Development and physico-chemical characterization of microencapsulated bifidobacteria in passion fruit juice: A functional non-dairy product for probiotic delivery

Alginate coatings applied on apple cubes as a vehicle for Lacticaseibacillus casei: probiotic viability and overall quality of a new functional product

BACKGROUND

Worldwide, vegan and vegetarian lifestyles, as well as food allergies and intolerance (e.g. lactose intolerance and milk protein allergy) demand the development of alternatives to dairy-based probiotic foods. In the present study, probiotic Lacticaseibacillus casei CECT 9104 was added to alginate-based edible coatings enriched with inulin and oligofructose and applied to fresh-cut apple. Microbiological, physicochemical and sensory quality parameters of the apple cubes were monitored during 8 days of refrigerated storage. Lacticaseibacillus casei was tested for its antagonistic effect against inoculated Listeria innocua and Escherichia coli O157:H7. The viability of the probiotic strain during refrigerated storage and after simulated gastrointestinal digestion (GID) was evaluated.

RESULTS

After 8 days of storage, 9.52-9.64 log colony-forming units (CFU) g-1 of L. casei were detected in apple samples. The functional apple cubes retained 8.31-8.43 log CFU g-1 of the probiotic after GID, without a significant effect of prebiotic addition. The microbiological quality and nutritional properties were maintained by the use of active coatings, whereas the sensory quality decreased after 8 days of storage. A bactericidal effect was exerted by the probiotic strain loaded in the coating against L. innocua artificially inoculated on apple cubes. Escherichia coli O157:H7 counts were reduced by 2.5 log after 8 days.

CONCLUSION

This study has demonstrated the suitability of apple cubes as an alternative matrix to milk for carrying probiotic L. casei CECT 9104 and prebiotics, offering a promising alternative for the development of plant-based functional foods. © 2024 Society of Chemical Industry.

Stability and expression of K-ras mimotopes in freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder during storage in vacuum packaging

AIMS

This study aims to evaluate the storage stability of the freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder expressing K-ras (Kristen rat sarcoma viral oncogene homolog) mimotopes targeting colorectal cancer in vacuum packaging.

METHODS AND RESULTS

The freeze-dried L. lactis-fermented milk powder stored in 4-ply retortable polypropylene (RCPP)-polyamide (PA)-aluminium (AL)-polyethylene terephthalate (PET) and aluminium polyethylene (ALPE) was evaluated throughout 49 days of accelerated storage (38°C and 90% relative humidity). The fermented milk powder stored in 4-ply packaging remained above 6 log10 CFU g-1 viability, displayed lower moisture content (6.1%), higher flowability (43° angle of repose), water solubility (62%), and survivability of L. lactis after simulated gastric and intestinal digestion (>82%) than ALPE packaging after 42 days of accelerated storage. K-ras mimotope expression was detected intracellularly and extracellularly in the freeze-dried L. lactis-fermented milk powder upon storage.

CONCLUSIONS

This suggests that fermented milk powder is a suitable food carrier for this live oral vaccine.

Application of inulin for the formulation and delivery of bioactive molecules and live cells

Inulin is a fructan biosynthesized mainly in plants of the Asteraceae family. It is also found in edible vegetables and fruits such as onion, garlic, leek, and banana. For the industrial production of inulin, chicory and Jerusalem artichoke are the main raw material. Inulin is used in the food, pharmaceutical, cosmetic as well biotechnological industries. It has a GRAS status and exhibits prebiotic properties. Inulin can be used as a wall material in the encapsulation process of drugs and other bioactive compounds and the development of their delivery systems. In the review, the use of inulin for the encapsulation of probiotics, essential and fatty oils, antioxidant compounds, natural colorant and other bioactive compounds is presented. The encapsulation techniques, materials and the properties of final products suitable for the delivery into food are discussed. Research limitations are also highlighted.

Lactic acid bacteria viability in different refrigerated food matrices: a systematic review and Meta‑analysis

The aim of this systematic review and meta-analysis was to determine which variables affect the viability of lactic acid bacteria (LAB) added to different types of refrigerated foods during the first 28 days. Scopus, ScienceDirect, PubMed and Cochrane Central Register of Reviews databases were searched from 1997 to April 2022. A total of 278 studies, which showed randomized and controlled experiments published in peer reviewed journals, were included. The viability of LAB in different moments during the storage process was synthesized as mean point estimate (MPE) via random-effects meta-analyses and the effect of multiple factors on the LAB´s viability was evaluated by multiple meta-regression. The meta-analysis showed that the decrease in LAB viability will be more abrupt the greater the initial dose. The physical structure of food may influence bacterial viability. Fruit was the type of product that most quickly lost viability. Co-culture of two or more species did not affect viability. Preservation methods had an unfavorable effect and prebiotics had a beneficial effect on bacterial viability. Viability was genus dependent. The data obtained in this study provide an overview of the factors to be taken into account for the design of new foods.

Nutraceutical Combinational Therapy for Diarrhoea Control with Probiotic Beverages from Fermented Fruits, Vegetables and Cereals to Regain Lost Hydration, Nutrition and Gut Microbiota

This article deals with the condition of irregular bowel movements known as diarrhoea, its pathology, symptoms and aetiology. The information has been presented on causes of diarrhoea that include gut infections, food intolerances and allergies to certain ingredients, problems in the gastrointestinal tract like irritable bowel syndrome, inflammatory bowel disease and, the condition of dysbiosis which occurs due to long-term use of antibiotics, or other medicines, etc. Most cases of diarrhoea can be resolved without needing medical treatment; however, it is still important to avoid dehydration of the body and use some supplements to get necessary nutrients which are lost with frequent bowel movements before they can get absorbed and assimilated in the gastrointestinal tract. Probiotic products are reported as natural therapeutic agents, which can reduce the risk of diarrhoea in both adults and children. The intake of dietary fluid supplements in the form of fermented beverages containing probiotic strains could help in diarrhoea control. The patient would achieve benefits with the consumption of these functional beverages in three ways-by regaining lost fluids to the body, supplementing beneficial gut bacteria to restore diversity in gut microbiota, which was disturbed in the condition of diarrhoea as well as regaining a source of quick nutrition to recoup energy.

Production and characterization of nondairy gluten-free fermented beverage based on buckwheat and lentil

The present study aimed to optimize the formulation of buckwheat/lentil gluten-free beverages fermented with Lactobacillus plantarum and Bifidobacterium bifidum. Physicochemical parameters of 14 different beverages, such as pH, acidity, total solids, ash, total phenol content, antioxidant activity, and sensory test, were assessed after 24 h of fermentation. The results showed that the numbers of viable cells of lactobacilli and bifidobacteria on the first day of the experiment were 9.9 and 9.6 log (CFU ml-1), respectively, which were over 9 log (CFU ml-1). During 24 h from the fermentation, the number of viable cells for all beverages decreased, which reached an average probiotic count of 8.81 log (CFU ml-1) that was statistically significantly different from the probiotic count before fermentation (p < .05). Cell viability was evaluated and shelf life was estimated during 15-day refrigerated storage. At the end of the storage (15th day), the beverages contained an average of 8.4 log (CFU ml-1) of live lactobacilli cells and 7.8 log (CFU ml-1) of viable bifidobacterial cells. The optimized levels of independent factors for sprouted buckwheat and lentil flours were 51.96% and 48.04%, respectively. The optimized probiotic beverage was contained 0.25 (% lactic acid) acidity, 5.7 pH, 7.9% total solids, 0.4% ash, 41.02% DPPH, 26.96 (mg GAE/ml) phenol compounds, and 8.65 log (CFU ml-1) probiotic count. The optimized beverage had distinct organoleptic properties on day 15 of refrigerated storage. This study showed that Bifidobacterium bifidum can be used for the development of potentially probiotic beverage with sprouted buckwheat and lentil.

Microencapsulation and Application of Probiotic Bacteria Lactiplantibacillus plantarum 299v Strain

Microencapsulation is an up-and-coming technology for maintaining the viability of probiotics. However, the effect of core-to-wall ratios and ratios of polysaccharides on the protection of the Lactiplantibacillus plantarum 299v strain has not been deeply discussed. Lyophilization of the Lp. plantarum 299v strain was conducted, and different core-to-wall ratios and ratios of maltodextrin (MD) and resistant starch (RS) were applied. Results demonstrated that the content of MD and RS had an influence on the yield and bulk density in both core-to-wall ratios (1:1 and 1:1.5). In addition, samples coated with a core-to-wall ratio of 1:1.5 had significantly higher viability than those coated with a core-to-wall ratio of 1:1. Moreover, samples coated with core-to-wall ratios of 1:1 and MD:RS 1:1, as well as core-to-wall ratios of 1:1.5 and MD:RS 3:1, had the highest cell number after simulated gastric fluid and simulated intestinal fluid testing, respectively. Furthermore, the optimal formulation for the application of microencapsulated Lp. plantarum 299v in apple juice (serving as a functional beverage) is listed as follows: core-to-wall ratios of 1:1 and MD:RS 1:1, with the fortification method, and stored at 4 °C. After 11 weeks of storage, the cell count was 8.28 log (CFU/mL). This study provided a strategy for Lp. plantarum 299v to achieve high viability in long-term storage and provides an application in functional apple beverages.

Passion fruit (Passiflora spp.) pulp: A review on bioactive properties, health benefits and technological potential

The Passiflora genus (Passifloraceae family) extends worldwide, but it is mainly found in the Americas. The present review aimed to select the main reports published over the last 5 years involving the chemical composition, health benefits, and products obtained from the pulps of Passifora spp. The pulps of at least 10 species of Passiflora have been studied presenting different classes of organic compounds, especially phenolic acids, and polyphenols. The main bioactivity properties include antioxidant and in vitro α-amylase and α-glucosidase enzyme inhibition. These reports highlight the potential of Passiflora for the development of a variety of products, especially fermented and non-fermented beverages, as well as foods to attend a demand for non-dairy products. In general, these products are prominent source of probiotic bacteria resistant to in vitro gastrointestinal simulation, representing an alternative for intestinal microbiota regulation. Therefore, sensory analysis is encouraging herein, as well as in vivo tests to enable the development of high value pharmaceuticals and food products. The patents confirm the great interest in research and products development in different food technology areas, as well as in biotechnology, pharmacy, and materials engineering.

Copper(II) and Cobalt(II) Complexes Based on Abietate Ligands from Pinus Resin: Synthesis, Characterization and Their Antibacterial and Antiviral Activity against SARS-CoV-2

Co-abietate and Cu-abietate complexes were obtained by a low-cost and eco-friendly route. The synthesis process used Pinus elliottii resin and an aqueous solution of CuSO₄/CoSO₄ at a mild temperature (80 °C) without organic solvents. The obtained complexes are functional pigments for commercial architectural paints with antipathogenic activity. The pigments were characterized by Fourier-transform infrared spectroscopy (FTIR), mass spectrometry (MS), thermogravimetry (TG), near-edge X-ray absorption fine structure (NEXAFS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and colorimetric analysis. In addition, the antibacterial efficiency was evaluated using the minimum inhibitory concentration (MIC) test, and the antiviral tests followed an adaptation of the ISO 21702:2019 guideline. Finally, virus inactivation was measured using the RT-PCR protocol using 10% (w/w) of abietate complex in commercial white paint. The Co-abietate and Cu-abietate showed inactivation of >4 log against SARS-CoV-2 and a MIC value of 4.50 µg·mL^-1 against both bacteria Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The results suggest that the obtained Co-abietate and Cu-abietate complexes could be applied as pigments in architectural paints for healthcare centers, homes, and public places.

Mixed fermentation and electrospray drying for the development of a novel stabilized wheat germ powder containing highly viable probiotic cultures

Nondairy fermented probiotic powder was developed based on stabilized wheat germ through mixed fermentation (Lactobacillus acidophilus and Lactobacillus plantarum) and electrospraying process. In the first step, the effect of mixed fermentation on lipase and lipoxygenase activity of wheat germ was investigated. The results showed a significant reduction in the activity of both enzymes (82.72% for lipase and 72% for lipoxygenase), therefore, mixed fermentation effectively stabilizes the wheat germ. In the next step, after the preparation of the solutions for drying process and investigating the physical properties (surface tension, electrical conductivity, and viscosity) of the solutions, the electrosprayability of the samples was evaluated at different conditions and revealed that 18 kV applying voltage, 0.3 flow rate, and 12 cm distance between tip to collector was the best for electrospraying the 20% solution of fermented wheat germ with morphologically most semi-uniform particles. Finally, the viability of the probiotics after drying process and during the storage at 25°C was examined. The number of initial cells counted as 14.48 ± 0.2 log cfu/g and the viability studies showed 0.55 log cfu/g decrease in the number of viable bacteria from initial count as a result of the electrospraying process. Furthermore, 7.86 ± 0.03 log cfu/g in freeze-dried and 9.05 ± 0.45 log cfu/g in electrosprayed samples survived after 70 days of storage.

Spray Drying Encapsulation of Pediococcus acidilactici at Different Inlet Air Temperatures and Wall Material Ratios

Pediococcus acidilactici has gained research and commercial interest due to its outstanding probiotic properties, yet its survival during storage and consumption requires improvement. This study aims to enhance P. acidilactici survival using spray drying encapsulation. Different inlet air temperatures (120 °C, 150 °C, and 170 °C) and whey protein isolate (WPI):gum arabic (GA) ratios (1:1, 3:1, 1:3) were tested. Cell viability was significantly (p < 0.05) affected by the inlet temperature but not the WPI:GA ratio. Increasing the inlet temperature to 170 °C significantly decreased P. acidilactici viability by 1.36 log cycles, from 8.61 log CFU/g to 7.25 log CFU/g. The inlet temperature of 150 °C resulted in a powder yield (63.12%) higher than at 120 °C (58.97%), as well as significantly (p < 0.05) lower moisture content (5.71%) and water activity (aw 0.21). Viable cell counts in all encapsulated P. acidilactici were maintained at 5.24−6.75 log CFU/g after gastrointestinal tract (GIT) simulation, with WPI:GA of 3:1 and inlet temperature 150 °C having the smallest log reduction (0.3 log cycles). All samples containing different WPI:GA ratios maintained sufficient viability (>7 log CFU/g) during the first three weeks of storage at 25 °C. These results could provide insights for further developing P. acidilactici as commercial probiotic products.

Green Coffee Extract Microencapsulated: Physicochemical Characteristics, Stability, Bioaccessibility, and Sensory Acceptability through Dairy Beverage Consumption

This study aimed to investigate the effect of spray drying (SD) and freeze-drying (FD) on the microencapsulation of green coffee extracts by using polydextrose (PD) and inulin (IN) as encapsulating agents and their physicochemical, bioactive compounds' stability, phenolic compounds' bioaccessibility after digestion, and sensory effects in unfermented dairy beverages. The extract encapsulated with IN by FD had lower moisture content, water activity, and hygroscopicity, while particles encapsulated by SD exhibited a spherical shape and the structure of the FD products was irregular. No difference was observed in phenolic compounds' bioaccessibility. Dairy beverages with added encapsulated extracts had higher total phenolic content and antioxidant activity. Microencapsulation allowed a controlled release of the bioactive compounds with an increase in the content of caffeine, chlorogenic acid, and trigonelline during storage. The dairy beverage with added extract encapsulated with IN by FD had the highest scores of acceptability regarding the overall impression and purchase intent.

Microencapsulation of Probiotics for Food Functionalization: An Update on Literature Reviews

Functional foods comprise the largest growing food category due to both consumer demands and health claims by manufacturers. Probiotics are considered one of the best choices for meeting these demands. Traditionally, the food vehicle for introducing probiotics to consumers was dairy products, and to expand the benefits of probiotics for a wider range of consumers, the need to use other food items was essential. To achieve this goal while maximising the benefits of probiotics, protection methods used during food processing were tackled. The microencapsulation of probiotics is a promising methodology for achieving this function. This review highlights the use of the microencapsulation of probiotics in order to functionalise food items that initially were not considered suitable for probiotication, such as baked products, or to increase their functionality such as dairy products. The co-microencapsulation of probiotics with other functional ingredients such polyphenol, prebiotics, or omega-3 is also highlighted.

Natural sources and encapsulating materials for probiotics delivery systems: Recent applications and challenges in functional food development

Probiotics are known as the live microorganisms which upon adequate administration elicit a health beneficial response inside the host by decreasing the luminal pH, eliminating the pathogenic bacteria in the gut as well as producing short chain fatty acids (SCFA). With advancements in research; probiotics have been explored as potential ingredients in foods. However, their use and applications in food industry have been limited due to restrictions of maintaining the viability of probiotic cells and targeting the successful delivery to gut. Encapsulation techniques have significant influence on increasing the viability rates of probiotic cells with the successful delivery of cells to the target site. Moreover, encapsulating techniques also prevent the live cells from harsh physiological conditions of gut. This review discusses several encapsulating techniques as well as materials derived from natural sources and nutraceutical compounds. In addition to this, this paper also comprehensively discusses the factors affecting the probiotics viability and evaluation of successful release and survival of probiotics under simulated gastric, intestinal conditions as well as bile, acid tolerant conditions. Lastly applications and challenges of using encapsulated bacteria in food industry for the development of novel functional foods have also been discussed in detail too. Future studies must include investigating the use of encapsulated bacterial formulations in in-vivo models for effective health beneficial properties as well as exploring the mechanisms behind the successful release of these formulations in gut, hence helping us to understand the encapsulation of probiotic cells in a meticulous manner.

Nutrition and Health through the Use of Probiotic Strains in Fermentation to Produce Non-Dairy Functional Beverage Products Supporting Gut Microbiota

Pure viable strains of microorganisms identified and characterised as probiotic cultures are used in the fermentation process to prepare functional beverages. The fermented probiotic products can be consumed as a source of nutrition and also for the maintenance of healthy gut microbiota. The functional beverages contain the substrates used for the preparation of product with a specific culture or a mixture of known strains used to perform the fermentation, hence these drinks can be considered as a healthy formulation of synbiotic products. If a beverage is prepared using agriculturally sourced materials, the fermented substrates with their oligosaccharides and fiber content act as prebiotics. Both the components (probiotic strain/s and prebiotic substrate) exist in a synergistic relationship in the product and contribute to several benefits for nutrition and gut health. The preparation of such probiotic beverages has been studied using non-dairy-based materials, including fruits, vegetables, nuts, grains, and cassava, a staple diet source in many regions. The consumption of beverages prepared with the use of probiotics, which contain active microbial cells and their metabolites, contributes to the functional properties of beverages. In addition, the non-dairy probiotic products can be used by consumers of all groups and food cultures, including vegans and vegetarians, and particularly consumers with allergies to dairy-based products. The aim of this article is to present a review of published research highlighting specific probiotic strains, which have the potential to enhance sustainability of healthy GIT microbiota, used in the fermentation process for the preparation of non-dairy beverages.

Micro-Encapsulation of Phytochemicals in Passion Fruit Peel Waste Generated on an Organic Farm: Effect of Carriers on the Quality of Encapsulated Powders and Potential for Value-Addition

The passion (Passiflora edulis Sims) fruit peel is rich in phenolics and other bioactive compounds and has great potential as a natural food preservative. The present study investigated the value-adding potential of passion fruit peel waste generated on an organic farm. The effect of carriers in encapsulating the peel extract to develop a polyphenolic-rich powder was investigated. The passion fruit peel extracts were prepared using 70% ethanol (1:10 w/v), and encapsulated using waxy starch (WS), gum arabic (GA), and maltodextrin (MT) before freeze-drying. The effects of carriers on the passion fruit peel powder (PFPP) production yield, physicochemical, rheological, phytochemical, and antioxidant properties were investigated. GA-and MT-encapsulated powders had better physical, phytochemical, and antioxidant properties, including yield, total soluble solids, solubility, bulk density, total phenolic content, and ferric reducing antioxidant powder. A total of 18 metabolites, including phenolic acids (10), flavonoids (6), and stilbenes (2), were tentatively identified in all the PFPP samples, with WS exhibiting a higher concentration of the compounds compared to GA and MT. Our results indicated that no single carrier was associated with all the quality attributes; therefore, better results could be produced by compositing these carriers. Nonetheless, our results highlight the potential of passion fruit peels as a source of polyphenols and functional ingredient in formulating natural food additives.

Improvement of stability and antioxidant activity of wheat germ by mixed fermentation versus single fermentation

Wheat germ is a high-nutrient by-product from the milling industry with very limited optimal consumption due to its short shelf life. The severe activity of endogenous lipase and lipoxygenase is associated with the release of fatty acids which are responsible for the rancidity and shelf-life deficiency. Reducing these enzymes activity is essential for prolonging the wheat germ shelf-life. For this purpose, the mixed and simple fermentation of different wheat germ concentrations (10, 15 and 20% w/v wheat germ in distilled water) with Lactobacillus plantarum and Lactobacillus acidophilus was investigated to improve the stability of wheat germ by restraining the activity of the enzymes. Fermentation noticeably reduced the activity of the enzymes in all samples (ranges from 50 to 82.15% for lipase and 55.34 to 72 for lipoxygenase in different treatments), but the mixed-fermented wheat germ with the maximum concentration (20%) achieved the highest reduction level in both enzymes inactivation. Fermentation also resulted in an obvious increase in antioxidant activity from 51.18% in raw wheat germ to more than 72.73% in different samples, which mixed fermentation of 20% wheat germ suspension with the value of 89.76 was ranked first.

Supplementation of Labneh with Passion Fruit Peel Enhanced Survival of E. coli Nissle 1917 during Simulated Gastrointestinal Digestion and Adhesion to Caco-2 Cells

Passion fruit peel powder (PFPP) was used to supplement the probiotic labneh to increase the activity of Escherichia coli Nissle 1917 (EcN) during production and storage. Labneh was manufactured with PFPP (0.5% and 1%) and analyzed at 0, 7, and 15 days of cold storage for postacidification and sensory properties and viability of EcN, survival of EcN to simulated gastrointestinal tract stress, and adhesion potential of EcN to Caco-2 cells. Acidification kinetics during fermentation showed that supplementation with PFPP reduced the time needed to decrease pH and reach the maximum acidification rate. PFPP addition contributed to postacidification of labneh during storage. PFPP had a beneficial effect (p < 0.05) on counts of EcN in labneh during different storage periods. Consumer preference expectations for labneh enriched with PFPP (0.5% and 1%) were higher than those for the control. PFPP provided a significant protective action for EcN during simulated gastrointestinal transit and had a positive effect on EcN adhesion to Caco-2 cells in vitro, although this decreased during storage with labneh. Labneh supplementation with PFPP can be recommended because of the positive effect on EcN viability and the high nutritional value, which may increase the appeal of the product to consumers.

The Role of Microencapsulation in Food Application

Modern microencapsulation techniques are employed to protect active molecules or substances such as vitamins, pigments, antimicrobials, and flavorings, among others, from the environment. Microencapsulation offers advantages such as facilitating handling and control of the release and solubilization of active substances, thus offering a great area for food science and processing development. For instance, the development of functional food products, fat reduction, sensory improvement, preservation, and other areas may involve the use of microcapsules in various food matrices such as meat products, dairy products, cereals, and fruits, as well as in their derivatives, with good results. The versatility of applications arises from the diversity of techniques and materials used in the process of microencapsulation. The objective of this review is to report the state of the art in the application and evaluation of microcapsules in various food matrices, as a one-microcapsule-core system may offer different results according to the medium in which it is used. The inclusion of microcapsules produces functional products that include probiotics and prebiotics, as well as antioxidants, fatty acids, and minerals. Our main finding was that the microencapsulation of polyphenolic extracts, bacteriocins, and other natural antimicrobials from various sources that inhibit microbial growth could be used for food preservation. Finally, in terms of sensory aspects, microcapsules that mimic fat can function as fat replacers, reducing the textural changes in the product as well as ensuring flavor stability.

Survival of Microencapsulated Lactococcus lactis Subsp. lactis R7 Applied in Different Food Matrices

Survival of Lactococcus lactis subsp. lactis R7, microencapsulated with whey and inulin, was analyzed when added to blueberry juice, milk, and cream. For 28 days, cell viability was evaluated for storage (4 °C), simulated gastrointestinal tract (GIT), and thermal resistance. All matrices demonstrated high cell concentration when submitted to GIT (11.74 and 12 log CFU mL^-1), except for the blueberry juice. The thermal resistance analysis proved the need for microencapsulation, regardless of the food matrix. The results indicate that L. lactis R7 microcapsules have potential for application in different matrices and development of new probiotic products by thermal processing.

Emerging Technologies and Coating Materials for Improved Probiotication in Food Products: a Review

From the past few decades, consumers' demand for probiotic-based functional and healthy food products is rising exponentially. Encapsulation is an emerging field to protect probiotics from unfavorable conditions and to deliver probiotics at the target place while maintaining the controlled release in the colon. Probiotics have been encapsulated for decades using different encapsulation methods to maintain their viability during processing, storage, and digestion and to give health benefits. This review focuses on novel microencapsulation techniques of probiotic bacteria including vacuum drying, microwave drying, spray freeze drying, fluidized bed drying, impinging aerosol technology, hybridization system, ultrasonication with their recent advancement, and characteristics of the commonly used polymers have been briefly discussed. Other than novel techniques, characterization of microcapsules along with their mechanism of release and stability have shown great interest recently in developing novel functional food products with synergetic effects, especially in COVID-19 outbreak. A thorough discussion of novel processing technologies and applications in food products with the incorporation of recent research works is the novelty and highlight of this review paper.

Nanoencapsulation of Mandarin Essential Oil: Fabrication, Characterization, and Storage Stability

This study evaluates the combined efficiency of whey protein isolate (WPI) with maltodextrin (MD) and gum arabic (GA), as a delivery system for encapsulating Citrus reticulata essential oil (CEO). The wall materials blended at different rates were produced to obtain seven formulations of nanocapsules (NCEO), namely NCEO-GA, NCEO-MD, NCEO-WPI, NCEO-GA/MD, NCEO-GA/WPI, NCEO-MD/WPI, and NCEO-GA/MD/WPI. The interaction between CEO and WPI was simulated by molecular docking. Findings showed that the physicochemical characteristics and storage stability of formulations containing WPI were considerably improved. The NCEO-GA/MD/WPI formulation demonstrated the optimum values of encapsulation efficiency (92.08%), highest glass transition temperature (79.11 °C), high crystallinity (45.58%), high thermal stability (mass loss at 100 °C < 5%), and also had the highest antioxidant activity and lowest peroxide value after storage. This study demonstrated that combining WPI with MD and GA, as wall material encapsulation, can produce nanocapsules with superior properties to those created using polysaccharides individually.

Evaluation of a strawberry fermented beverage with potential health benefits

Background

Functional fermented beverages are popular worldwide due to their potential to promote health. Starter culture is the main determinant of the final quality and flavor of fermented beverages. The co-cultivation of lactic acid bacteria (LAB) and yeast makes a significant contribution to the safe flavor of fermented beverages. However, the research on the potential of antioxidant, antimicrobial, and anti-biofilm formation of strawberry fermented beverage obtained by combining the LAB and yeast as starter cultures has not been well explored.

Methods

In this study, LAB and yeast were combined as starter culture to obtain strawberry fermented beverage. Fourier transform infrared (FTIR ) spectroscopy was used for the qualitative analysis of the fresh strawberry juice and fermented beverage. From the changes in antioxidant content, free radical scavenging ability, total superoxide dismutase (T-SOD) activity and total antioxidant capacity (T-AOC) to evaluate the antioxidant capacity of fermented beverage in vitro. The antibacterial ability was tested by the Oxford cup method. The biofilms of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538 under fermented beverages treatment was observed by Fluorescence microscope. In addition, sensory analysis was conducted in this study.

Results

In this study, the absorption peaks of Fourier transform infrared between 1,542 cm^-1 and 976 cm^-1, suggest the existence of organic acids, sugars and ethanol. The total phenols and total flavonoids content decreased by 91.1% and 97.5%, respectively. T-SOD activity increased by 33.33%.The scavenging ability of fermented beverage on superoxide anion free radicals was enhanced, and the scavenging ability on DPPH free radicals, hydroxyl free radicals, and ABTS free radicals was weakened. However, the T-AOC increased from 4.15 ± 0.81 to 8.43 ± 0.27 U/mL. Fermented beverage shows antibacterial activity against four pathogens. The minimum inhibitory concentration (MIC) values of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 were 0.05 mL/mL and 0.025 mL/mL, respectively, and the minimum bactericidal concentration (MBC) were both 0.2 mL/mL. It was observed by fluorescence microscope that the green fluorescence area of the two biofilms is greatly reduced after being treated with fermented beverage. Sensory analysis results show that the average scores of fermented beverage in color, appearance and taste were increased. The overall impression and flavor were decreased.

Conclusion

These results demonstrated that strawberry fermented beverage has potential benefits such as an antioxidant, antibacterial, and anti-biofilm formation, providing the potential for the fermented beverage to become promising candidates for natural antioxidants, antibacterial agents and anti-biofilm agents.

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.

Microencapsulation of Lactobacillus rhamnosus ATCC 7469 by spray drying using maltodextrin, whey protein concentrate and trehalose

This study aimed to microencapsulate Lactobacillus rhamnosus (L. rhamnosus) ATCC 7469 with whey protein concentrate (WPC), maltodextrin and trehalose by spray drying and to assess the impact of microencapsulation on cell viability and the properties of the dried powders. Spray-drying conditions, including inlet air temperature, air flow rate and feed pump, were fixed as independent variables, while probiotic survival, moisture content, water activity and effective yield were established as dependent variables. The survival of encapsulated L. rhamnosus by spray drying was optimized with response surface methodology, and the stability of the powder was assessed. The optimum spray-drying conditions were an inlet air temperature, air flow rate and feed pump rate of 169 °C, 33 m³·h^-1 and 16 mL·min^-1, respectively, survival of 70%, air aspiration of 84% and outlet air temperature of 52 °C, achieving an overall desirability of 0.96. The physicochemical and structural characteristics of the produced powder were acceptable for application with regard to residual water content, hygroscopicity, water activity, and particle size. The results indicated that a protein-trehalose-maltodextrin mixture is a good wall material to encapsulate L. rhamnosus, showing important thermal protection during the drying process and increasing survival. However, a decrease in this capacity is observed at an air outlet temperature of approximately 101 °C. The possible effects of the wall materials and the drying conditions on survival are also discussed.

Fortification of set yogurt with passion fruit juice: Effects on fermentation kinetics, physicochemical properties, and functionality

With the purpose of developing an alternative set yogurt with high consumer acceptability, passion fruit juice, at levels that varied from 0 to 10%, was incorporated into set yogurt, and the effects on the fermentation kinetics, physicochemical properties, and functionality of set yogurt were evaluated. The results showed that the addition of passion fruit juice was simultaneously propitious for milk acidification in earlier fermentation stages and reduced the fermentation rate at later stages of fermentation. The phenolic compounds and pectin in passion fruit juice interacted with caseins to form soluble complexes, enhancing the gel strength of set yogurts by 7.5%. The aroma and flavor of the set yogurt was improved as well. However, with the addition of 10% passion fruit juice, the gel structure was destroyed, and the quality of the set yogurt was very degraded. More importantly, the addition of passion fruit juice increased the polyphenol content and significantly enhanced the antioxidant activity of the set yogurt. This investigation demonstrated the feasibility of fabricating passion fruit juice-enriched set yogurt and its superior quality compared with the corresponding normal product.

Nanoencapsulation of Saccharomycopsis fibuligera VIT-MN04 using electrospinning technique for easy gastrointestinal transit

In this study, probiotic yeast Saccharomycopsis fibuligera (S. fibuligera) VIT-MN04 was encapsulated with wheat bran fibre (WBF) and exopolysaccharide (EPS) along with 5% polyvinylpyrrolidone (PVP) using electrospinning technique for easy gastrointestinal transit (GIT). The electrospinning materials viz. WBF (10%), EPS (15%), PVP (5%) and electrospinning parameters viz. applied voltage (10 kV) and tip to collector distance (15 cm) were optimised using response surface methodology to produce fine nanofibres to achieve maximum encapsulation efficiency (100%) and GIT tolerance (97%). The probiotic yeast was successfully encapsulated in nanofibre and investigated for potential properties. The survival of encapsulated S. fibuligera VIT-MN04 was increased compared to the free cells during in vitro digestion. In addition, encapsulated yeast cells retained their viability during storage at 4°C for 56 days. The nanofibres were characterised using scanning electron microscopy, atomic force microscopy, X-ray diffraction, thermogravimetric analysis, zeta potential analysis and Fourier transform infrared spectroscopy followed by gas chromatography-mass spectrometry and nuclear magnetic resonance analysis. This work provides an efficient approach for encapsulation of probiotic yeast with the nanofibres which can also broaden the application of the prebiotic like WBF providing an idea for the efficient preparation of functional synbiotic supplements in the food industry.