Food Matrix Design for Effective Lactic Acid Bacteria Delivery

Dark chocolate: delivery medium for probiotic Bifidobacterium breve NCIM 5671

Bifidobacteria are widely acclaimed probiotic bacteria, however, the fragile nature of the bacteria has rendered its delivery through food products a challenge. The aim of the present study was to develop probiotic dark chocolate by incorporating Bifidobacterium breve NCIM5671. The probiotic chocolate was prepared by adding B. breve to dark chocolate at the final tempering stage. The chocolate was evaluated for the viability of B. breve upon preparation and during storage period of 90 days. The effect of addition of B. breve on physiological parameters of chocolate such as color, texture, rheology, melting profile, and sensory profile was also determined. The probiotic chocolate developed retained viability of B. breve (9 log CFU/g) for a period of 90 days. No significant differences were observed in physiological parameters of probiotic chocolate compared to control chocolate. Overall the probiotic dark chocolate was found to be a suitable matrix for delivery of B. breve NCIM5671.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-05958-6.

Recent Advances in the Understanding of Stress Resistance Mechanisms in Probiotics: Relevance for the Design of Functional Food Systems

In recent years, more and more scientific community, food producers, and food industry show increased interest in functional foods containing probiotics, which is a big challenge. The consumption of probiotics in the context of a balanced diet through the consumption of functional foods or through the intake of pharmaceutical preparations has proven to contribute to the improvement of human health, even contributing to the prevention of diseases. In order for probiotics to be considered suitable for consumption, they must contain a minimum concentration of viable cells, namely, at least 107 colony forming units of beneficial microbes per gram. Ensuring the viability of bacterial cells until the moment of consumption is the overriding priority of functional probiotic food manufacturers. Probiotic bacteria are subject to stress conditions not only during food manufacturing but also during gastrointestinal passage, which limit or even compromise their functionality. This paper first examines all the stressful conditions faced by probiotic cells in their production stages and related to the conditions present in the bioreactor fermentation and drying processes as well as factors related to the food matrix and storage. The stress situations faced by probiotic microorganisms during the gastrointestinal transit especially during stomach and intestinal residence are also analyzed. In order to understand the adaptation mechanisms of probiotic bacteria to gastrointestinal stress, intrinsic and adaptive mechanisms identified in probiotic strains in response to acid stress and to bile and bile acid stress are analyzed. In addition, improvement strategies for multiple stress tolerance of lactic acid bacteria through directions dealing with stress, accumulation of metabolites, use of protectants, and regulation of technological parameters are examined. Finally, the definition of postbiotics, inanimate microorganisms and/or their components conferring health benefits, is also introduced. Postbiotics include cell lysates, enzymes, and cell wall fragments derived from probiotic bacteria and may represent an alternative to the use of probiotics, when they do not tolerate stressful conditions.

Drying of probiotics to enhance the viability during preparation, storage, food application, and digestion: A review

Functional food products containing viable probiotics have become increasingly popular and demand for probiotic ingredients that maintain viability and stability during processing, storage, and gastrointestinal digestions. This has resulted in heightened research and development of powdered probiotic ingredients. The aim of this review is to overview the development of dried probiotics from upstream identification to downstream applications in food. Free probiotic bacteria are susceptible to various environmental stresses during food processing, storage, and after ingestion, necessitating additional materials and processes to preserve their activity for delivery to the colon. Various classic and emerging thermal and nonthermal drying technologies are discussed for their efficiency in preparing dehydrated probiotics, and strategies for enhancing probiotic survival after dehydration are highlighted. Both the formulation and drying technology can influence the microbiological and physical properties of powdered probiotics that are to be characterized comprehensively with various techniques. Furthermore, quality control during probiotic manufacturing and strategies of incorporating powdered probiotics into liquid and solid food products are discussed. As emerging technologies, structure-design principles to encapsulate probiotics in engineered structures and protective materials with improved survivability are highlighted. Overall, this review provides insights into formulations and drying technologies required to supplement viable and stable probiotics into functional foods, ensuring the retention of their health benefits upon consumption.

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.

An In Vitro Study of the Impacts of Sweet Potato Chips with Potentially Probiotic Levilactobacillus brevis and Lactiplantibacillus plantarum on Human Intestinal Microbiota : Impacts of potato chips with probiotics on intestinal microbiota

This study formulated sweet potato chips with powdered potentially probiotic Levilactobacillus brevis (SPLB) and Lactiplantibacillus plantarum (SPLP) and evaluated their impacts on human intestinal microbiota during 48 h of in vitro colonic fermentation. L. brevis and L. plantarum kept high viable cell counts (> 6 log CFU/g) on sweet potato chips after freeze-drying and during 60 days of storage. SPLB and SPLP had satisfactory quality parameters during 60 days of storage. SPLB and SPLP increased the relative abundance of Lactobacillus ssp./Enterococcus spp. (3.84-10.22%) and Bifidobacterium spp. (3.25-12.45%) and decreased the relative abundance of Bacteroides spp./Prevotella spp. (8.56-2.16%), Clostridium histolyticum (8.23-2.33%), and Eubacterium rectale/Clostridium coccoides (8.07-1.33%) during 48 h of in vitro colonic fermentation. SPLB and SPLP achieved high positive prebiotic indexes (> 8.24), decreased pH values and sugar contents, and increased lactic acid and short-chain fatty acid production, proving selective stimulatory effects on beneficial bacterial groups forming the intestinal microbiota. The results showed that SPLB and SPLP have good stability and high viable cell counts of L. brevis and L. plantarum when stored under room temperature and caused positive impacts on human intestinal microbiota, making them potentially probiotic non-dairy snack options.

Development of Non-Dairy Synbiotic Fruit Beverage Using Adansonia digatata (baobab) Fruit Pulp as Prebiotic

Probiotics improve gut health; however, their intake through diet is mainly in the form of dairy products, which represents a challenge to lactose-intolerant individuals and vegetarians. This study aimed to determine the prebiotic potential of baobab and to evaluate the potential of using fermented baobab-based beverages as functional foods. The prebiotic content of baobab fruit pulp was determined. Lactic acid bacteria (LAB) were isolated from raw milk samples, identified through phenotypic and molecular methods, and evaluated for their probiotic potential. Three potential non-dairy synbiotic functional beverages using baobab fruit pulp fermented with potential probiotic Limosilactobacillus fermentum and mixed with milk, water, and apple juice separately were produced. The growth and survival of probiotic L. fermentum in the beverages at room (25 °C) and refrigeration (4 °C) temperatures for 3 weeks were determined. Baobab fruit pulp contained phytochemicals, vitamins, fatty acids, inulin, and fructooligosaccharides. Sequence alignment of the LAB isolates identified homologous sequences of Lacticaseibacillus casei, Limosilactobacillus fermentum, Lactiplantibacillus plantarum, Lentilactobacillus buchneri, and Lactiplantibacillus pentosus with 97.2–98.5% similarity. All the lactic acid bacteria did not produce DNAse and gelatinase enzymes, exhibited antagonistic activity against test pathogenic organisms, and demonstrated tolerance to bile salt, simulated gastric juice, and acid. The viability of L. fermentum increased from an initial inoculum size of 106–108 CFU/mL in the baobab-based beverages and remained constant at 108 CFU/mL both at room and refrigeration temperatures. However, after three weeks, the viability of L. fermentum in the synbiotic beverages reduced to 107 CFU/mL. Refrigerated synbiotic beverages had more viable L. fermentum cells (8.04–8log10 CFU/mL) than those stored at room temperatures (7.95–7.7log10 CFU/mL) after three weeks of storage. This study has shown that baobab fruit pulp has prebiotic potential and can be used in the production of a non-dairy functional beverage.

Comparison Between Different Delivery Vehicles for the Probiotic Bifidobacterium animalis subsp. lactis HN019 on Experimental Periodontitis in Rats

This study aimed to assess the effects of the probiotic (PROB) Bifidobacterium animalis subsp. lactis HN019 in two different delivery vehicles in experimental periodontitis (EP), including the gene expression for IL-10, IFN-γ, and FOXP3. In total, 32 rats were assigned into groups (n=8): C (control), EP, EP-PROB/Water, and EP-PROB/Milk. The probiotic was administered for 4 weeks, from baseline to euthanasia. Periodontitis was induced by ligatures 14 days after baseline. Data were statistically analyzed (p<0.05). Both probiotic groups presented decreased alveolar bone loss and increased interproximal attachment level than group EP. Also, these parameters were significantly improved in the Milk group when compared with the Water group. EP-PROB/Milk showed higher gene expression for IL-10 and lower for FOXP3 in relation to EP-PROB/Water and EP groups. The use of milk was able to potentiate the protective effects of B. lactis HN019 in rats under EP.

Soymilk-fermented with Lactobacillus delbrueckii subsp. delbrueckii TUA4408L improves immune-health in pigs

Lactobacillus delbrueckii subsp. delbrueckii TUA4408L has the ability to grow and ferment soymilk and is able to modulate the innate immune response of intestinal epithelial cells in vitro. These two properties prompt us to evaluate whether the soymilk fermented with the TUA4408L strain can induce beneficial immunomodulatory effects in vivo. For this purpose, pigs were selected as a preclinical model. The studies performed here demonstrated that the L. delbrueckii subsp. delbrueckii TUA4408L-fermented soymilk (TUA4408L FSM) reduced blood markers of inflammation and differentially regulated the expression of inflammatory and regulatory cytokines in the intestinal mucosa. These immunological changes induced by the TUA4408L FSM were associated to an enhanced resistance to pathogenic Escherichia coli and an improved grow performance and meat quality of pigs. The experiments and analysis in our study indicate that the immunobiotic TUA4408L FSM could be an interesting non-dairy functional food to beneficially modulate the intestinal immune system, improve protection against pathogens and reduce inflammatory damage. The preclinical study carried out here in pigs could have a better correlation in humans, compared to a rodent model. However, the clinical relevance of these findings still needs to be confirmed by further research, for example, in controlled human challenge studies.

Selection of Lactic Acid Bacteria with In Vitro Probiotic-Related Characteristics from the Cactus Pilosocereus gounellei (A. Weber ex. K. Schum.) Bly. ex Rowl

Pilosocereus gounellei (A. Weber ex. K. Schum.) Bly. ex Rowl., popularly known as xique-xique, is a cactus from the Caatinga biome, which is rich in bioactive compounds but has not been previously studied as a source of lactic acid bacteria (LAB) with probiotic aptitudes. This study aimed to identify, characterize, and select LAB isolates with in vitro probiotic-related characteristics from xique-xique cladodes and fruit. Isolates with the most promising probiotic-related characteristics were evaluated regarding their in vitro technological properties and capability of surviving in chestnut milk, whey protein drink, and mate tea with mint during 21 days of refrigeration storage. Seventeen recovered isolates had typical characteristics of LAB. Six out of these seventeen LAB isolates passed the safety tests and were included in experiments to evaluate the in vitro probiotic-related characteristics. Based on the results of a principal component analysis, the isolates 69, 82, 98, and 108 had the best performances in experiments to evaluate the probiotic-related characteristics. In addition to showing good technological properties, the four selected LAB isolates had high viable counts (>7.3 log cfu/mL) and high sizes of physiologically active cell subpopulations in chestnut milk, whey protein drink, and mate tea during refrigeration storage. These four isolates were identified by 16S-rRNA sequencing as being Lacticaseibacillus paracasei or Lacticaseibacillus casei. The results indicate xique-xique as a source of potentially probiotic LAB isolates.

Antioxidants Bioaccessibility and Lactobacillus salivarius (CECT 4063) Survival Following the In Vitro Digestion of Vacuum Impregnated Apple Slices: Effect of the Drying Technique, the Addition of Trehalose, and High-Pressure Homogenization

To benefit the health of consumers, bioactive compounds must reach an adequate concentration at the end of the digestive process. This involves both an effective release from the food matrix where they are contained and a high resistance to exposure to gastrointestinal conditions. Accordingly, this study evaluates the impact of trehalose addition (10% w/w) and homogenization (100 MPa), together with the structural changes induced in vacuum impregnated apple slices (VI) by air-drying (AD) and freeze-drying (FD), on Lactobacillus salivarius spp. salivarius (CECT 4063) survival and the bioaccessibility of antioxidants during in vitro digestion. Vacuum impregnated apple slices conferred maximum protection to the lactobacillus strain during its passage through the gastrointestinal tract, whereas drying with air reduced the final content of the living cells to values below 10 cfu/g. The bioaccessibility of antioxidants also reached the highest values in the VI samples, in which the release of both the total phenols and total flavonoids to the liquid phase increased with in vitro digestion. The addition of trehalose and homogenization at 100 MPa increased the total bioaccessibility of antioxidants in FD and AD apples and the total bioaccessibility of flavonoids in the VI samples. Homogenizing at 100 MPa also increased the survival of L. salivarius during in vitro digestion in FD samples.

In vitro gastrointestinal resistance of Lactobacillus acidophilus in some dairy products

In this study, different dairy products such as ice cream, yoghurt, white pickled cheese, and fermented acidophilus milk were manufactured by using either Lactobacillus acidophilus DSM 20,079 or Lactobacillus acidophilus NCFM. The counts of L. acidophilus in the samples on days 1, 15, and 30 of the storage were determined. Additionally, the samples contained L. acidophilus were passed through a dynamic gastrointestinal model designed in laboratory conditions to compare the protective effect of different dairy products on viability of L. acidophilus against stress factors of the gastrointestinal model. The counts of L. acidophilus NCFM and L. acidophilus DSM 20,079 in the samples decreased by between 0.04 and 0.37 log units and by between 0.11 and 0.27 log units, respectively, within 30 days of storage. During the passage through the gastrointestinal model, the highest percentage reduction in the counts of L. acidophilus was determined in yoghurt followed by fermented acidophilus milk, white pickled cheese, and ice cream, respectively. The reduction in the counts of L. acidophilus in the samples during the passage through the model increased with extension of storage time. The results of this study showed that the reduction in the counts L. acidophilus in the samples during the passage through the model was influenced significantly by the matrix of the dairy product and storage period.

Stress Effect of Food Matrices on Viability of Probiotic Cells during Model Digestion

The aim of this study was to evaluate the influence of model (alcohol, sugar, salt, protein and acid) and real foods and beverages on the viability of probiotics during incubation and artificial digestion. Viability of monocultures Lactobacillus acidophilus CCM4833 and Bifidobacterium breve CCM7825T, and a commercial mixture of 9 probiotic bacterial strains, was tested by cultivation assay and flow cytometry. In model foods, the best viability was determined in the presence of 0.2 g/L glucose, 10% albumin and 10% ethanol. As the most suitable real food for probiotic survival, complex protein and carbohydrate substrates were found, such as beef broth, potato salad with pork, chicken with rice, chocolate spread, porridge and yoghurt. The best liquid was milk and meat broth, followed by Coca-Cola, beer and coffee. Viability of probiotics was higher when consumed with meals than with beverages only. Addition of prebiotics increased the viability of probiotics, especially in presence of instant and fast foods. Generally, the highest viability of probiotics during artificial digestion was observed in mixed culture in the presence of protein, sugar and fat, or their combination. The increase of cell viability observed in such foods during model digestion may further contribute to the positive effect of probiotics on human health.

Development of Probiotic Almond Beverage Using Lacticaseibacillus rhamnosus GR-1 Fortified with Short-Chain and Long-Chain Inulin Fibre

Plant-based beverages are growing in popularity due to the rise of vegetarianism and other health trends. A probiotic almond beverage that combines the properties of almonds, inulin, and Lacticaseibacillusrhamnosus GR-1 may meet the demand for a non-dairy health-promoting food. The purpose of this study was to investigate the viability of L. rhamnosus GR-1 and pH in five fermented almond beverage samples, supplemented with either 2% or 5% (w/v) short-chain or long-chain inulin over 9 h of fermentation and 30 days of refrigerated storage. All almond beverage samples achieved a mean viable count of at least 107 CFU/mL during 9h of fermentation and 30 days of refrigerated storage. The probiotic almond beverage supplemented with 2% (w/v) short-chain inulin had a significantly higher mean microbial count (p = 0.048) and lower pH (p < 0.001) throughout fermentation, while the control and the long-chain inulin treatments had the lowest viable counts and acidity, respectively. This study shows that the addition of short-chain and long-chain inulin had no adverse effects on the viability of L. rhamnosus GR-1. Therefore, the probiotic almond beverage has the potential to be a valid alternative to dairy-based probiotic products.

A SH3_5 Cell Anchoring Domain for Non-recombinant Surface Display on Lactic Acid Bacteria

Lactic acid bacteria (LAB) are a group of gut commensals increasingly recognized for their potential to deliver bioactive molecules in vivo. The delivery of therapeutic proteins, in particular, can be achieved by anchoring them to the bacterial surface, and various anchoring domains have been described for this application. Here, we investigated a new cell anchoring domain (CAD4a) isolated from a Lactobacillus protein, containing repeats of a SH3_5 motif that binds non-covalently to peptidoglycan in the LAB cell wall. Using a fluorescent reporter, we showed that C-terminal CAD4a bound Lactobacillus fermentum selectively out of a panel of LAB strains, and cell anchoring was uniform across the cell surface. Conditions affecting CAD4a anchoring were studied, including temperature, pH, salt concentration, and bacterial growth phase. Quantitative analysis showed that CAD4a allowed display of 10⁵ molecules of monomeric protein per cell. We demonstrated the surface display of a functional protein with superoxide dismutase (SOD), an antioxidant enzyme potentially useful for treating gut inflammation. SOD displayed on cells could be protected from gastric digestion using a polymer matrix. Taken together, our results show the feasibility of using CAD4a as a novel cell anchor for protein surface display on LAB.

A Fast, Efficient and Easy to Implement Method to Purify Bacterial Pili From Lacticaseibacillus rhamnosus GG Based on Multimodal Chromatography

Pili are polymeric proteins located at the cell surface of bacteria. These filamentous proteins play a pivotal role in bacterial adhesion with the surrounding environment. They are found both in Gram-negative and Gram-positive bacteria but differ in their structural organization. Purifying these high molecular weight proteins is challenging and has certainly slowed down their characterization. Here, we propose a chromatography-based protocol, mainly relying on multimodal chromatography (core bead technology using Capto Core 700 resin), to purify sortase-dependent SpaCBA pili from the probiotic strain Lacticaseibacillus rhamnosus GG (LGG). Contrary to previously published methods, this purification protocol does not require specific antibodies nor complex laboratory equipment, including for the multimodal chromatography step, and provides high degree of protein purity. No other proteins were detectable by SDS-PAGE and the 260/280 nm ratio (∼0.6) of the UV spectrum confirmed the absence of any other co-purified macromolecules. One can obtain ∼50 μg of purified pili, starting from 1 L culture at OD_600nm ≈ 1, in 2–3 working days. This simple protocol could be useful to numerous laboratories to purify pili from LGG easily. Therefore, the present work should boost specific studies dedicated to LGG SpaCBA pili and the characterization of the interactions occurring with their protein partners at the molecular level. Moreover, this straightforward purification process might be extended to the purification of sortase-dependant pili from other Gram-positive bacteria.

Characterization of adhesion between Limosilactobacillus reuteri and milk phospholipids by density gradient and gene expression

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The interaction between lactic acid bacteria and milk phospholipids can be semi-quantified

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Binding and interaction between milk phospholipids and LAB is mediated by gene modulation

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Two of three genes for surface adhesion corresponded directly with binding results

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This method identifies LAB that adhere tightly to the intestinal membranes

The benefits of fermented dairy products, in particular the presence of lactic acid bacteria (LAB) and milk phospholipids (MPL), seem to correlate with positive effects on human health. We hypothesize that one aspect of this benefit is the adhesion of LAB to the milk fat globule membrane via the interaction of LAB and MPL. Our first objective was to present a method to characterize and quantify such adhesion and investigate its association with a physical test. Our second objective was to further analyze the mechanism of interaction by analyzing expression of 3 previously reported surface binding-promoting genes (MapA, Cnb, and CmbA). We categorized adhesion between MPL and LAB by observing the distribution of MPL in corresponding bacterial cultures. Our working hypothesis was that any interaction or adhesion between these 2 components would yield differences in the distribution of MPL. Out of 122 LAB tested, 27% showed what could be characterized as adhesion; 38% of these strains were Limosilactobacillus reuteri. Further characterization of adhesion was carried out using an reverse transcription quantitative-PCR experiment, which demonstrated that the relative expression level of CmbA was positively associated with that adhesion. In addition, supplementation of MPL caused overexpression of MapA and Cnb in L. reuteri OSU-PECh-37A and OSU-PECh-48. This study indicated strain-specific adhesion between MPL and LAB and suggested that CmbA, which encodes a surface protein, is a potential factor involved in that adhesion. A better understanding of interactions between MPL and LAB may contribute to the design of new functional products and improve the delivery of these bioactive ingredients to their target site of action.

Shaving and breaking bacterial chains with a viscous flow

Some food and ferment manufacturing steps such as spray-drying result in the application of viscous stresses to bacteria. This study explores how a viscous flow impacts both bacterial adhesion functionality and bacterial cell organization using a combined experimental and modeling approach. As a model organism we study Lactobacillus rhamnosus GG (LGG) "wild type" (WT), known to feature strong adhesive affinities towards beta-lactoglobulin thanks to pili produced by the bacteria on cell surfaces, along with three cell-surface mutant strains. Applying repeated flows with high shear-rates reduces bacterial adhesive abilities up to 20% for LGG WT. Bacterial chains are also broken by this process, into 2-cell chains at low industrial shear rates, and into single cells at very high shear rates. To rationalize the experimental observations we study numerically and analytically the Stokes equations describing viscous fluid flow around a chain of elastically connected spheroidal cell bodies. In this model setting we examine qualitatively the relationship between surface traction (force per unit area), a proxy for pili removal rate, and bacterial chain length (number of cells). Longer chains result in higher maximal surface tractions, particularly at the chain extremities, while inner cells enjoy a small protection from surface tractions due to hydrodynamic interactions with their neighbors. Chain rupture therefore may act as a mechanism to preserve surface adhesive functionality in bacteria.

Microbial and Sensory Analysis of Soy and Cow Milk-Based Yogurt as a Probiotic Matrix for Lactobacillus rhamnosus GR-1

Plant-based milk alternatives represent a growing sector of the functional food industry due to consumer demand for more nutritious and sustainable options. Soymilk is abundant in fibre, phytosterols, and isoflavones. In contrast, cow milk has a high cholesterol and caloric content, superior organoleptic characteristics, and a well-established probiotic delivery matrix. Supplementing cow milk with soymilk to produce probiotic yogurt may enhance the nutritional value, sensory profile, and probiotic delivery capacity of the final product. In order to investigate the probiotic potential and sensory appeal of this blend, four yogurt mixtures were prepared by incorporating 0% (T1), 25% (T2), 50% (T3), or 75% (T4) soymilk in cow milk. The viability of Lactobacillus rhamnosus GR-1 and pH were evaluated during fermentation (6 h) and refrigerated storage (30 days). Additionally, consumer acceptability was determined through a sensory evaluation. L. rhamnosus GR-1 reached viable counts of 108 colony forming units (CFU)/mL in all treatments. Sensory panellists provided higher hedonic scores to T1 for appearance and texture compared to T2–T4, but flavour and overall acceptability ratings amongst T1–T4 were comparable. These results serve as an indication for the successful fortification of cow and soymilk yogurt mixtures with L. rhamnosus GR-1.

Tailoring functional beverages from fruits and vegetables for specific disease conditions-are we there yet?

On-the-go beverages that may deliver health, increase stamina, reduce stress and provide longevity have captivated consumers and catapulted the food industry into the era of functional food and beverages. The industry initially responded with rapid growth. However, with time product diversification has become somewhat compromised, since most products contain the same bioactive components. Advancement in product technology has to be backed with research. Mere fortification of tea, juices and water, without any scientific evaluation of their functionality, has to be discouraged. Fruits and vegetable juices are excellent matrices for delivery of physiologically active component. Science backed designing will get us closer to tailoring fruits and vegetable juices into 'smart' beverages. As a case study two fruit-based products, probiotic and fruit wines (non-grape) have been considered here. This review explores the possibility of what more may be done to take the fruit and vegetable beverages to next step.

Adhesion and anti-inflammatory potential of Lactobacillus rhamnosus GG in a sea buckthorn based beverage matrix

A seabuckthorn based beverage matrix retains the functionality of L. rhamnosus GG and exhibits enhanced anti-inflammatory effects against LPS-induced inflammation in zebrafish.

Postprandial glycemia in healthy subjects: Which probiotic dairy food is more adequate?

The consumption of probiotic-enriched dairy products has been associated with many health benefits, including anti-hyperglycemic activity. The effect on health is dependent on the type of probiotic culture used and the dairy product consumed. This study evaluated the effect of different probiotic-enriched dairy matrices (Minas Frescal cheese, Prato cheese, and whey dairy beverage) containing Lactobacillus casei on in vitro and in vivo anti-hyperglycemic activity. For this purpose, in vitro anti-hyperglycemic activity was determined by the inhibition of α-glucosidase and α-amylase activities, and a human study was performed with healthy individuals (n = 15, consumption of bread as a control; bread + Minas Frescal cheese; bread + Prato cheese; bread + dairy beverage) to assess the effects of different probiotic foods on postprandial glycemia. In vitro data showed that Prato cheese presented the highest lipid (36.9 g/100 g) and protein (26.5 g/100 g) contents as well as the highest α-amylase (60.7%) and α-glucosidase (52.6%) inhibition. The consumption of Prato cheese resulted in a lesser increase in blood glucose level (13 mg/dL) compared with the consumption of bread alone (19 mg/dL), Minas Frescal cheese (20 mg/dL), and whey dairy beverage (30 mg/dL), with glycemic indices similar to that observed for the control. The present results demonstrated a good correlation between in vitro and in vivo data, in which the type of dairy matrix affects the anti-hyperglycemic activity. It is concluded that the consumption of probiotic Prato cheese can contribute to the reduction of postprandial glycemia in healthy individuals.

Adhesive Interactions Between Lactic Acid Bacteria and β-Lactoglobulin: Specificity and Impact on Bacterial Location in Whey Protein Isolate

In the last decade, there has been an increasing interest in the potential health effects associated with the consumption of lactic acid bacteria (LAB) in foods. Some of these bacteria such as Lactobacillus rhamnosus GG (LGG) are known to adhere to milk components, which may impact their distribution and protection within dairy matrices and therefore is likely to modulate the efficiency of their delivery. However, the adhesive behavior of most LAB, as well as its effect on food structuration and on the final bacterial distribution within the food matrix remain very poorly studied. Using a recently developed high-throughput approach, we have screened a collection of 73 LAB strains for their adhesive behavior toward the major whey protein β-lactoglobulin. Adhesion was then studied by genomics in relation to common bacterial surface characteristics such as pili and adhesion-related domain containing proteins. Representative adhesive and non-adhesive strains have been studied in further depth through biophysical measurement using atomic force microscopy (AFM) and a relation with bacterial distribution in whey protein isolate (WPI) solution has been established. AFM measurements have revealed that bacterial adhesion to β-lactoglobulin is highly specific and cannot be predicted accurately using only genomic information. Non-adhesive strains were found to remain homogeneously distributed in solution whereas adhesive strains gathered in flocs. These findings show that several LAB strains are able to adhere to β-lactoglobulin, whereas this had only been previously observed on LGG. We also show that these adhesive interactions present similar characteristics and are likely to impact bacterial location and distribution in dairy matrices containing β-lactoglobulin. This may help with designing more efficient dairy food matrices for optimized LAB delivery.