Search Results (142)

Podliveni cheese is a traditional fresh cheese produced in Serbia, typically made from fresh cow’s milk. Donkey milk is recognized for its nutritional benefits, particularly its hypoallergenic properties; however, its use in cheese production is partially limited due to its specific protein composition and low casein content. In addition, information in the scientific literature regarding its application in cheese production remains limited. In this study, Podliveni cheese was produced from raw cow’s milk, while in a second experimental group, 30% milk from autochthonous Balkan and Banat donkey breeds was added to obtain a value-added Podliveni cheese. The selected proportion (30%) was based on previous studies using lower inclusion levels (10% and 20%), which demonstrated measurable but limited effects on cheese properties. The technological production process was identical in both groups and is described for each type of cheese. Microbiological parameters analyzed included total lactic acid bacteria (LAB), Enterobacteriaceae, Escherichia coli, coagulase-positive staphylococci (CPS), Salmonella spp., and Listeria monocytogenes. Sensory analysis was conducted using a five-point hedonic scale with a panel of 21 participants (male and female, aged 20–60 years). The following chemical composition parameters were also evaluated: dry matter, fat content, fat in dry matter, fat-free dry matter, protein, ash, pH, and salt. The content of essential minerals and trace elements was determined, including Ca, P, Na, K, Mg, Zn, Cu, Fe, and the Ca/P ratio. The addition of donkey milk significantly affected curd formation, which required six times longer compared to cheese produced exclusively from raw cow’s milk. Furthermore, the inclusion of donkey milk reduced cheese yield and resulted in increased whey separation during storage, indicating reduced water-holding capacity. No statistically significant differences were observed in microbiological parameters, and pathogenic bacteria (Salmonella spp. and Listeria monocytogenes) were not detected in either cheese. No significant differences were observed in most sensory attributes, except for texture. Conversely, the inclusion of donkey milk significantly affected the majority of chemical parameters and the mineral composition of the cheese. The addition of donkey milk resulted in a significant decrease (p < 0.05) in fat, fat in dry matter, fat-free dry matter, Ca, P, K, Zn, Cu content and the Ca/P ratio, while a significant increase (p < 0.05) was observed in dry matter, protein, salt, Na, Mg, and Fe content. The incorporation of donkey milk represents an innovative approach that expands the range of traditional cheeses without compromising the absence of tested pathogenic bacteria and preserving traditional production practices, simultaneously offering new value-added products. Further research is required to better understand the health benefits associated with the inclusion of donkey milk in cheese production. This study contributes to expanding knowledge on the use of donkey milk and supports the conservation of autochthonous breeds and the improvement of human health. Full article

Somatic cell count (SCC) in milk is widely used as an indicator of intramammary infections in dairy sheep and is routinely monitored by the dairy industry as a marker of milk quality. This study aimed to evaluate the effect of SCC levels on milk production, composition, colour, coagulation properties, and cheese-making ability in Manchega dairy sheep. A total of 752 individual milk samples were analysed. To normalise SCC distribution, the somatic cell score (SCS) was calculated and samples were classified into SCS classes. Increasing SCS significantly reduced daily milk yield and lactose content, increased milk pH, and decreased lightness (L*). Higher SCS was also associated with impaired coagulation properties, including longer rennet clotting time (RCT) and curd firming rate (k₂₀), as well as reduced curd firmness (A₃₀, A₆₀). Similar effects were observed for modelled coagulation parameters, with delayed RCTeq and reduced kCF and CFp. Regarding cheese-making ability, SCS significantly affected curd humidity and protein recovery, whereas no significant effects were detected for dry curd yield or fat recovery. Overall, elevated somatic cell counts were associated with a reduction in the technological quality of Manchega sheep milk, particularly affecting coagulation behaviour and curd characteristics. These results underline the importance of controlling SCC levels in dairy sheep systems for both udder health monitoring and maintaining milk suitability for cheese-making. Full article

Plant-derived coagulants are increasingly explored as alternatives to animal rennet. This study provides the first evaluation of the coagulation kinetics and technological properties of Onopordum platylepis Murb. in ewe’s milk. Response surface methodology was applied to optimize temperature (30, 33, and 36 °C), pH (5.5, 6.0, and 6.5), and calcium chloride concentration (2, 4, and 6 mM). The optimal conditions for minimizing milk-clotting time were 36 °C, pH 5.5, and 6 mM CaCl₂. Under standardized activity (50 IMCU/L), the Rheological properties of gels produced by Onopordum platylepis were compared with Cynara cardunculus, Cynara humilis, animal rennet, a commercial plant coagulant, and fermentation-produced chymosin. Onopordum platylepis showed slower curd-firming rates than animal rennet and Cynara cardunculus, but similar behavior to Cynara humilis. Gels produced with Onopordum platylepis exhibited firmness comparable to commercial plant coagulants. The water-holding capacity was similar to other coagulants, though protein losses were higher for Onopordum platylepis, Cynara humilis, and Cynara cardunculus than animal rennet. Overall, Onopordum platylepis demonstrates potential for ewe’s milk cheese production, in which highly proteolytic coagulants are used. Full article

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 this study was to assess the influence of milk’s rennet coagulation properties (RCPs) on cheese yield and cheese-making losses in the production of Parmigiano Reggiano PDO cheese. Higher contents of citric acid (181.10 vs. 172.13 vs. 166.47 mg/100 g) and phosphorus (95.02 vs. 91.14 vs. 88.78 mg/100 g) in milk with optimal and sub-optimal RCPs, compared to milk with poor RCPs, respectively, positively affect the acidity of the milk, lowering the pH values (6.68 vs. 6.70 vs. 6.72, respectively), which results in a faster reaction between chymosin and casein and consequently a reduced time of milk coagulation. The lower values of curd firming time and the higher values of curd firmness, strength to cut (68.97 vs. 64.43 vs. 44.38 g), and strength to compression (31.48 vs. 30.49 vs. 25.70 g) for milk with optimal and sub-optimal coagulation, compared to milk with poor coagulation, result in a higher stress resistance across the technological steps of the cheese-making process, leading to lower fat losses (14.23 vs. 15.48 vs. 16.72%) in the whey and a higher cheese yield (8.79 vs. 8.56 vs. 8.08 kg/100 kg). Full article

Kargı Tulum cheese differs from other Tulum cheeses with its unique production and ripening method. No systematic study has yet explored the change in the volatile compounds and fatty acids during the ripening process of Kargı Tulum cheese. The objective of this study was to monitor the change in the fatty acids and volatile compounds of Kargı Tulum cheese at different time points during the production and ripening stages. Fatty acid profile, lipid quality parameters and volatile compound profiles were determined. A principal component analysis (PCA) was performed to determine how the volatile profiles differed across production and ripening stages. During the ripening, short- and medium-chain fatty acids (FAs) increased with notably high levels of butyric acid. Lipid quality parameters, including total saturated FAs (SFAs), atherogenicity index (AI), and thrombogenicity index (TI), remained unchanged throughout ripening. A total of 62 volatile compounds (VOC) were detected. Esters and ketones were the most abundant groups in fresh curds, while carboxylic acids became the dominant group by the end of the ripening process. The total concentration of most VOC increased over time. Butyric acid, hexanoic acid, ethyl hexanoate and acetic acid were the dominant compounds contributing the flavor of the Kargı Tulum cheese. This study presents data on what flavor compounds form and how they change during ripening and can be useful for comparative purposes in future studies on ripened raw milk cheeses. Full article

An elevated somatic cell count (SCC) affects the physicochemical characteristics of milk, altering its renneting ability and ultimately impacting the yield and quality of the cheese produced. This study aims to analyse the variations in the composition of Latvian goat milk and its technological properties in relation to SCC. Individual goat milk samples (n = 240) were collected from one of the largest goat farms in Latvia during 2019 and 2020. Latvian, Saanen, and cross-breed goat milk samples from different lactations were tested for their chemical composition (fat, protein, lactose, dry matter, and SCC), fat-to-protein ratio, freezing point, and curd firmness. Samples were collected during different lactation periods in order to analyse the seasonal effect on milk quality. The results demonstrated that milk samples from goats with lower SCCs (Group I) exhibited the highest fat (3.34%), lactose (4.56%), and dry matter (11.28%) concentrations and fat-to-protein ratios (1.02). Curd firmness decreased progressively from Group I to Group IV, fluctuating between Latvian Native (1.96–1.47 N), Saanen (1.91–1.59 N), and cross-breed (1.66–1.58 N) goat milk samples. A significantly lower (p = 0.030) curd firmness (1.56 N) was determined in the Group IV goat milk samples. Seasonal fluctuations in milk composition were observed in relation to curd firmness, which peaked in late lactation milk (3.85 N), although minor fluctuations were observed in protein concentrations (3.23% to 3.30%) across the sampling periods (2019 and 2020). These findings highlight the necessity of SCC monitoring in Latvian goat milk to ensure appropriate quality for milk processing. Full article

Background/Objectives: Diet and physical activity are key lifestyle behaviours associated with sleep quality, yet their combined and sex-specific associations remain insufficiently understood. This study examined the associations between dietary behaviours and sleep quality among university students and assessed whether physical activity formed part of an indirect statistical association between these variables, with sex considered as a moderator. Methods: A cross-sectional study was conducted among 418 students (199 males, 219 females) from the Wroclaw University of Health and Sport Sciences. Body height and body mass were measured using standard anthropometric procedures. Sleep quality (SQ) was registered with the Pittsburgh Sleep Quality Index (PSQI), dietary habits were assessed with the Questionnaire of Eating Behaviours (QEB) and physical activity (PA) was assessed with the International Physical Activity Questionnaire (IPAQ). Data-driven feature-selection methods were applied to identify dietary behaviours associated with sleep quality, which were combined into a Synthetic Dietary Behaviour Index (SDBI). A moderated mediation model, adjusted for body mass index (BMI), was then used to examine the statistical associations between dietary behaviours, physical activity, sleep quality, and sex. Sleep quality was modelled as a continuous PSQI score in mediation analyses, while the dichotomised PSQI category was used only for feature selection. Results: Machine-learning feature selection identified nine dietary behaviours statistically associated with sleep quality. Unfavourable behaviours—fast food, fried meals, sweetened beverages, energy drinks and alcohol—were linked to poorer sleep, whereas vegetables, curd cheese and wholegrain bread were associated with better sleep. Poor sleep was more prevalent among females (45.2% vs. 14.6%, χ² (1) = 65.4, p < 0.001). The mediation model indicated that physical activity formed part of a statistically significant but modest indirect association between dietary behaviour and sleep quality, with sex moderating the IPAQ → PSQI path (β = −0.45, p = 0.006). Indirect associations were significant for both sexes but stronger among females (males: β = 0.032, p = 0.021; females: β = 0.102, p = 0.004). Conclusions: Unfavourable dietary patterns and lower physical activity were statistically associated with poorer sleep quality, with a stronger indirect statistical effect observed among females. These findings support the relevance of integrated, sex-sensitive lifestyle approaches addressing both dietary behaviours and physical activity, while acknowledging the cross-sectional nature of the data. Full article

Cheese consumption is steadily increasing worldwide, with a growing interest in cheese enriched with bioactive substances, including antioxidants. This study investigated the impact of adding blackcurrant wine to the curd (IC), enriching the curd with blackcurrant wine by soaking and ripening in salted blackcurrant wine (IOC), and cheese soaked and ripened in blackcurrant wine with 5% (w/w) NaCl (OC). The curd and added wine weight ratio (1.5:1, 3:1) effects were also studied. Physicochemical (dry matter, polyphenol content, antioxidant activity, radical-scavenging activity, anthocyanin content like delphinidin-3-rutoside and cyanidin-3-rutoside, ethanol content), microbiological, and sensory properties of the cheeses were evaluated. The results indicated that a week of soaking is sufficient to achieve the maximum antioxidant capacity and polyphenol content of the cheese. From a technological and sensory point of view, a 1.5:1 ratio of blackcurrant wine to curd was better. The maximum transfer rate of delphinidin-3-rutoside from wine was the most pronounced in IOC samples (20.44%). Blackcurrant wine inhibited the growth of lactic acid bacteria, and a longer soaking time can hinder the ripening process of cheese. During tasting, among the treated cheese, IC samples received the highest average acceptance scores for appearance, texture, creaminess, flavor, saltiness, bitterness, freshness and overall impressions. Full article

Lactic acid bacteria (LAB) play a crucial role in acid-curd cheese production by driving milk protein coagulation and forming metabolites that determine texture, safety, and flavor. This study investigated the effect of enzymatic lactose hydrolysis using β-D-galactosidase (Maxilact LX5000) on the quality of full-fat curd cheeses (16.5% and 20.8% dry matter) produced without whey separation. Cheeses were manufactured with or without prior lactose hydrolysis, inoculated with a mesophilic Flora Danica starter culture, and stored for 28 days at 4 °C. Chemical composition, sugar profile (HPLC), pH, LAB viability, textural properties (hardness, adhesiveness, and water-holding capacity), and sensory attributes were determined. Lactose hydrolysis completely eliminated lactose and increased glucose and galactose concentrations, without significant changes in protein, fat, or pH level. In our data, lactose was undetectable in hydrolyzed samples across storage, glucose/galactose exhibited only minor fluctuations, and LAB counts and pH remained stable, indicating a largely stable sugar profile and limited microbial activity under refrigeration. Hydrolyzed samples showed improved texture, especially higher hardness and moisture retention in low-dry-matter variants, while sensory characteristics were comparable to the control and free from excessive sweetness. These results demonstrate that enzymatic lactose hydrolysis is an effective tool for producing lactose-free curd cheese without compromising quality. This process can be recommended for sustainable whey-free cheese manufacture aimed at lactose-intolerant consumers. Full article

Consumer interest in vegetarian, ethical, and clean-label foods is reviving the use of plant-derived milk coagulants. Cardosins from Cynara cardunculus (“thistle”) are aspartic proteases with strong clotting activity, yet their technological impact in cheese remains under-explored. This study compared a commercial thistle extract (PC) with traditional bovine rennet rich in chymosin (AC) during manufacture and 60-day ripening of Caciotta cheese. Classical compositional assays (ripening index, texture profile, color, solubility) were integrated with scanning electron microscopy, three-dimensional surface reconstruction, and descriptive sensory analysis. AC cheeses displayed slower but sustained proteolysis, yielding a higher and more linear ripening index, softer body, greater solubility, and brighter, more yellow appearance. Imaging revealed a continuous protein matrix with uniformly distributed, larger pores, consistent with a dairy-like sensory profile dominated by milky and umami notes. Conversely, PC cheeses underwent rapid early proteolysis that plateaued, producing firmer, chewier curds with lower solubility and darker color. Micrographs showed a fragmented matrix with smaller, heterogeneous pores; sensory evaluation highlighted vegetal, bitter, and astringent attributes. The data demonstrate that thistle coagulant can successfully replace animal rennet but generates cheeses with distinct structural and sensory fingerprints. The optimization of process parameters is therefore required when targeting specific product styles. Full article

Biogenic amines (BAs) are frequently detected in seafood products, wines, and fermented foods, and they pose potential risks to human health. The current study analyzed the concentrations of five common BAs in seafood, fermented food, and complementary food for infants and children (fish sausage, canned complementary food for infants containing fish and shrimp ingredients, and fish floss) in China and estimated the acute health risks of histamine (HIS) from fermented foods in Chinese consumers. Among all the samples analyzed, HIS exhibited the highest detection rate (51.9%), followed by PUT (50.1%), and the detection rate of TRY (12.5%) was the lowest. The total average concentration of the five BAs across major food categories revealed that fermented bean curd had the highest total concentration of BAs (816.8 mg/kg), followed by shrimp (383.2 mg/kg) and cheese (328.0 mg/kg). In contrast, samples of complementary food for infants and children contained the lowest concentrations of BAs; the total average concentration of the five BAs was 12.0 mg/kg. The point assessment results showed that acute dietary exposure to HIS was highest from cheese (76.2 mg/d), followed by fermented bean products (74.5 mg/d). Furthermore, the probability assessment indicated that the probability of acute health risks from exposure to HIS was 0.44% for fermented bean product consumers and 0.014% for cheese consumers, respectively. Thus, for the general consumer, the probability of acute health risks caused by HIS in seafood and fermented foods is low. However, individuals with high consumption of cheese and fermented bean products may need to be concerned. Full article

The assessment of milk coagulation properties (MCPs) is crucial for enhancing goat cheese production and quality. In this study, 501 bulk goat milk samples were collected from various farms to evaluate the MCPs. Traditionally, cheesemaking aptitude is evaluated using lactodynamographic analysis, a reliable but time-consuming laboratory method. Mid-infrared spectroscopy (MIRS) offers a promising alternative for the large-scale prediction of goat milk’s technological traits. Reference MCP measurements were paired with mid-infrared spectra, and prediction models were developed using partial least squares regression, with accuracy evaluated through cross- and external validation. The ability of MIRS to classify milk samples by coagulation aptitude was evaluated using partial least squares discriminant analysis. Only the model for rennet coagulation time obtained sufficient accuracy to be applied for screening (R²_CrV = 0.68; R²_Ext = 0.66; RPD = 2.05). Lower performance was observed for curd-firming time (R²_CrV = 0.33; R²_Ext = 0.27; RPD = 1.42) and curd firmness (R²_CrV = 0.55; R²_Ext = 0.43; RPD = 1.35). Classification of high coagulation aptitude achieved balanced accuracy values of 0.81 (calibration) and 0.74 (validation). With further model refinement and larger calibration datasets, MIRS may become a resource for the dairy-goat sector to monitor and improve milk suitability for cheesemaking. Full article

A comprehensive characterization of two pressed-curd cheeses produced from ewe’s milk using enzymatic coagulation—Manchego cheese (with Protected Designation of Origin, PDO) and Castellano cheese (with Protected Geographical Indication, PGI)—was performed throughout the manufacturing process (industrial or traditional) and ripening stages (2, 9, 30, 90, and 180 days). Proton high-resolution magic angle spinning nuclear magnetic resonance (¹H HRMAS NMR) spectroscopy, combined with Principal Component Analysis (PCA) and cluster analysis, was applied to intact cheese samples. The combination of this spectroscopic technique with chemometric methods allows for the characterization of each type of sheep milk cheese according to its geographical origin and production method (artisanal or industrial), as well as the estimation of ripening time. The results demonstrate that HRMAS NMR spectroscopy enables the rapid and direct analysis of cheese samples, providing a comprehensive profile of their metabolites—a metabolic ‘fingerprint’. Full article

Consumer demand for dairy products like cheese and curds has resulted in a rise in whey production, which has caused significant waste and environmental issues. For this reason, improving the functional characteristics of whey proteins and their usage value are essential. In this study, camel whey protein–galactose conjugates (CWP-Gal) and camel whey protein–glucose conjugates (CWP-Glu) were prepared through the Maillard reaction, and their structural and functional properties were characterized. Improvements in solubility of 14.90% and 8.17%, emulsification activity of 15.53% and 13.64%, and foaming capacity of 113.95% and 106.03% were demonstrated by CWP-Gal and CWP-Glu in comparison to camel whey protein (CWP). Circular dichroism analysis revealed secondary structure alterations in CWP-Gal and CWP-Glu compared to CWP. SDS-PAGE, FT-IR, and intrinsic fluorescence spectroscopy all verified that sugar molecules and proteins were covalently conjugated. SEM analysis revealed that the conjugates had a more sparsely packed microstructure. The results demonstrate that CWP-Gal exhibits enhanced structural stability and superior functional properties, providing a scientific basis for its potential utilization in the food industry. Full article