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1.
Int J Mol Sci ; 22(6)2021 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-33799462

RESUMO

In silico and in vitro methods were used to analyze ACE- and DPP-IV-inhibiting potential of Gouda cheese with a modified content of ß-casein. Firstly, the BIOPEP-UWM database was used to predict the presence of ACE and DPP-IV inhibitors in casein sequences. Then, the following Gouda cheeses were produced: with decreased, increased, and normative content of ß-casein after 1 and 60 days of ripening each (six variants in total). Finally, determination of the ACE/DPP-IV-inhibitory activity and the identification of peptides in respective Gouda-derived water-soluble extracts were carried out. The identification analyses were supported with in silico calculations, i.e., heatmaps and quantitative parameters. All Gouda variants exhibited comparable ACE inhibition, whereas DPP-IV inhibition was more diversified among the samples. The samples derived from Gouda with the increased content of ß-casein (both stages of ripening) had the highest DPP-IV-inhibiting potency compared to the same samples measured for ACE inhibition. Regardless of the results concerning ACE and DPP-IV inhibition among the cheese samples, the heatmap showed that the latter bioactivity was predominant in all Gouda variants, presumably because it was based on the qualitative approach (i.e., peptide presence in the sample). Our heatmap did not include the bioactivity of a single peptide as well as its quantity in the sample. In turn, the quantitative parameters showed that the best sources of ACE/DPP-IV inhibitors were all Gouda-derived extracts obtained after 60 days of the ripening. Although our protocol was efficient in showing some regularities among Gouda cheese variants, in vivo studies are recommended for more extensive investigations of this subject.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Caseínas/química , Queijo/análise , Inibidores da Dipeptidil Peptidase IV/isolamento & purificação , Inibidores da Enzima Conversora de Angiotensina/química , Biologia Computacional , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/química , Humanos , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética
2.
J Dairy Sci ; 104(5): 6283-6294, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33888221

RESUMO

Production of artisan cheeses, including surface-ripened cheeses, has increased in the United States over the past 2 decades. Although many of these cheesemakers report unique quality and spoilage problems during production, a systematic assessment of the quality concerns facing this sector of specialty cheese production has not been conducted. Here we report the effects of microbial spoilage and quality issues on US artisan cheese production. In a survey of 61 cheesemakers, the most common issues reported were undesirable surface molds (71%) and incorrect or unexpected colors or pigments on rinds (54%). When asked, 18% of participants indicated that they were extremely concerned about quality and spoilage problems, and they indicated that their quality standards are frequently not met, either annually (39%) or monthly (33%). Although most of the respondents (62%) said that just 0 to 5% of their cheese was lost or rendered less valuable due to quality issues annually, a small number (7% combined) reported large losses of 20 to 30% or >30% of their product lost or rendered less valuable. Almost all respondents (95%) agreed that improved quality would reduce waste, increase profits, and improve production. The survey respondents indicated in open response questions that they want access to more online resources related to quality issues and digital forums to discuss issues with experts and peers when problems arise. These findings represent the first attempt to document and estimate the effect of quality and spoilage on the American artisan cheese industry. Future work should investigate what technologies, interventions, or information could reduce losses from these problems.


Assuntos
Queijo , Animais , Queijo/análise , Cor , Microbiologia de Alimentos , Fungos , Inquéritos e Questionários , Estados Unidos
3.
J Dairy Sci ; 104(5): 5133-5140, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33663866

RESUMO

This study aimed to evaluate the effect of Lacticaseibacillus casei 01 as a probiotic culture on the production of volatile organic compounds and metabolic profile of Minas Frescal cheese. Lactose (α-lactose and ß-lactose), fatty acids (unsaturated and saturated), citric acid, tryptophan, and benzoic acid were the main compounds. Compared with the control cheese, probiotic cheese was characterized by the highest concentration of tryptophan and presented a higher number of volatile acids. The control cheese was characterized by the highest concentration of benzoic acid and fatty acids, resulting in a higher number of volatile alcohols and esters. No differences were observed for α-lactose, ß-lactose, and citric acid contents. A clear separation of probiotic and control Minas Frescal cheese was obtained using 1H nuclear magnetic resonance spectra, demonstrating that the addition of probiotic culture altered the metabolic profile of Minas Frescal cheese. Overall, the findings suggested that the addition of probiotic culture promoted the proteolysis in the fresh cheeses, decreased the lipolysis, and altered the volatile compounds. Furthermore, nuclear magnetic resonance spectroscopy coupled to chemometrics tools could be used to differentiate probiotic and conventional cheeses.


Assuntos
Queijo , Probióticos , Compostos Orgânicos Voláteis , Animais , Queijo/análise , Espectroscopia de Ressonância Magnética , Metaboloma , Compostos Orgânicos Voláteis/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-33668630

RESUMO

This review article focuses on the technological aspects and microbiological critical points of pressed-cooked cheeses processed from raw ewe's milk without the inoculation of starter cultures, in particular "Pecorino" cheese typology produced in Italy. After showing the composition of the biofilms adhering to the surface of the traditional dairy equipment (mainly wooden vat used to collect milk) and the microbiological characteristics of PDO Pecorino Siciliano cheese manufactured throughout Sicily, this cheese is taken as a case study to develop a strategy to improve its hygienic and safety characteristics. Basically, the natural lactic acid bacterial populations of fresh and ripened cheeses were characterized to select an autochthonous starter and non-starter cultures to stabilize the microbial community of PDO Pecorino Siciliano cheese. These bacteria were applied at a small scale level to prove their in situ efficacy, and finally introduced within the consortium for protection and promotion of this cheese to disseminate their performances to all dairy factories. The innovation in PDO Pecorino Siciliano cheese production was proven to be respectful of the traditional protocol, the final cheeses preserved their typicality, and the general cheese safety was improved. An overview of the future research prospects is also reported.


Assuntos
Queijo , Lactobacillales , Animais , Queijo/análise , Feminino , Microbiologia de Alimentos , Higiene , Leite , Ovinos , Sicília
5.
J Dairy Sci ; 104(4): 3832-3852, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33551157

RESUMO

Skin bag Tulum cheeses traditionally produced in the Central Taurus region of Turkey were studied to identify peptide profiles by liquid chromatography-tandem mass spectrometry over 180 d of ripening. After mass spectrometry analysis, 203 peptides were identified: 59 from αS1-casein (CN), 11 from αS2-CN, 129 from ß-CN, and 4 from κ-CN. Numbers of αS1- and ß-CN-derived peptides increased with increasing number of ripening days due to the dependence of newly formed peptides on proteolysis. However, similar increases were not observed for αS2- and κ-CN-derived peptides. Most identified peptides consisted of ß-CN-derived peptides, followed by αS1-, αS2-, and κ-CN-derived peptides. Among these, bioactive peptides were found, including antihypertensive, antibacterial, antioxidant, dipeptidyl peptidase-4 inhibitory, metal chelating, skin regenerating, glucagon-like peptide-1 secretion enhancing, opioid, cathepsin B inhibitory, prolyl endopeptidase inhibitory, immunomodulatory, brain function improving, antiamnesic, antihypercholesterolemic, anti-inflammatory, and anticarcinogenic peptides.


Assuntos
Queijo , Animais , Caseínas , Queijo/análise , Cromatografia Líquida , Peptídeos , Turquia
6.
J Dairy Sci ; 104(4): 3956-3969, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33612240

RESUMO

The prediction of traditional goat milk coagulation properties (MCP) and curd firmness over time (CFt) parameters via Fourier-transform infrared (FTIR) spectroscopy can be of significant economic interest to the dairy industry and can contribute to the breeding objectives for the genetic improvement of dairy goat breeds. Therefore, the aims of this study were to (1) explore the variability of milk FTIR spectra from 4 goat breeds (Camosciata delle Alpi, Murciano-Granadina, Maltese, and Sarda), and to assess the possible discriminant power of milk FTIR spectra among breeds, (2) assess the viability to predict coagulation traits by using milk FTIR spectra, and (3) quantify the effect of the breed on the prediction accuracy of MCP and CFt parameters. In total, 611 individual goat milk samples were used. Analysis of variance of measured MCP and CFt parameters was carried out using a mixed model including the farm and pendulum as random factors, and breed, parity, and days in milk as fixed factors. Milk spectra for each goat were collected over the spectral range from wavenumber 5,011 to 925 × cm-1. Discriminant analysis of principal components was used to assess the ability of FTIR spectra to identify breed of origin. A Bayesian model was used to calibrate equations for each coagulation trait. The accuracy of the model and the prediction equation was assessed by cross-validation (CRV; 80% training and 20% testing set) and stratified CRV (SCV; 3 breeds in the training set, one breed in the testing set) procedures. Prediction accuracy was assessed by using coefficient of determination of validation (R2VAL), the root mean square error of validation (RMSEVAL), and the ratio performance deviation. Moreover, measured and FTIR predicted traits were compared in the SCV procedure by assessing their least squares means for the breed effect, Pearson correlations, and variance heteroscedasticity. Results showed the feasibility of using FTIR spectra and multivariate analyses to correctly assign milk samples to their breeds of origin. The R2VAL values obtained with the CRV procedure were moderate to high for the majority of coagulation traits, with RMSEVAL and ratio performance deviation values increasing as the coagulation process progresses from rennet addition. Prediction accuracy obtained with the SCV were strongly influenced by the breed, presenting general low values restricting a practical application. In addition, the low Pearson correlation coefficients of Sarda breed for all the traits analyzed, and the heteroscedastic variances of Camosciata delle Alpi, Murciano-Granadina, and Maltese breeds, further indicated that it is fundamental to consider the differences existing among breeds for the prediction of milk coagulation traits.


Assuntos
Queijo , Leite , Animais , Teorema de Bayes , Queijo/análise , Indústria de Laticínios , Feminino , Cabras , Gravidez , Espectroscopia de Infravermelho com Transformada de Fourier/veterinária
7.
J Dairy Sci ; 104(3): 2539-2552, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455752

RESUMO

The aim of this research was to study changes in the microbial populations, free AA profile, biogenic amine content, and sensory characteristics of ripened cheeses (100 and 180 d) produced in different seasons (summer, autumn, winter, and spring) from pasteurized sheep milk from 8 commercial flocks fed hay or silage diets. Twenty-one individual AA and 6 biogenic amines were determined by ultra-high performance liquid chromatography. Type of conserved forage for sheep feeding did not affect the variables studied, which is of great interest because hay and silage are low-cost ingredients for sheep feeding. Proteolysis led total free AA concentrations ranging between 35,179.26 and 138,063.71 mg/kg of cheese at 180 d of ripening. γ-Aminobutyric acid, which has been associated with beneficial effects on human health, was the second most abundant AA in all cheese samples, accounting for 15% of total free AA. Spring cheeses showed 2-fold higher concentrations of γ-aminobutyric acid than summer and autumn cheeses at the end of ripening. Overall, spring, winter, and autumn cheeses had lower average concentration of biogenic amines (431.99 mg/kg of cheese) than summer cheeses (825.70 mg/kg of cheese) as well as better sensory characteristics. Therefore, this study could provide the dairy industry with useful information for producing cheeses with valuable nutritional and sensory quality for consumers.


Assuntos
Queijo , Animais , Aminas Biogênicas/análise , Queijo/análise , Manipulação de Alimentos , Leite/química , Estações do Ano , Ovinos , Silagem
8.
J Dairy Sci ; 104(3): 2719-2734, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455758

RESUMO

This study aimed to investigate the survival of the foodborne pathogen Escherichia coli O157:H7 in white-brined cheeses as influenced by the presence of Lactobacillus reuteri. The white cheeses were made from pasteurized bovine milk inoculated with E. coli O157:H7 (cocktail of 3 strains) to achieve ∼5 log10 cfu/g with absence or presence of Lb. reuteri (∼6 log10 cfu/g). Cheese samples were brined in 10% or 15% NaCl solution and stored at 10°C and 25°C for 28 d. The white-brined cheeses were assessed for salt content, pH, water activity (Aw), and numbers of E. coli O157:H7, Lb. reuteri, nonstarter lactic acid bacteria (NSLAB), yeasts, and molds. Results showed that E. coli O157:H7 survived in cheese stored in both brine solutions at 10°C and 25°C regardless of the presence of Lb. reuteri. A substantial reduction was observed in cheese stored in 10% NaCl brine at 25°C, followed by cheese stored in 15% NaCl brine at 10°C by 2.64 and 2.16 log10 cfu/g, respectively, in the presence of Lb. reuteri and by 1.02 and 1.87 log10 cfu/g, respectively, in the absence of Lb. reuteri under the same conditions. The pathogen in brine solutions survived but at a lower rate. Furthermore, the growth of Lb. reuteri and NSLAB were enhanced or slightly decreased in cheese and brine by 28 d, respectively. The salt concentrations of cheese ranged from 4 to 6% and 5 to 7% (wt/wt), during 28-d ripening in 10 and 15% brine, respectively. Values of pH and Aw slightly increased at d 1 after exposure to brine and reached 4.69 to 6.08 and 0.91 to 0.95, respectively, in all treatments. Therefore, the addition of Lb. reuteri can be used as a biopreservation method to inhibit the survival of E. coli O157:H7 in white-brined cheese when combined with the appropriate temperature, NaCl level, and storage time.


Assuntos
Queijo , Escherichia coli O157 , Lactobacillus reuteri , Animais , Bovinos , Queijo/análise , Contagem de Colônia Microbiana/veterinária , Manipulação de Alimentos , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Sais , Temperatura
9.
J Agric Food Chem ; 69(2): 717-729, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33406836

RESUMO

This work aimed to determine the formation over time of 3-methylbutanal and 3-methylbutan-1-ol recognized as malty during the manufacture of Raclette-type cheese and the fermention of reconstituted skim milk, and filter-sterilized MRS broth. Using dynamic headspace-vacuum transfer in trap extraction followed by gas chromatography coupled with mass spectrometry-olfactometry (DHS-VTT-GC-MS-O) as a screening method for the malty compounds, five compounds (2-methylpropanal, 2- and 3-methylbutanal, and 2- and 3-methylbutan-1-ol) were identified as potential compounds causing the malty aroma in starter culture development and Raclette-type cheeses. Focus on compounds having a predominant sensorial effect (3-methylbutanal and 3-methylbutan-1-ol), spikings of leucine, 13C-labeled leucine, α-ketoisocaproic acid, and α-ketoglutaric acid provided a better understanding of their formation pathway. This study highlighted the discrepancies in the formation of 3-methylbutanal and 3-methylbutan-1-ol between the growth media; namely, despite the presence of free leucine available in MRS and the addition of an excess, no increase of the target compounds was observed. The concentration of these compounds in MRS increased only when α-ketoglutaric acid or α-ketoisocaproic acid was added, and a preference for the pathway to α-hydroxyisocaproic acid instead of 3-methylbutanal was shown. In addition, a formation of 3-methylbutanal when the bacteria were not yet active was observed when spiking α-ketoisocaproic acid, which potentially indicates that this part of the metabolism could take place extracellularly. These results could potentially unveil other, not-yet-identified reactants, directly influencing the production of compounds responsible for the malty aroma in Raclette cheese.


Assuntos
Aldeídos/metabolismo , Queijo/análise , Leite/química , Odorantes/análise , Animais , Bovinos , Queijo/microbiologia , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Lactobacillales/metabolismo , Leite/microbiologia , Olfatometria , Suíça
10.
Food Chem ; 346: 128911, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33450647

RESUMO

Tyramine (TYR) is a vasoactive biogenic amine found in food products due to improper storage and poor hygiene. High TYR intake results in a wide range of life-threatening physiological reactions. The work optimizes a solid-state potentiometric sensor in the absence of a reported potentiometric method for rapid and direct TYR assay. The optimization study included thirteen membrane cocktails of different compositions. The optimized sensor proved a near-Nernstian slope of 57.30 mV/decade, a quantification limit of 10.6 ppm, and a detection limit of 7.9 ppm. Validation results confirmed the sensor ability for the direct assay of TYR in blue cheese, aged cheese, Egyptian pickled cottage cheese, and pickled herring. A comparison with the reported chromatographic method expresses the merits and potentials of the developed sensor for the rapid testing of food edibility, quality, and safety based on its TYR content. Chemical compounds studied in this article: Tyramine (PubChem CID: 5610); Tyramine hydrochloride (PubChem CID: 66449); Poly(vinyl chloride) (PubChem SID: 24864273); Tricresyl phosphate (PubChem CID: 6529); sodium phosphotungstate tribasic hydrate (PubChem SID: 329753864).


Assuntos
Biomarcadores/análise , Queijo/análise , Potenciometria/métodos , Tiramina/análise , Egito , Conservação de Alimentos , Limite de Detecção , Reprodutibilidade dos Testes
11.
Food Chem ; 347: 128955, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486360

RESUMO

Understanding which volatile compounds discriminate between products can be useful for quality, innovation or product authenticity purposes. As dataset size and dimensionality increase, linear chemometric techniques like partial least squares discriminant analysis and variable identification (PLS-DA-VID) may not identify the most discriminant compounds. This research compared the performance of self-organizing maps and entropy-based feature selection (SOM-EFS) and PLS-DA-VID to identify discriminant compounds in 17 blue cheese varieties. A total of 172 volatiles were detected using headspace solid phase microextraction, gas chromatography and mass spectrometry, including 1-nonene and 2,6-dimethylpyridine, which were newly identified in blue cheese. Despite SOM-EFS selecting only 14 volatiles compared to 78 for PLS-DA-VID, SOM-EFS proved more effectively discriminant and improved the median five-fold cross-validated prediction accuracy of the model to 0.94 compared to 0.82 for PLS-DA-VID. These findings introduce SOM-EFS as a powerful non-linear exploratory data analysis approach in the field of volatile analytical chemistry.


Assuntos
Queijo/análise , Entropia , Análise de Alimentos/métodos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Análise Discriminante , Cromatografia Gasosa-Espectrometria de Massas , Análise dos Mínimos Quadrados , Microextração em Fase Sólida
12.
J Dairy Sci ; 104(2): 1445-1453, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309367

RESUMO

The study aimed to evaluate the effects of linseed and oregano supplementation to the diet of goats on fatty acid profile and sensory properties of Padraccio, a typical cheese produced during spring through summer in the Basilicata region (southern Italy). Extruded linseed and dried oregano inflorescences were integrated in the pelleted concentrate supplementation (500 g/head per day) in 21 grazing goats that were randomly assigned, 7 per group, to the following experimental treatments: concentrate, concentrate with addition of linseed, and concentrate with addition of linseed and oregano. Pooled milk from each group was used in cheesemaking. From a nutritional perspective, integration of extruded linseed in the goat diet improved the fatty acid profile of Padraccio cheese. Moreover, the cheese from this group evidenced the highest scoring on color, flavor, texture, and overall liking.


Assuntos
Queijo/análise , Ácidos Graxos/análise , Linho , Cabras , Leite/química , Origanum , Animais , Dieta/veterinária , Suplementos Nutricionais , Feminino , Itália , Lactação
13.
J Sci Food Agric ; 101(1): 327-333, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32629541

RESUMO

BACKGROUND: Yak milk formed stronger rennet-induced gels if the milk contained smalled casein micelles and a higher concentration of calcium. Also casein gels could formed after a shorter incubation time if the milk contained smalled casein micelles. The objective of this study was to estimate the importance of yak casein micelle size on rennet-induced coagulation properties. RESULTS: Three fractions of different-sized, undamaged casein micelles (Ф112.17 ± 0.83 nm, Ф207.13 ± 0.59 nm and Ф269.37 ± 2.89 nm) were obtained by ultracentrifugation. The smallest casein micelles had the highest concentrations of calcium (803.21 ± 8.49 mM), phosphate (445.52 ± 10.66 mM), and κ-casein/total casein (19.45%). Rheological analyses determined the optimal gelation times of small, medium, and large casein micelles to be 9.5 ± 0.5, 10.8 ± 0.5, and 13.3 ± 0.2 min, respectively. Higher κ-casein concentration in the small casein micelles appeared to facilitate their shorter incubation time. Both the faster caseinomacropeptide (CMP) release rate and rennet-induced aggregation rate of small casein micelles contributed to a faster change in turbidity. Furthermore, small casein micelles had the highest elastic modulus (G', 73.21 ± 4.5 Pa) 60 min after the addition of rennet. This was consistent with micro-photographs, which showed that small casein micelles could form a more homogeneous gel, which had smaller pore sizes. Trial cheese manufacture verified that yak cheese containing small casein micelles, formed curd faster and the cheese had higher texture profile analysis (TPA) values for hardness, cohesiveness, and springiness. CONCLUSION: This is important information for the optimization of yak cheese industrial production. © 2020 Society of Chemical Industry.


Assuntos
Caseínas/química , Quimosina/química , Animais , Bovinos , Queijo/análise , Micelas , Leite/química , Agregados Proteicos , Reologia
14.
J Dairy Sci ; 104(3): 2581-2593, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33358802

RESUMO

Milk fan is a cheese-like fermented milk product produced in Yunnan Province, China. In this study, we characterized the microbial communities of milk fan from 6 distinct geographical origins and investigated their generation of volatile organic compounds (VOC). The microbial communities found in all milk fan samples were dominated by Lactococcus, Lactobacillus, and Raoultella bacteria and Rhodotorula, Torulaspora, and Candida fungi. Samples from the Kunming and Weishan regions had greater bacterial richness, and samples from Xizhou had greater fungal community richness. Sixty prominent VOC (i.e., those having odor activity values ≥1), including esters, acids, alcohols, aldehydes, ketones, and aromatic compounds, were identified by gas chromatography-mass spectrometry analysis of milk fan samples. Pearson correlation analysis revealed that Lactobacillus, Rhodotorula, Lodderomyces, and Debaryomyces had significant correlations with various VOC, revealing a total of 13 compounds that are characteristic of the odor of milk fan. These bacteria and fungi are therefore identified as functional microorganisms that collectively create the complex VOC profile of milk fan. This study provides a comprehensive overview of the microbial community of milk fan and demonstrates its contribution to the unique aroma profile of this fermented milk product.


Assuntos
Queijo , Microbiota , Compostos Orgânicos Voláteis , Animais , Queijo/análise , China , Leite/química , Compostos Orgânicos Voláteis/análise
15.
J Dairy Sci ; 104(2): 1560-1575, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309346

RESUMO

Consumer perception of smoked cheese was evaluated through focus groups, surveys, and central location testing. Three focus groups (n = 29) were conducted with consumers of smoked cheese. Subsequently, 2 online surveys were conducted. The purpose of the first survey (n = 1,195) was to understand types of smoked cheeses consumed and if consumers associated specific wood smokes with smoked cheese. Next, an adaptive choice-based conjoint (n = 367) was designed to evaluate consumer perception of different attributes of smoked cheese. Maximum difference scaling and familiarity questions were also included in the adaptive choice-based conjoint survey. Following the surveys, a central location test (n = 135) was conducted with cheeses smoked with 3 different woods at a low and high intensity (6 cheeses total). Hierarchical Bayesian estimation, 1-way ANOVA, agglomerative hierarchical clustering, and 2-way ANOVA (smoke type × intensity level) were used to interpret the collected data. Results from the focus groups indicated that smoked cheese was perceived as an artisan, high-end product and that appearance and price were strong purchase factors. In general, consumers were not aware of how smoked flavor was imparted to cheese, but when informed of the processes, they preferred cold-smoked cheese to the addition of liquid smoke flavor. Results from both surveys confirmed focus group observations. Consumers perceived flavor differences among different wood smokes and smoked products. Method of smoking, smoke intensity, type of wood, and type of cheese were the most important attributes for purchase of smoked cheese. When tasting, consumers differentiated smoke aroma and flavor among cheeses and preferred cherry wood smoked cheeses over apple wood or hickory smoked cheeses. Understanding consumer perceptions of smoked cheese will give insight into the desired experience that consumers expect when purchasing smoked cheese.


Assuntos
Queijo/análise , Comportamento do Consumidor , Preferências Alimentares/psicologia , Adolescente , Adulto , Animais , Teorema de Bayes , Queijo/normas , Análise por Conglomerados , Feminino , Aromatizantes/química , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Fumaça , Inquéritos e Questionários , Paladar , Percepção Gustatória , Adulto Jovem
16.
J Dairy Sci ; 104(2): 1576-1590, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33358170

RESUMO

To determine the odor-active compounds in Cheddar cheeses with different ripening times (6, 10, and 14 mo), 39 potent odorants of Cheddar cheeses were identified with a flavor dilution factor range between 1 and 512 by aroma extract dilution analysis. To further determine their contribution to the overall aroma profile of Cheddar cheeses, odor activity values of 38 odorants with flavor dilution factors ≥1 were calculated. A Cheddar cheese matrix was developed to determine the concentrations and the odor thresholds of these key aroma compounds. The result of the aroma recombinant experiment prepared by mixing the key aroma compounds in the concentrations in which they occurred in Cheddar cheeses showed that the overall aroma profile of the recombinant sample was very similar to that of Cheddar cheese. The main different compounds in Cheddar cheese with different ripening time were acetic acid, butanoic acid, dimethyl trisulfide, methional, hexanal, (E)-2-nonenal, acetoin, 1-octen-3-one, δ-dodecalactone, furaneol, hexanoic acid, heptanal, and ethyl caproate. This study could provide important information for researching and developing Cheddar cheese-related products.


Assuntos
Queijo/análise , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Adulto , Animais , Cromatografia Gasosa , Feminino , Humanos , Masculino , Espectrometria de Massas , Percepção , Microextração em Fase Sólida , Fatores de Tempo
17.
J Sci Food Agric ; 101(2): 555-563, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32672836

RESUMO

BACKGROUND: In Southern European countries, whey cheeses are normally produced with ovine or caprine whey. Cow's cheese whey can also be used, although the whey cheese yield is low (2-3%, w/v) which discourages its use. In the present study, bovine cheese whey was concentrated by ultrafiltration for the production of four types of whey cheeses (Requeijão): conventional, without any addition (WC); with 10% (w/w) addition of cream (WCC); with cream fermented with Kefir culture (WCCK); and with cream fermented with Bifidobacterium sp. culture (WCCBB12). RESULTS: Whey cheeses with cream presented lower protein content (330-360 g kg-1 , dry basis) and higher levels of total solids (220-250 g kg-1 ) and fat (300-330 g kg-1 , dry basis) than WC. C16:0 and C18:1 were the most abundant fatty acids present, with 31% and 38%, respectively. The small differences found concerning instrumental determination of colour and texture were not perceived by panelists. However, the presence of Kefir and probiotics decreased the elastic modulus (G') of the samples, as well as their viscosity. Fermentation with Kefir presented the highest counts of lactic acid bacteria (7 logUFC g-1 ). However, after 14 days of refrigerated storage, the counts of yeasts and moulds reached 6 logUFC g-1 in all products, indicating the need for appropriate packaging solutions. CONCLUSION: Ultrafiltration of bovine whey allows for the efficient production of bovine whey cheeses. The addition of cream fermented with Kefir or BB12 appears to be an efficient methodology to incorporate Kefir or probiotic bacteria in Requeijão, improving its nutritional and sensory characteristics, alongside the potential for the extension of its shelf-life. © 2020 Society of Chemical Industry.


Assuntos
Bifidobacterium/metabolismo , Queijo/microbiologia , Microbiologia de Alimentos/métodos , Kefir/microbiologia , Probióticos/metabolismo , Ultrafiltração/métodos , Soro do Leite/microbiologia , Animais , Bovinos , Queijo/análise , Módulo de Elasticidade , Fermentação , Kefir/análise , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/metabolismo , Leite/química , Leite/microbiologia , Probióticos/análise , Ovinos , Soro do Leite/química
18.
Food Chem ; 336: 127699, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768905

RESUMO

Cheese is one of the most widely consumed food products in the world. However, the increasing demand for nutritionally enhanced or functional products by the cheese industry has created new approaches that partially or fully replace milk fat. With this, new methods of adulteration have also been noted, potentially leading to these fully/partially-replaced products being offered as cheese. In this study, Raman spectroscopy was used to determine origins of fats in margarine, corn, and palm oils present in white and ultra-filtered cheese samples. Raman spectra were evaluated with partial least square-discriminant (PLS-DA) and PLS to identify fat/oil origins and adulteration ratios. The coefficients of determination and limits of detection for margarine, and corn and palm oil adulteration were found to be 0.990, 0.993, 0.991 and 3.38%, 3.36% and 3.59%, respectively.


Assuntos
Queijo/análise , Análise de Dados , Gorduras/análise , Análise de Alimentos/métodos , Leite/química , Análise Espectral Raman , Ultrafiltração , Animais , Contaminação de Alimentos/análise , Análise dos Mínimos Quadrados , Análise Multivariada
19.
Food Chem ; 336: 127625, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771897

RESUMO

The solubility of carbon dioxide (CO2) in the moisture and protein components of cheese matrices and the influence of changing pH, salt and temperature levels remains unclear. In this study, model casein matrices were prepared, by renneting of micellar casein concentrate (MCC), with modulation of salt and pH levels by adding salt and glucono delta-lactone, respectively, to the MCC solutions prior to renneting. Different moisture-to-protein levels were achieved by freeze-drying, incubation of samples at different relative humidities, or by applying varying pressures during gel manufacture. The CO2 solubility of samples decreased linearly with both increasing temperature and salt-in-moisture content, whereas solubility of CO2 increased with increasing pH. A non-linear relationship was observed between CO2 solubility and the moisture-to-protein ratio of experimental samples. Overall, such knowledge may be applied to improve the quality and consistency of eye-type cheese, and in particular to avoid development of undesirable slits and cracks.


Assuntos
Dióxido de Carbono/química , Caseínas/química , Cloreto de Sódio/química , Água/química , Queijo/análise , Concentração de Íons de Hidrogênio , Pressão Parcial , Solubilidade , Temperatura
20.
Food Chem ; 338: 128013, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091995

RESUMO

Chitosan-procyanidin composite films (CS-PC films) with different mass ratios were prepared by solution casting method. Their structural, thermal, physical, and antioxidant properties, antibacterial activity and pH responsivity were determined. Compared with CS-control film, CS-PC films exhibited lower solubility and higher tensile strength. The antimicrobial properties against Escherichia coli and Aspergillus niger were improved by 20.0% and 30.4%, respectively. CS-PC films indicated good antioxidant activity through their DPPH and ABTS+ scavenging rates, which were 2.45 times higher than CS-control film. pH responsivity was represented by the outstanding changes in color, which were visible to the naked eye. Food packaging film with high antioxidant activity, bacteriostatic properties and pH responsivity was prepared by CS and PC. Compared with the initial properties of cheese, the characteristics of cheese packaged with CS-PC films were obviously better than those of the control groups.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Biflavonoides/química , Catequina/química , Queijo/análise , Quitosana/química , Embalagem de Alimentos/métodos , Proantocianidinas/química , Anti-Infecciosos/farmacologia , Aspergillus niger/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio
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