Search Results (254)

This study aimed to microencapsulate Limosilactobacillus reuteri DSM 17938 to enrich soy yogurt flavored with peach jam. The effect of three concentrations of alginate and coating chitosan were evaluated in terms of probiotic viability, and the physicochemical and sensory properties of soy yogurt. Lim. reuteri was microencapsulated in alginate (1, 2, and 3%) and coated with chitosan (0, 0.4, and 0.8%). Soymilk was fermented using Lactobacillus bulgaricus and Streptococcus thermophilus. Soy yogurt was combined with probiotic beads and peach jam and stored for 27 days at 4 °C. The pH, titratable acidity, and probiotic viability of probiotic peach soy yogurt (PPSY) were determined during storage. Alginate at 3% and alginate (2%) coated with 0.4% chitosan maintained probiotic counts at 8 and 7.5 log CFU/g after 27 days. The pH of PPSY decreases rapidly and drastically during storage when probiotic-free cells are added. The PPSY containing alginate (3%) beads, alginate (2%) coated with chitosan (0.4%), and probiotic-free cells had a similar level of acceptance in color, texture, and odor (p > 0.05), while flavor and overall acceptability were significantly higher (p < 0.05) in PPSY with probiotic beads. These findings support the use of microencapsulation strategies in developing functional plant-based probiotic foods. Full article

Yogurt fortified with polyphenols, as a new type of functional yogurt, exhibits high quality and good antioxidant activity. However, the effects of black garlic polyphenols (BGP) on the quality of solidified yogurt have been scarcely reported. Therefore, the effects of different levels (0.1–0.4%) of BGP on the sensory scores, physicochemical properties, rheological properties, texture properties, antioxidant activity and polyphenol content of solidified yogurt were studied. The results showed that the total sensory scores of yogurt with 0.2% and 0.4% levels of BGP addition were both above 80. BGP addition significantly decreased the water-holding capacity and pH values of yogurt, compared with the yogurt without BGP addition. The yogurt with a 0.4% level of BGP had the highest titratable acidity of 89.84° T. In addition, the storage modulus (G’) and loss modulus (G”) of yogurt increased with the addition of BGP. The gel strength, chewiness and hardness of yogurt significantly decreased with an increase in BGP addition. The content of quercetin and caffeic acid in the yogurt with the addition of 0.1–0.4% BGP was 0.53–1.79 mg/g and 2.13–4.98 mg/g, respectively. The antioxidant activity and total phenolic acid content of yogurt significantly increased with an increment in BGP addition. The 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging activity, ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of yogurt with a 0.4% level of BGP increased by 52.79%, 57.31% and 42.51%, respectively, compared to the yogurt without BGP addition. This study provides a theoretical basis for the development of novel yogurt with high antioxidant activity. Full article

Black soybean is known for its antioxidant and anti-inflammatory properties that help prevent several degenerative diseases, but in the Western diet, it is poorly used, despite the interest in foods rich in bioactive compounds. This study aimed to formulate a black soybean yogurt (BSY) fermented by a probiotic culture of L. acidophilus and evaluate the nutritional and bioactive profiles, the total antioxidant capacity, and complementary parameters during fermentation and storage for one month. We also evaluated the potential for acceptance by Rio de Janeiro consumers (n = 103). The final BSY water content was 92.8%. The dry matter contained 50.2% protein, 20.1% lipid, 5.9% ashes, 23.8% carbohydrates, and other constituents, including 1% sucrose, 5.9% α-galactosides, 26.9 mg/100 g anthocyanins (mainly cyanidin-3-glucoside), 140.5mg/100 g isoflavones (mainly genistin and daidzin). Titratable acidity was 0.44% and pH 4.5. In the sensory test, 12% sucrose and fruit extracts (strawberry, prune, and grape) were added individually to the product to evaluate the acceptability. The sweetened strawberry extract offered the highest acceptability, with a 7.6 score in a nine-point hedonic scale, against a 5.6 of the sweetened control with no fruit extract. Furthermore, all products scored well in the clusters with assessors who consumed soy products often and daily (total n = 26), with the strawberry-flavored one scoring, on average, 8 or 9. One month storage at 8 ± 2 °C caused a 22% decrease in the anthocyanins content and no significant change in isoflavones, titratable acidity, and pH. Fermentation and the addition of a sweetened fruit extract proved to be promising tools to increase the consumption of black soy milk in the West. Full article

Increasing awareness of the negative health effects associated with high sugar intake has led to a growing demand for reducing added sugar in food products. In this study, the antioxidant properties of commercial yogurts containing pasteurized fruits were evaluated and compared with natural yogurts freshly enriched with 3–20% thawed fruits (bilberries, cherries and strawberries). Additionally, yogurts enriched with cornelian cherry were analyzed. Antioxidant activity was assessed using the ABTS and DPPH methods, along with measurements of total polyphenol content and reducing power. The effect of fruit addition on the number of yogurt bacteria was also investigated. The results showed that the addition of fruits significantly increased the yogurts’ ability to neutralize free radicals, attributed to the presence of natural antioxidants and polyphenols. The addition of fruits helped maintain the vitality of lactic acid bacteria, with bacterial counts remaining well above the minimum threshold of 10⁷ cfu/g. The findings demonstrated that cornelian cherry has great potential as a source of polyphenols with antioxidant properties. These results confirm the high nutritional value of yogurts enriched with thawed fruit, which may serve as a valuable component of a healthy diet and a healthier alternative to sweetened yogurts commonly available in stores. Full article

This study aimed to assess the viability of a new gelling agent, formed by a combination of disodium 5-guanylate and lactic acid, as a potential substitute for conventional hydrocolloids in yogurt production. Six different yogurt samples containing novel gel (combination of lactic acid and disodium 5-guanylate), disodium 5-guanylate, gelatin, agar-agar, lactic acid, and a control yogurt without any hydrocolloid or other additives, were studied. As expected, all the yogurt samples exhibited shear-thinning behavior. The novel gel yogurt, when compared to the control yogurt, displayed similar viscosity at a low shear rate of 4.5 s⁻¹ (mimicking the shearing during manual scooping with a spoon) and lower viscosity at a shear rate of 60.8 s⁻¹ (mimicking the agitation in the mouth). Notably, the novel gel yogurt demonstrated a lower flow behavior index (0.13 vs. 0.40 on day 1), reduced syneresis (23.37% vs. 33.75%), and had a higher consistency coefficient (9.2 vs. 7.25 on day 1) compared to the control yogurt. The novel gel yogurt exhibited superior rupture strength compared to yogurt with other hydrocolloids, such as gelatin and agar-agar, and similar brittleness to yogurt with gelatin. Microstructural analysis revealed an aggregated and compact protein network in the novel gel yogurt, analogous to the yogurt with gelatin. Sensory evaluations indicated no significant differences between the control and the novel gel yogurt. Therefore, the novel gelling agent studied can serve as a cost-effective alternative in yogurt production, compared to conventional hydrocolloids that are in short supply, in high demand, and expensive in the market. Full article

Yogurt fortification with purslane (Portulaca oleracea L.) can improve its health benefits, but it may alter the fermentation step and its final properties. Thus, the current study investigated the suitability of Fourier Transform-Near Infrared (FT-NIR) spectroscopy for in-line monitoring of lactic acid fermentation of purslane-fortified yogurt compared with fundamental rheology. Changes in the yogurt properties during storage were also assessed. Set-type yogurts without and with lyophilized purslane leaves (0.55%) were produced and stored at 4 °C for up to 18 days. Lactic acid bacteria concentrations before and after fermentation at 43 °C for 2.5 h showed that the presence of purslane did not interfere with bacterial growth. The purslane addition increased the milk viscosity, resulting in a yogurt with complex modulus values higher than those of the reference sample (360 vs. 172 Pa). The elaboration of spectral data with Principal Component Analysis and the Gompertz equation enabled calculation of the kinetic critical points. Applying the Gompertz equation to the rheological data, it was evident that FT-NIR spectroscopy detected earlier the fermentation progression (the critical times were about 18% earlier on average), thus enabling better control of yogurt production. No significant changes in microbial or textural properties were noted during yogurt storage, demonstrating that purslane addition did not affect the product stability. Full article

Probiotics and phenolic compounds provide benefits to humans when they are consumed in adequate amounts. However, these materials are not very stable and can easily be degraded during processing and storage; so, they must be protected. This study evaluated the encapsulation of Lactiplantibacillus fabifermentans BAL-27 ITTG and phenolic compounds from coffee husks via alginate beads. The research considered variables such as alginate concentration (1.5% and 3%), crosslinking time (8 and 20 min), and the inclusion of chitosan. A 2³ factorial design was employed, and the effects were analyzed via ANOVA (p < 0.05). The encapsulation efficiency of the probiotic exceeded 80%, and its viability following gastrointestinal simulation ranged from 73.65% to 85.34%. The phenolic compounds achieved encapsulation efficiencies of up to 20%. In yogurt, the alginate beads maintained probiotic viability at approximately 9 Log₁₀ CFU/g and preserved the stability of the antioxidant compounds over 28 days. Moreover, the incorporation of beads did not adversely affect the physicochemical properties or sensory acceptance of the yogurt, supporting their potential application in functional foods. Full article

Yogurt is a highly consumed dairy product valued for its nutritional and probiotic properties. Its production involves the use of lactic acid bacteria, which drive biochemical transformations during fermentation. Optimizing fermentation time without compromising yogurt quality is essential for improving processing efficiency. Pulsed electric fields (PEFs) constitute a promising technology that stimulates microbial activity. In this study, a yogurt starter inoculum suspended in milk (IM) with different fat content (0.5–2.8%) was treated with low-intensity PEFs (1 kV/cm, 800–1600 µs) to enhance fermentation kinetics. pH, soluble solids, lactose, lactic acid, and riboflavin concentrations were monitored during 6 h, comparing PEF-treated IM (PEF-IM) and untreated IM (C-IM). PEF-treatments applied to IM reduced the fermentation time of inoculated milk by 4.3–20.4 min compared to C-IM. The lowest fermentation time (5.1 ± 0.16 h) was observed in milk added with PEF-IM (2.8% fat) treated at 1 kV/cm for 1600 µs. Milk inoculated with PEF-IM exhibited enhanced lactose consumption (1.6–3.1%) and higher lactic acid production (7.2%) than milk with C-IM. Riboflavin concentration (0.9–7%) decreased between 2 and 4 h, but it stabilized at the end of fermentation. Obtained results suggest that PEFs promote reversible electroporation in microbial cells, facilitating nutrient uptake and acidification, making it a promising assisted-fermentation approach to improve yogurt production. Full article

This study compared yogurts containing coffee (cascara and silverskin) and wine-making (pomace, skin, and seed) byproduct extracts as novel ingredients. For this purpose, the analysis of the sensory acceptance, basic information on phytochemical profile, and health-promoting properties of novel yogurt formulations were carried out. The antioxidant (ORAC, ABTS, DPPH, and intracellular ROS), antidiabetic (α-glucosidase inhibition), and anti-inflammatory (NO assay) properties of the yogurts depended on the type of byproduct extract and concentration used. Among the studied formulations, coffee cascara yogurt showed a high sensory acceptance (6.96), high overall antioxidant capacity (significantly higher (p < 0.05) values of TPC and antioxidant capacity measured by ORAC, ABTS, and DPPH than control yogurt), the best antidiabetic properties (inhibition of α-glucosidase activity of 83%), and a significant (p < 0.05) anti-inflammatory effect used as an ingredient at a final concentration of 10 mg/mL of food. The antioxidant and antidiabetic properties of cascara yogurt were also observed after in vitro digestion, which may be ascribed to unidentified bioactive compounds such as metabolites of phytochemicals and proteins generated during the physiological process. Overall, we developed a healthy, tasty, and sustainable coffee cascara yogurt containing antioxidant and antidiabetic compounds, which may be bioaccessible for their in vivo effects. The cascara yogurt can be consumed by the general public since the caffeine concentration in the food is within the recommended range for all population groups and it does not seem bioaccessible after the digestion of the food. Full article

This study demonstrates that Bacillus subtilis GDAAS-A32-derived postbiotics (BSP) enhance yogurt production by optimizing lactic acid bacteria (LAB) viability and functionality. BSP enhanced the growth kinetics and biomass accumulation of Streptococcus thermophilus and Lactobacillus bulgaricus in both an anaerobic and aerobic pure system. The addition of BSP significantly increased the viable cell counts of S. thermophilus and L. bulgaricus, milk-clotting activity, sensory properties, and extracellular polysaccharide content and improved the rheological properties. Moreover, BSP elevated viable counts of S. thermophilus and L. bulgaricus to 6.18 × 10⁸ CFU/g and 1.03 × 10⁸ CFU/g, respectively, by day 7—representing 11.3-fold and 9.3-fold increases versus controls at 20% supplementation. Metabolomic signatures confirmed peptidoglycan reinforcement and flavor enhancement. Mechanistically, BSP supplementation might reduce urate and H₂O₂ toxicity through NH₃-mediated proton neutralization and oxygen scavenging, while establishing a pyrimidine salvage network and redirecting one-carbon metabolism, resulting in enhanced stress tolerance and significant improvements in bacterial viability. Full article

The swift progression of nanotechnology has transformed the food and dairy industries through the facilitation of functional foods, nutraceuticals, and antimicrobial systems. This review examines the environmentally friendly synthesis of nanoparticles (NPs) through the utilization of microorganisms, offering a sustainable and biocompatible alternative to traditional physical and chemical approaches. This study primarily aims to investigate the contemporary trends, mechanisms, and microbial species associated with NP biosynthesis, as well as to evaluate NPs’ techno-functional applications in food and dairy processing. The specific objectives encompass analysis of the synthesis pathways—both intracellular and extracellular—utilized by bacteria, fungi, yeasts, and algae. Additionally, an evaluation of the physicochemical properties and biological activities (including antibacterial, antioxidant, and antifungal effects) of synthesized NPs will be conducted, alongside the identification of their potential applications in food preservation, packaging, and fortification. The review emphasizes notable advancements in laboratory-scale applications, especially concerning yogurt fortification, biofilm suppression, and antimicrobial food coatings. Nonetheless, commercial application is constrained by issues related to scalability, purification, stability, regulatory adherence, and toxicity evaluation. Future investigations ought to focus on enhancing bioreactor systems, leveraging microbial consortia, utilizing food and agricultural waste as substrates, and implementing omics technologies to elucidate biosynthetic mechanisms. Furthermore, the standardization of synthesis protocols and the improvement of regulatory frameworks will be crucial in closing the divide between experimental achievements and NPs’ application in industry. In a nutshell, the microbial-mediated green synthesis of NPs offers a promising pathway for the advancement of safe, sustainable, and functional innovations within the food and dairy sectors. Full article

Lactic acid bacteria (LAB) isolated from plant sources are gaining increasing attention due to their potential probiotic and postbiotic functionalities. In the present study, Limosilactobacillus fermentum isolated from Prunus padus (bird cherry) was evaluated for its physiological, functional, and technological attributes for application in fermented dairy products. The strain was isolated through anaerobic fermentation and identified using API 50 CHL and 16S rRNA sequencing. Its acid tolerance, antioxidant capacity, antibacterial effects, and hemolytic activity were assessed. The cell-free supernatant (CFS) was evaluated for thermal and pH stability. Fermentation trials were conducted using both mono- and co-culture combinations with the commercial yogurt starter strain YC-380. Physicochemical properties, viable cell counts, and viscosity were monitored throughout fermentation and refrigerated storage. The L. fermentum isolate exhibited strong acid resistance (48.28% viability at pH 2.0), non-hemolytic safety, and notable DPPH radical scavenging activity. Its CFS showed significant antibacterial activity against five Escherichia coli strains, which remained stable after heat treatment. Co-cultivation with YC-380 enhanced fermentation efficiency and improved yogurt viscosity (from 800 to 1200 CP) compared to YC-380 alone. During 24 days of cold storage, co-cultured samples maintained superior pH and microbial stability. Additionally, the moderate acidification profile and near-neutral pH of L. fermentum created favorable conditions for postbiotic compound production. These results indicate that L. fermentum derived from P. padus holds considerable promise as a functional adjunct culture in yogurt production. Its postbiotic potential, technological compatibility, and heat-stable bioactivity suggest valuable applications in the development of safe, stable, and health-promoting fermented dairy products. Full article

Functional foods are products that have clinically evidenced health benefits for consumers due to one or more of their ingredients. While research indicates that consumers are highly interested in these products and are often willing to pay premium prices to buy them, stories of market failure are frequent for the specific category. Hence, a critical question is what determines consumers’ willingness to purchase functional food products. A hypothesis confirmed by many studies is that health concerns are positively associated with purchasing intentions. Nevertheless, other factors may also positively or negatively affect consumers’ willingness to buy functional foods. Our work examines this contention by focusing on a novel functional food product: yogurt enriched with sea buckthorn. The product, which is developing in the framework of an ongoing project, is expected to combine the health benefits of yogurt with the medicinal properties of sea buckthorn. Full article

To improve the quality and functional properties of yogurts, a multi-starters co-fermentation system was used during yogurt preparation. In this work, Weissella cibaria G232 (added at 0%, 3%, 5%, and 7%) was involved as a co-fermenter with a traditional starter (Lactobacillus delbrueckii subsp. bulgaricus G119 and Streptococcus thermophilus Q019). The results showed that W. cibaria G232 co-fermentation could shorten the fermentation time and significantly enhance the viable counts of yogurt (p < 0.05). Moreover, the incorporation of W. cibaria G232 improved the water holding ability, viscosity, and texture of yogurt. Notably, the highest levels of firmness, consistency, and cohesiveness of yogurt were observed at the 5% addition level of W. cibaria G232. Furthermore, co-fermentation with W. cibaria G232 significantly enhanced the antioxidant activity of yogurt, as evidenced by increased free radical scavenging capacity and ferric ion reducing antioxidant power (FRAP) value. The intelligent sensory technology and Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) indicated that co-fermentation with W. cibaria G232 and a traditional starter notably altered the accumulation of aldehydes, ketones, and alcohols in yogurt. These findings suggest that co-fermentation of W. cibaria G232 with a traditional starter present the potential for the quality and functionality improvement of yogurt and also lay the foundation for the application of W. cibaria G232. Full article

In pursuing functional foods that promote health, nanoliposomal carriers have been used to enhance the stability and functionality of dairy products such as yogurt, promising therapeutic benefits. This study aimed to evaluate the impact of fucoxanthin-loaded nanoliposomes in yogurt on its antioxidant, physicochemical, and rheological properties under cold storage (21 days). Fucoxanthin-loaded nanoliposomes were prepared using the ultrasonic film dispersion technique and added at concentrations of 0%, 5%, and 10% in the yogurt (Y-C, Y-FXN-5, Y-FXN-10). Homogeneous and uniform nanoliposomes (98.28 nm) were obtained, preserving their integrity and functionality and ensuring the prolonged release and bioavailability of fucoxanthin. Y-FXN-10 maintained the highest antioxidant activity according to the DPPH (52.96%), ABTS (97.97%), and FRAP (3.16 mmol ET/g) methods. This formulation exhibited enhanced erythroprotective potential, inhibiting hemolysis, photohemolysis, and heat-induced hemolysis. However, viscosity and firmness decreased, affecting the texture and appearance. Sensory properties such as the color, flavor, aftertaste, texture, and overall acceptance improved with the 10% fucoxanthin-enriched yogurt formulation. These results suggest that nanoliposomes are suitable for carrying fucoxanthin. Their incorporation into food matrices is critical to developing functional foods. Regulatory approvals and consumer perceptions regarding nanotechnology-based products must be addressed, emphasizing their safety and health benefits. Full article