conclusion, microencapsulation is of great interest since it could allow a wider application of probiotics in the food market, actually restricted to fresh or powder products.     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

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.     

Review on potential non-dairy synbiotic beverages: a preliminary approach using legumes

In the past few years, certain functional foods have gained consumer acceptance like those containing synbiotics (a blend of both prebiotics and probiotics) in different food systems. Synbiotics enhance gut functionality and confer health benefits to humans. However, due to the limitations exerted by dairy-based matrices like lactose intolerance, milk allergies, limited shelf life and inclination towards veganism, consumer’s interest in non-dairy foods has increased. Among the non-dairy matrices, legumes (such as chickpeas, kidney beans, lupin) are the less explored areas with the majority focus on only soya beans. The present review gives brief information about the different research associating with various legume-based probiotics, prebiotics and synbiotic foods narrowing down specifically to beverages. The integration of such information will allow the researchers to explore product development using new prebiotic ingredients that have not been studied in much detail and hold an exceptional potential to be employed in the synbiotic food industry.     

Bacterial survival and adhesion for formulating new oral probiotic foods

Abstract

Probiotics are defined as live microorganisms, which, when administered in adequate amounts, confer health benefits to the host. Traditionally, probiotic food research has heavily focused on the genera Bifidobacteria and Lactobacilli, along with their benefits for gut health. Recently with the identification of new probiotic strains specifically intended for oral health applications, the development of probiotic foods for oral health benefits has garnered interest, with a renewed focus on identifying new food formats for delivering probiotics. The development of novel oral probiotic foods is highly complex, as the composition of a food matrix dictates: (1) bacterial viability during production and shelf life and (2) how bacteria partition with components within a food matrix and subsequently adhere to oral cavity surfaces. At present, virtually no information is available on oral probiotic strains such as Streptococcus salivarius; specifically, how orally-derived strains survive under different food parameters. Furthermore, limited information exists on the partition behavior of probiotics with food components, governed by physico-chemical interactions and adhesion phenomena. This review aspires to examine this framework by providing a foundation with existing literature related to the common probiotic genera, in order to inform and drive future attempts of designing new oral probiotic food formats.     

乳酸菌在燕麦基质中生长特性的研究

非乳益生菌食品已成为益生菌食品发展的重要趋势,以燕麦为基质的益生菌食品具有高膳食纤维、低脂肪和无乳糖不耐症等优点。文中研究了乳酸菌在燕麦基质中生长的可行性,并以瑞士乳杆菌(Lactobacillushelveticus)为研究对象,考察了基质的预处理和基质浓度等对乳酸菌生长的影响。研究结果表明,不同的乳酸菌在燕麦基质中的生长能力具有较大差别。利用富含多种营养物和酶的麦芽对燕麦成分进行适当的水解可以促进瑞士乳杆菌的生长。向燕麦糊(燕麦7%,质量分数)中添加1%(质量分数)的麦芽,在60℃水解30 min后,以燕麦为基质,37℃发酵4 h,瑞士乳杆菌生长可达到稳定期,菌体浓度可提高2个数量级,达到108 CFU/mL。发酵后的燕麦糊在4℃下保藏21 d后,活菌数可保持107 CFU/mL。     

Performance in Nondairy Drinks of Probiotic L. casei Strains Usually Employed in Dairy Products

The increase in vegetarianism as dietary habit and the increased allergy episodes against dairy proteins fuel the demand for probiotics in nondairy products. Lactose intolerance and the cholesterol content of dairy products can also be considered two additional reasons why some consumers are looking for probiotics in other foods. We aimed at determining cell viability in nondairy drinks and resistance to simulated gastric digestion of commercial probiotic lactobacilli commonly used in dairy products. Lactobacillus casei LC‐01 and L. casei BGP 93 were added to different commercial nondairy drinks and viability and resistance to simulated gastric digestion (pH 2.5, 90 min, 37 °C) were monitored along storage (5 and 20 °C). For both strains, at least one nondairy drink was found to offer cell counts around 7 log orders until the end of the storage period. Changes in resistance to simulated gastric digestion were observed as well. Commercial probiotic cultures of L. casei can be added to commercial fruit juices after a carefull selection of the product that warrants cell viability. The resistance to simulated gastric digestion is an easy‐to‐apply in vitro tool that may contribute to product characterization and may help in the choice of the food matrix when no changes in cell viability are observed along storage. Sensorial evaluation is mandatory before marketing since the product type and storage conditions might influence the sensorial properties of the product due to the possibility of growth and lactic acid production by probiotic bacteria.     

Protecting probiotic bacteria by microencapsulation: challenges for industrial applications

The use of probiotic bacteria in novel foods to provide beneficial health effects is today of increasing interest in the food industry. The process stability of probiotics is, however, not always optimal. Microencapsulation technology can be used to maintain the viability of probiotic bacteria during food product processing and storage. Both true microcapsules with coating as well as microspheres where the bacteria are evenly spread in the coating material are discussed. It is important that encapsulation keeps the probiotics active through the gastrointestinal tract and releases them in their target organ. The survival of microencapsulated cells in simulated gastric conditions is therefore also reviewed. Polysaccharides like alginate, gellan, κ-carrageenan and starch are the most commonly used materials in microencapsulation of bifidobacteria and lactobacilli. Techniques commonly applied for probiotic microencapsulation are emulsion, extrusion, spray drying, and adhesion to starch. Bead stability can be improved by using different coating materials, e.g. chitosan. Future challenges in the field include recognition of new potent applications, selection of appropriate techniques, materials and bacterial strains, and minimizing the extra costs incurred by microencapsulation.     

Olive paste as vehicle for delivery of potential probiotic Lactobacillus plantarum 33

Use of probiotic bacteria and consumes in large — in novel foods to provide beneficial health effects has attracted an increasing interest by the food industry and fermented olives are an excellent example of a new generation of those foods from plant origin so as to assure maximum viability by the time of ingestion during processing and storage of food products, as well as during transit through the gastrointestinal tract.Our study focused on production, characterization and assessment of efficacy of microencapsulation upon survival of probiotic strains and sensory properties of the final olive paste throughout refrigerated storage. Microencapsulation appears to be an effective technique for strain survival, depending on the operating temperature and experimental results on tolerance to gastrointestinal-like conditions, and ability to adhere to intestinal epithelium is thereby presented and discussed. The sensory panel rated all experienced matrices as good, including overall acceptance without significant preference between them. However, the success of microencapsulation was more limited when incorporated into olive paste. Free cells of Lactobacillus plantarum 33 proved able to survive in olive paste during storage at refrigerated temperatures.