Effect of storage in a fruit drink on subsequent survival of probiotic lactobacilli to gastro-intestinal stresses

Physiological and biochemical characteristics of the carbon ion beam irradiation-generated mutant strain Clostridium butyricum FZM 240 in vitro and in vivo

Clostridium butyricum (C. butyricum) represents a new generation of probiotics, which is beneficial because of its good tolerance and ability to produce beneficial metabolites, such as short-chain fatty acids and enzymes; however, its low enzyme activity limits its probiotic efficacy. In this study, a mutant strain, C. butyricum FZM 240 was obtained using carbon ion beam irradiation, which exhibited greatly improved enzyme production and tolerance. The highest filter paper, endoglucanase, and amylase activities produced by C. butyricum FZM 240 were 125.69 U/mL, 225.82 U/ mL, and 252.28 U/mL, which were 2.58, 1.95, and 2.21-fold higher, respectively, than those of the original strain. The survival rate of the strain increased by 11.40 % and 5.60 % after incubation at 90 °C for 5 min and with simulated gastric fluid at pH 2.5 for 2 h, respectively, compared with that of the original strain. Whole-genome resequencing and quantitative real-time PCR(qRT-PCR) analysis showed that the expression of genes related to enzyme synthesis (GE000348, GE001963 and GE003123) and tolerance (GE001114) was significantly up-regulated, while that of genes related to acid metabolism (GE003450) was significantly down-regulated. On this basis, homology modeling and functional prediction of the proteins encoded by the mutated genes were performed. According to the results, the properties related to the efficacy of C. butyricum as a probiotic were significantly enhanced by carbon ion beam irradiation, which is a novel strategy for the application of Clostridium spp. as feed additives.

Viability and In Vitro Gastrointestinal Transit Tolerance of Multispecies Probiotic Combinations Incorporated into Orange Juice and Drinking Water

Little is known about how combining probiotics affects the storage survival and functional performance of individual probiotics when incorporated into non-dairy drinks. Viability of Lacticaseibacillus rhamnosus GG (LG), Limosilactobacillus reuteri ATCC 55730 (LR), Bifidobacterium animalis subsp. lactis BB-12 (Bb), and Propionibacterium jensenii 702 (PJ), either alone or in multi-species combinations included in orange juice (OJ), were assessed during storage in refrigerated conditions and compared with bottled water (BW). The tolerance of probiotics included in refrigerated OJ to simulated gastrointestinal conditions was also examined. LG and LR viabilities were significantly higher in OJ than in BW (p ≤ 0.001), while the reverse was evident for PJ. Bb maintained high viability in both drinks. LG-PJ in both drinks and Bb-PJ in BW resulted in greater viabilities among the paired combinations compared to their respective monocultures when incorporated separately (p ≤ 0.001). The viability of LG in the LG-Bb-PJ combination improved significantly in BW compared with LG alone (p ≤ 0.001). OJ did not alter bacterial tolerance to simulated gastric juice but diminished tolerance to simulated intestinal juice (SIJ). In all combinations, tolerance of LG and LR to SIJ was improved, whereas tolerance of PJ declined significantly compared with respective monocultures (p ≤ 0.001). In conclusion, probiotic storage stability and gastrointestinal transit tolerance were species-dependent and affected by carrier type and combinations. These effects should be considered when formulating probiotic products.

Probiotics media: significance, challenges, and future perspective - a mini review

The health benefits associated with probiotics have increased their application in pharmaceutical formulations and functional food development. High production of probiotic biomass requires a cost-effective production method and nutrient media optimization. The biomass production of probiotics can be enhanced by optimizing growth parameters such as substrate, pH, incubation time, etc. For economical industrial production of probiotic biomass, it is required to design a new medium with low cost. Wastes from the food industries are promising components for the development of the low-cost medium. Industrial wastes such as cheese whey and corn steep liquor are excellent examples of reliable sources of nitrogen for the biomass production of probiotic bacteria. The increased yield of biomass reduced the cost of production. This review focuses on the importance of probiotic media for biomass production and its challenges.

Graphical Abstract

Characterization of a fermented coconut milk product with and without strawberry pulp

The development of plant-based milks for use as functional foods is relatively new and challenging. The objective of this work was to develop and characterize two coconut milk products fermented by Lactobacillus reuteri LR 92. The best proportion of gums to promote greater viscosity and absence of syneresis of the beverage was 0.15% xanthan gum (w/v) and 0.05% guar gum (w/v). Two products were formulated: fermented coconut milk (FC) and fermented coconut milk with strawberry pulp (FCS). After gastrointestinal simulation, a high survival rate of L. reuteri was found for the products, with 81.63 ± 0.58% for FC and 74.17 ± 1.65% for FCS. In the hedonic acceptance sensory test (total 9 points), the products obtained global scores above 7.5. In the attitude scale test (total 7 points), 5.10 ± 1.28 for FC and 5.48 ± 1.30 for FCS. Among the fatty acids detected, the products had a higher percentage of lauric acid, with values ranging from 37.89 ± 0.89% to 44.45 ± 3.16%. The FC and FCS products showed promising results, indicating that fermented coconut milk beverages are suitable for the development of new functional products with high acceptability by the consumer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05303-1.

Fostering next-generation probiotics in human gut by targeted dietary modulation: An emerging perspective

Emerging evidence and an in-depth understanding of the microbiome have helped in identifying beneficial commensals and their therapeutic potentials. Specific commensal taxa/ strains of the human gut microbiome have been positively associated with human health and recently termed as next-generation probiotics (NGPs). Of these, Akkermansia muciniphila, Ruminococcus bromii, Faecalibacterium prausnitzii, Anaerobutyricum hallii, and Roseburia intestinalis are the five most relevant gut-derived NGPs that have demonstrated therapeutic potential in managing metabolic diseases. Specific and natural dietary interventions can modulate the abundance and activity of these beneficial bacteria in the gut. Hence, the understanding of targeted stimulation of specific NGP by specific probiotic-targeted diets (PTD) is indispensable for the rational application of their combination. The supplementation of NGP with its specific PTD will help the strain(s) to compete with harmful microbes and acquire its niche. This combination would enhance the effectiveness of NGPs to be used as "live biotherapeutic products" or food nutraceuticals. Under the current milieu, we review various PTDs that influence the abundance of specific potential NGPs, and contemplates potential interactions between diet, microbes, and their effects on host health. Taking into account the study mentioned, we propose that combining NGPs will provide an alternate solution for developing the new diet in conjunction with PTD.

Survival of Lactobacillus paracasei subsp. paracasei LBC 81 in Fermented Beverage from Chickpeas and Coconut in a Static In Vitro Digestion Model

The objective of this study was to evaluate in a static in vitro digestion model the survival of Lactobacillus paracasei subsp. paracasei LBC 81 in fermented chickpea and coconut beverage. The fermented beverage was stored for 1 and 8 days at 4 °C and then submitted to gastric juice, pancreatic juice, or sequential exposure to gastric and pancreatic juice. The experiment controls were (i) control 1—suspension of cells in 0.85% saline solution; (ii) control 2—cell suspension in chickpea and coconut beverage. The survival of L. paracasei was determined in log CFU/mL and expressed as a survival percentage. The survival of L. paracasei in the fermented beverage after exposure to gastric juice and sequential exposure to gastric and pancreatic juice was 99.47 + 2.05% and 93.21 + 0.43%, respectively. These values were higher than those found for controls 1 and 2. The storage condition of the fermented beverage for 1 or 8 days at 4 °C did not affect the survival after exposure to gastric juice, pancreatic juice, or sequential exposure. The results obtained in this study conclude that the fermented beverage of chickpeas and coconut is an excellent carrier for L. paracasei LBC 81, capable of enhancing survival to gastrointestinal conditions and ensuring a greater number of viable cells reaching the intestinal epithelium.

Coating Lacticaseibacillus rhamnosus GG in Alginate Systems: an Emerging Strategy Towards Improved Viability in Orange Juice

Fruit juices are successfully proposed as suitable probiotic vehicles, but researchers' efforts should be developed to avoid effects of bacteria overgrowing on sensory and nutritional cues of final products and to preserve viability of probiotic bacteria during storage. In the present study, encapsulation of Lacticaseibacillus rhamnosus GG strain in alginate systems was performed through ionotropic gelation technology. The alginate systems were optimized by using Box-Behnken Design to investigate the influence of three independent variables at three different levels: particle mean size and polydispersity index. The optimized probiotic-loaded alginate particles were added to orange juice samples. The viability of the probiotic strain, both as free and microencapsulated, was evaluated in orange juice stored at 5°C for 35 days. Morphology and size of probiotic-loaded alginate particles were found suitable for incorporation into juice. TEM analysis revealed that unloaded systems were clustered as nanoparticles (CL_NP), while the loaded sample appeared as a coated system (Coated_LGG). Microbiological evaluation revealed that the encapsulation assured the survival of Coated_LGG, with a reduction of less than 1-unit log in cellular density after 35 days of refrigerated storage in orange juice. Results indicated that the encapsulated bacteria did not affect the macroscopic properties neither the microbiological characteristic of orange juice; thus, it can be proposed as functional food.

Viability of microencapsulated Lactobacillus acidophilus by complex coacervation associated with enzymatic crosslinking under application in different fruit juices

The objective of this study was to produce microcapsules containing Lactobacillus acidophilus LA-02 by complex coacervation followed by crosslinking with transglutaminase and to evaluate the effect of their addition on different fruit juices, as well as the probiotic viability of L. acidophilus and its effect on fruit juices during storage. To this end, L. acidophilus was microencapsulated by complex coacervation, followed by crosslinking with transglutaminase at different concentrations. Probiotics, in their free and microencapsulated forms, were added to orange juice and apple juice at concentrations of 10% and 30%. The obtained microcapsules were characterized in terms of morphology. The viability of probiotics and the effects of their addition on fruit juices were assessed and the juices characterized (with respect to pH and total soluble solids) during 63 days of storage at 4 °C. Orange juice proved to be more suitable for the addition of probiotics, and the survival of probiotics was directly related to pH. The microcapsules had a protective effect on L. acidophilus, prolonging their survival, and the crosslinking process proved to be adequate and promising, ensuring probiotic viability. Thus, the complex coacervation process associated with induced enzymatic crosslinking provided protection for L. acidophilus in different fruit juices, showing an adequate methodology for adding probiotics to this adverse food matrix, guaranteeing the survival of L. acidophilus for up to 63 days, and generating products with innovative and promising probiotic appeal.

Safety of Probiotics: Functional Fruit Beverages and Nutraceuticals

Over the last decade, fruit juice consumption has increased. Their rise in popularity can be attributed to the belief that they are a quick way to consuming a dietary portion of fruit. Probiotics added to fruit juices produce various bioactive compounds, thus probiotic fruit juices can be considered as a new type of functional foods. Such combinations could improve nutritional properties and provide health benefits of fruit juices, due to delivering positive health attributes from both sources (fruit juices and probiotics). However, this review discusses the other side of the same coin, i.e., the one that challenges general beliefs that probiotics are undoubtedly safe. This topic deserves more acknowledgments from the medical and nutritional literature, as it is highly important for health care professionals and nutritionists who must be aware of potential probiotic issues. Still, clinical trials have not adequately questioned the safety of probiotics, as they are generally considered safe. Therefore, this reviews aims to give an evidence-based perspective of probiotic safety, focusing on probiotic fruit beverages and nutraceuticals, by providing documented clinical case reports and studies. Finally, the paper deals with some additional insights from the pharmacological and toxicological point of views, such as pharmacological repercussions of probiotics on health.

Design and Characterization of a Novel Fermented Beverage from Lentil Grains

The experimental activities carried out in this study aimed at designing a lentil-based beverage rich in soluble and digestible proteins. In order to extract soluble proteins, lentil grains were soaked in water overnight, blended, treated with proteolytic enzymes and fermented with Lactobacillus strains. Protein enzymatic hydrolysis, carried out with four commercial food grade enzyme preparations, showed that bromelin, at the enzyme to substrate ratio of 10%, was the best solution to produce this novel beverage. Even though the seven Lactobacillus strains were all able to ferment aqueous extract within 24 h, L. acidophilus ATCC 4356, L. fermentum DSM 20052 and L. paracasei subsp. paracasei DSM 20312 showed the highest growth rate and the lowest pH values. In fermented lentil-based beverages, the antinutritional factor phytic acid decreased up to 30%, similarly, the highest reduction in raffinose oligosaccharides content reached about 12% the initial concentration. It is worthy of note that the viable density of all strains remained higher than 7 log cfu/mL after 28 days of cold storage. The results here reported show for the first time the possibility to obtain a probiotic lentil-based beverage rich in soluble proteins, peptides and amino acids with low content in main antinutritional factors.

Functional Efficacy of Probiotic Lactobacillus sanfranciscensis in Apple, Orange and Tomato Juices with Special Reference to Storage Stability and In Vitro Gastrointestinal Survival

There is an increasing demand for non-dairy probiotic carriers such as fruit and vegetable juices. Probiotic Lactobacillus sanfranciscensis is predominantly used in the bakery industry, and its efficacy in fruit juices has not been studied sufficiently. Additionally, support from the carrier matrices for maintaining probiotic viability and gastrointestinal tolerance is important in selecting suitable vehicles for probiotic delivery. Three different non-dairy carrier juices (apple, orange and tomato) were tested for their ability to maintain L. sanfranciscensis viable during four weeks of refrigerated storage (4 °C). Their potential protection of L. sanfranciscensis against in vitro gastrointestinal digestion was also evaluated. Results indicated that the probiotics viability in all three juice samples met the recommended level for probiotic food (>106–107 cfu/mL) at the end of storage. However, all three juice samples showed a comparatively lower protective effect (p < 0.05) on the viability of L. sanfranciscensis when exposed to simulated gastric juice (pH = 2) at the end of 60 min and simulated intestinal juice with 0.3% (w/v) bile salt (pH = 8) at the end of 240 min exposure. In general, the three tested juices can be regarded as the potential non-dairy based carriers for L. sanfranciscensis. The future research is needed to improve the modification of the probiotic carriers in order to prolong the viability of L. sanfranciscensis during the gastrointestinal digestion.

A new delivery system based on apple pomace-pectin gels to encourage the viability of antimicrobial strains

This work was aimed to investigate the concept of the valorization of apple processing by-products to produce a new preservation system based on apple pomace gels to encourage the viability of antimicrobial Lactobacillus strains. A high frequency (850 kHz) low power (1.3 W/cm²) ultrasound-stimulated cavitation was used for the structure modulating of gels under low-temperature (50 ℃) conditions. Medium esterified apple pectin was added to apple pomace to improve its texture properties and stability. The monitoring of the process of gelation was performed by using acoustic technique and method, based on the measurement of the distance (parameter h, mm) traveled by a free-falling module. The obtained data were then compared to gel texture measurements. The results suggest that low power ultrasound leads to a reduced jelly mass stickiness and increased gel hardness, compared to the thermally treated sample. The immobilization of probiotic cells in low pectin apple pomace gels did not sufficiently protect the microorganisms. The higher viability of immobilized Lactobacillus paracasei (54-77%) compared to L. plantarum (43-59%) was recorded after incubation at acidic conditions (pH 2.0). The most suitable system for preserving bacterial cells during storage can be the apple pomace-pectin gel containing up to 53% pectin as a stabilizer retaining 84% of viable cells after one-month storage at 4 ℃. The apple pomace-pectin hydrogels with gelation rate (dh/dt) of 0.03-0.05 mm/s can be used for the preservation of bacterial cells as a suitable functional ingredient for food.

Probiotic Beverage From Pineapple Juice Fermented With Lactobacillus and Bifidobacterium Strains

Pineapple is an economically significant plant and the third most important fruit crop in the tropical and subtropical regions of the world. In this study, fermentation of pineapple juice with probiotic bacteria Lactobacillus and Bifidobacterium strains as well as changes of some properties in the beverage during storage were investigated. All tested strains exhibited good growth properties on pineapple juice without supplementation of any nutrient compounds. After 24 h fermentation, the cell counts of lactobacilli passed the level of 5^*10⁹ cfu/ml, while the cell number of bifidobacteria reached a level of 10⁹ cfu/ml. The highest volumetric productivity (3.5^*10⁸ cfu/ml^*h) was observed in L. plantarum 299V. The ratios of lactic acids to acetic acids in the cases of L. plantarum 299V and L. acidophilus La5 were 5.37 and 9.91, respectively. In the case of B. lactis Bb-12, the concentrations of lactic acid and acetic acid were 6 mM and 23 mM in natural juices, and 15 and 21 mM in the case of supplementation with prebiotics at the 16^th h of fermentation, respectively. Additionally, supplementation with prebiotics at the initiation of fermentation resulted 7 mM lactic acid and 23 mM acetic acid at the end of fermentation. Fructose was the most preferred sugar for both lactobacilli and bifidobacteria. Both total phenolic content and antioxidant capacity increased slightly during fermentation and dropped during the storage period. The microbial population did not change significantly during the first month of storage. After the storage period (2 months), the probiotic bacteria lost about 0.11 log cfu/ml viability after treatment with 0.3% pepsin for 135 min, and a further 0.1 log cfu/ml after treatment with 0.6% bile salts. These values were 10 times higher than data from the fresh fermented pineapple juice. Our results are very promising and may serve as a good base for developing probiotic pineapple juice.

Patulin removal from synbiotic apple juice using Lactobacillus plantarum ATCC 8014

AIMS

The aim of this study was to evaluate the elimination of patulin (PAT) by Lactobacillus plantarum ATCC 8014 from artificially contaminated apple juice and its dependence on prebiotic, citric acid and ascorbic acid content.

METHODS AND RESULTS

A central composite design was used for studying each of the three factors at five levels to find the optimum concentrations. The results showed that inserting 2·3% (w/v) fructooligosaccharide, 213 mg l^-1 ascorbic acid and 1·4 g l^-1 citric acid to apple juice with inoculating 3·6 × 10¹¹ CFU per ml, L. plantarum improved the efficiency of PAT removal to 95·91% during 6 weeks cold storage. SDS-PAGE of cell surface proteins of probiotics revealed that surface layer proteins have an important role in PAT removal from apple juice. No significant difference was observed in the flavour and colour of the optimized synbiotic apple juice and in the control sample until 3 weeks of cold storage.

CONCLUSION

Lactobacillus plantarum ATCC 8014 is capable of PAT removal from artificially contaminated synbiotic apple juice.

SIGNIFICANCE AND IMPACT OF THE STUDY

Synbiotic apple juice artificially contaminated with PAT will be safe for consumers after the first day of probiotic inoculation; and surface layer proteins of probiotic cells are responsible for PAT removal.

Food Matrix Design for Effective Lactic Acid Bacteria Delivery

The range of foods featuring lactic acid bacteria (LAB) with potential associated health benefits has expanded over the years from traditional dairy products to meat, cereals, vegetables and fruits, chocolate, etc. All these new carriers need to be compared for their efficacy to protect, carry, and deliver LAB, but because of their profusion and the diversity of methods this remains difficult. This review points out the advantages and disadvantages of the main food matrix types, and an additional distinction between dairy and nondairy foods is made. The food matrix impact on LAB viability during food manufacturing, storage, and digestion is also discussed. The authors propose an ideal hypothetical food matrix that includes structural and physicochemical characteristics such as pH, water activity, and buffering capacities, all of which need to be taken into account when performing LAB food matrix design. Guidelines are finally provided to optimize food matrix design in terms of effective LAB delivery.

Effect of encapsulation on the stability and survivability of Enterococcus faecium in a non-dairy probiotic beverage

The main objectives of this work were to study the survivability of five probiotic lactobacilli strains in sour cherry juice and citrate buffer with similar pH values (pH 3.5) during storage at 4 ℃ as well as to encapsulate the strain with the least survival in calcium alginate beads. Enterococcus faecium from probiotic strains in sour cherry juice exhibited the least survival; therefore, this strain was selected for studying the protective effect of microencapsulation in calcium alginate beads. Microencapsulated probiotic cells were incorporated into sour cherry juice and then exposed to harsh conditions (e.g. heat treatment, low pH, and simulated gastrointestinal fluids). Changes in the probiotic survivability, pH and titratable acidity of sour cherry juice were monitored during 60 d. D-values of free cells, calculated at 60, 70 and 80 ℃, were 4.87, 1.48 and 0.43 min, respectively; while, those of microencapsulated cells were 9.41, 3.73 and 1.26 min, respectively. The decrease in the number of free E. faecium after exposure to low pH values (e.g. 2.5, 2 and 1.5) was 2.81, 3.74 and 4.18 log CFU/mL, respectively. Freshly prepared and 30-d old microencapsulated cells, maintained at 4 ℃ in sour cherry juice, showed 1.31, 2.13, 2.37 and 2.19, 2.46, 3.26 log CFU/mL reduction after exposure to similar pH conditions, respectively. The number of free and encapsulated probiotic cells after incubation in simulated gastric and gastrointestinal fluids was 5.86 and 4.81 and 8.05 and 6.61 log CFU/mL, respectively. The sensory attributes of probiotic sour cherry juice samples containing encapsulated cells were better than those fortified with free probiotics.

The performance of five fruit-derived and freeze-dried potentially probiotic Lactobacillus strains in apple, orange, and grape juices

BACKGROUND

This study assessed the survival of the fruit-derived and freeze-dried L. plantarum 49, L. brevis 59, L. paracasei 108, L. fermentum 111 and L. pentosus 129 strains during frozen storage and when incorporated into apple, orange, and grape juice stored under refrigeration. Physicochemical parameters of juices containing the freeze-dried Lactobacillus strains and the survival of the test strains in the fruit juices during in vitro digestion were also evaluated.

RESULTS

No decreases in survival rates (log N/log N0) of the freeze-dried cells were observed in up to 1 month of storage. The survival rates of the freeze-dried strains L. plantarum 49 and L. paracasei 108 were > 0.75 in up to 4 months of storage. All freeze-dried strains exhibited survival rates of >0.75 in up to 2 weeks of storage in apple juice; only L. plantarum 49 and L. paracasei 108 showed similar survival rates in orange and grape juices in up to 2 weeks of storage. The contents of the monitored organic acids or sugars during storage varied depending on the added strain and the type of fruit juice. At the end of in vitro digestion, L. brevis 59, L. paracasei 108 and L. fermentum 111 showed survival rates of >0.80 in apple juice.

CONCLUSION

Apple juice was the best substrate for the survival of the tested freeze-dried Lactobacillus strains over time. L. paracasei 108 and L. plantarum 49 were the strains presenting the best performance for incorporation in potentially probiotic fruit juices. © 2018 Society of Chemical Industry.

Beet and orange mixed juices added with Lactobacillus acidophilus

Purpose

The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture.

Design/methodology/approach

Two formulations of probiotic beet and orange mixed juices (1:1 e 1:2 v/v) were prepared, stored at 4°C for 28 days and were evaluated for probiotic survival, physicochemical stability, antioxidant activity and sensory acceptance. The probiotic culture was added in a lyophilized form and was not propagated in culture media or juice.

Findings

Physicochemical characteristics (pH, titratable acidity, total soluble solids and color) and antioxidant activity showed no undesirable alterations during storage. The number of probiotics followed established minimum requirement for probiotic foods (109 CFU/200mL) during the 28 days of storage. The juices showed good sensory acceptance and purchase intention, especially regarding the color of the product.

Practical implications

The beet and orange mixed juices are suitable carriers for L. acidophilus with a shelf life of at least 28 days at 4°C.

Originality/value

Direct addition of the probiotic culture could result in high probiotic survival in mixed juices, dispensing the propagation step.

A prebiotic mixture improved Lactobacillus acidophilus and Bifidobacterium animalis gastrointestinal in vitro resistance in petit-suisse

Advantageous addition of a prebiotic mixture in petit-suisse cheese, improved the probiotic strains survival under gastrointestinal conditions simulated in vitro throughout 28 days of storage.

Activities of free and encapsulated Lactobacillus acidophilus LA5 or Lactobacillus casei 01 in processed longan juices on exposure to simulated gastrointestinal tract

BACKGROUND

Fruit drinks containing probiotics are gaining interest in the global marketplace. For example, longan juice, containing carbohydrate and various bioactive components, is a potentially health-promoting beverage as well as probiotic carrier for human consumption. In this study, high-pressure and thermal processes were applied to eliminate competitive micro-organisms in longan juice prior to the addition of Lactobacillus acidophilus LA5 or Lactobacillus casei 01. The activities of these probiotics in a simulated gastrointestinal tract were also investigated.

RESULTS

Encapsulated probiotics could survive in the acidic environment of the stomach and small intestine, while the free cells were completely eliminated. In the colon experiment, the influence of encapsulated L. casei 01 on colon lactobacilli was significantly greater than that of encapsulated L. acidophilus LA5. Both encapsulated probiotics suspended in processed longan juices led to extensive increases in the formation of lactic acid and short-chain fatty acids (SCFA). Acetate was the major SCFA produced by colon bacteria, followed by propionate and butyrate. The discernible clear zone suggested that L. casei 01 provided greater antibacterial activity than L. acidophilus LA5.

CONCLUSION

Both encapsulated probiotics along with processed longan juice led to significant increases in colon lactobacilli, lactic acid and SCFA formation.

Non-dairy probiotic beverages: the next step into human health

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit to the host. The two main genera of microorganisms indicated as sources of probiotic bacteria are Lactobacillus and Bifidobacterium. Historically used to produce fermented dairy products, certain strains of both genera are increasingly utilised to formulate other functional foods. As the consumers’ understanding of the role of probiotics in health grows, so does the popularity of food containing them. The result of this phenomenon is an increase in the number of probiotic foods available for public consumption, including a rapidly-emerging variety of probiotic-containing non-dairy beverages, which provide a convenient way to improve and maintain health. However, the composition of non-dairy probiotic beverages can pose specific challenges to the survival of the health conferring microorganisms. To overcome these challenges, strain selection and protection techniques play an integral part in formulating a stable product. This review discusses non-dairy probiotic beverages, characteristics of an optimal beverage, and commonly used probiotic strains, including spore-forming bacteria. It also examines the most recent developments in probiotic encapsulation technology with focus on nano-fibre formation as a means of protecting viable cells. Utilising bacteria's natural armour or creating barrier mechanisms via encapsulation technology will fuel development of stable non-dairy probiotic beverages.