A comprehensive review on the utilization of biopolymer hydrogels to encapsulate and protect probiotics in foods.

Probiotics must survive in foods and passage through the human mouth, stomach, and small intestine to reach the colon in a viable state and exhibit their beneficial health effects. Probiotic viability can be improved by encapsulating them inside hydrogel-based delivery systems. These systems typically comprise a 3D network of cross-linked polymers that retain large amounts of water within their pores. This study discussed the stability of probiotics and morphology of hydrogel beads after encapsulation, encapsulation efficiency, utilization of natural polymers, and encapsulation mechanisms. Examples of the application of these hydrogel-based delivery systems are then given. These studies show that encapsulation of probiotics in hydrogels can improve their viability, provide favorable conditions in the food matrix, and control their release for efficient colonization in the large intestine. Finally, we highlight areas where future research is required, such as the large-scale production of encapsulated probiotics and the in vivo testing of their efficacy using animal and human studies.

In situ produced exopolysaccharides by Bacillus coagulansIBRC-M 10807 and its effects on properties of whole wheat sourdough.

This study aimed to investigate in situ exopolysaccharides (EPSs) production by Bacillus coagulans IBRC-M 10807 under different fermentation conditions to improve the technical-functional properties of whole wheat flour sourdough and obtain high-quality products. For this purpose, the effectiveness of four efficient factors including B. coagulans (8 Log CFU/g), FOS (0%, 2.5%, and 5% based on flour weight), fermentation temperature (30, 35, and 40°C), and fermentation time (12, 18, and 24 h) was investigated on the production of functional sourdough. Our work focused on optimizing probiotic sourdough by investigating probiotic viability, pH, total titratable acidity, antioxidant properties, and EPS measurement. The first optimal formulation for maximized production of the in situ EPSs by the numerical optimization included FOS 0%, B. coagulans IBRC-M 10807 8 Log CFU/g, fermentation temperature of 30°C, and fermentation time of 12 h. In this case, EPSs was 59.28 mg/g and probiotic was 10.99 Log CFU/g. The second optimal formula by considering the highest viability of probiotic together with EPS production was determined as FOS 4.71%, B. coagulans IBRC-M 10807, 8 Log CFU/g, fermentation temperature of 30°C, and fermentation time of 20 h. The predicted amount of the EPSs and probiotic viability via the second formulation were 54.4 mg/g and 11.18 Log CFU/g, respectively. Analyses of optimal sourdough using FTIR, SEM, and DSC revealed that FOS and probiotics significantly reduced the enthalpy of amylopectin retrogradation and delayed it compared to other samples. Therefore, improving the final product's technological capabilities and shelf life can be credited with potential benefits.

Development and properties of functional yoghurt enriched with postbiotic produced by yoghurt cultures using cheese whey and skim milk.

This study aimed to examine the effects of supplementation of postbiotics derived from Streptococcus thermophilus (ST) and Lactobacillus delbrueckii subsp. bulgaricus (LB) in cheese whey (CW) and skim milk (SM) on antioxidant activity, viability of yoghurt starters, and quality parameters of low-fat yoghurt during 22 days of storage. The LB-CW (L delbrueckii ssp. bulgaricus postbiotic-containing cheese whey) sample exhibited the highest antioxidant activity, with 18.71% inhibition (p > 0.05). This sample also showed the highest water holding capacity (77.93%; p < 0.05) and a trend toward receiving the most favorable sensory attributes (p > 0.05) compared to the other samples. The LB-CW and LB-SM yoghurt samples exhibited significantly higher body and texture scores compared to the ST-SM-fortified yoghurt (p < 0.05). However, there was no significant difference in the overall acceptability of the LB-SM and ST-SM yoghurt samples across both starters (p > 0.05). Such findings highlight the potential of postbiotics as functional ingredients to enhance the nutritional and sensory aspects of yoghurt, further contributing to its appeal as a health-promoting product.

Development of a colorimetric sensor based on nanofiber cellulose film modified with ninhydrin to measure the formalin index of fruit juice.

In this research, a color sensor based on nanofiber cellulose film modified with ninhydrin was designed to measure amino acids and formalin index in fruit juice. For this purpose, three types of cellulose films with porosity of 5, 30 and 125 µm were used. These films were treated with standard solution of ninhydrin. The characteristics of modified films were investigated using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray Diffraction (XRD) tests. The color factors of the sensors (a and b) changed in the presence of amino acids and juice with different levels of formalin index. Therefore, the modified films with ninhydrin as a colorimetric sensor were calibrated using 7 types of amino acids and based on the formalin index of 4 types of juice. Then the sensors were used to measure the formalin index in 4 types of juice. The results showed that the sensors have relative selectivity towards methionine amino acid. The formalin index values calculated in the juices by the sensor were compared with the titration method as a reference method. All three types of sensors were able to detect formalin index. The results of the sensor performance verification showed that the sensors can measure formalin index in different juices with 95-98 % accuracy. These sensors showed fast sensitivity and selectivity to the amino acids in juice, also these sensors are safe and the measurement method is fast and simple.

Opopanax gum and essential oil-based antimicrobial film reinforced with bismuth oxide nanoparticles: Production, characterization, and application in the storage of quail fillets.

The aim of this study was to the production of an active film based on Prangos ferulacea root gum, using its leaf's essential oil (PFEO) (0-3 %) and bismuth oxide nanoparticles (Bi2O3NPs) (0-3 %). Then, the developed film was used for packaging of quail fillet. Response surface methodology was used to evaluate the effect of PFEO and Bi2O3NPs on films' properties. Optimum formulation, including 1.5 % PFEO and 1 % Bi2O3NPs, was achieved based on numerical optimization. The optimum film was produced and compared with the control film (based on Prangos ferulacea root gum, without PFEO and Bi2O3NPs). According to the results, adding PFEO and Bi2O3NPs to the film formulation increased the thickness and antioxidant activity of the film and decreased moisture content, solubility, water vapor permeability, and whiteness index (p < 0.05). The optimum film indicated high antimicrobial effects on Escherichia coli and Staphylococcus aureus. The pH, TVBN, TBA values, coliform, and total bacterial counts of quail fillet packed with the optimum film were lower and sensorial scores were higher than the control samples during the storage(p < 0.05).

Application of Cheese Whey Containing Postbiotics of Lactobacillus acidophilus LA5 and Bifidobacterium animalis BB12 as a Preserving Liquid in High-Moisture Mozzarella.

High-moisture mozzarella cheese (HMMC) is a highly perishable cheese with a short shelf life. In this study, the effects of UF cheese whey containing postbiotics from Lactobacillus acidophilus LA-5 (P-LA-5), Bifidobacterium animalis BB-12 (P-BB-12), and their combination on the microbial (i.e., psychrophiles, mesophiles, lactic acid bacteria, and mold-yeast population) and sensory properties of HMMC were investigated. Postbiotics were prepared in a cheese whey model medium as a novel growth media and used as a preserving liquid in HMMC. The results demonstrate that postbiotics reduced the growth of all microorganisms (1.5-2 log CFU/g reduction) and P-LA5 and P-BB12 had the highest antibacterial performance on mesophiles and psychrophiles, respectively. Mold and yeast had the highest susceptibility to the postbiotics. Postbiotics showed a significant effect on maintaining the microbial quality of HMMC during storage, proposing postbiotics as a new preserving liquid for HMMC.

Effect of the molecular structure and mechanical properties of plant-based hydrogels in food systems to deliver probiotics: an updated review.

Probiotic products' economic value and market popularity have grown over time as more people discover their health advantages and adopt healthier lifestyles. There is a significant societal and cultural interest in these products known as foods or medicines. Products containing probiotics that claim to provide health advantages must maintain a "minimum therapeutic" level (107-106 CFU/g) of bacteria during their entire shelf lives. Since probiotic bacteria are susceptible to degradation and reduction by physical and chemical conditions (including acidity, natural antimicrobial agents, nutrient contents, redox potential, temperature, water activity, the existence of other bacteria, and sensitivity to metabolites), the most challenging problem for a food manufacturer is ensuring probiotic cells' survival and stability enhancement throughout the manufacturing stage. Currently, the use of plant-based hydrogels for improved and targeted probiotic delivery has gained substantial attention as a potential approach to overcoming the mentioned restrictions. To achieve the best possible results from hydrogels, whether used as a coating for encapsulated probiotics (with the goal of stomach protection) or as carriers for direct encapsulation of live microorganisms should be applied kind of procedures that ensure high bacterial survival during hydrogels application. This paper summarizes polysaccharides, proteins, and lipid-based hydrogels as carriers of encapsulated probiotics in delivery systems, reviews their structures, analyzes their advantages and disadvantages, studies their mechanical characteristics, and draws comparisons between them. The discussion then turns to how the criterion affects encapsulation, applications, and future possibilities.

A novel source of food hydrocolloids from Trigonella elliptica seeds: extraction of mucilage and comprehensive characterization.

BACKGROUND: In this study, the effects of seed weight (4, 8, and 12 g), extraction temperature (30, 60, and 90 °C), and pH (4, 7, and 10) on the yield of mucilage extraction from fenugreek seeds and its chemical properties were investigated using response-surface methodology. RESULTS: The optimum condition for mucilage extraction was a seed weight of 8.30 g, a temperature of 86.10 °C, and pH 6.90. The results showed that the dry weight of extracted mucilage increased with increase and decrease of extraction temperature and pH respectively at high seed weight. Increasing temperature and pH increased the extraction yield, and the effect was more considerable at low seed weight. The maximum carbohydrate content of mucilage was achieved at average levels of variables. The protein, flavonoid, and total phenolic contents of extracted mucilage increased with increasing temperature. Both flavonoid and total phenolic contents were maximum at neutral pH, but they were maximum at moderate and low levels of seed weight respectively. Maximum antioxidant activity was obtained at the highest extraction temperature, seed weight of 8 g, and neutral pH. The study of rheological properties indicated that extracted mucilage solution showed mainly elastic and shear-thinning behavior. CONCLUSION: The Fourier transform infrared spectra of extracted mucilage exhibited the existence of polysaccharides and protein chains in fenugreek seeds mucilage. The X-ray diffraction corroborated the presence of crystals in the mucilage structure. The proton nuclear magnetic resonance spectra confirmed the polysaccharides and protein composition of extracted mucilage. The maximum mucilage mass loss was observed at 190-350 °C using thermogravimetric analysis. © 2022 Society of Chemical Industry.

Rapid detection of apple juice concentrate adulteration with date concentrate, fructose and glucose syrup using HPLC-RID incorporated with chemometric tools.

The present study investigates the substitute of apple juice concentrate with some cheap sweeteners including glucose syrup, fructose syrup, and date concentrate, as the most common adulterants. For this purpose, pure and authenticated apple juice concentrate was individually adulterated with 10% to 50% of glucose syrup, fructose syrup, and date concentrate. High-performance liquid chromatography coupled with a refractive index detector (HPLC-RID) was applied to determine the carbohydrates profile of samples. The results of HPLC-RID were subjected to multivariate statistical analysis, namely principal component analysis (PCA) and linear discriminant analysis (LDA). The results showed that the glucose/fructose ratio and maltose content were the best indicators to detect adulteration of apple juice concentrate. A set of glucose, sorbitol, sucrose, maltose, and glucose/fructose ratio was used as a discriminating factor. Using this approach, adulteration of apple juice concentrate with cheaper sweeteners was detected at a limit of 10%, depending on the adulterant.

Microencapsulation of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis BB-12 in pectin and sodium alginate: A comparative study on viability, stability, and structure.

The present study aimed at examining whether the microencapsulation of Lactobacillus acidophilus LA-5 and Bifidobacterium animalis BB-12 inside hydrogels could prolong their survival in freeze-drying conditions, stored at 4℃ and in the gastrointestinal medium. Microencapsulation was performed by emulsion with a syringe, while sodium alginate and high methoxyl pectin were used as a carrier material. A relatively high efficiency of encapsulation was obtained (>92%). Z-Average and pdI in samples were not significant (p < .05). In different treatments, changes in the number of bacteria after freeze-drying, 30 days of storage, and gastrointestinal conditions, compared to each other, were significant (p < .05). However, the survival rate after a reduction during storage was higher than 106 cfu/g, indicating the suitability of the microencapsulation process. The surface of microcapsules observed by a scanning electron microscope (SEM) confirmed the success of encapsulation. Finally, a lower decrease in the count of microencapsulated was observed in comparison to the free cells.

Optimization of food-grade medium for co-production of bioactive substances by Lactobacillus acidophilus LA-5 for explaining pharmabiotic mechanisms of probiotic.

This study aimed to optimize the co-production of conjugated linoleic acid (CLA), exopolysaccharides (EPSs) and bacteriocins (BACs) by Lactobacillus acidophilus LA-5 in dairy food-grade by-product. The factorial design revealed that the significant factors were temperature, time, and yeast extract. Then the response surface methodology was used for optimization. At the optimal conditions the viable cell number, CLA, EPSs, and inhibition activity were 2.62 ± 0.49 × 108 CFU/mL, 51.46 ± 1.50 µg/mL, 348.24 ± 5.61 mg/mL and 12.46 ± 0.80 mm, respectively. FTIR, GC, TLC, and SDS page analysis revealed the functional groups of pharmabiotics. The FTIR, GC, TLC, and SDS page analysis showed that both CLA isomers (c-9, t-11, and t-10, c-12) produced. The FTIR, GC, TLC, and SDS page analysis indicated that produced EPSs were composed of glucose, mannose, galactose, xylose, and fructose. FTIR, GC, TLC, and SDS page used to report BACs molecular weight, which showed two fractions by molecular mass 35 and 63 kDa. Previously the ability of different probiotic bacteria investigated and optimized the production of CLA, EPSs, and BACs, but, there was no report on the co-producing capacity of these bioactive metabolites by probiotics. The present work was investigated to optimize the co-production of pharmabiotic metabolites by L. acidophilus LA-5, in supplemented cheese whey as a cultivation medium.

Optimization of bacterial cellulose production by Komagataeibacter xylinus PTCC 1734 in a low-cost medium using optimal combined design.

This study was aimed to optimize the production of bacterial cellulose (BC) by Komagataeibacter xylinus PTCC 1734 using mixture of date syrup and cheese whey as carbon sources as well as ascorbic acid as a supplementary agent and to characterize the properties of produced BC. The results showed the highest BC production on the 10th day. The 50:50 ratio of date syrup and cheese whey lead to the highest BC production. Three samples were selected in optimal cultivation conditions until the 10th day, with different ascorbic acid concentrations (0, 0.1 and 0.4%). SEM results showed no difference in the morphology of BC product in the optimal samples, where the average diameter of cellulose nanofibers produced was in the range of nanometer. The FTIR test results showed no difference in the chemical structure of cellulose product in different ascorbic acid concentrations. According to XRD and TGA analyses, the highest degree of BC crystallinity and thermal resistance was obtained at maximum ascorbic acid concentration (0.04%). Consequently, the 50:50 ratio of date syrup and cheese whey and 10th day of fermentation time were selected as the best conditions for BC production. Though ascorbic acid reduced production efficiency, it improved the physical properties of the BC product.

Use of bacterial cellulose film modified by polypyrrole/TiO2-Ag nanocomposite for detecting and measuring the growth of pathogenic bacteria.

The aim of this study was to use of bacterial cellulose/polypyrrole/TiO2-Ag (BC/PPy/TiO2-Ag) nanocomposite film to detect and measure the growth of 5 pathogenic bacteria. For this purpose, at first, 13 BC/PPy/TiO2-Ag films were fabricated, then bacterial suspensions were prepared according to McFarland standard. The results showed that by increasing the bacterial concentration, the electrical resistance of sensors was decreased and there was a relation between bacterial concentration and bacterial type with electrical resistance change of sensors. The obtained data showed that the sensitivity of the sensors was increased with increasing the concentration of polypyrrole and TiO2-Ag. FT-IR and SEM tests were performed to investigate the interaction between nanoparticles and determine the size of nanoparticles. The BC/PPy/TiO2-Ag biosensors are portable and the response time of these sensors is very short for target analysis. Therefore, these sensors have the potential to improve biological safety as diagnostic tools.

Numerical optimization of probiotic Ayran production based on whey containing transglutaminase and Aloe vera gel.

The purpose of this study was to optimize the functional properties of probiotic Ayran. Two-level fractional factorial design with four center points was used to investigate the effect of five independent variables including, reconstructed whey protein (70-90% of milk), salt (0.5-1 g/100 g), Aloe vera gel (0-30 g/100 g), transglutaminase enzyme (0-14 unit/100 g) and storage time (1-21 days). The viability of Lactobacillus acidophilus La-5 and other physicochemical properties such as pH, acidity, viscosity, sedimentation, and color were modeled and then optimized using desirability function method. Results showed that reconstructed whey protein and Aloe vera gel significantly affected the viability of L. acidophilus La-5 and other physicochemical properties (p < 0.05). The viability of L. acidophilus La-5 and viscosity decreased by increasing of whey protein percentage from 70 to 90. Maximum L. acidophilus La-5 count was observed in samples with a minimum level of whey protein and maximum level of Aloe vera gel. Milk replacement with whey protein up to 90% caused to decrease acidity and viscosity significantly but sedimentation increased (p < 0.05). Optimum condition for production of functional Ayran determined as follow: Aloe vera gel concentration: 25.7%, reconstructed whey protein: 70%, salt: 0.58% and transglutaminase enzyme: 5 unit/100 mL.

Optimization and characterization of bacterial cellulose produced by Komagatacibacter xylinus PTCC 1734 using vinasse as a cheap cultivation medium.

In the present study, vinasse was used to produce bacterial cellulose (BC) by Komagatacibacter xylinus PTCC 1734. Central composite design (CCD) was utilized to evaluate the effects of vinasse concentration (%) and incubation time (Day) on different responses such as thickness as well as wet and dry weights of the produced BC membrane. The increase of vinasse concentration and incubation time caused an increase in the wet weight of BC; however, thickness decreased by increasing incubation time. The BC produced at the optimized conditions (40% vinasse and 10 days) was characterized and compared with the BC produced in Hestrin-Schramm medium as a control medium. Scanning electron microscopy (SEM) confirmed 3D network structure of BC. The average diameter of fibrils was in the range of 30-120 nm. In addition, the Fourier transform infrared spectroscopy (FT-IR) showed completely similar spectrum for both optimal and control samples. The X-ray diffraction (XRD) analysis approved the crystalline structure of the produced BC. Furthermore, the thermogravimetric analysis (TGA) test revealed no difference in the thermal stability of the optimum and control sample. According to the results, the vinasse, as a by-product, could be used as a cheap and suitable carbon source for the production of BC.

New formulation of vitamin C encapsulation by nanoliposomes: production and evaluation of particle size, stability and control release.

In the present study, the effects of different ratios of milk phospholipids, cholesterol and phytosterols (Campesterol) powder (50-100%, 0-50%, and 0-50%, respectively) and sonication time (20, 25, 30, 35 and 40 min) were investigated to produce a new formulation of nanoliposomes for encapsulation of vitamin C. The results showed that increasing the time of sonication and decreasing the ratio of phospholipid to phytosterol significantly decreased nanoliposomes' particle size (p < 0.05). The maximum encapsulation efficiency was obtained at 35 and 40 min of sonication time and 75-25 ratio of phospholipid: phytosterol. Also, reducing the sonication time in the same ratio of phospholipid/phytosterol caused to increase the controlled release. The highest stability of vitamin C during 20 days was obtained in the ratio of 75-25 (phospholipids: campesterol). The results showed a positive effect of cholesterol replacement with campesterol on encapsulation efficiency, control release and stability of vitamin C in nanoliposomes.

Exopolysaccharides production by Lactobacillus acidophilus LA5 and Bifidobacterium animalis subsp. lactis BB12: Optimization of fermentation variables and characterization of structure and bioactivities.

In this study, the most important variables (incubation temperature, fermentation time and yeast extract concentration) responsible for the exopolysaccharides (EPSs) production by Lactobacillus acidophilus LA5 and Bifidobacterium animalis subsp. lactis BB12 were screened. The EPSs synthesize by LA5, BB12, and their co-culture were successfully optimized and were 349.82 ±â€¯5.39, 146.83 ±â€¯3.99 and 187.02 ±â€¯1.54 mg/L, respectively. GC-MS analysis indicated that the purified EPSs are heteropolysaccharide and consisted of glucose, galactose, glucuronic acid, and xylose. The FT-IR analysis was used to investigate functional groups of purified EPSs and NMR analysis was used to study the structure of them. The DSC, TGA and DTG analysis of the extracted EPSs showed that they had high thermal stability and degradation temperature. The results of bioactivity analysis indicated that maximum DPPH and hydroxyl radicals scavenging activity were 59.30 ±â€¯1.95, 56.76 ±â€¯0.79, 62.33 ±â€¯1.02% and 59.94 ±â€¯1.68, 46.40 ±â€¯0.73, 53.54 ±â€¯0.76%, respectively for the EPSs of LA5, BB12, and their co-culture. Additionally, reducing power of the produced EPSs by LA5, BB12, and their co-culture were 1.047 ±â€¯0.001, 1.270 ±â€¯0.045 and 1.139 ±â€¯0.018, respectively. Consequently, all these results showed that the EPSs produced by LA5, BB12, and their co-culture had a high potential as natural antioxidants or bioactive additive in the food industry.