Control Yogurt Research Articles

Cinnamomum zeylanicum and Curcuma longa incorporated dairy yoghurts with hindered glycaemic properties for healthy people

This study mainly compare glycaemic responses of a control yoghurt (typical dairy yoghurt) against two novel yoghurt products with added spices oleoresins (Cinnamon yoghurt - Cinnamomum zeylanicum , turmeric yoghurt - Curcuma longa ) using 16 healthy volunteers in a randomized crossover study. Blood glucose concentrations were measured at fasting state and 30, 45, 60, 90, 120 min following the ingestion, using a Blood Glucose Monitoring System and blood glucose response curves were plotted. Nutritional and physicochemical properties were also compared and no significant differences ( P > 0.05) were observed between novel yoghurts and the control within the storage period. Significant reductions in peak blood glucose concentration and area under the curve (AUC) ( P < 0.05) for both novel products compared to standard dairy yoghurt was observed; revealing the reduction of glycaemic impact by spice ingredients. Peak reductions of glucose concentration for cinnamon yoghurt was 9.61%, for turmeric yoghurt was 9.26%; they were considerably lower compared to the control. Mean peak serum glucose concentration for control, cinnamon yoghurt and turmeric yoghurt were (113.38 ± 6.39), (102.50 ± 6.00), (102.88 ± 5.38) mg/dL respectively and mean AUC were (11 951 ± 523), (11 012 ± 611), (10 941 ± 530) ((mg/dL)*min) respectively. Hence novel yoghurt products are proven to be excellent sources in reducing postprandial blood glucose responses.

PROXIMATE AND SHELF LIFE EVALUATION OF SOYMILK YOGHURT WITH ADDED SACCHAROMYCES BOULARDII

The effect of adding Saccharomyces boullardii in soya yoghurt was studied. The control was made with soya milk and traditional starter culture (Lactobacillus bulgaricus and Streptococcus thermophilus) while the other three treatments were made by adding 1%, 2%, 3% of S. boulardii with traditional yoghurt starter. Proximate composition of all yoghurt treatments were determined after fermentation time. Shelf-life evaluation of yoghurt treatment were observed during the storage time. During the proximate composition evaluation, treatment with 3% S. boulardii had highest moisture and protein content at 83.43±0.03 and 92±0.3 but least ash and carbohydrate content at 1.2±0.18 and 4.27±0.3. During shelf-life evaluation, titratable acidity and syneresis values of yoghurt with S. boulardii were slightly increased while pH and water holding capacity decreased compared with control yoghurt. After 21 days, S. boulardii counts were 5.89, 6.07 and 6.03 log.cfu/ml for yoghurt with 2% and 3% S. boulardii respectively whereas L. bulgaricus and S. thermophilius of yoghurt with 3% S. boulardii were 7.45 and 8.38 log.cfu/ml respectively. The addition of S. boulardii improved the survivability of the bacteria starter culture.

Characterization of exopolysaccharide-producing lactic acid bacteria from Taiwanese ropy fermented milk and their application in low-fat fermented milk.

ObjectiveThe aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk.MethodsPotential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4°C.ResultsTwo EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period.ConclusionThis study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.

Bifidobacterium animalis subsp. lactis BB-12 Protects against Antibiotic-Induced Functional and Compositional Changes in Human Fecal Microbiome.

The administration of broad-spectrum antibiotics is often associated with antibiotic-associated diarrhea (AAD), and impacts gastrointestinal tract homeostasis, as evidenced by the following: (a) an overall reduction in both the numbers and diversity of the gut microbiota, and (b) decreased short-chain fatty acid (SCFA) production. Evidence in humans that probiotics may enhance the recovery of microbiota populations after antibiotic treatment is equivocal, and few studies have addressed if probiotics improve the recovery of microbial metabolic function. Our aim was to determine if Bifidobacterium animalis subsp. lactis BB-12 (BB-12)-containing yogurt could protect against antibiotic-induced fecal SCFA and microbiota composition disruptions. We conducted a randomized, allocation-concealed, controlled trial of amoxicillin/clavulanate administration (days 1–7), in conjunction with either BB-12-containing or control yogurt (days 1–14). We measured the fecal levels of SCFAs and bacterial composition at baseline and days 7, 14, 21, and 30. Forty-two participants were randomly assigned to the BB-12 group, and 20 participants to the control group. Antibiotic treatment suppressed the fecal acetate levels in both the control and probiotic groups. Following the cessation of antibiotics, the fecal acetate levels in the probiotic group increased over the remainder of the study and returned to the baseline levels on day 30 (−1.6% baseline), whereas, in the control group, the acetate levels remained suppressed. Further, antibiotic treatment reduced the Shannon diversity of the gut microbiota, for all the study participants at day 7. The magnitude of this change was larger and more sustained in the control group compared to the probiotic group, which is consistent with the hypothesis that BB-12 enhanced microbiota recovery. There were no significant baseline clinical differences between the two groups. Concurrent administration of amoxicillin/clavulanate and BB-12 yogurt, to healthy subjects, was associated with a significantly smaller decrease in the fecal SCFA levels and a more stable taxonomic profile of the microbiota over time than the control group.

The impact of storage on the sensory, viscosity and chemical characteristics of yogurt fortified with oat β-glucan

Oat β-glucan has the potential of a functional additive to yogurt, however, texture analysis and chemical characteristics during storage of yogurt with the addition of this additive require more systematic research, which determines the relevance of the study. The aim of the research work was to analyze the feasibility of enriching yogurt with 0.3% oat β-glucan. A number of methods for obtaining new knowledge in the direction of developing healthy food products were used. It was found that yogurt with the addition of 0.3% oat β-glucan had water-holding capacity. All pH values ranged from 4.18 to 4.28, which are within the normal ranges for set-type yogurts. A higher viscosity of the experimental sample of yogurt compared to the control was established, and the highest values were 58560±2120 cp at 21 days for yogurt with the addition of 0.3% oat β-glucan. The viability of probiotic bacteria in yogurts was examined. During the whole storage period, the content of probiotics decreased, but yogurt with the addition of 0.3% oat β-glucan contained significantly more live probiotic bacteria compared to the control. The viability of probiotic bacteria of 0.3% oat β-glucan yogurt at 14 d (3.18±0.2×107 CFU/mL) was only slightly lower than that of control yogurt at 1 d (3.45±0.3×107 CFU/mL). This fully demonstrates that the addition of 0.3% oat β-glucan has a protective effect on probiotics in yogurt, which will be beneficial for human health. It was found that the addition of 0.3% oat β-glucan led to a decrease in adhesiveness, but an increase in hardness and stickiness during storage. The results of the sensory evaluation showed the highest acceptability values of 86.49 for 21 days of storage of yogurt with the addition of 0.3% oat β-glucan. The practical value of the research work lies in the developed yogurt containing 0.3% oat β-glucan being possibly to use as an innovative healthy dairy product

Effect of enzymatically hydrolyzed potato powder on quality characteristics of stirred yogurt during cold storage

This study evaluated the effect of supplemented enzymatically hydrolyzed potato powder (EHPP) for quality characteristics and the storage stability of stirred type yogurt in refrigerator storage. Six treatments of varying quantity of EHPP and whole milk powder (WMP) along with one control were prepared. The results revealed that the addition of EHPP significantly (p < .05) increased water holding capacity (WHC) and acidity, while pH and rheological properties (storage modulus and loss modulus) were decreased in comparison with control yogurt. However, treatment with 25 g EHPP/100 g WMP having 3% sugar (T4) improved physicochemical, textural, and rheological properties of stirred yogurt. The study presented the successful addition of the EHPP as ingredient for a new dairy product with ameleiorated functional and sensorial characteristics. However, a high amount of EHPP can negatively affect the desirable characteristics, especially WHC, texture, and rheological properties. Sensory scores including taste appearance and overall acceptance showed reduction trend in samples containing a high level of EHPP. The sensory analysis revealed that the optimized product showed better acceptability when compared with control yogurt during storage. The results suggested that an optimized product containing 25 g EHPP/100 g of WMP with 3% sugar (T4) has the potential for developing a new dairy product with high values added and consumer acceptance. Practical applications It is recommended that the addition of enzymatically hydrolyzed potato powder (EHPP) increases the yogurt acceptability which could be scaled up further at commercial scale, providing a reference for dairy products with the addition of starch-based ingredients as well as added market value because of potential functional properties of potato powder. The storage stability analysis revealed that the product could be used up to 21 days with preserved taste, aroma, and other quality characteristics without any additional preservative. Moreover, the novel EHPP not only improves the quality but also has numerous health benefits after combining with milk powder proteins.This study also highlights on the increased consumer’s acceptability and prolonged commercialization of dairy products.

QUALITY ASSESSMENT OF YOGURT ENRICHED WITH OAT AND CHICKPEA POWDERS AS SOURCE OF DIETARY FIBERS

The aim of this study was to evaluate the effect of addition of oat and chickpea powders on the rheological, physicochemical and sensory characteristics of yogurt. Yogurt was fortified with oat and chickpea powders at ratios of 1, 2 and 3% of each. Yogurt was stored at 5 ±2˚C and analyzed when fresh and after 5, 10 and 15 days of storage. Results showed that:Control yogurt had the lowest total solids (TS), fat, protein,ash and fibers contents compared with fortified yogurt treatments. The TS, fat ,protein, ash and fibers contents of yogurt containing oat and chickpea powders at different concentrations increased gradually by increasing the percentage added, Addition of oat and chickpea powders at different concentrations increased the pH in yogurt. Whereas, titratable acidity decreased with increased fortification ratio. Fortification of yogurt with oat and chickpea powders at different concentrations significantly decreased whey syneresis and increased viscosity compared with control yogurt and this increasing was proportional to the fortification ratio. Addition of oat and chickpea powders at different concentrations significantly increased phenolic contents and antioxidant activity of yogurt treatments and these increments were proportional to the fortification ratio. Yogurt treatments fortified with oat and chickpea powders at different concentrations had the lowest counts of total bacteria, yeast and moulds,Streptococcus salivarius subsp.thermophilus andLactobacillus delbruekii subsp. bulgaricuscounts. Total bacteria, yeast and moulds,Streptococcus salivarius subsp. thermophilus and Lactobacillus delbruekii subsp. bulgaricuscounts decreased with increasing the fortification ratio.Control yogurt had the lowest sensory evaluations values. Addition of oat and chickpea powders improved the organoleptic properties of fortified yogurt; the highest mean value was related to sample containing 3% oat powder.

Effect of whey protein- and xanthan-based coating on the viability of microencapsulated Lactobacillus acidophilus and physiochemical, textural, and sensorial properties of yogurt.

The goal of this study was to investigate the viability of microencapsulated and coated Lactobacillus acidophilus in yogurt during storage in a refrigerator for 28 days and in simulated gastrointestinal conditions. Furthermore, the effect of the microencapsulated and coated L. acidophilus on the physicochemical, textural, and sensory properties of yogurt was assessed. Lactobacillus acidophilus was microencapsulated in sodium alginate and coated with xanthan and/or whey protein. The coating led to the increase in the microcapsule diameter and the microencapsulation yield, while it led to the decreased moisture and water activity (aw) of the microcapsule. The survival of L. acidophilus microcapsule coated with whey protein and xanthan in yogurt during storage and exposure to simulated gastrointestinal conditions was significantly increased. Compared with free bacteria, the L. acidophilus microcapsule coated with whey protein and xanthan had the increased viability in yogurt until 2.16 log CFU/g during storage and 3.52 log CFU/g in simulated gastrointestinal conditions. After the 28th day of storage, a significant difference between the acidity and pH of yogurt containing coated and microencapsulated L. acidophilus and control yogurt was not observed. However, yogurt containing free L. acidophilus had lower pH and higher acidity and showed a significant difference (p < .05) with other samples. Although the coating of L. acidophilus microcapsule did not affect the sensory properties and gumminess of yogurt, it increased the firmness, adhesiveness, and viscosity of this product and caused a significant decrease in syneresis and cohesiveness. In general, the application of whey protein and xanthan coating on L. acidophilus microcapsule surface could increase the viability of this probiotic in yogurt during storage and in simulated gastrointestinal conditions and improve the texture attributes of yogurt.

Determination of Honey Varietals’ Impact on Bifidobacterium animalis ssp lactis Survivability in Commercial Yogurt Through Simulated In Vitro Digestion

ObjectivesConsumption of yogurt containing the probiotic Bifidobacterium animalis lactis DN-173 010/CNCM I-2494 (B. animalis) improves digestive health and quality of life in adults. To optimize the benefits of this probiotic, we aimed to test our hypothesis that yogurt with honey would increase the survivability of B. animalis under simulated gastrointestinal tract digestion conditions. MethodsPhase 1 tested four honey varietals (alfalfa, buckwheat, clover, and orange) at a final concentration of 20% w/w in yogurt containing B. animalis. Undiluted yogurt and yogurt with added sucrose or water (20% w/w) were included as control treatments. Phase 2 assessed clover honey at final concentrations of 20, 14, 10, 9, 8, 6, 4% w/w. Yogurt samples were subjected to in vitro simulated oral, gastric, and intestinal digestion using simulated salivary, gastric, and intestinal fluids, respectively. At four time points—pre-digestion, and after each phase of digestion (oral, gastric, intestinal)—probiotic cells were enumerated first by spread plating on MRS agar and incubated for 5 h at 37°C under anaerobic conditions. Then, plates were overlaid with MRS supplemented with lithium chloride and sodium propionate and incubated an additional 67 h prior to quantification of the probiotic colony forming units (CFU). ResultsPhase 1 demonstrated similar probiotic counts between honey varietals and controls after exposure to oral and gastric simulated fluids (< 1 Log CFU/g of probiotic reduction after gastric phase). There was comparable probiotic survival after the simulated intestinal phase for yogurt with the alfalfa, buckwheat, and orange honey varietals relative to control yogurt treatments. However, higher B. animalis survivability was observed in yogurt with clover honey after exposure to simulated intestinal fluids (∼3.5 Log CFU/g reduction) compared to all control treatments (∼5.5 Log CFU/g reduction, P < 0.05). Phase 2 revealed that 20%, 14% and 10% w/w clover honey similarly supported B. animalis survivability after exposure to simulated intestinal fluids. ConclusionsThese results demonstrated that clover honey increased B. animalis survivability in yogurt during in vitro digestion when provided at doses equivalent to 1 to 2 tablespoons per serving (170g) of yogurt. Funding SourcesThe National Honey Board.

Evaluation of the Effect of Essential Oil Addition on the Quality Parameters and Predicted Shelf Life of Potato Yogurt

Potato, the third most important food crop worldwide, is rich in nutrients but low in protein. In contrast, milk is rich in protein. Yogurt produced through the cofermentation of potatoes and milk is a highly nutritious food. The quality and shelf life of yogurt are important topics in the dairy industry. The objective of this study was to explore the effect of the addition of essential oil (EO) on the shelf life and quality of potato yogurt. The antimicrobial effects of several EOs, the effect of perilla leaf EO (PLEO) concentration on potato yogurt, and the volatile flavor components of PLEO and PLEO potato yogurt were evaluated. The effects of storage time and temperature on the pH, microbial counts, and sensory characteristics of PLEO potato yogurt also were analyzed to establish a shelf-life model. PLEO had an antimicrobial effect and was the appropriate EO for use in the potato yogurt. A total of 69 compounds were detected in PLEO, and limonene was the main compound. PLEO had an effect on the pH, sensory characteristics, and viable bacterial counts of potato yogurt during storage. The optimal concentration of added PLEO was 0.04%. PLEO had considerable influence on volatile flavor components, and the consumer acceptance of 0.04% PLEO potato yogurt was higher than that of potato yogurt without PLEO in the later stage of storage. The shelf life of potato yogurt with PLEO was 6 days longer than that of the control yogurt. PLEO also improved the concentrations of active terpene substances in potato yogurt. The prediction models based on pH and sensory scores at 5°C were established as A = A0e0.00323t and A = A0e0.00355t, respectively. Comparison of the accuracy factor and the deviation factor of the models revealed that the sensory prediction model was more accurate than the pH prediction model. The results of this study provide theoretical and data support for the industrial development of yogurt with EOs, including extension and prediction of its shelf life.

Effect of date palm (Phoenix dactylifera L.) spikelets extract on the physicochemical and microbial properties of set-type yogurt during cold storage

The aim of this study was to investigate the impact of different concentrations (0.5% and 1.0%) of date palm spikelet extracts (DPSEs) from Reziz (Rz) and Khalas (Kl) cultivars on the physicochemical and microbiological properties of cow's yogurt during cold storage. At the beginning of storage, DPSEs increased the water holding capacity (WHC), cohesiveness, springiness, adhesiveness, and a* values and decreased the viscosity, hardness, L*, and b* values of fortified yogurt compared to control. DPSEs did not affect the viable counts of LAB (Streptococcus thermophilus and Lactobacillus bulgaricus), pH, and acidity of yogurt at the beginning of storage; however, during storage, significant variations in these properties were observed between samples. As the storage time progressed, a significant reduction in pH, WHC, viable counts of LAB, viscosity, texture attributes, and color of the control yogurt was observed, whereas DPSE-fortified yogurts were stable or showed an increase in these properties, with some exceptions. Overall, DPSEs stabilized the gel matrix, maintained the growth of LAB, and improved the quality of yogurt during cold storage. In conclusion, DPSEs can improve the stability of yogurt gel during handling and storage because of the antioxidant activity of the extracts, thereby enhancing consumer's acceptability of the product.

Effect of Two Combined Functional Additives on Yoghurt Properties.

The aim of the research was the analysis of yoghurts enriched with blue honeysuckle berries dry polyphenolic extract and new preparation of resistant starch. The additives were introduced individually at concentration 0.1% (w/v) and in mixture at final concentration of 0.1 and 0.2% of both components. Yogurt microflora, pH, and its physicochemical and antioxidant properties were examined over 14 days of storage under refrigerated conditions. Studies showed that both substances can be successfully used in yoghurt production. Yoghurt microflora es. S. thermophilus and Lb. delbrueckii subsp. bulgaricus counts appeared to be higher in samples supplemented with these additives comparing to control yoghurt by 3–8%. More stimulating effect on their growth, especially on S. thermophilus, revealed resistant starch. Addition of this polysaccharide improved also the rheological properties of yogurts, which showed higher viscosity than samples produced without it. Addition of honeysuckle berries preparation significantly influenced the yogurts’ color, giving them deep purple color, and their antioxidant potential. During storage, contents of anthocyanin and iridoid compounds were decreasing, but antioxidant activity in the products remained stable.

Formulation and characterization of yogurt prepared with enzymatically hydrolyzed potato powder and whole milk powder.

The online version contains supplementary material available at 10.1007/s13197-021-05112-6.

Selection of potential probiotics with cholesterol-lowering properties for probiotic yoghurt production.

From 61 lactic acid bacteria (LAB) isolates, three had good cholesterol-lowering properties, with Limosilactobacillus fermentum KUB-D18 having the highest cholesterol assimilation (68.75%) (51 µg/109 CFU). In addition, Lactiplantibacillus pentosus HM04-25 and L. pentosus HM04-3 had the two highest levels of bile salt hydrolase (BSH) activity (22.60 and 21.45 U/mL, respectively). These three strains could resist four antibiotics (aztreonam, vancomycin, teicoplanin, and nalidixic). However, fortunately, they contained no mobile antibiotic resistance genes. To evaluate the influence of probiotic strains in yoghurt production, L. fermentum KUB-D18, L. pentosus HM04-25, or L. pentosus HM04-3 were simultaneously cultured with commercial yoghurt starter (YF-L812) and incubated at 43 °C for 6 h. During yoghurt fermentation, the total bacteria in the yoghurt tended to increase from 7.39 to 8.90 log CFU/mL. The growth rates of two probiotic strains (L. pentosus HM04-25 and L. pentosus HM04-3) were stable at 6.06 to 6.62 log CFU/mL. Only the rate for L. fermentum KUB-D18 increased (to 7.5 log CFU/mL). These three probiotics did not affect the physical characteristics of yoghurt. The total soluble solids, pH, and titratable acidity values of the probiotic yoghurts were similar to the control yoghurt at 30Brix, 4.91, and 0.90%, respectively. The firmness values of the probiotic yoghurts and the control were not significantly different (p > 0.05). Differentiation of the appearance of color, odor, flavor, and texture between the control yoghurt and the probiotic yoghurts was investigated using 56 volunteers and no significant differences were identified. Additionally, sensory evolution revealed that the acceptability of the probiotic yoghurts was higher than for the control (p ≤ 0.05). Therefore, the three probiotic strains with cholesterol-lowering properties had potential in future yoghurt production.

Effects of Bacillus coagulans as an adjunct starter culture on yogurt quality and storage

Bacillus coagulans has been widely studied for its probiotic properties. Therefore, identifying a strain that can be used as an adjunct starter culture for yogurt production would have commercial value. In this study, 30 B. coagulans strains were isolated from vegetable samples from 11 provinces or autonomous regions in China, and their pan-genomic and phylogenetic characteristics were analyzed. Phylogenetic analysis categorized 30 strains into 4 different subphylotypes, including subtype I (11 isolates), subtype II (7 isolates), subtype III (11 isolates), and subtype IV (1 isolate). Four B. coagulans strains (B. coagulans-70, B. coagulans-78, B. coagulans-79, and B. coagulans-100) were randomly selected from each subphylotype of the phylogenetic tree as adjunct starter cultures. Compared with the other tested strains, B. coagulans-70 showed the highest count in yogurt at the end of the manufacturing period. Comparative genome analysis indicated that the different bacterial levels of B. coagulans strains in yogurt may be associated with the abundance of genes related to carbohydrate transport and metabolism (e.g., sucrose utilization). Finally, differences in texture and volatile flavor compound profiles were observed between the yogurt samples. Compared with the other groups, the addition of B. coagulans-70 exerted a positive effect on the appearance and texture of yogurt products. Volatile analysis showed increased quantities of 2-heptanone, 2-nonanone, amyl alcohol, and 2-hydroxy-3-pentanone in the B. coagulans-70 group compared with control yogurts. These results above combined with the results of a sensory evaluation indicated that B. coagulans-70 is the most suitable strain for further use in functional dairy product development.

Evaluation of lactose oxidase as enzymatic antifungal control for Penicillium spoilage in yogurt

In this study, we investigated the antifungal activity of lactose oxidase (LO) as a potential biopreservative in dairy products. Our study objectives were to screen antifungal activity of LO against common mold strains, to detect the minimum inhibitory level of LO against the same strains, and to understand how LO affects the pH and lactic acid bacteria (LAB) counts in set yogurt. Five mold strains (Penicillium chrysogenum, Penicillium citrinum,Penicillium commune,Penicillium decumbens,and Penicillium roqueforti) were used throughout study. These strains were previously isolated from dairy manufacturing plants. Throughout the study, yogurts were stored at 21 ± 2°C for 14 d. Antifungal activity of LO was screened using 2 enzyme levels (1.2 and 12 g/L LO) against selected strains on the surface of a miniature laboratory set-yogurt model. For all tested strains, no visible mold growth was detected on the surface of yogurts covered with LO compared with control yogurt without LO. The minimum inhibitory level of LO against each strain was further investigated using 4 enzyme levels (0.12, 0.48, 0.84, and 1.2 g/L LO) on the miniature laboratory set-yogurt model. We detected 0.84 g/L LO as the minimum level inhibiting visible hyphal growth across strains. The minimum inhibitory level of LO varied for each individual strain. To study the effect of LO on the pH of yogurt, miniature laboratory set-yogurt models were covered with different enzyme levels (0.12, 0.48, 0.84, 1.2, and 12 g/L LO). At d 14, a difference was detected comparing pH values of treatments to control with no LO. Commercial low-fat set yogurt was used to study the effect of LO on LAB survival when yogurt surface was covered with 0.84 g/L LO under the same experimental conditions. Control with no LO was included. At d 14, 3 levels of catalase were added (0, 0.01, and 0.1%) to each treatment. To enumerate LAB, homogenized samples were plated on de Man, Rogosa, and Sharpe agar and incubated. Yogurts with 0.84 g/L LO had lower LAB counts compared with control yogurts, and catalase level did not have a significant effect on LAB counts. Our results demonstrated potential antifungal efficacy of LO against common spoilage organisms in dairy products with residual lactose and relatively low pH. Manufacturers should establish efficacy of LO against mold strains of interest and determine the effects of LO on organoleptic properties and LAB survival in set yogurt.

Physicochemical Analysis of Yogurt Produced by Leuconostoc mesenteroides H40 and Its Effects on Oxidative Stress in Neuronal Cells

Leuconostoc mesenteroides H40 (H40) was isolated from kimchi, and its probiotic properties and neuroprotective effect was evaluated in oxidatively stressed SH-SY5Y cells. H40 was stable in artificial gastric conditions and can be attached in HT-29 cells. In addition, H40 did not produce β-glucuronidase and showed resistant to several antibiotics. The conditioned medium (CM) was made using HT-29 cells refined with heat-killed probiotics (Probiotics-CM) and heated yogurts (Y-CM) to investigate the neuroprotective effect. Treatment with H40-CM not only increased cell viability but also significantly improved brain derived neurotropic factor (BDNF) expression and reduced the Bax/Bcl-2 ratio in oxidatively stress-induced SH-SY5Y cells. Besides, probiotic Y-CM significantly increased BDNF mRNA expression and decreased Bax/Bcl-2 ratio. The physicochemical properties of probiotic yogurt with H40 was not significantly different from the control yogurt. The viable cell counts of lactic acid bacteria in control and probiotic yogurt with H40 was 8.66 Log CFU/mL and 8.96 Log CFU/mL, respectively. Therefore, these results indicate that H40 can be used as prophylactic functional dairy food having neuroprotective effects.

Bioactive compounds in jamelão yogurt (Syzygium cumini L)

The jamelão fruit has been used in traditional Indian medicine and has recently attracted interest as a functional food, as it is rich in anthocyanins. Anthocyanins are of interest of the food industry due to their antioxidant power, attractive color and stability in acid-rich foods. This research used the gelation process with sodium alginate solution to obtain bioactive yogurt from the production of jamelão capsules added to natural yogurt. The proportion was 80% yogurt and 20% jellybean pulp capsules. The treatments were control yogurt (without the addition of jamelão capsules), jamelão capsules and bioactive yogurt (with the capsules). The objective was to study the antioxidant activity, physical-chemical, nutritional and microscopic stability of the product kept under refrigeration for 28 days at 4±1ºC. The addition of jamelão capsules in the yogurt changed the product's physical properties (increased humidity and decreased Brix and ash). There was an increase in the amount of phenols and anthocyanins, in addition to the antioxidant potential at 28 days of storage. The interior of the microcapsules was composed of a mesh structure through which the encapsulated material was distributed, as the capsules can be added to yogurt, to improve the antioxidant and nutritional capacity, which proves to be a promising and viable alternative.

A Newly Developed Synbiotic Yogurt Prevents Diabetes by Improving the Microbiome-Intestine-Pancreas Axis.

The prevalence of type 2 diabetes mellitus (T2D) is increasing worldwide, and there are no long-term preventive strategies to stop this growth. Emerging research shows that perturbations in the gut microbiome significantly contribute to the development of T2D, while microbiome modulators may be beneficial for T2D prevention. However, microbiome modulators that are effective, safe, affordable, and able to be administered daily are not yet available. Based on our previous pro- and prebiotic studies, we developed a novel synbiotic yogurt comprised of human-origin probiotics and plant-based prebiotics and investigated its impact on diet- and streptozotocin-induced T2D in mice. We compared the effects of our synbiotic yogurt to those of a commercially available yogurt (control yogurt). Interestingly, we found that the feeding of the synbiotic yogurt significantly reduced the development of hyperglycemia (diabetes) in response to high-fat diet feeding and streptozotocin compared to milk-fed controls. Surprisingly, the control yogurt exacerbated diabetes progression. Synbiotic yogurt beneficially modulated the gut microbiota composition compared to milk, while the control yogurt negatively modulated it by significantly increasing the abundance of detrimental bacteria such as Proteobacteria and Enterobacteriaceae. In addition, the synbiotic yogurt protected pancreatic islet morphology compared to the milk control, while the control yogurt demonstrated worse effects on islets. These results suggest that our newly developed synbiotic yogurt protects against diabetes in mice and can be used as a therapeutic to prevent diabetes progression.

Formulation of yogurt with banana peel extracts to enhance storability and bioactive properties

Banana peel extract as a source of phenolic compounds was fortified in yogurts. The addition of extract in yogurts exhibited a dose-dependent relationship and had significantly (p < .05) higher TPC, DPPH•, and ABTS+• scavenging ability, α-glucosidase inhibitory activity than control yogurts. The value of TPC, ABTS+•, and DPPH• scavenging ability, and α-glucosidase inhibitory activity of 100 µl extract-fortified yogurts were 502.40 ± 9.29 mg GAE/kg yogurt, 61.09 ± 2.66%, 70.69 ± 3.66%, and 54.21 ± 0.60%, respectively, at 28 days of refrigeration storage. The fortification of extract in yogurts significantly reduced the lipid oxidation and increased the viscosity, respectively, but had no significant influence on color, syneresis, pH, and lactic acid of the yogurts during storage. The extract up to 600 µl per 100 g yogurts received “like very muchˮ liking score by sensory evaluation. The study demonstrated that banana peel extract has the potential to be used as functional food ingredients for promoting human health and extending the shelf life of the products. Novelty Impact Statement Yogurts had significantly increased total phenolic content and exerted high antioxidant and antidiabetic activities on fortification of banana peel extract as sources of phenolic compounds. Fortification of extracts did not affect yogurt's quality parameters (color, pH, acidity, and whey separation), but significantly delayed lipid oxidation during storage. Fortified yogurts were acceptable by consumers based on sensory evaluation.