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1.
Hig. Aliment. (Online) ; 38(298): e1144, jan.-jun. 2024.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1531444

RESUMO

As falhas na higienização em um estabelecimento de alimentos podem refletir em problemas causando a contaminação ou deterioração do produto produzido. Esta pesquisa foi motivada por reclamações de consumidores informando que os queijos apresentaram fungos, mesmo estando dentro do prazo de validade e por solicitação do Serviço de Inspeção Municipal. O objetivo desta pesquisa foi avaliar a contaminação ambiental em uma agroindústria da agricultura familiar produtora de queijo colonial no Sudoeste Paranaense. Foram realizadas a contagem para aeróbios mesófilos em equipamentos e superfícies que entram em contato com o alimento e análise microbiológica ambiental de bolores e leveduras na sala de secagem dos queijos. A coleta foi realizada com método de esfregaço de suabe estéril para aeróbios mesófilos e semeadas em placas de Petri com Ágar Padrão de Contagem. Para a coleta ambiental foram expostas placas de Petri com ágar Saboraund durante 15 minutos. Os resultados demonstraram ausência de contaminação nas superfícies, mas foram encontrados bolores e leveduras de forma acentuada na sala de secagem dos queijos, o que pode contribuir para a deterioração do produto, diminuindo sua validade. Para minimizar as perdas por contaminação é necessário que o processo de higienização dos ambientes seja realizado de forma eficiente.


Failures in hygiene in a food establishment can result in problems causing contamination or deterioration of the product produced. This research was motivated by complaints from consumers reporting that the cheeses had mold, even though they were within their expiration date and at the request of the Municipal Inspection Service. This research was to evaluate environmental contamination in an agroindustry in the family farm producing colonial cheese in Southwest Paraná. For the microbiological assessment of environmental contamination, counting for mesophilic aerobes was carried out on equipment and surfaces that come into contact with food and, environmental microbiological analysis of molds and yeast in the cheese drying room. The collection was carried out using the sterile swab smear for mesophilic aerobes and seeded in Petri dishes with Counting Standard Agar. For environmental collection, sheets of Petri with Saboraund agar for 15 minutes. The results demonstrated absence of contamination on surfaces. But the presence of molds and yeasts in the drying room cheeses, which can contribute to the deterioration of the product and thus reduce the validity. To minimize losses due to contamination, it is It is necessary that the process of cleaning and disinfecting environments is carried out efficiently.


Assuntos
Higiene dos Alimentos , Queijo/microbiologia , Brasil , Boas Práticas de Fabricação , Doenças Transmitidas por Alimentos/prevenção & controle
2.
Molecules ; 29(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731432

RESUMO

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.


Assuntos
Queijo , Conservação de Alimentos , Derivados da Hipromelose , Própole , Queijo/microbiologia , Queijo/análise , Própole/química , Derivados da Hipromelose/química , Conservação de Alimentos/métodos , Fenóis/química , Fenóis/análise , Microbiologia de Alimentos , Escherichia coli/efeitos dos fármacos
3.
J Agric Food Chem ; 72(19): 11268-11277, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695399

RESUMO

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.


Assuntos
Leitelho , Queijo , Cabras , Lipidômica , Soro do Leite , Animais , Leitelho/análise , Queijo/análise , Soro do Leite/química , Fosfolipídeos/análise , Fosfolipídeos/química , Glicolipídeos/química , Leite/química , Gotículas Lipídicas/química , Glicoproteínas/química , Glicoproteínas/análise , Lipídeos/química , Lipídeos/análise
4.
Food Res Int ; 186: 114306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729707

RESUMO

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.


Assuntos
Aminoácidos , Aminas Biogênicas , Queijo , Proteólise , Queijo/microbiologia , Queijo/análise , Aminoácidos/análise , Aminoácidos/metabolismo , Aminas Biogênicas/análise , Microbiologia de Alimentos , Manipulação de Alimentos/métodos , Leuconostoc/metabolismo , Leuconostoc/crescimento & desenvolvimento , Lactobacillus/metabolismo , Lactobacillus/crescimento & desenvolvimento , Nitrogênio/análise , Qualidade dos Alimentos , Fermentação
5.
J Agric Food Chem ; 72(19): 11072-11079, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38699886

RESUMO

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.


Assuntos
Queijo , Leite , Odorantes , Pasteurização , Compostos Orgânicos Voláteis , Queijo/análise , Animais , Leite/química , Leite/metabolismo , Odorantes/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Bovinos
6.
J Agric Food Chem ; 72(19): 11062-11071, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38700435

RESUMO

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.


Assuntos
Queijo , Leite , Odorantes , Olfatometria , Pasteurização , Compostos Orgânicos Voláteis , Queijo/análise , Leite/química , Odorantes/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Animais , Aromatizantes/química , Bovinos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Paladar
7.
BMC Infect Dis ; 24(1): 493, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745170

RESUMO

BACKGROUND: Diet plays an important role in Helicobacter pylori (HP) infection, and our objective was to investigate potential connections between dietary patterns, specific food groups, and HP infection status in U.S. adults. METHODS: The data for this study was obtained from the NHANES (National Health and Nutrition Survey) database for the year 1999-2000. This cross-sectional study involved the selection of adults aged 20 years and older who had undergone dietary surveys and HP testing. Factor analysis was employed to identify dietary patterns, and logistic regression models were utilized to assess the association between these dietary patterns and specific food groups with HP infection status. RESULT: Based on the inclusion and exclusion criteria, our final analysis included 2,952 individuals. The median age of participants was 51.0 years, and 48.7% were male. In the study population, the overall prevalence of HP infection was 44.9%. Factor analysis revealed three distinct dietary patterns: High-fat and high-sugar pattern (including solid fats, refined grains, cheese, and added sugars); Vegetarian pattern (comprising fruits, juices, and whole grains); Healthy pattern (encompassing vegetables, nuts and seeds, and oils). Adjusted results showed that the high-fat and high-sugar pattern (OR = 0.689, 95% CI: 0.688-0.690), vegetarian pattern (OR = 0.802, 95% CI: 0.801-0.803), and healthy pattern (OR = 0.717, 95% CI: 0.716-0.718) were all linked to a lower likelihood of HP infection. Further analysis of the high-fat and high-sugar pattern revealed that solid fats (OR = 0.717, 95% CI: 0.716-0.718) and cheese (OR = 0.863, 95% CI: 0.862-0.864) were protective factors against HP infection, while refined grains (OR = 1.045, 95% CI: 1.044-1.046) and added sugars (OR = 1.014, 95% CI: 1.013-1.015) were identified as risk factors for HP infection. CONCLUSION: Both the Vegetarian pattern and the Healthy pattern are associated with a reduced risk of HP infection. Interestingly, the High-fat and High-sugar pattern, which is initially considered a risk factor for HP infection when the score is low, becomes a protective factor as the intake increases. Within this pattern, animal foods like solid fats and cheese play a protective role, while the consumption of refined grains and added sugars increases the likelihood of HP infection.


Assuntos
Queijo , Infecções por Helicobacter , Helicobacter pylori , Inquéritos Nutricionais , Humanos , Masculino , Estudos Transversais , Infecções por Helicobacter/epidemiologia , Pessoa de Meia-Idade , Feminino , Queijo/microbiologia , Adulto , Dieta , Gorduras na Dieta , Idoso , Adulto Jovem , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia , Comportamento Alimentar
8.
Water Environ Res ; 96(5): e11036, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38740567

RESUMO

The cheese making and vegetable processing industries generate immense volumes of high-nitrogen wastewater that is often treated at rural facilities using land applications. Laboratory incubation results showed denitrification decreased with temperature in industry facility soils but remained high in soils from agricultural sites (75% at 2.1°C). 16S rRNA, phospholipid fatty acid (PLFA), and soil respiration analyses were conducted to investigate potential soil microbiome impacts. Biotic and abiotic system factor correlations showed no clear patterns explaining the divergent denitrification rates. In all three soil types at the phylum level, Actinobacteria, Proteobacteria, and Acidobacteria dominated, whereas at the class level, Nitrososphaeria and Alphaproteobacteria dominated, similar to denitrifying systems such as wetlands, wastewater resource recovery facilities, and wastewater-irrigated agricultural systems. Results show that potential denitrification drivers vary but lay the foundation to develop a better understanding of the key factors regulating denitrification in land application systems and protect local groundwater supplies. PRACTITIONER POINTS: Incubation study denitrification rates decreased as temperatures decreased, potentially leading to groundwater contamination issues during colder months. The three most dominant phyla for all systems are Actinobacteria, Proteobacteria, and Acidobacteria. The dominant class for all systems is Nitrosphaeria (phyla Crenarchaeota). No correlation patterns between denitrification rates and system biotic and abiotic factors were observed that explained system efficiency differences.


Assuntos
Queijo , Desnitrificação , Microbiologia do Solo , Verduras , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Solo/química
9.
Food Res Int ; 183: 114242, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760121

RESUMO

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.


Assuntos
Queijo , Imageamento Hiperespectral , Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho , Queijo/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Imageamento Hiperespectral/métodos , Brasil , Análise Discriminante , Análise dos Mínimos Quadrados , Cor
10.
Food Res Int ; 183: 114225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760144

RESUMO

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.


Assuntos
Queijo , Manipulação de Alimentos , Peptídeo Hidrolases , Queijo/análise , Manipulação de Alimentos/métodos , Animais , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Espectrometria de Massas em Tandem , Concentração de Íons de Hidrogênio , Leite/química , Peso Molecular , Estabilidade Enzimática , Cromatografia Líquida
11.
Food Res Int ; 183: 114214, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760141

RESUMO

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.


Assuntos
Aspergillus , Queijo , Contaminação de Alimentos , Microbiologia de Alimentos , Ocratoxinas , Ocratoxinas/biossíntese , Ocratoxinas/análise , Queijo/microbiologia , Queijo/análise , Brasil , Aspergillus/metabolismo , Contaminação de Alimentos/análise , Contagem de Colônia Microbiana
12.
Food Res Int ; 187: 114308, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763625

RESUMO

Antimicrobial resistance (AMR) is a significant public health threat, with the food production chain, and, specifically, fermented products, as a potential vehicle for dissemination. However, information about dairy products, especially raw ewe milk cheeses, is limited. The present study analysed, for the first time, the occurrence of AMRs related to lactic acid bacteria (LAB) along a raw ewe milk cheese production chain for the most common antimicrobial agents used on farms (dihydrostreptomycin, benzylpenicillin, amoxicillin and polymyxin B). More than 200 LAB isolates were obtained and identified by Sanger sequencing (V1-V3 16S rRNA regions); these isolates included 8 LAB genera and 21 species. Significant differences in LAB composition were observed throughout the production chain (P ≤ 0.001), with Enterococcus (e.g., E. hirae and E. faecalis) and Bacillus (e.g., B. thuringiensis and B. cereus) predominating in ovine faeces and raw ewe milk, respectively, along with Lactococcus (L. lactis) in whey and fresh cheeses, while Lactobacillus and Lacticaseibacillus species (e.g., Lactobacillus sp. and L. paracasei) prevailed in ripened cheeses. Phenotypically, by broth microdilution, Lactococcus, Enterococcus and Bacillus species presented the greatest resistance rates (on average, 78.2 %, 56.8 % and 53.4 %, respectively), specifically against polymyxin B, and were more susceptible to dihydrostreptomycin. Conversely, Lacticaseibacillus and Lactobacillus were more susceptible to all antimicrobials tested (31.4 % and 39.1 %, respectively). Thus, resistance patterns and multidrug resistance were reduced along the production chain (P ≤ 0.05). Genotypically, through HT-qPCR, 31 antimicrobial resistance genes (ARGs) and 6 mobile genetic elements (MGEs) were detected, predominating Str, StrB and aadA-01, related to aminoglycoside resistance, and the transposons tnpA-02 and tnpA-01. In general, a significant reduction in ARGs and MGEs abundances was also observed throughout the production chain (P ≤ 0.001). The current findings indicate that LAB dynamics throughout the raw ewe milk cheese production chain facilitated a reduction in AMRs, which has not been reported to date.


Assuntos
Antibacterianos , Queijo , Farmacorresistência Bacteriana , Lactobacillales , Leite , Animais , Queijo/microbiologia , Leite/microbiologia , Ovinos , Lactobacillales/genética , Lactobacillales/efeitos dos fármacos , Lactobacillales/isolamento & purificação , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Fenótipo , Microbiologia de Alimentos , Genótipo , RNA Ribossômico 16S/genética , Testes de Sensibilidade Microbiana , Fezes/microbiologia , Feminino
13.
Microbiome ; 12(1): 78, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678226

RESUMO

BACKGROUND: Artisanal cheeses usually contain a highly diverse microbial community which can significantly impact their quality and safety. Here, we describe a detailed longitudinal study assessing the impact of ripening in three natural caves on the microbiome and resistome succession across three different producers of Cabrales blue-veined cheese. RESULTS: Both the producer and cave in which cheeses were ripened significantly influenced the cheese microbiome. Lactococcus and the former Lactobacillus genus, among other taxa, showed high abundance in cheeses at initial stages of ripening, either coming from the raw material, starter culture used, and/or the environment of processing plants. Along cheese ripening in caves, these taxa were displaced by other bacteria, such as Tetragenococcus, Corynebacterium, Brevibacterium, Yaniella, and Staphylococcus, predominantly originating from cave environments (mainly food contact surfaces), as demonstrated by source-tracking analysis, strain analysis at read level, and the characterization of 613 metagenome-assembled genomes. The high abundance of Tetragenococcus koreensis and Tetragenococcus halophilus detected in cheese has not been found previously in cheese metagenomes. Furthermore, Tetragenococcus showed a high level of horizontal gene transfer with other members of the cheese microbiome, mainly with Lactococcus and Staphylococcus, involving genes related to carbohydrate metabolism functions. The resistome analysis revealed that raw milk and the associated processing environments are a rich reservoir of antimicrobial resistance determinants, mainly associated with resistance to aminoglycosides, tetracyclines, and ß-lactam antibiotics and harbored by aerobic gram-negative bacteria of high relevance from a safety point of view, such as Escherichia coli, Salmonella enterica, Acinetobacter, and Klebsiella pneumoniae, and that the displacement of most raw milk-associated taxa by cave-associated taxa during ripening gave rise to a significant decrease in the load of ARGs and, therefore, to a safer end product. CONCLUSION: Overall, the cave environments represented an important source of non-starter microorganisms which may play a relevant role in the quality and safety of the end products. Among them, we have identified novel taxa and taxa not previously regarded as being dominant components of the cheese microbiome (Tetragenococcus spp.), providing very valuable information for the authentication of this protected designation of origin artisanal cheese. Video Abstract.


Assuntos
Queijo , Microbiologia de Alimentos , Microbiota , Queijo/microbiologia , Queijo/normas , Microbiota/fisiologia , Transferência Genética Horizontal/genética , Metagenoma/genética , Resistência Microbiana a Medicamentos/genética
14.
Int J Biol Macromol ; 266(Pt 2): 131249, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569998

RESUMO

This study investigated the development of biodegradable films made from a combination of polyethylene glycol (PEG), carboxymethyl cellulose (CMC) and mixtures from natamycin and ferulic acid. The films were characterized for their surface microstructure, antioxidant activity, thermal stability, mechanical properties, permeability and antifungal/bacterial activity. The addition of natamycin and ferulic acid to the film matrix enhanced antioxidant activity, thermal stability, antimicrobial activity, reduced the water vapor permeability (WVP) to 1.083 × 10-10 g × m-1s-1Pa-1, imparted opaque color and increased opacity up to 3.131 A mm-1. The attendance of natamycin and ferulic acid inside films created a clear roughness shape with agglomerates on the surface of films and caused a clear inhibition zone for Aspergillus niger, E. coli and C. botulinum. The utilization of PG/CMC/N-F packaging material on Ras cheese had a noticeable effect, resulting in a slight decrease in moisture content from 34.23 to 29.17 %. Additionally, it helped maintain the titrable acidity within the range of 0.99 % to 1.11 % and the force required for puncture from 0.035 to 0.052 N with non-significant differences. Importantly, these changes did not significantly affect the sensory qualities of Ras cheese during the storage period.


Assuntos
Antioxidantes , Carboximetilcelulose Sódica , Ácidos Cumáricos , Embalagem de Alimentos , Natamicina , Polietilenoglicóis , Antioxidantes/farmacologia , Antioxidantes/química , Polietilenoglicóis/química , Embalagem de Alimentos/métodos , Carboximetilcelulose Sódica/química , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Natamicina/farmacologia , Natamicina/química , Permeabilidade , Disponibilidade Biológica , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Queijo , Vapor
15.
J Agric Food Chem ; 72(17): 9567-9580, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38627202

RESUMO

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.


Assuntos
Queijo , Citrinina , Contaminação de Alimentos , Monascus , Monascus/metabolismo , Monascus/química , Queijo/microbiologia , Queijo/análise , Citrinina/análise , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Humanos , Fermentação
16.
Food Res Int ; 184: 114210, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609211

RESUMO

When casein is replaced with starch in imitation cheese, the functionality changes. Three different microscopy methods were applied to understand the microstructural differences in the product depending on which component dominates the microstructure. Confocal Laser Scanning Microscopy (CLSM) for component identification. Scanning Electron Microscopy (SEM) and Cryogenic Scanning Electron Microscopy (Cryo-SEM) for studying surface structures. Differences in the surface structures were detected between SEM and Cryo-SEM. In SEM, starch appeared rough and protein smooth, while in Cryo-SEM no starch roughness of the surface was found. A change in starch modification and effects of protein prehydration was also analysed. Adding octenyl succinic anhydride (OSA) modified starch for emulsifying properties resulted in a microstructure with fragmented protein at a protein level of 7 %, but not at 9 or 12 %. Protein prehydration had limited effect on microstructure. On a macrostructural level, the change to an emulsifying starch increased hardness in imitation cheese with 7 and 9 % protein. Protein prehydration slightly decreased the hardness, but the difference was not significant at all concentrations. This research provides valuable information about the microstructure of imitation cheese at a 50/50 composition, how the microstructure changes with an emulsifying starch and what occurs after a protein prehydration was included in the production.


Assuntos
Queijo , Comportamento Imitativo , Microscopia Eletrônica de Varredura , Caseínas , Amido
17.
Open Vet J ; 14(1): 594-603, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38633143

RESUMO

Background: The utilization of chemical preservatives holds the promise of effectively controlling microbial growth in soft cheese. Aim: The first trial aimed to compare the effectiveness of lactobionic acid (LBA) and K-Sorbate in controlling the proliferation of Staphylococcus aureus, Escherichia coli, and mold in white soft cheese. The subsequent part of the study explored the inhibitory effects of K-Sorbate, nisin, and LBA on mold populations in cheese whey. Methods: Two sets of soft cheese were produced. One set was contaminated with S. aureus, while the other was with E. coli, each at concentrations of 1 log CFU/ml and 1 log CFU/100 ml. Different concentrations of LBA were incorporated into these sets of cheese. Similar cheese samples were treated with K-Sorbate. For the subsequent part of the study, it was manufactured and divided into groups that inoculated with LBA with different concentrations, K-Sorbate, and nisin. Results: With higher S. aureus inoculation, by day 18, the positive control exhibited growth exceeding 5 log CFU/g. In contrast, the LBA treatment dropped below limit of detection (LOD) and K-Sorbate yielded 4.8 log CFU/g. While with lower S. aureus inoculation, the positive control reached log CFU/g, while LBA treatment fell below LOD by day 14, and K-Sorbate reached 2.9 log CFU/g. For E. coli inoculation, with higher concentrations, by day 18, the positive control exceeded 5 log CFU/g. Conversely, LBA treatment greatly decreased and K-Sorbate treatment measured 5.1 log CFU/g. With lower E. coli concentrations, the positive control surpassed 3 log CFU/g, yet LBA treatment dropped below LOD by day 3. Mold counts indicated some inhibition with the K-Sorbate treatment, while control groups showed growth. LBA treatments exhibit noticeable growth inhibition. About the other part of the study, the outcomes demonstrated that while growth of mold occurred in the control group, inhibitory effects were apparent in the treatment groups, and significant distinctions existed between K-Sorbate, nisin, LBA treatments, and the control group. Conclusion: Our findings suggest that LBA has the potential to effectively control the growth of E. coli, S. aureus, and mold in soft cheese. Moreover, LBA displays greater preservative efficacy compared to K-Sorbate and nisin.


Assuntos
Queijo , Dissacarídeos , Nisina , Animais , Nisina/farmacologia , Escherichia coli , Staphylococcus aureus , Contagem de Colônia Microbiana/veterinária
18.
Nutr Diabetes ; 14(1): 15, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594262

RESUMO

BACKGROUND: We assessed the possible effect of usual dairy consumption on pre-diabetes (Pre-DM) remission or progression to type 2 diabetes (T2D). METHODS: Pre-DM adults (n = 334, mean age of 49.4 years, and 51.5% men) were assessed for dairy intakes (2006-2008) and followed up to 9 years for incidence of T2D or normal glycemia (NG). All biochemical measurements were done at baseline and all subsequent examinations with 3-y follow-up intervals. Multinomial regression models with adjustment of confounding variables were used to estimate odds ratios (OR) and 95% confidence intervals (CIs) of incident T2D and NG for each serving/d dairy consumption. RESULTS: The odds of NG was significantly elevated by 69% (OR = 1.69, 95% CI = 1.00-2.86, P = 0.05) per 200 g/d increased high-fat dairy intake, while the amount of total dairy or low-fat dairy was not related to the outcomes. Higher intakes of yogurt were more likely to be associated with an increased odds of NG (OR = 1.82, 95% CI = 1.20-2.74, P = 0.01). Usual intakes of milk, cheese, or cream-butter were not associated to Pre-DM remission or progression to T2D. CONCLUSION: Regular dairy consumption may increase the chance of Pre-DM regression to NG.


Assuntos
Queijo , Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Feminino , Animais , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Estado Pré-Diabético/epidemiologia , Seguimentos , Leite , Dieta , Fatores de Risco
19.
Food Microbiol ; 121: 104514, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637076

RESUMO

The enzymatic repertoire of starter cultures belonging to the Lactococcus genus determines various important characteristics of fermented dairy products but might change in response to the substantial environmental changes in the manufacturing process. Assessing bacterial proteome adaptation in dairy and other food environments is challenging due to the high matrix-protein concentration and is even further complicated in particularly cheese by the high fat concentrations, the semi-solid state of that matrix, and the non-growing state of the bacteria. Here, we present bacterial harvesting and processing procedures that enable reproducible, high-resolution proteome determination in lactococcal cultures harvested from laboratory media, milk, and miniature Gouda cheese. Comparative proteome analysis of Lactococcus cremoris NCDO712 grown in laboratory medium and milk revealed proteome adaptations that predominantly reflect the differential (micro-)nutrient availability in these two environments. Additionally, the drastic environmental changes during cheese manufacturing only elicited subtle changes in the L. cremoris NCDO712 proteome, including modified expression levels of enzymes involved in flavour formation. The technical advances we describe offer novel opportunities to evaluate bacterial proteomes in relation to their performance in complex, protein- and/or fat-rich food matrices and highlight the potential of steering starter culture performance by preculture condition adjustments.


Assuntos
Queijo , Produtos Fermentados do Leite , Lactococcus lactis , Animais , Proteoma/metabolismo , Fermentação , Queijo/microbiologia , Leite/microbiologia , Lactococcus lactis/genética , Lactococcus lactis/metabolismo
20.
Food Microbiol ; 121: 104521, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637083

RESUMO

Natural whey starters (NWS) are cultures with undefined multiple-strains species commonly used to speed up the fermentation process of cheeses. The aim of this study was to explore the diversity and the viability of Comté cheese NWS microbiota. Culture-dependent methods, i.e. plate counting and genotypic characterization, and culture-independent methods, i.e. qPCR, viability-qPCR, fluorescence microscopy and DNA metabarcoding, were combined to analyze thirty-six NWS collected in six Comté cheese factories at two seasons. Our results highlighted that NWS were dominated by Streptococcus thermophilus (ST) and thermophilic lactobacilli. These species showed a diversity of strains based on Rep-PCR. The dominance of Lactobacillus helveticus (LH) over Lactobacillus delbrueckii (LD) varied depending on the factory and the season. This highlighted two types of NWS: the type-ST/LD (LD > LH) and the type-ST/LH (LD < LH). The microbial composition varied depending on cheese factory. One factory was distinguished by its level of culturable microbial groups (ST, enterococci and yeast) and its fungi diversity. The approaches used to estimate the viability showed that most NWS cells were viable. Further investigations are needed to understand the microbial diversity of these NWS.


Assuntos
Queijo , Lactobacillus delbrueckii , Lactobacillus helveticus , Soro do Leite , Queijo/microbiologia , Microbiologia de Alimentos , Proteínas do Soro do Leite/análise , Streptococcus thermophilus/genética
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