Microbiological and Physicochemical Evaluation of Hydroxypropyl Methylcellulose (HPMC) and Propolis Film Coatings for Cheese Preservation.

Dairy products are highly susceptible to contamination from microorganisms. This study aimed to evaluate the efficacy of hydroxypropyl methylcellulose (HPMC) and propolis film as protective coatings for cheese. For this, microbiological analyses were carried out over the cheese' ripening period, focusing on total mesophilic bacteria, yeasts and moulds, lactic acid bacteria, total coliforms, Escherichia coli, and Enterobacteriaceae. Physicochemical parameters (pH, water activity, colour, phenolic compounds content) were also evaluated. The statistical analysis (conducted using ANOVA and PERMANOVA) showed a significant interaction term between the HPMC film and propolis (factor 1) and storage days (factor 2) with regard to the dependent variables: microbiological and physicochemical parameters. A high level of microbial contamination was identified at the baseline. However, the propolis films were able to reduce the microbial count. Physicochemical parameters also varied with storage time, with no significant differences found for propolis-containing films. Overall, the addition of propolis to the film influenced the cheeses' colour and the quantification of phenolic compounds. Regarding phenolic compounds, their loss was verified during storage, and was more pronounced in films with a higher percentage of propolis. The study also showed that, of the three groups of phenolic compounds (hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids), hydroxycinnamic acids showed the most significant losses. Overall, this study reveals the potential of using HPMC/propolis films as a coating for cheese in terms of microbiological control and the preservation of physicochemical properties.

Autochthonous cultures to improve the quality of PGI Castellano cheese: Impact on proteolysis, microstructure and texture during ripening.

The aim of this research was to find out the effect of different combinations of starter and non-starter cultures on the proteolysis of Castellano cheese during ripening. Four cheese batches were prepared, each containing autochthonous lactobacilli and or Leuconostoc, and were compared with each other and with a control batch, that used only a commercial starter. To achieve this, nitrogen fractions (pH 4.4-soluble nitrogen and 12 % trichloroacetic acid soluble nitrogen, polypeptide nitrogen and casein nitrogen), levels of free amino acids and biogenic amines were assessed. Texture and microstructure of cheeses were also evaluated. Significant differences in nitrogen fractions were observed between batches at different stages of ripening. The free amino acid content increased throughout the cheese ripening process, with a more significant increase occurring after the first 30 days. Cheeses containing non-starter lactic acid bacteria exhibited the highest values at the end of the ripening period. Among the main amino acids, GABA was particularly abundant, especially in three of the cheese batches at the end of ripening. The autochthonous lactic acid bacteria were previously selected as non-producers of biogenic amines and this resulted in the absence of these compounds in the cheeses. Analysis of the microstructure of the cheese reflected the impact of proteolysis. Additionally, the texture profile analysis demonstrated that the cheese's hardness intensified as the ripening period progressed. The inclusion of autochthonous non-starter lactic acid bacteria in Castellano cheese production accelerated the proteolysis process, increasing significantly the free amino acids levels and improving the sensory quality of the cheeses.

Lipidomic Comparisons of Whole Cream Buttermilk Whey and Cheese Whey Cream Buttermilk of Caprine Milk.

Buttermilk is a potential material for the production of a milk fat globule membrane (MFGM) and can be mainly classified into two types: whole cream buttermilk and cheese whey cream buttermilk (WCB). Due to the high casein micelle content of whole cream buttermilk, the removal of casein micelles to improve the purity of MFGM materials is always required. This study investigated the effects of rennet and acid coagulation on the lipid profile of buttermilk rennet-coagulated whey (BRW) and buttermilk acid-coagulated whey (BAW) and compared them with WCB. BRW has significantly higher phospholipids (PLs) and ganglioside contents than BAW and WCB. The abundance of arachidonic acid (ARA)- and eicosapentaenoic acid (EPA)-structured PLs was higher in WCB, while docosahexaenoic acid (DHA)-structured PLs were higher in BRW, indicating that BRW and WCB intake might have a greater effect on improving cardiovascular conditions and neurodevelopment. WCB and BRW had a higher abundance of plasmanyl PL and plasmalogen PL, respectively. Phosphatidylcholine (PC) (28:1), LPE (20:5), and PC (26:0) are characteristic lipids among BRW, BAW, and WCB, and they can be used to distinguish MFGM-enriched whey from different sources.

Comparison of hyperspectral imaging and spectrometers for prediction of cheeses composition.

Artisanal cheeses are part of the heritage and identity of different countries or regions. In this work, we investigated the spectral variability of a wide range of traditional Brazilian cheeses and compared the performance of different spectrometers to discriminate cheese types and predict compositional parameters. Spectra in the visible (vis) and near infrared (NIR) region were collected, using imaging (vis/NIR-HSI and NIR-HSI) and conventional (NIRS) spectrometers, and it was determined the chemical composition of seven types of cheeses produced in Brazil. Principal component analysis (PCA) showed that spectral variability in the vis/NIR spectrum is related to differences in color (yellowness index) and fat content, while in NIR there is a greater influence of productive steps and fat content. Partial least squares discriminant analysis (PLSDA) models based on spectral information showed greater accuracy than the model based on chemical composition to discriminate types of traditional Brazilian cheeses. Partial least squares (PLS) regression models based on vis/NIR-HSI, NIRS, NIR-HSI data and HSI spectroscopic data fusion (vis/NIR + NIR) demonstrated excellent performance to predict moisture content (RPD > 2.5), good ability to predict fat content (2.0 < RPD < 2.5) and can be used to discriminate between high and low protein values (∼1.5 < RPD < 2.0). The results obtained for imaging and conventional equipment are comparable and sufficiently accurate, so that both can be adapted to predict the chemical composition of the Brazilian traditional cheeses used in this study according to the needs of the industry.

Isolation and identification of milk-clotting proteases from Prinsepia utilis Royle and its application in cheese processing.

The aim of this study was to isolate and identify the main milk-clotting proteases from Prinsepia utilis Royle. Protein isolates obtained using precipitation with 20 %-50 % ammonium sulfate (AS) showed higher milk-clotting activity (MCA) at 154.34 + 0.35 SU. Two milk-clotting proteases, namely P191 and P1831, with molecular weight of 49.665 kDa and 68.737 kDa, respectively, were isolated and identified using liquid chromatography-mass spectrometry (LC-MS/MS). Bioinformatic analysis showed that the two identified milk-clotting proteases were primarily involved in hydrolase activity and catabolic processes. Moreover, secondary structure analysis showed that P191 structurally consisted of 40.85 % of alpha-helices, 15.96 % of beta-strands, and 43.19 % of coiled coil motifs, whereas P1831 consisted of 70 % of alpha-helices, 7.5 % of beta-strands, and 22.5 % of coiled coil motifs. P191 and P1831 were shown to belong to the aspartic protease and metalloproteinase types, and exhibited stability within the pH range of 4-6 and good thermal stability at 30-80 °C. The addition of CaCl2 (<200 mg/L) increased the MCA of P191 and P1831, while the addition of NaCl (>3 mg/mL) inhibited their MCA. Moreover, P191 and P1831 preferably hydrolyzed kappa-casein, followed by alpha-casein, and to a lesser extent beta-casein. Additionally, cheese processed with the simultaneous use of the two proteases isolated in the present study exhibited good sensory properties, higher protein content, and denser microstructure compared with cheese processed using papaya rennet or calf rennet. These findings unveil the characteristics of two proteases isolated from P. utilis, their milk-clotting properties, and potential application in the cheese-making industry.

Unveiling ochratoxin A and ochratoxigenic fungi in Brazilian artisanal Cheeses: Insights from production to consumption.

Ochratoxin A (OTA) is a toxin produced by several Aspergillus species, mainly those belonging to section Circumdati and section Nigri. The presence of OTA in cheese has been reported recently in cave cheese in Italy. As artisanal cheese production in Brazil has increased, the aim of this study was to investigate the presence of ochratoxin A and related fungi in artisanal cheese consumed in Brazil. A total of 130 samples of artisanal cheeses with natural moldy rind at different periods of maturation were collected. Of this total, 79 samples were collected from 6 producers from Canastra region in the state of Minas Gerais, since this is the largest artisanal cheese producer region; 13 samples from one producer in the Amparo region in the state of São Paulo and 36 samples from markets located in these 2 states. Aspergillus section Circumdati occurred in samples of three producers and some samples from the markets. A. section Circumdati colony counts varied from 102 to 106 CFU/g. Molecular analysis revealed Aspergillus westerdijkiae (67 %) as the most frequent species, followed by Aspergillus ostianus (22 %), and Aspergillus steynii (11 %). All of these isolates of A. section Circumdati were able to produce OTA in Yeast Extract Sucrose Agar (YESA) at 25 °C/7 days. OTA was found in 22 % of the artisanal cheese samples, ranging from 1.0 to above 1000 µg/kg, but only five samples had OTA higher than 1000 µg/kg. These findings emphasize the significance of ongoing monitoring and quality control in the artisanal cheese production process to minimize potential health risks linked to OTA contamination.

Formation of Key Aroma Compounds During 30 Weeks of Ripening in Gouda-Type Cheese Produced from Pasteurized and Raw Milk.

Gouda-type cheeses were produced on a pilot-scale from raw milk (RM-G) and pasteurized milk (PM-G). Sixteen key aroma compounds previously characterized by the sensomics approach were quantitated in the unripened cheeses and at five different ripening stages (4, 7, 11, 19, and 30 weeks) by means of stable isotope dilution assays. Different trends were observed in the formation of the key aroma compounds. Short-chain free fatty acids and ethyl butanoate as well as ethyl hexanoate continuously increased during ripening but to a greater extent in RM-G. Branched-chain fatty acids such as 3-methylbutanoic acid were also continuously formed and reached a 60-fold concentration after 30 weeks, in particular in PM-G. 3-Methylbutanal and butane-2,3-dione reached a maximum concentration after 7 weeks and decreased with longer ripening. Lactones were high in the unripened cheeses and increased only slightly during ripening. Recent results have shown that free amino acids were released during ripening. The aroma compounds 3-methylbutanal, 3-methyl-1-butanol, and 3-methylbutanoic acid are suggested to be formed by microbial enzymes degrading the amino acid l-leucine following the Ehrlich pathway. To gain insight into the quantitative formation of each of the three aroma compounds, the conversion of the labeled precursors (13C6)-l-leucine and (2H3)-2-keto-4-methylpentanoic acid into the isotopically labeled aroma compounds was studied. By applying the CAMOLA approach (defined mixture of labeled and unlabeled precursor), l-leucine was confirmed as the only precursor of the three aroma compounds in the cheese with the preferential formation of 3-methylbutanoic acid.

Influence of Milk Pasteurization on the Key Aroma Compounds in a 30 Weeks Ripened Pilot-Scale Gouda Cheese Elucidated by the Sensomics Approach.

Gouda cheese was produced from pasteurized milk and ripened for 30 weeks (PM-G). By application of gas chromatography/olfactometry and an aroma extract dilution analysis on the volatiles isolated by extraction/SAFE distillation, 25 odor-active compounds in the flavor dilution (FD) factor range from 16 to 4096 were identified. Butanoic acid, 2- and 3-methylbutanoic acid, and acetic acid showed the highest FD factors, and 2-phenylethanol, δ-decalactone, and δ-dodecalactone were most odor-active in the neutral-basic fraction. Quantitations by stable isotope dilution assays followed by a calculation of odor activity values (OAVs) revealed acetic acid, 3-methylbutanoic acid, butanoic acid, and butane-2,3-dione with the highest OAVs. Finally, an aroma recombinate prepared based on the quantitative data well agreed with the aroma profile of the PM-G. In Gouda cheese produced from raw (nonpasteurized) milk (RM-G), qualitatively the same set of odor-active compounds was identified. However, higher OAVs of butanoic acid, hexanoic acid, and their corresponding ethyl esters were found. On the other hand, in the PM-G, higher OAVs for 3-methylbutanoic acid, 3-methylbutanol, 3-methylbutanal, and butane-2,3-dione were determined. The different rankings of these key aroma compounds clearly reflect the aroma differences of the two Gouda-type cheeses. A higher activity of lipase in the RM-G and higher amounts of free l-leucine in PM-G on the other side were responsible for the differences in the concentrations of some key aroma compounds.

Thermosonication as an effective substitution for fusion in Brazilian cheese spread (Requeijão Cremoso) manufacturing: The effect of ultrasonic power on technological properties.

In this initial study, the impact of thermosonication as an alternative to the traditional fusion in Brazilian cheese spread (Requeijão Cremoso) manufacture was investigated. The effect of ultrasound (US) power was evaluated considering various aspects such as gross composition, microstructure, texture, rheology, color, fatty acid composition, and volatile compounds. A 13 mm US probe operating at 20 kHz was used. The experiment involved different US power levels (200, 400, and 600 W) at 85 °C for 1 min, and results were compared to the conventional process in the same conditions (85 °C for 1 min, control treatment). The texture became softer as ultrasound power increased from 200 to 600 W, which was attributed to structural changes within the protein and lipid matrix. The color of the cheese spread also underwent noticeable changes for all US treatments, and treatment at 600 W resulted in increased lightness but reduced color intensity. Moreover, the fatty acid composition of the cheese spread showed variations with different US power, with samples treated at 600 W showing lower concentrations of saturated and unsaturated fatty acids, as well as lower atherogenicity and thrombogenicity indexes, indicating a potentially healthier product. Volatile compounds were also influenced by US, with less compounds being identified at higher powers, especially at 600 W. This could indicate possible degradation, which should be evaluated in further studies regarding US treatment effects on consumer perception. Hence, this initial work demonstrated that thermosonication might be interesting in the manufacture of Brazilian cheese spread, since it can be used to manipulate the texture, color and aroma of the product in order to improve its quality parameters.

Occurrence, Risk Implications, Prevention and Control of CIT in Monascus Cheese: A Review.

Monascus is a filamentous fungus that has been used in the food and pharmaceutical industries. When used as an auxiliary fermenting agent in the manufacturing of cheese, Monascus cheese is obtained. Citrinin (CIT) is a well-known hepatorenal toxin produced by Monascus that can harm the kidneys structurally and functionally and is frequently found in foods. However, CIT contamination in Monascus cheese is exacerbated by the metabolic ability of Monascus to product CIT, which is not lost during fermentation, and by the threat of contamination by Penicillium spp. that may be introduced during production and processing. Considering the safety of consumption and subsequent industrial development, the CIT contamination of Monascus cheese products needs to be addressed. This review aimed to examine its occurrence in Monascus cheese, risk implications, traditional control strategies, and new research advances in prevention and control to guide the application of biotechnology in the control of CIT contamination, providing more possibilities for the application of Monascus in the cheese industry.

Physicochemical and Sensory Characterization of Whey Protein-Enriched Semihard Cheese.

In view of potential future changes of German food legislation with regard to cheese product quality parameters, this study aimed to evaluate the quality of whey protein-enriched semihard cheese (WPEC). Model WPEC was produced in a pilot plant and on an industrial scale by adding defined amounts of high-heat (HH) milk to the cheese milk and comprehensively analyzed during cheese processing. The dry matter, total protein, pure protein, fat, and sodium chloride content of six-week ripened cheese samples were not significantly different (p < 0.05) when the technologically necessary heating of the curd was adapted to the amount of HH milk. However, the ripening, firmness, and melting behavior of WPEC was different compared to cheese without HH milk. During ripening, no formation of whey protein peptides was observed, but differences in the amount of some bitter peptides deriving from the casein fraction were found. Sensory data suggested a slightly more bitter taste perception by the panelists for the WPEC. Further technological adjustments are recommended to obtain marketable WPEC.

Comparison of the targeted metabolomics and nutritional quality indices of the probiotic cheese enriched with microalgae.

The objective of this study is to evaluate the influence of mixed L. acidophilus LA-5 and enrichment with microalgae (C. vulgaris and A. platensis) on metabolomic formation in a brined cheese matrix. Microbiological, compositional, and metabolomic characterization were investigated during the ripening. It was found that the nutritional quality indices of the samples were based on amino acid and fatty acid characterization. Fifty-six metabolomics including fatty acids, amino acids, organic acids, minerals, and vitamins were detected using the HPLC-DAD, GC-MS, and ICP-OES-based methods. The results indicated that the enrichment with probiotic strain and microalgae led to an increase in the nutritional quality indices such as EAAI, NI, BV, MUFA/SFA, h/H, and DFA. The chemometric analysis (e.g. HCA and PCA) presented the variance between the cheese samples based on their attributes. The identification of cheese metabolomics throughout the ripening could be used for a better understanding of the functional ingredients-cheese matrix relationships and as a directive approach for novel dairy products in other metabolomic-related studies.

Production of a Cheese-Like Aroma via Fermentation of Plant Proteins and Coconut Oil with the Basidiomycetes Cyclocybe aegerita and Trametes versicolor.

Cheese is one of the most common dairy products and is characterized by its complex aroma. However, in times of climate change and resource scarcity, the possibility to mimic the characteristic cheese-like aroma from plant-based sources is in demand to offer alternatives to cheese. Accordingly, the production of a natural cheese-like aroma via fermentation of four plant-based proteins and coconut oil with basidiomycetes has been addressed. Mixtures of soy and sunflower protein with coconut oil (15 g/L) have shown the formation of a cheese-like aroma after 72 and 56 h after fermentation with Cyclocybe aegerita and Trametes versicolor, respectively. Isovaleric acid, butanoic acid, ethyl butanoate, 1-octen-3-ol, and various ketones were identified as the key odorants. Similarities to typical cheeses were observed by the principal component analysis. Overall, the finding offered an approach to a sustainable production of a natural cheese-like aroma from a plant source, thus contributing to the development of cheese alternatives.

Influence of acidification and re-neutralization on mineral equilibria and physicochemical properties of model cheese feed.

Cheese feed is used as spray-dryer feed in cheese powder production, where there is growing consumer demand to eliminate calcium-chelating salts (ES). To develop ES-free feed production processes, it is essential to investigate the relationship between pH, structural changes, and mineral solubilization. This study investigated the influence of acidification and pH re-neutralization on calcium equilibria and stability of ES-free model cheese feeds. The goal was to increase protein availability by solubilizing colloidal calcium phosphate (CCP) and to assess whether CCP solubilization is reversible upon re-neutralization. The extent of acidification (to pH 4.2 or pH 4.7) significantly affected the irreversibility of calcium solubilization upon re-neutralization. Moreover, re-neutralization treatment seemed to induce changes in protein-fat interactions. Feed viscosity was mainly influenced by the final pH, rather than the re-neutralization history. These results offer new insights into the complex interplay of pH, structural modifications, mineral solubilization, and stability in cheese feed production.

Study on application of biocellulose-based material for cheese packaging.

Bacterial cellulose (BC, biocellulose) is a natural polymer of microbiological origin that meets the criteria of a biomaterial for food packaging. The aim of the research was to obtain biocellulose and test its chemical as well as physical characterization as a potential packaging for Dutch-type cheeses. Four variants of biocellulose-based material were obtained: not grinded and grinded variants obtained from YPM medium (YPM-BCNG and YPM-BCG, respectively) and not grinded and grinded variants from acid whey (AW) (AW-BCNG and AW-BCG, respectively). It was demonstrated that AW-BCNG exhibited the highest thermostability and the highest degradation temperature (348 °C). YPM-BCG and YPM-BCNG demonstrated higher sorption properties (approx. 40 %) compared to AW-BCG and AW-BCNG (approx. 15 %). Cheese packaged in biocellulose (except for YPM-BCNG) did not differ in water, fat, or protein content compared to the control cheese. All of the biocellulose packaging variants provided the cheeses with protection against unfavourable microflora. It was demonstrated that cheeses packaged in biocellulose were characterized by lower hardness, fracturability, gumminess, and chewiness than the control cheese sample. The results obtained indicate that BC may be a suitable packaging material for ripening cheeses, which shows a positive impact on selected product features.

Changes of physicochemical and functional properties of processed cheese made with natural cheddar and mozzarella cheeses during refrigerated storage.

The present study aimed to investigate changes of physicochemical and functional properties of the processed cheeses (PCs) made with Cheddar (PC1), Mozzarella (PC2) and both of them at a ratio of 1:1 (PC3) during storage at 4 °C for 4 months. The results showed that the type of natural cheese used affected the composition of PCs with lower fat content in PC2 due to the lower fat content of Mozzarella cheese used. PC2 with lower fat content showed decreased meltability and oil leakage compared with PC1 and PC3. The stretchability of all the samples significantly (P < 0.05) decreased during storage, and PC1 showed lower stretchability. This was confirmed by increased protein hydrolysis of all the samples during the storage with a higher level of proteolysis in PC1, leading to decreased stretchability of PCs. Further low-field nuclear magnetic resonance analysis indicated more entrapped water in cheese due to moisture migration into the cheese matrix that might squeeze the fat globules to aggregate, causing more fat leakage during later stages of storage. This was evidenced by microstructural analysis showing different extents of increase in fat particle sizes and decrease in free serum in all the PC samples over the storage time. Therefore, the present study provides further understanding of the mechanism of quality change of PC during refrigerated storage as affected by proteolytic properties and composition of natural cheese used.

Effectiveness of modified atmosphere and vacuum packaging in preserving the volatilome of Stelvio PDO cheese over time.

We aimed to assay the effectiveness of vacuum or modified atmosphere packaging in preserving the organoleptic characteristics of already ripened slices of Stelvio Protected Designation of Origin cheese during 3 months of storage. A multi-omics panel, including metagenomic and metabolomic analyses, was implemented together with physicochemical and sensory analyses. Among the 177 volatiles identified, 30 out of the 50 potent odorants were found to be prevalent, regardless of packaging. Isovaleric acid showed the highest relative intensity in all samples. Caproic and caprylic acids always increased during storage, while metabolites such as dodecane and 2,3-butanediol always decreased. Slow proteolysis occurred during storage, but did not differentiate cheese samples. The type of packaging differentiated the microbiota and volatile profile, with modified atmosphere packaging keeping the volatilome more stable. Out of the 50 potent odorants, 9 were relevant to sample discrimination, with 8-nonen-2-one, 2-nonanone, and caproic acid being more abundant in stored samples.

Discriminative power of DNA-based, volatilome, near infrared spectroscopy, elements and stable isotopes methods for the origin authentication of typical Italian mountain cheese using sPLS-DA modeling.

Origin authentication methods are pivotal in counteracting frauds and provide evidence for certification systems. For these reasons, geographical origin authentication methods are used to ensure product origin. This study focused on the origin authentication (i.e. at the producer level) of a typical mountain cheese origin using various approaches, including shotgun metagenomics, volatilome, near infrared spectroscopy, stable isotopes, and elemental analyses. DNA-based analysis revealed that viral communities achieved a higher classification accuracy rate (97.4 ± 2.6 %) than bacterial communities (96.1 ± 4.0 %). Non-starter lactic acid bacteria and phages specific to each origin were identified. Volatile organic compounds exhibited potential clusters according to cheese origin, with a classification accuracy rate of 90.0 ± 11.1 %. Near-infrared spectroscopy showed lower discriminative power for cheese authentication, yielding only a 76.0 ± 31.6 % classification accuracy rate. Model performances were influenced by specific regions of the infrared spectrum, possibly associated with fat content, lipid profile and protein characteristics. Furthermore, we analyzed the elemental composition of mountain Caciotta cheese and identified significant differences in elements related to dairy equipment, macronutrients, and rare earth elements among different origins. The combination of elements and isotopes showed a decrease in authentication performance (97.0 ± 3.1 %) compared to the original element models, which were found to achieve the best classification accuracy rate (99.0 ± 0.01 %). Overall, our findings emphasize the potential of multi-omics techniques in cheese origin authentication and highlight the complexity of factors influencing cheese composition and hence typicity.

Elemental Fingerprinting of Pecorino Romano and Pecorino Sardo PDO: Characterization, Authentication and Nutritional Value.

Sardinia, located in Italy, is a significant producer of Protected Designation of Origin (PDO) sheep cheeses. In response to the growing demand for high-quality, safe, and traceable food products, the elemental fingerprints of Pecorino Romano PDO and Pecorino Sardo PDO were determined on 200 samples of cheese using validated, inductively coupled plasma methods. The aim of this study was to collect data for food authentication studies, evaluate nutritional and safety aspects, and verify the influence of cheesemaking technology and seasonality on elemental fingerprints. According to European regulations, one 100 g serving of both cheeses provides over 30% of the recommended dietary allowance for calcium, sodium, zinc, selenium, and phosphorus, and over 15% of the recommended dietary intake for copper and magnesium. Toxic elements, such as Cd, As, Hg, and Pb, were frequently not quantified or measured at concentrations of toxicological interest. Linear discriminant analysis was used to discriminate between the two types of pecorino cheese with an accuracy of over 95%. The cheese-making process affects the elemental fingerprint, which can be used for authentication purposes. Seasonal variations in several elements have been observed and discussed.

Cross-sectional, commercial testing, and chromatographic study of the occurrence of antibiotic residues throughout an artisanal raw milk cheese production chain.

This study investigated antibiotic utilization in artisanal dairies and residue occurrence throughout the raw milk cheese production chain using commercial testing (Charm KIS and Eclipse Farm3G) and UHPLC-QqQ-MS/MS and LC-QqQ-MS/MS. The cross-sectional survey results revealed gaps in the producers' knowledge of antibiotic use. Commercial testing detected antibiotic levels close to the LOD in 12.5 % of the samples, mainly in raw milk and whey, with 10.0 % testing positive, specifically in fresh and ripened cheeses, indicating that antibiotics are concentrated during cheese-making. Chromatographically, several antibiotics were identified in the faeces of healthy animals, with chlortetracycline (15.7 ± 34.5 µg/kg) and sulfamethazine (7.69 ± 16.5 µg/kg) predominating. However, only tylosin was identified in raw milk (3.28 ± 7.44 µg/kg) and whey (2.91 ± 6.55 µg/kg), and none were found in fresh or ripened cheeses. The discrepancy between commercial and analytical approaches is attributed to compounds or metabolites not covered chromatographically.