Search Results (1,138)

There is a growing trend in food fortification to use natural products to improve quality during production and processing. We study the effect of high-intensity ultrasound (HIU), applied at different processing times to fresh raw cow’s milk supplemented with dried plant material (DPM), on the gel fermentation kinetics and the physicochemical profile of yogurt during storage. The results showed a significant reduction in milk fermentation with the application of HIU after inoculation (INOC). The counts of Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus increased with the use of HIU, producing a synergistic effect in the presence of DPM due to the phenolic acids and flavonoids present. Syneresis was reduced and the water holding capacity (WHC) significantly increased in gels obtained with milk to which DPM had been added and which was sonicated after INOC. This led to the formation of a denser and more homogeneous protein network that retained more serum during storage. The luminosity of gels produced with milk sonicated at 40 °C increased, improving their appearance. However, saturation was reduced, shifting the yellow color to a neutral hue. In gels produced with non-sonicated milk, the fat separated, forming a yellow upper layer. HIU applied after INOC in milk to which DPM had been added reduced the milk processing time, producing stable and better-quality yogurts during refrigerated storage. Full article

This study investigated the effect of a concentrated kombucha inoculum and transglutaminase (TG) on the rheological and textural properties of fermented milk products and compared their average production costs to commercial yoghurt. Semi-skimmed milk was used, to which microbial TG was added at a level of 0.02% w/w. The kombucha inoculum, prepared from black tea, was concentrated to 55.6% total solids. Four samples were produced: two with TG and two without. The TG-containing samples showed significantly higher textural properties, including firmness and consistency, than the non-TG samples. They also exhibited the largest hysteresis loop area and the highest yield stress, indicating a stronger gel structure. The Herschel–Bulkley model successfully described the flow behaviour of all samples and confirmed their shear-thinning, non-Newtonian nature. Principal Component Analysis (PCA) showed that both TG addition and inoculum concentration significantly influenced the product properties. TG improved the rheological and textural properties and increased the stability during storage. However, the production costs for TG-treated samples were higher than those for non-TG-treated samples and commercial yoghurt. Nevertheless, the higher costs could be justified by the perceived additional nutritional benefits for consumers. Overall, the results show that the combination of concentrated kombucha inoculum with transglutaminase can improve the structural and rheological quality of fermented dairy products, which is potentially of commercial importance. Full article

Bioactive peptides (BAPs) from dairy products have garnered increasing attention as natural agents with health-promoting properties, including antihypertensive, antioxidant, antimicrobial, immunomodulatory, opioid, and antidiabetic activities. This systematic review synthesizes research published between 2014 and 2024, retrieved from Scopus and PubMed, and selected according to PRISMA guidelines. A total of 192 studies met the inclusion criteria, collectively reporting over 3200 distinct peptides, with antihypertensive sequences, predominantly angiotensin-converting enzyme (ACE) inhibitors, constituting the largest category (n = 1237). β-casein was the principal precursor across bioactivities, followed by αs1-casein, β-lactoglobulin, and α-lactalbumin. Peptides were primarily produced via enzymatic hydrolysis, microbial fermentation, and gastrointestinal digestion, with peptide profiles influenced by the type of milk, microbial strains, and processing conditions. While cow’s milk remained the dominant source, investigations into goat, sheep, camel, buffalo, and donkey milk revealed species-specific biopeptides. Recent advances in proteomics have enhanced peptide identification and bioactivity prediction, enabling the discovery of novel sequences. These findings underscore the significant potential of dairy-derived BAPs as functional food components and nutraceutical ingredients, while highlighting the need for further in vivo validation, bioavailability studies, and broader exploration of underrepresented milk sources. Full article

Serotonin (5-hydroxytryptamine) is a key neurotransmitter involved in gastrointestinal and central nervous system functions. Given that approximately 90% of serotonin is synthesized in the gut, dietary interventions targeting the gut microbiota have emerged as promising strategies to modulate serotonin homeostasis. Kefir, a fermented milk beverage rich in probiotics and bioactive compounds, has been suggested to influence gut–brain axis signaling, yet its effects in the pediatric period remain insufficiently characterized. This study aimed to investigate the impact of kefir supplementation on serotonin biosynthesis, receptor expression, and metabolic pathways in a pediatric rat model, focusing on molecular markers across brain, jejunum, and serum tissues. Sixteen male Wistar rats (four weeks old) were divided into kefir and control groups. The kefir group received daily oral gavage of kefir (1 mL/100 g) for eight weeks, while controls received saline. Gene and protein expression levels of serotonergic markers (5-HT, TPH1, TPH2, SLC6A4, VMAT2, 5-HTR2B, 5-HTR3A, and 5-HTR4) were analyzed using quantitative PCR, ELISA, and Western blotting. Serotonin turnover was assessed via 5-HIAA levels. Kefir supplementation significantly increased 5-HT and TPH1 expression in both brain and jejunum tissues. In the brain, kefir elevated TPH2 and upregulated 5-HTR3A and 5-HTR2B, while reducing 5-HIAA levels, suggesting decreased serotonin degradation. In the jejunum, 5-HTR4 expression was markedly increased. Serum analyses revealed reduced TPH1/TPH2 expression but elevated 5-HTR4 levels, indicating systemic modulation of serotonergic signaling. Kefir exerts multifaceted effects on the serotonergic system in pediatric rats by enhancing serotonin biosynthesis, modulating receptor expression, and reducing serotonin turnover. These findings highlight kefir as a potential psychobiotic capable of influencing the gut–brain axis during early life, with implications for pediatric neurodevelopment and mental health. Further research, including clinical trials, is warranted to confirm its translational potential. Full article

Milk represents not only a source of essential nutrients but also a versatile matrix for the development of functional foods when combined with lactic acid bacteria (LAB) fermentation. While cow milk is the most widely consumed, alternative matrices such as goat and donkey milk possess distinctive compositional features that may influence the bioactivity of fermented products. In this work, fifteen different strains belonging to LAB and bifidobacteria were initially tested for their ability to ferment cow, goat, and donkey milk. Fermented samples showing the best acidification rate were further screened for total phenolic content (TPC), radical scavenging activity (RSA), and effects in human colon epithelial cells and Caco-2 adenocarcinoma cells. The results showed that fermentation modulated TPC in a strain- and matrix-dependent manner, with donkey milk showing the most consistent increases. RSA was significantly enhanced in fermented samples, particularly those inoculated with Lacticaseibacillus casei BGP93 and LC4P1 strains and Limosilactobacillus reuteri ATCC23272. Cell viability assays confirmed the absence of cytotoxicity, and fermented milk extracts reduced ROS under induced oxidative stress. Antimicrobial assay showed that Lactiplantibacillus plantarum LPAL selectively inhibited Listeria monocytogenes, with the strongest effect observed in donkey milk. These findings suggest that LAB-fermented milks from goats and donkeys may represent safe functional foods with improved antioxidant and antimicrobial activities. Full article

Ulcerative colitis (UC) is associated with gut microbiota imbalance, and probiotics may restore gut flora and improve intestinal health. Sea buckthorn, which is rich in antioxidants and anti-inflammatory compounds, may enhance these effects when combined with probiotics. In this study, we incorporated our screened strain Lactiplantibacillus plantarum YHG-87 (L. plantarum YHG-87) into sea buckthorn fermented milk to examine its additional benefits in a dextran sulfate sodium (DSS)-induced UC mouse model. Five groups (n = 6) were included: healthy control, DSS-induced colitis, regular fermented milk, sea buckthorn fermented milk, and sea buckthorn probiotic fermented milk (SC group). Results indicated that SC group significantly alleviated UC symptoms, such as weight loss, bloody stools, and colon shortening (p < 0.05), and these improvements were more pronounced than those observed in the sea buckthorn fermented milk group. Moreover, the SC group exhibited stronger anti-inflammatory and antioxidant effects, including reduced IL-6, increased IL-4 and IL-10, elevated glutathione, and reduced myeloperoxidase and malondialdehyde (p < 0.05). Additionally, the SC intervention led to notable shifts in gut microbial community composition. In conclusion, the addition of L. plantarum YHG-87 to sea buckthorn fermented milk provided enhanced protective effects against UC, suggesting that the combination of bioactive plant components with selected probiotics offers promising potential for UC prevention and therapy. Full article

This study was conducted in two phases: first, to assess the impact of microbial fermentation on enhancing the nutritional quality of fish by-products, and second, to evaluate the effects of replacing fishmeal with these fermented by-products in the diet of Nile tilapia (Oreochromis niloticus) on growth performance, blood parameters, antioxidant indices, immunity, digestive enzyme activity, and carcass composition. In the initial phase, proteolytic activity of five bacterial strains including Bacillus subtilis (ATCC: 6051), B. licheniformis (IBRCM: 10204), Lactiplantibacillus plantarum (PTCCs: 1058 and 1745), and Lactobacillus casei (PTCC: 1608) was evaluated using growth assays in skimmed milk culture media and analyzed using Image-J software. B. licheniformis exhibited the highest proteolytic activity and was selected for fermentation. Resulting hydrolyzed proteins were characterized by peptides with molecular weights below 11 kDa. In the second phase, fishmeal was replaced with fermented by-products at five levels (0 (control), 25, 50, 75, and 100%). Two hundred ten Nile tilapia with an average weight of 2.83 ± 0.05 g were stocked in fifteen 200 L plastic tanks at three replicates, with 14 fish per tank, and fed daily at a rate of 7% of their body weight for 63 days. With increasing levels of fishmeal replacement (25% to 75%), significant improvements (p < 0.05) were observed in final weight gain, body weight gain, specific growth rate, protein production value, and protein efficiency ratio. Additionally, blood plasma concentrations of hormones T₃ and T₄, immunoglobulin level, the activities of complement (ACH₅₀), and antioxidant enzymes (catalase and superoxide dismutase) increased significantly in fish fed the diets with fermented by-products compared to those of the control diet (p < 0.05). The optimal replacement levels for specific growth rate and feed conversion ratio were identified as 86.28% and 83.91%, respectively. Full article

Lactobacilli are important probiotic groups recognized for their numerous health-promoting properties. This study investigated how four probiotic strains, Lacticaseibacillus rhamnosus (Lr), Lactobacillus acidophilus (La), Lactiplantibacillus plantarum (Lp), or Lacticaseibacillus casei (Lc), affected post-acidification, viable cell counts (VCCs), total phenolic and flavonoid contents (TPCs and TFCs, respectively), and antioxidant activity of fermented almond milk (FAM) and its combination with cow’s milk (CM) at different concentrations (75:25, 50:50, and 25:75) during 1, 7, 14, and 21 days of storage. All FAM and its mixture with CM showed significantly greater (p < 0.05) post-acidification than their respective controls throughout storage. Viable cell counts in all samples ranged from 5.9 to 6.8 log cfu/mL, which were higher than those of the controls (3–4 log cfu/mL; p < 0.05). Total phenolic contents in FAM/CM (75:25 and 50:50 and 25:75)-Lc increased more than twofold (95.82 ± 0.003 and 105.71 ± 0.008 and 101.02 ± 0.071 μg GAE/mL; p < 0.05) compared to the controls (19–40 μg GAE/mL) by the end of the third week. Lbs. rhamnosus enhanced (p < 0.05) TFCs in FAM/CM (25:75) after the first day of storage. All lactobacilli strains improved the antioxidant activity in all treated samples during storage. In conclusion, the combination of fermented almond milk with cow’s milk may serve as an excellent carrier for Lbs. rhamnosus, Lab. acidophilus, Lpb. plantarum, and Lbs. casei, which exhibit antioxidant activity. Full article

In light of the exponential rise in feed costs within the livestock sector, the scientific research and valorization of novel agro-industrial by-products have essential strategies in animal nutrition. The overall objective of this study was to characterize and evaluate the inclusion of a novel olive pulp included at 12% of the concentrate on a dry matter basis in the diet of Murciano–Granadina goats to assess its effects on ruminal fermentation, nutrient digestibility, energy and nitrogen metabolism, and milk yield and composition. Two experiments were conducted, taking into account two groups (control group, CTL, and an experimental group) with the inclusion of 12% olive pulp in the concentrate (OPD): one in vivo trial in metabolic cages (n = 10 nulliparous female goats (34.1 ± 0.70 kg) per treatment) was conducted to evaluate digestibility, nitrogen balance, and energetic utilization; and a second on-farm production trial (n = 24 adult dairy goats (53.6 ± 1.14 kg) per treatment). The results showed no significant differences in energy balance or microbial protein synthesis between CTL and OPD (p > 0.05). However, the OPD exhibited higher digestibility of dry matter (71.2 vs. 68.8%; p = 0.028), organic matter (70.8 vs. 68.4%; p = 0.026), and crude fat (85.9 vs. 83.4%; p = 0.024), but lower crude protein digestibility (70.7 vs. 73.4%; p = 0.012) and nitrogen excretion (1.24 vs. 1.44 g/kg^0.75; p < 0.001). Additionally, ruminal butyrate concentrations were higher in OPD goats (13.5 vs. 11.3 mol/100 mol of total short-chain fatty acids; p = 0.020). Although milk yield remained unaffected, the OPD exhibited higher milk protein (4.17 vs. 3.79%; p = 0.036) and conjugated linoleic acid (0.620 vs. 0.400%; p < 0.001) concentrations compared to CTL. These findings demonstrate that the inclusion of 12% of the novel olive pulp in goat concentrate is a viable feeding strategy that maintains productive performance while enhancing the nutritional quality of milk. Full article

With the growing demand for functional dairy products, integrating dual-animal proteins presents a promising strategy to enhance both nutritional value and functional properties. This study aimed to elucidate the impact of egg white supplementation on the stability, physicochemical attributes, sensory quality, and shelf-life of yogurt. Yogurt samples were prepared by fermenting milk supplemented with 0%, 5%, 10%, 15%, 20%, and 25% egg white, and subsequently evaluated for physicochemical parameters, microstructure, rheological behavior, water-holding capacity, and sensory profiles using an electronic nose and electronic tongue. Results showed that 5% egg white significantly improved yogurt stability after one day of refrigeration, whereas 10% supplementation yielded texture comparable to the control but with enhanced protein content, water retention, gel strength, and microstructural uniformity. Over 14 days of cold storage, a gradual decline occurred in physicochemical and structural parameters across all samples; however, flavor profiles remained largely stable, with no adverse effects on sensory quality except for a mild increase in acidity. These findings highlight egg white as a functional ingredient capable of improving yogurt stability and textural quality without compromising flavor, offering new opportunities for the development of high-protein, dual-animal protein fermented dairy products in the functional food industry. Full article

Climate change is intensifying heat stress conditions in livestock systems, posing significant challenges to animal welfare, productivity, and food quality. This study aims to investigate the combined effects of seasonal heat stress and postpartum physiology on the milk fatty acid (FA) profile of Holstein dairy cows in Galicia, Spain. Forty milk samples were collected during winter and summer and at 1 week and 1 month postpartum. Fatty acid composition was analyzed via gas chromatography (GC-FID), and heat stress exposure was quantified using the temperature–humidity index (THI). Results revealed that heat stress significantly altered the milk lipid profile, with increased concentrations of short- and medium-chain fatty acids (SMCFA) such as C10:0 and C14:1 (n-5), and conjugated linoleic acids (CLAs), suggesting enhanced de novo lipogenesis and shifts in rumen fermentation. Conversely, unsaturated long-chain fatty acids (LCFAs), including cis-11 C18:1 and cis-13 C18:1, decreased with lactation progression and thermal exposure. Notably, certain LCFAs remained stable under combined seasonal and physiological stress, indicating potential metabolic regulation. These results show how milk composition is sensitive to environmental stress and emphasize the need for climate-resilient management to protect milk quality under global warming. Full article

Cheese manufacturing generates large volumes of whey with high biochemical and chemical oxygen demand, historically treated as waste. Yet, whey is rich in lactose, proteins, and minerals that can be fractionated and upgraded into foods and bio-based products. During cheese production, 80% to 90% of the total volume is discarded as whey, which can cause severe pollution. However, milk by-products can be a natural source of high-value-added compounds and a cost-effective substrate for microbial growth and metabolites production. The current review focuses on cheese whey as a key milk by-product, highlighting its generation and composition, the challenges associated with its production, methods for fractionating whey to recover bioactive compounds, its applications in functional food development, the barriers to its broader use in the food sector, and its potential as a substrate for producing value-added compounds. Particularly, the focus was on the recent solutions to use cheese whey as a primary material for microbial fermentation and enzymatic processes, producing a diverse range of chemicals and products for applications in the pharmaceutical, food, and biotechnology industries. This review contributes to defining a framework for reducing the environmental impacts of whey through its application in designing foods and generating biomaterials. Full article

Background/Objectives: Within the spectrum of lactic acid bacteria, Lacticaseibacillus casei and Lactobacillus johnsonii are of particular technological and nutritional significance. Protein fortification of fermented dairy systems offers dual benefits: it improves product quality while enhancing probiotic resilience. Supplementary proteins supply bioavailable nitrogen and peptides that stimulate bacterial metabolism and contribute to a viscoelastic gel matrix that buffers cells against gastric acidity and bile salts. The aim of this study was to clarify the functional potential of such formulations by assessing probiotic survival under in vitro digestion simulating oral, gastric, and intestinal phases. Methods: Sheep milk was fermented with L. casei 431 or L. johnsonii LJ in the presence of whey protein isolate (WPI), soy protein isolate (SPI), or pea protein isolate (PPI) at concentrations of 1.5% and 3.0%. Physicochemical parameters (pH, titratable acidity, color, syneresis), organoleptic properties, and microbiological counts were evaluated. The viability of L. casei and L. johnsonii was determined at each digestion stage, and probiotic survival rates were calculated. Results: Samples with L. johnsonii consistently exhibited lower pH values compared to L. casei. Across both bacterial strains, the addition of 1.5% protein isolate more effectively limited syneresis than 3.0%, regardless of protein type. Samples fortified with WPI at 1.5% (JW1.5) and 3.0% (JW3.0) were rated highest by the panel, demonstrating smooth, homogeneous textures without grittiness. The greatest bacterial survival (>70%) was observed in WPI-fortified samples (JW1.5, JW3.0) and in SPI-fortified JS3. Conclusions: Protein isolates of diverse origins are suitable for the enrichment of fermented sheep milk, with 1.5% supplementation proving optimal. Such formulations maintained desirable fermentation dynamics and, in most cases, significantly improved the survival of L. casei and L. johnsonii under simulated gastrointestinal conditions, underscoring their potential in the development of functional probiotic dairy products. Full article

Functional foods are defined as consumables that, in addition to providing essential nutrients, exhibit health-promoting properties when consumed regularly over a long period of time. Globally, there has been great emphasis on their consumption as a cost-effective and safer alternative for the prevention, treatment, and management of various health-related issues, including food allergies. Over the past two decades, the prevalence and severity of clinical manifestations of food allergy (FA) have increased significantly. FA results from the breakdown of immune tolerance. There are different types of functional foods that can be effective in the treatment of FA. Functional foods based on postbiotics that are produced through fermentation include kefir, yogurt, cheese, and fermented milk. This review highlights the potential role of functional foods based on postbiotics in the treatment of FA. Full article

The present study investigates the hypothesis that green plantain peel (GPP) could be used as a functional ingredient to enrich fermented milk, thus improving its nutritional profile and bioactive content. The objective of the present study was to develop a fermented milk product with added GPP and to evaluate its physical–chemical, technological, microbiological, and sensory characteristics, as well as the bioaccessibility of bioactive compounds after in vitro digestion (INFOGEST). The methodological strategy involved the formulation of four treatments: one control (Fermented Milk Control, FMC) and three with different concentrations of cooked plantain peel (5%—FM5, 10%—FM10, and 20%—FM20). The results demonstrated that the incorporation of peel had a significant impact on the technological properties, resulting in increased syneresis and color change. In contrast, pH and acidity were more influenced by storage duration. Lactic acid bacteria demonstrated viability at probiotic concentrations (≥10⁶ CFU/mL) for a duration of up to 11 days. The incorporation of GPP resulted in a substantial increase in the phenolic compound content and antioxidant activity of the product, with the FM20 treatment showing the highest antioxidant activity (DPPH: 1555 ± 16 µmol TE/mL, ABTS: 576 ± 29 µmol TE/mL, FRAP: 2427 ± 58 µmol Fe²⁺/mL) compared to FMC. Sensory analysis revealed that texture and color were the most influential attributes, with formulations FM5 and FM10 being the most accepted, as indicated by an acceptability index above 82%. The simulated in vitro digestion led to an increase in the measurable phenolic content and a corresponding enhancement of antioxidant activity. This suggests that the digestive process enhances the release of these compounds from the food matrix, thereby increasing their bioaccessibility. Full article