Search Results (303)

Cheese ripening is slow and costly, driving interest in accelerating maturation. This study aimed to isolate a safe, efficient adjunct starter from traditional Sichuan yak yoghurt, a niche rich in stress-adapted lactic acid bacteria. From 295 isolates, 15 strains tolerant to high salt, low pH, and low temperature were selected. Using acidification, autolysis, proteolysis, and peptidase activity as indices, principal component analysis identified Limosilactobacillus fermentum 270 as the best candidate. Phenotypic assays showed no haemolysis, gelatin liquefaction, indole production, or amino acid decarboxylase activity. Whole-genome sequencing confirmed species identity and revealed 52 protease/peptidase genes, complete pathways for diacetyl/acetoin biosynthesis and branched-chain amino acid conversion, and no functional biogenic amine synthesis genes. Stress-related genes (F-ATPase, glycine-betaine transport, cold-shock proteins) support cheese adaptability. Antibiotic resistance gene homologs were mainly chromosomal and unlinked to mobile genetic elements; a functional CRISPR-Cas system lowers horizontal transfer risk. The strain was developed as a freeze-dried direct-vat starter (97.3% viability). Orthogonal optimisation of yak Gouda cheese-making defined best conditions: 0.018% adjunct, 45 min acidification, pH 5.8, and 30% curd washing. L. fermentum 270 thus combines proteolytic, flavour-enhancing, genetic safety, and processing traits, offering a promising adjunct for accelerated cheese ripening. Full article

The aim of the research was to assess changes in the bioactive status of organic yoghurts produced in the spring/summer season from Simmental cows’ bulk milk during 28-day refrigerated storage, including whey proteins, lipophilic vitamins, and free fatty acids, and to interpret these changes not only in terms of compositional stability but also regarding their nutritional significance, as evaluated using the IYQ (Index of Yoghurt Quality) for vitamins. Raw milk was found to be a significantly richer source of biologically active compounds compared with milk subjected to heat treatment. During the 28-day refrigerated storage of the yoghurts, unfavourable alterations were observed in the levels of selected bioactive components belonging to both the protein and lipid fractions. A reduction in the concentration of the analyzed proteins and vitamins was observed, ranging from 2% for vitamin D₃ to 38% for lactoferrin, while the content of free fatty acids increased, from 8% for monounsaturated free fatty acids (MUFFAs) to 39% for short-chain free fatty acids (SCFFAs). The most pronounced changes were observed in lactoferrin content (p ≤ 0.01), whereas vitamin D₃ exhibited the highest stability throughout the storage period. The stability of vitamin D₃ was further confirmed using the Index of Yoghurt Quality (IYQ). Despite the significant changes observed in the bioactive profile, the yoghurts retained high sensory quality throughout the entire storage period. This indicates that alterations in bioactive status did not compromise the sensory quality of the product, even after 28 days of storage (i.e., at the end of the shelf life). The obtained results indicate the feasibility of developing organic milk processing directly at the farm level while preserving the nutritional value of the products. The possibility of processing organic milk not only into cheese but also into fermented dairy beverages, particularly yoghurts, is of key importance for farmers aiming to diversify production, increase added value, and improve the economic sustainability of small-scale organic farms. Full article

Background/Objectives: The global population is ageing rapidly, with projections indicating that there will be over two billion individuals aged ≥60 years by 2050. Sarcopenia and frailty are major age-related syndromes associated with loss of muscle mass, reduced strength, and increased vulnerability, for which adequate protein and amino acid intake are key preventive factors. However, nationally representative data on dietary amino acid intakes and sources among older adults are lacking, particularly in Europe. Methods: This study aimed to address this gap by updating the Irish Food Composition Database (IFCD) (2011) with amino acid composition data and estimating amino acid intakes and dietary sources in older adults in Ireland (≥65 years) using data from the National Adult Nutrition Survey (2008–2010; n = 226). Results: Mean total amino acid intake was 76.2 g/day (1.0 g/kg body weight/day). Intakes of all essential amino acids were above the US Institute of Medicine (IOM) recommendations, with no significant differences observed between sexes or age groups (65–74 y, 75+ y). ‘Meat and meat dishes’ were the principal contributors to amino acid intake (28–47%), followed by ‘breads and rolls’, ‘milk and yoghurt’, and ‘fish and fish dishes’. Conclusions: This study provides the first nationally representative estimates of amino acid intakes in older adults in Europe, establishing a baseline for future dietary surveillance and informing protein quality assessment amid dietary transitions toward plant-based foods. Full article

Carrot juice processing generates large amounts of pomace, a fibre-rich by-product with significant valorisation potential. This study explored the feasibility of fermenting carrot by-product with Levilactobacillus brevis AM7 and Leuconostoc pseudomesenteroides DSM20193 to produce exopolysaccharide (EPS)-enriched functional beverages. Beverages were fermented with or without sucrose addition (EPS⁺ and EPS⁻, respectively) and characterized for microbiological, biochemical, rheological, and sensory attributes. Both strains showed robust growth (>8 log cfu/mL) and acidification (final pH below 4.8), comparable to plant-based yoghurt alternatives, with EPS synthesis markedly enhanced in sucrose-supplemented beverages. Leuc. pseudomesenteroides DSM20193 synthesized the highest EPS concentration (16.8 g/100 g dry weight), resulting in a 6-fold viscosity increase compared to EPS⁻ samples, thus improving the adherence to the spoon and preventing syneresis of the beverages. Sensory evaluation revealed that EPS⁺ carrot-based beverages had improved sweetness due to a slight sucrose residue, aroma, and mouthfeel, while maintaining low off-flavours and high colour uniformity. The results highlight carrot by-product as a promising substrate for developing clean-label beverages that are rich in dietary fibres and polyphenols and show antioxidant and potential prebiotic properties through sustainable fermentation processes. Full article

Background/Objectives: This study evaluated whether yoghurt containing Apilactobacillus kunkeei DSM 12361 protects rats against non-alcoholic fatty liver disease (NAFLD). We hypothesized that this fructophilic probiotic, with anti-inflammatory properties, may affect NAFLD progression by improving the gut microbiome, lowering intestinal ethanol production, and modulating inflammatory and metabolic pathways linked to hepatic fat accumulation. Methods: Wister rats were randomized into three groups; rats in the control group (HFrD) were fed a high-fructose (70%) diet while rats in experimental groups were fed the same diet mixed with 10% of yoghurt containing YC-180 starter culture (HFrD-Y) or yoghurt containing YC-180 and Apilactobacillus kunkeei DSM 12361 (HFrD-Y-A). Results: After six weeks of intervention, levels of plasma triglycerides, cholesterol, glucose, liver enzymes (ALT and AST), interleukin (IL)-6, fecal ethanol, Enterobacteriaceae, and hepatic index were significantly increased (p < 0.05) in the HFrD group as compared to rats in both experimental groups. Moreover, plasma levels of liver enzymes, lipid profile, glucose, and IL-6 were significantly lower (p < 0.05) in rats of the HFrD-Y-A group than those in the HFrD-Y group. Furthermore, plasma levels of IL-10 and fecal Lactobacilli and Bifidobacteria were significantly increased (p < 0.05) in the experimental groups when compared to rats in the control group. Conclusions: In sum, the obtained results indicated that yoghurt containing Apilactobacillus kunkeei could decrease the risk of non-alcoholic fatty liver disease (NAFLD) through (a) blocking the inflammation process associated with NAFLD, (b) enhancing the lipid profile, (c) lowering fecal ethanol, and (III) decreasing the levels of fecal Enterobacteriaceae in comparison with levels of fecal Lactobacilli and Bifidobacteria in rats. More research on molecular mechanisms of the potential effects of the Apilactobacillus kunkeei strain against NAFLD is still required. Full article

Background: Ambient yoghurt, also known as room-temperature yoghurt, has gained increasing attention due to its convenience in distribution and consumption without needing cold storage. To ensure extended shelf life, ambient yoghurt normally undergoes an additional heat treatment during manufacturing, the post-fermentation sterilisation process (typically at 65–85 °C), which may induce the formation of fine particle aggregates and result in undesirable textural attributes, particularly graininess. Assessing textural attributes of such products remains a challenge. Methods: By mimicking the oral behaviour of ambient yoghurt, this study uses rheological as well as tribological techniques for objective assessment of the textural sensations of slipperiness and graininess. Various experimental conditions, including the amount of saliva incorporation, sliding speed, and ball-contact and plate-contact lubrication, were examined, and results were analysed against perceived texture by panellists. Main findings: The results indicate that viscosity changes are closely associated with perceived slipperiness under the tested conditions. The friction coefficient obtained from a plate-contact tribometer shows a positive correlation with the sensation of graininess (Pearson’s r was 0.74, p < 0.05, N = 8). It was also observed that a 20% saliva incorporation showed the closest agreement with sensory perception, although this observation should be interpreted cautiously due to the limited sample size. Implications: Results obtained from this work indicate the feasibility of using rheology and tribology techniques for texture prediction in ambient yoghurt. The findings are exploratory in nature, and further studies with larger sample sets are required to validate the proposed approach. The methodology presented here may serve as a reference framework for investigating texture perception in other dairy systems. Full article

This study investigates the use of a homopolysaccharide (HoPS)-producing Latilactobacillus sakei strain for the production of protein-enriched plant-based yoghurt analogues based on coconut milk. Formulations varied in added sucrose (2.5% or 5.0% w/w), pea protein isolate (PPI; 0–5.0% w/w), and tapioca starch (0%, 1.5% w/w), and were fermented with either a HoPS-producing strain (L. sakei 1.411), or a non-exopolysaccharide (EPS)-producing control strain (L. sakei 1.2037) with very similar acidification kinetics. Microbial growth and pH were monitored, HoPS content was determined via HPLC, and both firmness and syneresis were assessed during 5 days of storage at 4 °C. EPS yields were significantly higher (p < 0.05) in samples with 5.0% w/w added sucrose compared to those with 2.5% w/w. Fermentation with L. sakei 1.411 generally resulted in firmer gels (p < 0.05) and reduced syneresis (p < 0.05) compared to L. sakei 1.2307 and the enhanced viscosity (sample thickness) was also observed in a sensory analysis. Samples containing starch and 5.0% w/w PPI showed the highest firmness-related values. These findings demonstrate the potential of in situ HoPS production to improve the texture and stability of protein-enriched coconut-based yoghurt analogues. It highlights the importance of matrix formulation, strain selection and process control, which all contribute to the final product quality. Full article

What people consume for breakfast and why they do so have not been widely studied, especially in developing-economy countries. This study aimed to determine the breakfast food habits and their drivers of adults in South Africa, a multiethnic middle-income country. An online cross-sectional survey was conducted among 1000 representative consumers of moderate to higher living standard (Living Standard Measure [LSM] range ≥ 5). Data from 842 respondents (mean age 41 years, 51.7% females and 48.3% males) was analyzed. Of 21 different food types in descending order, the most frequently consumed were bread, ready-to-eat (RTE) cereals, fruits/nuts, high-fibre cereal, yoghurt, and leftovers, all consumed weekly by 42–65% of respondents. Principal component analysis revealed that three components had eigenvalues > 1 characterized as “On-the-go”, “Traditional”, and “Ready-to-eat and functional cereals”. They explained 49% of the data. Decision tree analysis revealed that, for example, Black respondents were more likely to consume foods in the “traditional” category. Quick-and-easy options, notably bread, RTE cereals, fruits/nuts, and leftovers, were dominant, especially among lower LSM respondents. Tasty and filling, and value for money, as exemplified by leftovers and vetkoek (fried dough), were important considerations, particularly among these respondents. These drivers can lead to unhealthy choices, a major concern in South Africa with its high level of diet-related diseases. This study, however, indicates that South African consumers, irrespective of age, ethnicity, and living standard, rated healthfulness and nutritional value highly as a benefit, the highest for choosing 13 of the 21 foods. Additionally, aspects of wellness, e.g., feeling energized/recharged, rated very highly. Thus, it is concluded that the opportunity exists to support consumer needs of nutrition and wellness together with affordability, taste, and satiety. Full article

This study investigated the effects of various concentrations of coriander seed powder (CSP) (0.1%, 0.3%, and 0.5%) on the fermentation performance, whey precipitation rate, texture, rheological properties, microstructure, and sensory characteristics of spoonable yoghurt stored at 4 °C for 21 days. The aim was to evaluate the impact of CSP on spoonable yoghurt quality and its health-promoting properties. The results revealed that the addition of CSP led to a significant decrease in pH and an increase in titratable acidity. Furthermore, the whey precipitation rate in the CSP-enriched yogurt sample was clearly lower than that of the control group (p < 0.05). The syneresis of the yogurt sample with 0.3% CSP decreased by 21.14 on the 21st day, compared to the control group (49.64%) (p < 0.05). This was accompanied by a reduction in apparent viscosity and an increase in the viscoelastic modulus. Meanwhile, the texture of the yogurt sample remains more stable, with the best sensory acceptance in the yogurt sample containing 0.3% CSP. As the concentration of coriander seed powder level increased, antioxidant activity, digestibility, and small molecule phenolic level of the yogurt samples obviously improved (p < 0.05). Yogurt with 0.3% CSP still showed significantly enhanced antioxidant capacity during the 21-day storage period. The DPPH-radical scavenging rate increased by 5.22% compared to the control group (p < 0.05). Similarly, the ABTS+ clearance activity increased by 12.52% (47.06% compared to 34.54% in the control group, p < 0.05). In the 0.3% CSP yogurt group, the total phenolic content reached 5.33 mg GAE/100 g, an increase of 1.85 compared to the control sample (3.48 mg GAE/100 g) (p < 0.05). The in vitro protein digestibility of the yogurt samples containing 0.3% CSP clearly increased by 12.65% (p < 0.05). In summary, the yogurt sample supplemented with 0.3% CSP demonstrated optimal sensory quality characteristics. Coriander seed powder may be used as a beneficial ingredient containing rich active substances to enhance the quality of spoonable yoghurt products. Full article

This study evaluated the effects of different concentrations (0.25%, 0.5%, and 1.0% w/w) of highly purified (90%) β-glucan (scleroglucan—SCGL) produced by Sclerotium rolfsii on the physicochemical, rheological, microbiological, and sensory properties of full-fat yoghurt (3.2% fat). The fermentation dynamics, titratable acidity, apparent viscosity, hardness, adhesiveness, colour, microstructure, and volatile compound profiles of the studied yoghurts were analysed. The addition of SCGL increased gel hardness and viscosity, while preserving its pseudoplastic flow behaviour (n = 0.10–0.15). In samples containing 1.0% SCGL, yield stress (τ₀) increased from 0 Pa in the control to 739 Pa after 28 days of storage, pointing to the formation of a dense protein–polysaccharide network. The analysed polysaccharide slowed down lactose hydrolysis and acidification, but increased the counts of Streptococcus thermophilus (7.7 log CFU·g⁻¹) compared to the control (5.8 log CFU·g⁻¹). The volatile compound analysis showed increased acetaldehyde (5.6 mg·L⁻¹) and diacetyl (5.0 mg·L⁻¹) levels and reduced acetoin (~1.0 mg·L⁻¹) concentration, which enhanced the intensity of the buttery aroma. The sensory evaluation revealed that yoghurts containing 1% SCGL had the most desirable smooth consistency and a balanced, fresh aroma, whereas yoghurts with lower SCGL concentrations (0.25–0.5%) were characterised by a mealy mouthfeel and thinner consistency. Scleroglucan proved to be an effective natural stabiliser and flavour modulator that improved the structure, stability, and sensory quality of full-fat yoghurts. Full article

Background/objectives: Given the suboptimal vitamin D intake and status among the United Kingdom population, the Scientific Advisory Committee on Nutrition is seeking suitable food vehicles for vitamin D fortification. Thus, this study aimed to examine the efficacy of vitamin D-fortified dairy products in improving serum 25-hydroxyvitamin D [25(OH)D] concentration using data from randomised controlled trials (RCTs). Methods: PubMed, Embase, and Web of Science were searched from inception until October 2024. Studies were included if they were RCTs with intervention groups administered vitamin D-fortified dairy products and control groups administered unfortified dairy products, as well as examining the effects on serum 25(OH)D concentration. Results: There were 35 RCTs eligible for inclusion, involving 4965 participants (intervention: 2526; control: 2439). The results showed that serum 25(OH)D concentrations were significantly increased by vitamin D₃-fortified milk/milk powder (n = 15, mean difference (MD): 18.31 nmol/L, 95% confidence interval (CI): 13.30–23.33 nmol/L, I² = 95%), vitamin D₃-fortified yoghurt/yoghurt drinks (n = 11, MD: 26.22 nmol/L, 95% CI: 18.67–33.77 nmol/L, I² = 97%), vitamin D₂-fortified milk/milk powder (n = 3, MD: 11.61 nmol/L, 95% CI: 9.31–13.91 nmol/L, I² = 0%), vitamin D-fortified (type not specified) milk/milk powder (n = 8, MD: 13.59 nmol/L, 95% CI: 8.54–18.64, I² = 98%), and vitamin D-fortified (type not specified) yoghurt/yoghurt drinks (n = 4, MD: 27.74 nmol/L, 95% CI: 16.83–38.64 nmol/L, I² = 91%), but insignificantly increased by vitamin D₃-fortified cheese (n = 5, MD: 16.78 nmol/L, 95% CI: −3.61–37.16, I² = 99%). However, the results of vitamin D₃-fortified cheese became significant when leave-one-out analysis was performed by omitting one RCT (MD: 24.13 nmol/L, 95% CI: 4.69–43.58, I² = 90%). Conclusions: These findings provide evidence that vitamin D-fortified dairy products have the potential to improve serum 25(OH)D concentrations in populations. Full article

There is no clear consensus regarding which Front-of-Pack (FoP) label is more effective in promoting healthier food choices. This study explored consumers’ healthiness perception (HP) and willingness to buy (WTB) foods labelled with two different FoP labels: Nutri-Score (NS) and NutrInform Battery (NIB). The role of individual characteristics, such as sociodemographic variables, purchasing behaviors, orthorexia nervosa tendency, and cognitive abilities, in predicting consumers’ responses was also examined. Through an online survey, Italian consumers (n = 436; 71% female; average age: 38.9 ± 14.7) evaluated the HP and WTB of yoghurt and fruit jam, with three different nutritional qualities (high, medium, low) and labelled with both NS and NIB. The results showed significant differences between NS and NIB, with effects varying across product categories and nutritional profiles. Age, frequency of nutrition label reading, and role in buying decisions emerged as significant predictors of consumers’ responses, particularly for products with high nutritional quality. Conversely, orthorexia nervosa tendencies and cognitive abilities did not significantly predict differences in HP and WTB between FoP labels. These findings expand the understanding of the complexity involved in selecting an appropriate FoP labelling system and offer valuable insights to effectively guide healthier food choices while accommodating diverse consumers’ profiles. Full article

The sustainable valorisation of agro-industrial by-products offers a promising pathway to address global protein demand while supporting circular food systems. This study explored the biotechnological potential of pumpkin (Cucurbita pepo), sunflower (Helianthus annuus), and walnut (Juglans regia L.) oilseed cakes as substrates for developing vegan yoghurt-like fermented beverages. Each formulation was fermented with Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, and comprehensively evaluated for composition, functionality, sensory properties, and bioactivity. The oilseed-based beverages exhibited protein levels between 3.7–4.6%, fibre content up to 1.9%, and reduced syneresis (14–18%) compared with the commercial almond-based product (21.5%). The walnut-based variant (WOCY) showed the highest total polyphenol content (1108.97 mg GAE kg⁻¹) and antioxidant activity (412.54 mg Trolox kg⁻¹ DPPH; 51.5 mg TE g⁻¹ DW ABTS), surpassing both the almond-based vegan yoghurt (238.82 mg GAE kg⁻¹) and dairy reference (96.10 mg GAE kg⁻¹). Preliminary sensory profiling through the Check-All-That-Apply (CATA) method indicated that pumpkin- and walnut-based samples were most associated with “creamy texture,” “nutty aroma,” and “very pleasant” descriptors, achieving acceptance comparable to or higher than conventional yoghurts. Microbiological analyses confirmed product safety and high viable cell counts (<10⁸ CFU mL⁻¹) after 14 days of storage. Oilseed cakes serve as efficient substrates for producing nutrient-dense, antioxidant-rich, and sensorially appealing plant-based fermented beverages, supporting functional food innovation and promoting circular bioeconomy through the sustainable valorisation of agro-industrial by-products. Full article

This study investigated the effects of direct vat set commercial yoghurt starter (B) and yeast starter (Y) on the quality of fermented large yellow croaker surimi balls, with natural fermentation (CTR) as a control. Surimi products were inoculated and fermented at 25 °C for 4 h, then analyzed for physicochemical, sensory, and oxidative properties. Yoghurt starter significantly inhibited protein oxidation, as indicated by the highest sulfhydryl content (9.10 nmol/mg protein, p < 0.05), improved textural properties (hardness was 28% higher than CTR, p < 0.05), and promoted a balanced flavor profile, accompanied by the highest equivalent umami concentration (1.66%, p < 0.05). However, B also caused the greatest MDA accumulation (1.49 mg/kg, p < 0.05), reflecting enhanced lipid oxidation. By comparison, Y enhanced umami primarily through significant enrichment of aspartic acid (53.88 mg/100 g, p < 0.05) and accelerated nucleotide degradation, resulting in the highest AMP and hypoxanthine levels (p < 0.05). These advantages were offset by severe protein carbonylation (54.32 nmol/mg protein, p < 0.05) and evident color deterioration. Sensory analysis revealed no significant difference between B and CTR (p > 0.05), whereas Y received significantly lower acceptance scores (p < 0.05) due to impaired color and taste. These findings suggest that B is a promising starter for improving texture and flavor in fermented surimi balls, while Y, despite enhancing umami and controlling lipid oxidation, negatively affects color, texture, and protein stability. 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