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1.
Braz. J. Pharm. Sci. (Online) ; 58: e20324, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420453

RESUMO

Abstract This study investigated the synergy testing of penicillin, cephalosporin, amphenicols, and aminoglycoside in the camel milk (n=768 samples), subsequently used for isolation of MDR S. aureus targeting mecA gene. Antibiotic susceptibility of S. aureus showed >90% isolates were sensitive to ciprofloxacin and trimethoprim and resistant against oxacillin, ampicillin, and cefoxitin. Further, 50-85% of the S. aureus were sensitive to gentamicin, oxytetracycline, and chloramphenicol and resistant against cefotaxime, vancomycin, and cefixime. Minimum inhibitory concentration (MIC) of cefotaxime, (C) and ampicillin (A) in combination with gentamicin (G) was reduced by 99.34% and 70.46%, respectively, while with chloramphenicol (Ch), reduction was 57.49% and 60%, respectively. In addition, the Fractional Inhibitory Concentration Index (FICI) of G+A, Ch+C and Ch+G combinations showed synergy against 80%, 60%, and 30% of MDR S. aureus, respectively. Similarly, C+A and Ch+G displayed indifferent interaction against 70 % and 30% of isolates, respectively, while the later showed additive interaction against 10% of MDR S. aureus. Altogether, our results described effective combination of gentamicin and chloramphenicol with ampicillin and cefotaxime to combat MDR S. aureus


Assuntos
Penicilinas/agonistas , Staphylococcus aureus/patogenicidade , Cloranfenicol/agonistas , Sinergismo Farmacológico , Aminoglicosídeos/agonistas , Camelus/classificação , Testes de Sensibilidade Microbiana/instrumentação , Genes MDR , Leite/classificação
2.
São Paulo; s.n; s.n; 2022. 129 p. tab, graf.
Tese em Português | LILACS | ID: biblio-1415356

RESUMO

O objetivo deste estudo foi desenvolver uma formulação de bebida láctea bubalina probiótica adicionada de polpa de morango, comparando os efeitos do uso do leite de búfala e de vaca na elaboração dos produtos e verificando a possibilidade de suplementação com triptofano nos produtos lácteos probióticos. Como primeira etapa do trabalho, bebidas lácteas probióticas foram elaboradas a partir de leite bubalino e bovino, fermentadas com Streptococcus thermophilus TA040, Lactobacillus bulgaricus LB340 e Lactobacillus acidophilus La5, e formuladas com 0, 25 e 50% de soro em sua formulação. As bebidas foram avaliadas quanto à cinética de fermentação das culturas láticas utilizadas, ao teor de proteína, gordura e sólidos totais não gordurosos, pós-acidificação, viabilidade das culturas fermentadoras e sua capacidade de sobrevivência ao estresse gastrointestinal in vitro. As bebidas lácteas bubalinas apresentaram resultados superiores as bebidas bovinas. O uso do leite de búfala na elaboração das bebidas lácteas promoveu benefícios quanto as culturas láticas presentes nos produtos, exercendo efeito protetivo e influindo na preservação da viabilidade das bactérias ao longo do armazenamento refrigerado e durante a simulação do estresse gastrointestinal in vitro. As bebidas lácteas elaboradas com 25% apresentaram os resultados mais próximos aos obtidos pelos produtos controle, sem adição de soro, sendo selecionadas para a segunda parte do estudo. Nesta etapa, as formulações de bebida láctea com 25% de soro, foram acrescidas de um preparado com polpa de morango e bebidas sem adição da fruta, utilizadas como controle. As bebidas lácteas bubalinas frutadas, apresentaram menor teor de gordura e melhores características reológicas, com maior viscosidade e consistência do que os produtos controle, sem afetar a pós-acidificação, o perfil de ácido graxo, assim como, a viabilidade e a resistência às condições de estresse gastrointestinal in vitro das culturas fermentadoras. A avaliação da possibilidade de suplementar lácteos probióticos com triptofano foi realizada em conjunto com a Universidade de Milão. Para isso, iogurtes probióticos receberam adição de triptofano antes ou após a fermentação, sendo avaliados com relação ao perfil de pós-acidificação, quantidade de triptofano nos produtos, número de células viáveis por plaqueamento e citometria de fluxo ao longo do armazenamento a 25° e 4°C. Complementarmente, a influência da presença do triptofano no crescimento e produção de compostos antimicrobianos pelas culturas láticas, também foi avaliada. A adição de triptofano após a fermentação dos iogurtes, que foram armazenados sob refrigeração (4°C), além de não afetar a pós-acidificação dos produtos, apresentou benefícios quanto a viabilidade L. acidophilus, redução do dano e aumento do número de células vivas, promovendo teor maior do aminoácido nos iogurtes. A presença do triptofano nos meios de cultivo, também influenciou de forma positiva o crescimento de S. thermophilus e L. acidophilus, melhorando o desenvolvimento das bactérias durante a fermentação e influindo em uma maior atividade antilistérica por parte do S. thermophilus. Diante da influência positiva da aplicação do leite de búfala na elaboração das bebidas lácteas, assim como, a adição do triptofano em iogurtes probióticos, a suplementação do aminoácido em bebidas lácteas bubalinas frutadas permitiria a obtenção de um produto funcional, onde seus benefícios estariam relacionados tanto ao consumo do probiótico presente no produto quanto a complementação de triptofano na dieta do consumidor


The aim of this study was to develop a formulation of probiotic buffalo dairy beverage added with strawberry pulp, comparing the effects of using buffalo and cow's milk in the preparation of products and verifying the possibility of tryptophan supplementation in probiotic dairy products. As a first stage of the work, probiotic dairy beverages were made from buffalo and bovine milk, fermented with Streptococcus thermophiles TA040, Lactobacillus bulgaricus LB340 and Lactobacillus acidophilus La5, and formulated with 0, 25 and 50% whey in their formulation. The beverages were evaluated for the fermentation kinetics of the used lactic cultures, the levels of protein, fat and total no fat solids, post-acidification, fermenting cultures viability and their ability to survive gastrointestinal stress in vitro. Buffalo milk use in dairy beverages production promoted benefits regarding the lactic cultures present in the products, exerting a protective effect and influencing the viability preservation of bacteria during the cold storage and simulation of gastrointestinal stress in vitro. Dairy beverages made with 25% whey addition showed results similar to those obtained by the control products, without whey addition, being selected for the second part of the study. In this part, the dairy beverages formulations with 25% whey, were added with a preparation were added with a strawberry pulp preparation and dairy beverages without added fruit, used as a control. Fruity bubaline dairy beverages had lower fat content and better rheological characteristics, with higher viscosity and consistency than control products, without affecting post-acidification, fatty acid profile, as well as viability and resistance to in vitro gastrointestinal condition of fermented cultures. The possibility of supplementing probiotic dairy products with tryptophan was evaluated in partnership with the University of Milan. For this, probiotic yogurts received the addition of tryptophan before or after fermentation, being evaluated in relation to the post-acidification profile, tryptophan amount in the products, viable cell number per plating and flow cytometry during storage at 25°C and 4°C. In addition, the influence of the tryptophan presence on the growth and production of antimicrobial compounds by lactic cultures was also evaluated. The addition of tryptophan after the yogurt fermentation, which were stored under refrigeration (4°C), in addition to not affecting the post-acidification of the products, showed benefits to the viability of L. acidophilus, reduced the damage and increased the number of cells promoting higher amino acid content in yogurts. Tryptophan presence in the culture media also positively influenced the growth of S. thermophiles and L. acidophilus, improving the development of bacteria during fermentation and influencing better antilisteric activity in the part of S. thermophiles. In view of the buffalo milk positive influence observed after the application in dairy beverage preparation, as well as the addition of tryptophan in probiotic yoghurts, amino acid supplementation in fruity buffalo dairy beverages would allow to obtain a functional product, where its benefits would be related both to the consumption of the probiotic present in the product as to the supplementation of tryptophan in the consumer's diet


Assuntos
Triptofano/análogos & derivados , Iogurte/análise , Bebidas/análise , Química Farmacêutica/instrumentação , Leite/classificação , Frutas/classificação , Búfalos/classificação , Citometria de Fluxo/métodos
3.
J Nutr Sci ; 10: e78, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616549

RESUMO

Undernutrition is a major global health problem. Various types of animal milk are used for feeding children at early ages; however, associations of camel milk (CaM) and bovine milk (BM) with the nutritional status of children have not been explored. A comparative community-based cross-sectional study was conducted among pre-schoolers in rural pastoral districts of Somali, Ethiopia. Children were selected from households with lactating camels or cows. Anthropometric measurements followed standard procedures for height-for-age, weight-for-age and weight-for-height scores. Independent sample t-tests identified significant differences in anthropometric indices based on the type of milk consumed. Multivariable logistic regression was used to examine associations between milk consumption and other predictors of growth failures. The prevalence of stunting was 24⋅1 % [95 % confidence interval (CI) 20⋅5, 28⋅3] of pre-schoolers, 34⋅8 % (95 % CI 29⋅9, 39⋅6) were wasted and 34⋅7 % (95 % CI 30⋅1, 39⋅9) were underweight. Higher proportions of BM-fed children were severely stunted, wasted and underweight compared with CaM consumers. Using logistic regression models, children who consumed BM [adjusted odds ratio (AOR): 2⋅10; 95 % CI 1⋅22, 3⋅61] and who were anaemic (AOR: 4⋅22; 95 % CI 2⋅23, 7⋅98) were more likely to be stunted than their counterparts, while girls were less likely to be stunted than boys (AOR: 0⋅57; 95 % CI 0⋅34, 0⋅94). Similarly, children who consumed BM (AOR: 1⋅97; 95 % CI 1⋅20, 3⋅24), who were anaemic (AOR: 2⋅27; 95 % CI 1⋅38, 3⋅72) and who drank unsafe water (AOR: 1⋅91; 95 % CI 1⋅19, 3⋅07) were more likely to be underweight than their counterparts. In conclusion, CaM consumption was associated with lower prevalence of stunting and underweight than BM. Promoting CaM in pastoralist areas may help to curb the high level of undernutrition.


Assuntos
Transtornos do Crescimento , Desnutrição , Leite , Anemia/epidemiologia , Animais , Camelus , Bovinos , Criança , Estudos Transversais , Etiópia/epidemiologia , Transtornos do Crescimento/epidemiologia , Humanos , Lactação , Desnutrição/epidemiologia , Leite/classificação , Somália , Magreza/epidemiologia
4.
Int J Obes (Lond) ; 45(12): 2623-2628, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34433906

RESUMO

BACKGROUND: International guidelines recommend children aged 9 months to 2 years consume whole (3.25%) fat cow's milk, and children older than age 2 years consume reduced (0.1-2%) fat cow's milk to prevent obesity. The objective of this study was to evaluate the longitudinal relationship between cow's milk fat (0.1-3.25%) intake and body mass index z-score (zBMI) in childhood. We hypothesized that higher cow's milk fat intake was associated with lower zBMI. METHODS: A prospective cohort study of children aged 9 months to 8 years was conducted through the TARGet Kids! primary care research network. The exposure was cow's milk fat consumption (skim (0.1%), 1%, 2%, whole (3.25%)), measured by parental report. The outcome was zBMI. Height and weight were measured by trained research assistants and zBMI was determined according to WHO growth standards. A linear mixed effects model and logistic generalized estimating equations were used to determine the longitudinal association between cow's milk fat intake and child zBMI. RESULTS: Among children aged 9 months to 8 years (N = 7467; 4699 of whom had repeated measures), each 1% increase in cow's milk fat consumed was associated with a 0.05 lower zBMI score (95% CI -0.07 to -0.03, p < 0.0001) after adjustment for covariates including volume of milk consumed. Compared to children who consumed reduced fat (0.1-2%) milk, there was evidence that children who consumed whole milk had 16% lower odds of overweight (OR = 0.84, 95% CI 0.77 to 0.91, p < 0.0001) and 18% lower odds of obesity (OR = 0.82, 95% CI 0.68 to 1.00, p = 0.047). CONCLUSIONS: Guidelines for reduced fat instead of whole cow's milk during childhood may not be effective in preventing overweight or obesity.


Assuntos
Leite/metabolismo , Obesidade Pediátrica/metabolismo , Animais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Leite/classificação , Obesidade Pediátrica/epidemiologia , Estudos Prospectivos
5.
Food Funct ; 12(12): 5417-5428, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33988206

RESUMO

Due to the prevalence and severity of cow milk (CM) allergy (CMA), an ideal substitute is urgently needed to develop hypoallergenic infant formula for infants who experience anaphylaxis to typical whey-based CM formula. Goat milk (GM) and horse milk (HM) are considered appropriate substitutes; however, whether GM and HM are less allergenic than CM is unclear. In the present study, the difference in allergenicity among CM, GM, and HM was investigated using the Balb/c mouse model. The number of mice with severe respiratory symptoms was significantly lower in the GM- and HM-sensitised groups than in the CM-sensitised group. Furthermore, histologic examination of intestinal and lung tissues revealed a thinner lamina propria of the small intestine and obvious inflammation and congestion in lungs in the CM-sensitised group than in the GM- and HM-sensitised groups. CM-specific immunoglobulin (Ig) E, serum IgG1, and plasma histamine levels were also higher in CM-sensitised mice than in GM- or HM-sensitised mice. In addition, higher interleukin (IL) 4 and IL-17A levels and lower interferon-γ (IFN-γ) and IL-10 levels were observed in CM-sensitised mice compared with GM- and HM-sensitised mice, according to qPCR, indicating Th1/Th2 and Treg/Th17 imbalances. The CM-sensitised group had a higher proportion of IL-4- and IL-17A-producing CD3+ T cells but a lower proportion of IFN-γ- and IL-10-producing CD3+ T cells compared with the GM- and HM-sensitised groups, confirming the Th1/Th2 and Treg/Th17 imbalances. In conclusion, GM and HM were less allergenic than CM in mice as a result of a shift in the Th1/Th2 and Treg/Th17 imbalances; however, HM was less allergenic than GM and can be used as an alternative milk to develop infant formulas for children with CMA.


Assuntos
Alérgenos , Hipersensibilidade a Leite/imunologia , Leite/imunologia , Administração Oral , Animais , Bovinos , Citocinas , Modelos Animais de Doenças , Feminino , Cabras , Histamina/sangue , Cavalos , Imunoglobulina E , Imunoglobulina G , Fórmulas Infantis , Inflamação , Interleucina-10 , Interleucina-17 , Interleucina-4 , Camundongos , Camundongos Endogâmicos BALB C , Leite/classificação , Células Th1 , Células Th17 , Células Th2 , Fatores de Transcrição , Soro do Leite , Proteínas do Soro do Leite/imunologia
6.
J Food Sci ; 86(4): 1283-1295, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33761138

RESUMO

This study aims at investigating whether the livestock, lactation stage, or geographical origin of specialty milk in China could be classified by the elemental contents. Samples of goat, buffalo, and yak milk were collected from main production provinces in China and the contents of nine elements in milk from different livestock, regions, and lactation stages were determined. Statistical analysis indicated that the contents of Mn, Cu, As, Se, Cs, and Mo in mature milk were significantly different between the three livestock (p < 0.05). The trends of Mn and Cs contents of the goat milk and buffalo milk increased first and then decreased gradually during lactation. The contents of Se, Cs, Ba, and Mo in mature milk of three livestock were significantly different between the three regions (p < 0.05). The result of linear discriminant analysis (LDA) and partial least squares discrimination analysis (PLS-DA) showed that the total correct classification rates in different livestock for mature milk reached 86.7 and 90%. For goat milk, the total correct classification rates of different lactations and regions reached 88.9 and 77.8% for LDA (100 and 87.5% for PLS-DA), and followed by yak milk of different regions which achieved 88.9% for LDA (88.9% for PLS-DA). In summary, the microelements in milk showed a significant correlation with livestock, region, and lactation of goat, buffalo, and yak milk. The elemental fingerprints combined with the LDA could be potential for classifying the livestock, lactation stage, and geographical origin of milk. PRACTICAL APPLICATION: According to study the contents of miroelements in milk from different livestock, regions, and lactation stages, provide evidence and support for classifying the livestock, lactation stage, and geographical origin of milk.


Assuntos
Búfalos , Bovinos , Cabras , Lactação , Leite/classificação , Oligoelementos/análise , Animais , China , Análise Discriminante , Feminino , Gado/classificação
7.
Artigo em Inglês | MEDLINE | ID: mdl-32971369

RESUMO

The main challenges in the purification of αS2-casein are due to the low quantity in milk and high homology with other casein subunits, i.e., αS1-casein, ß-casein, and κ-casein. To overcome these challenges, the aim of this study was to develop a two-step purification to isolate native αS2-casein in goat milk from five different breeds; British Alpine, Jamnapari, Saanen, Shami, and Toggenburg. The first step of the purification was executed by anion-exchange chromatography under optimal elution conditions followed by size exclusion chromatography. Tryptic peptides from in-gel digestion of purified αS2-casein were sequenced and analyzed by LC-ESI-MS/MS. From 1.05 g of whole casein, the highest yield of αS2-casein (6.7 mg/mL) was obtained from Jamnapari and the lowest yield (2.2 mg/mL) was from Saanen. A single band of pure αS2-casein was observed on SDS-PAGE for all breeds. The αS2-casein showed coverage percentage of amino acid sequence from 76.68 to 92.83%. The two-step purification process developed herein was successfully applied for isolating native αS2-casein from goat milk with high purity, which will allow for future in vitro studies to be conducted on this protein.


Assuntos
Caseínas , Cromatografia Líquida/métodos , Cabras/classificação , Leite/química , Animais , Caseínas/análise , Caseínas/química , Caseínas/classificação , Caseínas/isolamento & purificação , Cabras/metabolismo , Leite/classificação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
8.
Prev Vet Med ; 182: 105101, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32823253

RESUMO

Bovine mastitis is a major health problem that affects dairy cows and has a negative impact on milk production. The presence of microRNAs in biofluids, such as blood and milk, could play a pivotal role in the detection of bovine mastitis. The purpose of the current study was to determine the levels of microRNA gene expression in milk, in combination with other reported mastitis indicators, as a biomarker of bovine mastitis. Milk samples (n = 171) were obtained from 113 dairy cows with known disease status (i.e., healthy; n = 23 cows, subclinical mastitis; n = 45 cows, or clinical mastitis; n = 45 cows) and analyzed for the presence of MIR24-2, MIR29B-2, MIR146A, MIR148A, MIR155, MIR181A1, MIR184, and MIR223 expression using the real-time PCR (qPCR) method. The expression data were then utilized in the creation of receiver operator characteristic curves (ROC) and further analyzed by the machine learning (ML) methods. MIR29B-2, MIR146A, MIR148A, and MIR155 expression levels differed significantly among the three groups. These potential microRNA biomarkers of mastitis exhibited high sensitivity and specificity. Next, we applied ML algorithm, specifically, a decision tree (DT) model to predict the status of milk based on MIR29B-2 and MIR146A expression levels. The results suggested that MIR29B-2, when used in combination with the California mastitis test (CMT) and days in milk (DIM) data, was applicable for screening and classification of milk samples from cows as healthy, subclinical mastitis, or mastitis. MIR29B-2 appears to have sufficient discriminatory power to enable it to be utilized as a biomarker in cases where the status of a milk sample cannot be determined based on CMT results.


Assuntos
Mastite Bovina/diagnóstico , Leite/classificação , RNA Mensageiro/análise , Animais , Biomarcadores/metabolismo , Bovinos , Feminino , Mastite Bovina/microbiologia , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real/veterinária
9.
J Dairy Res ; 87(2): 239-242, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32295663

RESUMO

In this research communication we describe an innovative protocol that combines three pairs of primers, two from the literature and one designed in our laboratory, for application in triplex-PCR on somatic cell DNA to enable identification of the species origin (cow, sheep, goat) of cheeses and yogurts with a detection limit of 0.1%. Mislabeling was detected in 15 out of 40 cheeses and in 18 out of 40 yogurts tested. The suggested procedure is a quick and reliable tool for identifying the animal origin of cheeses and yogurts and it can be used to certify product reliability on the domestic and international market. Additionally, in combination with a serological test it can offer a reliable tool for detecting the presence of cow's whey.


Assuntos
Queijo/classificação , Contaminação de Alimentos/análise , Rotulagem de Alimentos/legislação & jurisprudência , Leite/classificação , Reação em Cadeia da Polimerase Multiplex/veterinária , Iogurte/classificação , Animais , Bovinos , DNA/análise , Feminino , Qualidade dos Alimentos , Cabras , Grécia , Reação em Cadeia da Polimerase Multiplex/métodos , Ovinos , Especificidade da Espécie
10.
Rev. bras. ciênc. vet ; 26(4): 152-157, out./dez. 2019. ilus, map, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1491656

RESUMO

The seasons influence the production of buffalos’ milk. Because of this, the producers may produce a mixture of buffalo and bovine milk during cheese production in periods of low production. Therefore, the present work aimed to investigate fraud in buffalo cheese and the relationship between seasonality and different physicochemical properties of buffalo cheeses produced and marketed in eastern Amazonia. We obtained commercial samples of buffalo cheese during two Amazonian climatic periods from commercial points of Marajó-Pará, Brazil. After collection, there were lipid, protein, ash, and humidity analyses. Determination of carbohydrates and energy values was also performed for the nutritional characterization of samples, as well as for mPCR analysis to detect buffalo and/or bovine DNA. DNA extraction protocol of the samples was standardized and two pairs were used for the mPCR reaction, amplifying fragments of approximately 220 bp for Bubalus bubalis DNA and 346 bp fragments for Bos taurus DNA. Among the samples acquired in the rainy season, we observed that 33% were inadequately labeled, indicating fraud from cow’s milk incorporation and fraud from substitution of raw material. From the nine samples obtained in the dry season, all the samples showed cow’s milk incorporation fraud. The highest fraud rate coincided with the period of low milk production from buffalo and there was a difference in composition between fraudulent and non-fraudulent cheeses. Therefore, seasonality influences increase in cattle milk for the production of buffalo cheese, and this adulteration may decrease the nutritional content of the product.


As estações climáticas influenciam a produção de leite de búfala. Isso pode levar os produtores a misturarem os leites de búfala e bovino durante a produção de queijo em períodos de baixa produção. Portanto, o presente trabalho teve como objetivo verificar fraudes em queijo de búfala, a relação com a sazonalidade e as diferenças físico-químicas de queijos de origem bubalina, produzidos e comercializados no leste da Amazônia. Foram coletadas amostras comerciais de queijo de búfala em dois períodos climáticos da Amazônia em pontos comerciais do Marajó-Pará, Brasil. Após a coleta foram realizadas análises de lipídios, proteínas, cinzas e umidade. A determinação dos carboidratos e do valor energético também foi feita para a caracterização nutricional das amostras, bem como a análise de mPCR para a detecção de DNA de búfalo e/ou bovino. Para isso, padronizou-se um protocolo de extração de DNA das amostras e utilizou-se dois pares na reação mPCR, amplificar fragmentos de aproximadamente 220 pb para o DNA de Bubalus bubalis e fragmentos de 346 pb para o Bos taurus. Entre as amostras adquiridas na estação chuvosa, observou-se que 33% foram rotuladas inadequadamente, caracterizando fraude por incorporação de leite de vaca e fraude por substituição de matéria-prima. Das 9 amostras coletadas no período seco, todas as amostras apresentaram fraude na incorporação do leite de vaca. Este estudo revelou que a maior taxa de fraude coincide com o período de baixa produção de leite e que há uma diferença na composição entre queijos fraudulentos e não fraudulentos. Portanto, a sazonalidade influencia no acréscimo de leite de bovinos na produção de queijo de búfala e que esta adulteração pode diminuir o conteúdo nutricional do produto.


Assuntos
Fraude , Leite/classificação , Leite/química , Produção de Alimentos , Bovinos , Estações do Ano , Reação em Cadeia da Polimerase Multiplex/veterinária
11.
Food Chem ; 294: 309-315, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126468

RESUMO

Spectra data from two instruments (UV-Vis/NIR and FT-NIR) consisting of three and one detectors, respectively, were employed in order to discriminate the geographical origin of milk as a way to detect adulteration. Initially, principal component analysis (PCA) was used to see if clusters of milk from different origins are formed. Separation between samples of different origins were not observed with PCA, hence, feed-forward multi-layer perceptron artificial neural network (MLP-ANN) models were designed. ANN models were developed by changing the number of input variables and the best models were chosen based on high values of generalized R-square and entropy R-square, as well as small values of root mean square error (RMSE), mean absolute deviation (Mean Abs. Dev), and -loglikelihood while considering 100% classification rate. Based on the results, whether the spectra data was collected from a single or three detector instrument the same clustering was observed based on geographical origin.


Assuntos
Leite/classificação , Redes Neurais de Computação , Espectrofotometria/métodos , Animais , Bovinos , Análise por Conglomerados , Entropia , Feminino , Leite/química , Análise de Componente Principal
12.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 22(4): 115-118, out-dez. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1052860

RESUMO

This study aims to evaluate a simpler methodology for determination of dry matter in three types of milk. The treatments consisted of three methodologies: AOAC (Association of Official Agricultural Chemists), characterized by the drying in porcelain capsules and pre-heating; use of analytical sand in the process of drying, as well as a simplified methodology characterized by drying in Petri dishes without analytical sand and pre-heating proceeding. The statistical analysis was performed with F test (5% significance level), Pearson's correlation and Lin's concordance correlation coefficient. All methodologies showed precision and accuracy in the measurement of the dry matter in milk, however, the simplified methodology was superior in material savings and shorter time consumption for the analysis.(AU)


Este estudo teve como objetivo avaliar metodologia simplificada de determinação de matéria seca em três tipos de leite. Os tratamentos consistiram de três metodologias: AOAC (Association of Official Agricultural Chemists), caracterizada pela secagem em cápsulas de porcelana e pré-secagem; uso de areia analítica no processo de secagem e utilização de metodologia simplificada baseada no uso de placas de Petri com secagem direta em estufa, sem o uso de areia analítica e procedimento de pré-secagem. A análise estatística envolveu o teste F ao nível de significância de 5%, correlação de Pearson e coeficiente de concordância de Lin. Todas as metodologias mostraram acurácia na determinação da matéria seca para todos os tipos de leite, mas a metodologia simplificada foi superior em economia e menor tempo de análise.(AU)


Este estudio tuvo como objetivo evaluar la metodología simplificada de determinación de materia seca en tres tipos de leche. Los tratamientos consistieron en tres metodologías: AOAC (Association of Official Agricultural Chemists), caracterizada por pre-secado y secado en cápsulas de porcelana; uso de arena analítica en el proceso de secado y utilización de metodología simplificada basada en el uso de placas de Petri con secado directo en invernadero, sin el uso de arena analítica y procedimiento de pre secado. El análisis estadístico involucró la prueba F al nivel de significancia del 5%, correlación de Pearson y coeficiente de concordancia de Lin. Todas las metodologías mostraron precisión en la determinación de la materia seca para todos los tipos de leche, pero la metodología simplificada fue superior en economía y menor tiempo de análisis.(AU)


Assuntos
Leite/classificação , Leite/química , Confiabilidade dos Dados
13.
J Dairy Res ; 86(1): 25-33, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30757981

RESUMO

This study aimed to calculate economic values (EVs) and economic selection indices for milk production systems in small rural properties. The traits 305-d milk yield in kg (MY), fat (FP) and protein (PP) percentage, daily fat (FY) and protein (PY) yield, cow live weight in kg (LW), calving interval (CI), and logarithm of daily somatic cell count (SCC) in milk were considered the goals and selection criteria. The production systems were identified from 29 commercial properties based on the inventory of revenues and costs and of zootechnical field data. Later, bioeconomic models were developed to calculate the productive performance, revenues, and costs concerning milk production to estimate EVs, which were calculated as the difference in annual profit with dairy production resulting from a change in one unit of the trait while keeping the others constant and dividing the value by the number of cows. After the EVs were known, ten economic selection indices were estimated for each system so they could be compared by modifying the selection criteria and calculating the relative importance of each selection criteria, the accuracy of the economic selection index, and response expected to the selection in USD, among other parameters. One of the systems detected was called less intensive (LS) and was characterized by having ten cows in lactation that produced 13·5 l/d and consumed 1·8 kg of concentrate/d. The second system detected was called more intensive (IS) and had 22 cows in lactation that produced 17·5 l/d and consumed 3·4 kg of concentrate/d. Monthly profits per cows in lactation of USD 2·60 and USD 68·77 were recorded for LS and IS, respectively. The EVs of the traits MY, FP, and PP were all positive, while for the other traits they were all negative in all situations. The best economic selection indices were those featuring selection criteria MY, LW, and CI, while the trait LW had the greatest importance in both systems. These results indicate that animal frame must be controlled in order to maximize the system's profit.


Assuntos
Cruzamento/economia , Cruzamento/métodos , Bovinos/genética , Indústria de Laticínios/economia , Lactação/genética , Seleção Genética , Animais , Brasil , Bovinos/fisiologia , Contagem de Células , Custos e Análise de Custo , Fazendas , Feminino , Renda , Masculino , Leite/classificação , Leite/citologia , População Rural , Clima Tropical
14.
Food Chem ; 284: 60-66, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744868

RESUMO

In the dairy industry, substitution of high priced milk species with low priced ones is a common practice, and determination of milk species is critical. In this study, synchronous fluorescence spectroscopy (SFS) method was developed for identification of milk species in fermented dairy products (yoghurt and cheese). Three partial least square-discriminant analysis models were developed in order to identify pure-mixed samples, milk species and binary mixture type, and partial least square (PLS) model was utilized to quantify the mixing ratio in binary mixtures. PLS models used for yoghurt and cheese samples showed that detection limits of adulteration were below 3.3%. Apart from the buffalo-cow yoghurt and goat-cow cheese, precision of the measurements was found to be below 6.2. It can be said that SFS technique is applicable on yoghurt and cheese samples as it's a less destructive and a less costly method compared to DNA and protein based conventional methods.


Assuntos
Produtos Fermentados do Leite/análise , Contaminação de Alimentos/análise , Leite/química , Leite/classificação , Espectrometria de Fluorescência/métodos , Animais , Búfalos , Bovinos , Queijo/análise , DNA/análise , Indústria de Laticínios , Feminino , Cabras , Análise dos Mínimos Quadrados , Limite de Detecção , Proteínas do Leite/análise , Ovinos , Especificidade da Espécie , Iogurte/análise
15.
Appl Biochem Biotechnol ; 188(2): 410-423, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30484137

RESUMO

In this study, a fungal and two yeast ß-galactosidases were immobilized using alginate and chitosan. The biochemical parameters and lactose hydrolysis abilities of immobilized enzymes were analyzed. The pH optima of immobilized fungal ß-galactosidases shifted to more acidic pH compared to free enzyme. Remarkably, the optimal temperature of chitosan-entrapped yeast enzyme, Maxilact, increased to 60 °C, which is significantly higher than that of the free Maxilact (40 °C) and other immobilized forms. Chitosan-immobilized A. oryzae ß-galactosidase showed improved lactose hydrolysis (95.7%) from milk, compared to the free enzyme (82.7%) in 12 h. Chitosan-immobilized Maxilact was the most efficient in lactose removal from milk (100% lactose hydrolysis in 2 h). The immobilized lactases displayed excellent reusability, and chitosan-immobilized Maxilact hydrolyzed > 95% lactose in milk after five reuses. Compared to free enzymes, the immobilized enzymes are more suitable for cost-effective industrial production of low-lactose milk due to improved thermal activity, lactose hydrolysis efficiencies, and reusability.


Assuntos
Enzimas Imobilizadas/metabolismo , Lactose/metabolismo , beta-Galactosidase/metabolismo , Alginatos , Animais , Aspergillus oryzae/enzimologia , Quitosana , Estabilidade Enzimática , Tecnologia de Alimentos , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Kluyveromyces/enzimologia , Leite/classificação , Temperatura , beta-Galactosidase/química
16.
Appetite ; 134: 162-171, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30550891

RESUMO

Due to the decrease in fluid milk consumption as a beverage in the United States, the importance for dairy industry stakeholders to understand attribute preferences for consumer segments has increased. This paper uses a representative sample of U.S. residents to determine shopping behavior and a Best-Worst experimental design to examine consumer preferences for select milk attributes. The Random Parameters Logit model revealed the largest preference shares were for price (19.1%), fat content (17.6%), and humane handling (16.1%). Segmentation of the respondents was analyzed using a Latent Class Model, and the demographics of segments were analyzed by probabilistic assignment. This contribution, which may be applied to other products, allows for a detailed understanding of consumer preferences for fluid milk. Demographics such as gender and age were not statistically different across the five classes for this topic, unlike shopping behavior. Class 2 was named "The Balancing Act" due to respondents' balance between animal welfare aspects and the physical characteristics of milk. Class 5 was dubbed "Value and Volume" due to large preference shares for price and container size. A lower percentage of respondents in "The Balancing Act" (12.2%) reported purchasing fat-free skim milk when compared to the percentage of respondents in "Value and Volume" (18.6%). Due to the large preference shares for traditional milk attributes, Class 3 was named "Traditional Milk Shoppers." A higher percentage of respondents in "Value and Volume" also reported always reading the information on meat, egg, or milk products when compared to "Traditional Milk Shoppers" (12.2%). Although price is still important to many consumers, certain segments have preferences or demand for other attributes that may be satisfied by producers to increase market share or price premiums.


Assuntos
Comportamento do Consumidor , Preferências Alimentares , Leite , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bem-Estar do Animal , Animais , Comércio , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Leite/classificação , Leite/economia , Valor Nutritivo , Inquéritos e Questionários , Paladar , Estados Unidos , Adulto Jovem
17.
Crit Rev Food Sci Nutr ; 59(3): 423-442, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28886248

RESUMO

Dairy foods represent an important sector of the food market for their nutritional qualities and their organoleptic characteristics, which are often linked to tradition and to region. These products are typically protected by labels such as PDO (Protected Designation of Origin) and PGI (Protected Geographical Indication). Real-time PCR (qPCR) is a fundamental tool in "Food Genomics;" a discipline concerned with the residual DNA in food, which, alongside traditional physical and chemical methods, is frequently used to determine product safety, quality and authenticity. Compared to conventional or "end-point" PCR, qPCR incorporates continuous monitoring of reaction progress, thereby enabling quantification of target DNA. This review describes qPCR applications to the analysis of microbiota, and to the identification of the animal species source of milk from which dairy products have been made. These are important aspects for ensuring safety and authenticity. The various applications of qPCR are discussed, as well as advantages and disadvantages in comparison with other analytical methods.


Assuntos
Bactérias/classificação , Laticínios/classificação , Laticínios/microbiologia , Leite/classificação , Leite/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Animais , Bactérias/genética , Búfalos/genética , Bovinos/genética , DNA/análise , DNA Bacteriano/análise , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Cabras/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Ovinos/genética , Especificidade da Espécie
18.
Food Res Int ; 113: 131-139, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30195505

RESUMO

A fast and reproducible protocol for milk Nuclear Magnetic Resonance (NMR) metabolomic fingerprinting was developed, allowing for an accurate discrimination among milk samples from large-scale distribution, as well as among milk sample from different farms located in the same restricted geographical area. Seasonal variations in milk composition and correlations with cows' nutritional patterns are also assessed, underlining relationships between feeding and metabolites. The most important difference was related to the use of silage feeding. This finding is relevant to assess the suitability of milk for different dairy products. A prominent example is parmesan cheese, the preparation protocol of which excludes milk from silage-fed cows.


Assuntos
Fazendas , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Leite/química , Leite/classificação , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Queijo/análise , Laticínios/análise , Dieta/veterinária , Feminino , Estações do Ano , Silagem/análise
19.
J Dairy Sci ; 101(8): 7133-7145, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29778484

RESUMO

This study compared the effects of a grain-based conventional concentrate (GC) and a concentrate based on agro-industrial by-products (BC), fed with grass silage harvested at early (ES) or late (LS) maturity stage, on dairy performance, CH4 and CO2 emissions, and metabolic status of dairy cows. Twenty lactating Nordic Red cows averaging 81 d in milk and 31.9 kg of milk/d pre-trial were assigned to a replicated 4 × 4 Latin square design. Dietary treatments were in a 2 × 2 factorial arrangement. The silages were harvested 2 wk apart from the same primary growth grass ley. The GC was made from oats, barley and wheat, and soybean meal, whereas the BC contained sugar beet pulp, wheat bran, canola meal, distillers dried grains, palm kernel expeller, and molasses. The diets were fed ad libitum as total mixed rations and were formulated from 661 g/kg of silage, 326 g/kg of concentrate, and 13 g/kg of minerals on a dry matter basis. The BC supplied the cows with less energy. Despite this, milk yield and composition were unaffected by concentrate type, except that milk protein was 0.7 g/kg lower in cows fed BC than in those fed GC. These results were accompanied by a 44 g/kg decrease in total-tract digestibility of crude protein and a 54 g/kg increase in neutral detergent fiber digestibility for cows fed BC. Cows fed ES on average consumed 2 kg/d more dry matter and yielded 3.5 kg/d more milk, 149 g/d more protein, and 141 g/d more fat than cows fed LS. There were few interaction effects between concentrate and silage sources on daily intake and dairy performance. However, edible feed conversion ratio (human-edible output in animal/potentially human-edible feed) showed greater improvements with ES than LS when replacing GC with BC. Feeding diets with late-cut silage generally reduced digestibility and energy utilization efficiency, but improved N utilization efficiency. Feeding LS also led to greater CH4 yield and CH4/CO2 ratio, and higher plasma concentration of nonesterified fatty acids. Plasma parameters reflecting energy metabolism and inflammation were all within the normal ranges, indicating that the cows were in good health during the experiment. In conclusion, a conventional concentrate can be replaced by agro-industrial by-products without compromising production in early lactation dairy cows. However, silage maturity has a stronger effect on the production traits of dairy cows than type of concentrate.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Bovinos/metabolismo , Dieta , Leite/classificação , Poaceae , Animais , Digestão , Grão Comestível , Feminino , Lactação , Rúmen , Silagem , Zea mays
20.
J Dairy Res ; 85(2): 222-225, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29785908

RESUMO

The aim of the studies reported in the Research Communication was to develop a rapid spectroscopic technique as an alternative method for the classification and discrimination of milk sources by Fourier transform infrared spectroscopy (FTIR). Cow, sheep and water buffalo milk samples were collected from various local milk producers in Istanbul, Turkey. In addition, various brands of packaged milk were purchased locally. Spectrums were obtained according to milk species origin and binary mixtures prepared in increments of 10% (10, 20, 30, 40, 50, 60, 70, 80 and 90%) for each sample analysed in FTIR spectroscopy. A successful milk species (cow, sheep, and water buffalo) discrimination and classification were achieved utilising Hierarchical cluster and principle component analyses (PCA) on the basis of Euclidean distance and Ward's algorithm. Amide-I (1700-1600/cm) and Amide-II (1565-1520/cm) spectral bands were used in the chemometric method. The results of the study indicated that adulteration of milk samples can be quantitatively detected by the FTIR technique in a short time with high accuracy. In conclusion, this method could be used as a new alternative technique for routine analysis in authenticity control of milk species origin.


Assuntos
Búfalos , Bovinos , Contaminação de Alimentos/análise , Leite/química , Ovinos , Espectroscopia de Infravermelho com Transformada de Fourier/veterinária , Animais , Feminino , Leite/classificação , Proteínas do Leite/análise , Análise de Componente Principal , Especificidade da Espécie , Turquia
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