Potentially pathogenic Staphylococcus aureus and Listeria spp. in Brazilian unpasteurized cheese production / Staphylococcus aureus e Listeria spp. potencialmente patogênicos na produção de queijos não pasteurizados

This study aimed to identify potentially pathogenic microorganisms (Listeria innocua, L. seeligeri, L. ivanovii, L. monocytogenes, Staphylococcus aureus, and several virulence genes) in unpasteurized cheese production in the northeastern region of the state of São Paulo, Brazil. Listeria species were detected in 68 (64.14%) out of 106 samples of bovine feces, swabs from milkers' and cheese handlers' hands, milking buckets, raw milk, whey, water, cheese processing surface,s and utensils. All the samples collected at one farm were contaminated with Listeria spp. L. innocua, L. seeligeri, L. ivanovii, or L. monocytogenes were not detected in the samples collected in this study. A set of 391 Staphylococcus spp. isolates were obtained in these samples, from which 60 (15.31%) were identified as S. aureus using PCR (Polymerase Chain Reaction). S. aureus carrying virulence genes (eta, hlg, seg, seh, sei) were detected in milk, in swabs from cheese handler's hands, whey, milk, sieves, buckets, and cheese. The hlg gene (encodes gamma hemolysin) was detected in all the S. aureus isolates. These findings show that poor hygienic practice is associated with a higher risk of pathogenic bacteria in milk or cheese, providing useful information for public health authorities to increase food safety surveillance and prevent the dissemination of pathogens.

O objetivo desse estudo foi identificar microrganismos potencialmente patogênicos (Listeria innocua, L. seeligeri, L. ivanovii, L. monocytogenes, Staphylococcus aureus e diversos genes de virulência) na produção de queijos de leite cru na região noroeste do Estado de São Paulo, Brasil. Listeria foram detectadas em 68 (64,14%) das 106 amostras obtidas de fezes bovinas, suabes das mãos de ordenhadores e queijeiros, baldes, leite cru, soro, água, superfícies e utensílios da produção de queijos. Todas as amostras coletadas em uma fazenda estavam contaminadas com Listeria spp. L. innocua, L. seeligeri, L. ivanovii, e L. monocytogenes não foram detectadas nas amostras coletadas nesse estudo. Um conjunto de 391 isolados de Staphylococcus spp. foram obtidos das amostras, e desses 60 (15,31%) foram identificados como S. aureus pela PCR (Polymerase Chain Reaction). S. aureus contendo genes de virulência (eta, hlg, seg, seh, sei) foram detectados em leite, mãos dos ordenhadores, soro, utensílios e queijos. O gene hlg (gama-hemolisina)foi detectado em todos os isolados de S. aureus.Esses resultados demonstram que práticas inadequadas de higiene estão associadas com um maior risco da presença de bactérias patogênicas no leite e queijos crus, fornecendo informações para as autoridades de saúde pública para incrementarem a vigilância e prevenirem a disseminação de patógenos.

Validation of a method employing liquid chromatography to identify and quantify glycomacropeptide of casein in raw milk / Validación de un método mediante cromatografía líquida para identificar y cuantificar glicomacropéptido de caseína en la leche cruda

Background: The information on official testing methods, or regulatory methods in Colombia to test whey in milk is limited; this restriction of information goes against the possibility of mitigating the risk of food fraud. Objectives: The validation of an HPLC method to determine casein glycomacropeptide (c-GMP), a protein that countries such as Brazil, Spain, and Ecuador have used as an indicator of raw milk adulteration with whey, was carried out. Methods: A 10mL sample of raw milk is precipitated with 24% TCA using ultrasound, a process followed by filtration. The collected fraction ensured the separation of c-GMP and then injected into the liquid chromatography. Results: A 30 minutes analysis allowed the determination of c-GMP with a retention time of 12.9 ± 0.5 minutes. The performance characteristics method in the validation exercise were: recovery percentage 99.97%, linearity R2> 0.95; % RSD accuracy <5.3%. Conclusion, the method exhibits desirable attributes for the intended purpose

Antecedentes: En Colombia la información de dominio público en metodologías de análisis de lactosuero en leche es limitada, restringiendo la posibilidad de acceder a ellas para mitigar el riesgo de fraude alimentario. Objetivos: Se realizó validación de un método por HPLC para determinar en leche cruda c-GMP, proteína usada como indicador de adulteración en países como Brasil y Ecuador. Metodos: Una muestra de 10mL de leche cruda es precipitada con TCA al 24% empleando ultrasonido, proceso seguido por filtración. La fracción recolectada aseguró la separación del c-GMP para luego inyectar al cromatógrafo líquido. Resultados: La determinación de c-GMP permitió el análisis en 30 minutos con tiempo de retención de 12,9 ± 0,5 minutos. Las características de desempeño del método en el ejercicio de validación fueron: porcentaje de recuperación 99,97%, linealidad R2>0,95; precisión %RSD< 5,3%. Conclusión: el método al final del ejercicio exhibe atributos para el fin previsto

Risk factors associated with intramammary colonization with Mollicutes in dairy cattle from Southeast Brazil / Fatores de risco associados à colonização intramamária por Mollicutes em bovinos leiteiros do Sudeste brasileiro

ABSTRACT: Bacteria of Mollicutes Class are associated with intramammary infection and decrease in milk production. This study investigated the occurrence of Mollicutes and elucidated their risk factors in dairy herds from Southeast Brazil. For this, milk samples from 387 lactation cows from Minas Gerais, Rio de Janeiro and São Paulo States were subjected to the polymerase chain reaction (PCR) to detect Mollicutes. Species of Mycoplasma were investigated in Mollicutes positive samples by PCR, including Mycoplasma bovis, M. alkalescens, M. bovigenitalium, M. bovirhinis, M. arginini and A. laidlawii. An epidemiological questionnaire was applied to collect data on possible risk factors, which were assessed using Pearson's Chi-square test followed by odds ratio (P≤0.05). Mollicutes were reported in 21% (4/19) of the herds and 4% (16/387) of the animals, while 1% (5/387) were positive for M. bovis and 3% (11/387) for M. arginini. All samples were negative to the other agents. Herds with more than 150 animals [OR=3.51 (95% CI 1.11-11.08)], manual milking [OR=9.97 (95% CI 2.80-35.49)] and not-milking animals with mastitis last [OR=6.54 (95% CI 1.92-22.29)] were risk factors. The presence of these conditions may favor intramammary infection by Mollicutes in dairy herds from Southeast Brazil. This is the first report of M. bovis in Rio de Janeiro and M. arginini in the studied states.

RESUMO: Bactérias da Classe Mollicutes estão associadas à infecção intramamária e diminuição da produção leiteira. O objetivo deste estudo foi investigar a ocorrência de Mollicutes e elucidar seus fatores de risco em rebanhos leiteiros do sudeste brasileiro. Para isso, amostras de leite de 387 vacas em lactação dos estados de Minas Gerais, Rio de Janeiro e São Paulo foram submetidas à reação em cadeia da polimerase (PCR) para detectar Mollicutes. Espécies de Mycoplasma foram investigadas nas amostras positivas por PCR, incluindo Mycoplasma bovis, M. alkalescens, M. bovigenitalium, M. bovirhinis, M. arginini e A. laidlawii. Foi aplicado um questionário epidemiológico para a coleta de dados sobre possíveis fatores de risco, que foram avaliados pelo teste de Qui-Quadrado de Pearson seguido de odds ratio (P≤0.05). Mollicutes foram detectados em 21% (4/19) dos rebanhos e 4% (16/387) dos animais, enquanto 1% (5/387) destes foram positivos para m. bovis, 3% (11/387) para m. arginini, sendo todas as amostras negativas para os demais agentes. Rebanhos com mais de 150 animais [OR=3,51 (95% IC 1,11-11,08)], ordenha manual [OR=9,97 (95% IC 2,80-35,49)] e ausência de linha de ordenha [OR=6,54 (95% IC 1,92-22,29)] foram considerados fatores de risco. A presença dessas condições pode favorecer a infecção intramamária por Mollicutes em rebanhos leiteiros no sudeste do Brasil. Este é o primeiro relato de M. bovis no Rio de Janeiro e M. arginini nos estados estudados.

Sensory acceptance and physico-chemical composition of mixed minas frescal cheese / Aceitação sensorial e composição físico-química de queijo minas frescal misto

Buffalo milk presents higher proteins and lipids concentration than cow milk, which provides a better yield in cheese-making production and products with considerable sensory approval. However, buffalo milk is not regularly available throughout the year due to different handling conditions. Thus, to guarantee the supply of buffalo milk dairy products during the year, the addition of bovine milk is an alternative. Therefore, this study aimed to test the effect of a buffalo and bovine milk mixture for the Minas Frescal cheese elaboration by physico-chemical, sensory analysis and obtaining yield. The raw material was analysed for the parameters of acidity, density, fat, total solids and solid-not-fat. There were 3 Minas Frescal cheeses elaborated from 3 formulations: 100% buffalo milk, 100% bovine milk and the mixture of 50% of each milk. The cheeses were submitted to the Gravimetric and Gerber methods to obtain values of moisture and fat, as well as to obtain, indirectly, fat in dry matter. For bovine and buffalo milk, the parameters evaluated (acidity, density, fat, total solids and solids-not-fat) complied with Brazilian legislation and parameters described in the literature. For the bovine, mixed and buffalo fresh cheeses, values were obtained, respectively, for moisture (74.04, 60.93 and 63.61), fat in dry matter (44.35, 42.23 and 46.03) and cheese yield (27, 20.8 and 24.2), indicating a higher yield for the bovine Minas Frescal cheese and higher fat content for the buffalo cheese. The overall acceptance of the mixed Minas Frescal cheese was significantly superior to the bovine and buffalo cheese. The parameters of colour, appearance, texture, flavour and overall acceptance were above 8 points in the hedonic scale ('moderately liked' to 'extremely liked'), and the aroma attribute scored was above 7 ('I enjoyed regularly' to 'moderately liked'). Therefore, the elaboration of Minas Frescal cheese from the mixture of 2 matrices (buffalo and bovine milk) demonstrated technological viability with the potential to meet the demands of the consumer market.

O leite de búfala possui maior porcentagem de todos os componentes tornando-o uma matéria-prima adequada com potencial para fornecer um maior rendimento e qualidade nutricional na produção de queijo. No entanto, o leite de búfalo não está disponível regularmente ao longo do ano devido a diferentes condições de manejo. Assim, para garantir a oferta de produtos lácteos com leite de búfala independentemente da época, a adição de leite bovino pode ser vista como uma alternativa. Logo, este trabalho teve como objetivo testar o efeito da mistura do leite de búfalo e bovino na elaboração do queijo Minas Frescal por meio de análises físico-químicas e sensoriais e obtenção do rendimento economico. A matéria-prima foi analisada quanto aos parâmetros: acidez titulável, densidade, gordura, sólidos totais e sólidos totais desengordurados. Três variedades de queijo Minas Frescal foram elaboradas a partir de três formulações: 100% de leite de búfala, 100% de leite bovino e da mistura de 50% de cada leite. Os queijos foram submetidos aos métodos Gavimetric e Gerber para obtenção de umidade e gordura, bem como, indiretamente, para obtenção de matéria gorda no extrato seco. Para o leite bovino e de búfala, os parâmetros avaliados (acidez titulável, densidade, gordura, sólidos totais e sólidos totais desengordurados) estavam de acordo com a legislação brasileira e parâmetros descritos na literatura. Para os queijos bovino, misto e de búfala, foram obtidos, respectivamente, para: umidade (74,04; 60,93 e 63,61), gordura na matéria seca (44,35; 42,23 e 46,03) e rendimento econômico (27, 20,8 e 24,2) indicando maior rendimento o queijo Minas Frescal bovino e maior teor de gordura para o queijo búfalo. A aceitação global do queijo Minas Frescal misto foi significativamente superior ao do queijo bovino e bubalino. Os parâmetros de cor, aparência, textura, sabor e aceitabilidade global foram acima de 8 pontos (entre "gostei moderadamente" e "extremamente gostei") e o atributo aroma obteve pontuação acima de 7 ("gostei regularmente" para "gostei moderadamente"). Portanto, a elaboração do queijo Minas Frescal da mistura de leite bovino ao búfalo demonstrou potencial para atender as demandas do mercado consumidor.

Occurrence of Carbaryl, DDT and Deltamethrin Residues in Bovine Milk in Chhattisgarh, India and Risk Assessment to Human Health

The aim of this study was to determine the occurrence of pesticide residues in bovine milk and associated health risks in human. To assess the pesticide residues, a total of 200 milk samples were analyzed using High Performance Liquid Chromatography (HPLC) with Photo Diode Array Detector (PDA).The residues of carbaryl, 4’4’ DDT and deltamethrin pesticides were found in the 27.5%, 11% and 5% milk samples, respectively. The spatial distribution of pesticide residues in milk samples indicated that carbaryl was wide spread over the entire study area. The non-significance differences in mean residual concentrations of all three pesticides in cow and buffalo milk samples were recorded. The human health risk assessment in terms of non-carcinogenic and carcinogenic health hazard was calculated based on both lower bound [LB (mean residue levels)] and upper bound [UB (95th percentile level)] limits at current levels of pesticides in bovine milk samples. The estimated average daily dietary intake (EADDI) of studied pesticides was found below the acceptable dietary intake (ADI) for both adult and children, at mean as well as 95th percentile upper bound (UB) levels. The values suggesting lower carcinogenic and non-carcinogenic health risk to adult however children are at greater health risk.Keywords: Bovine milk, carbaryl, deltamethrin

Influencia de las estaciones del año en la composición y la calidad sanitaria de leche bovina del Valle de Lerma, Salta / Seasonal influence on chemical composition and sanitary quality of bovine milk of the Lerma´s Valley, Argentina

Resumen Con el objetivo de conocer la influencia de las estaciones del año respecto de la composición y la calidad sanitaria de leche bovina de la cuenca del Valle de Lerma se llevó adelante el análisis de las muestras de leche remitidas por la industria al Laboratorio de Leche de la Universidad Nacional de Salta durante la primavera (Pr, n:104), el verano (Ve, n:131) y el invierno (In, n: 118) de los años 2017 y 2019. Se determinó el porcentaje de grasa (% G) y de proteína (% P), el punto de descenso crioscópico (DC) y el recuento de células somáticas/ml (RCS/ml). El análisis estadístico se realizó utilizando el programa InfoStat 2019p. El modelo respondió a un DCA. El % G y P fueron analizados mediante ANOVA. Mientras que para DC y RCS se utilizó ANOVA no paramétrico de Kruskal Wallis. La comparación entre medias fue a través del Test de Tukey (p<0,05). El % G resultó de acuerdo a los estándares establecidos por la legislación argentina en todas las estaciones del año, aunque el valor en el In fue inferior al de Ve (3,49 vs 3,64, p=0,0009). El % P resultó similar en las 3 estaciones, pero por debajo de los estándares nacionales (In: 3,24, Pr 3,26, Ve: 3,26). El DC (°C) si bien fue inferior al máximo adecuado difirió entre el In (-0,522) y la Pr (-0,519) y el Ve (-0,518) (p=0,0023). El RCS en el In y la Pr fue similar (264000 vs. 228000 cel/ml, respectivamente); mientras que en el Ve resultó superior (p=0,0012) mostrando valores promedio mayores (430000 cel/ml) al límite establecido por los estándares nacionales. Al comparar los resultados obtenidos con los estándares de composición química y sanitaria de referencia en Argentina se observa que, salvo los niveles de proteína y el RCS durante el verano, el resto de los parámetros se encuentran conforme a lo establecido en la legislación nacional.

Abstract The aim of this study was to determine the seasonal influence in bovine milk composition and sanitary quality for Lerma Valley basin. Samples sent by dairy industries to National University of Salta Milk Laboratory during spring (Pr, n: 104), summer (Ve, n: 131) and winter (In, n: 118) of the years 2017 and 2019 were analyzed. Fat (% F) and protein (% P) percentages, freezing point (FP) and somatic cell count / ml (RCS / ml) were determined. Statistical analysis was performed using the InfoStat 2019p program. The model responded to a CRD. % F and % P were analyzed by ANOVA, while for FP and SCC non-parametric ANOVA from Kruskal Wallis was used. Tukey Test (p <0.05) was used for means comparasions. % F was according to Argentine legislation in all seasons of the year, although ln value was lower than that Su (3.49 vs. 3.64, p= 0.0009). % P was similar in the 3 stations, but below the national standards (Wi: 3.24, Sp: 3.26, Su: 3.26). FP (° C), differed between Wi (-0.522) and Sp (-0.519) and Su (-0.518) (p=0,0023), although values were below the upper range value. SCC (cel / ml) Wi In and Sp was similar (264000 vs. 228000 cel/ml, respectively), while in Su it was higher (p = 0.0012) showing higher average values (430,000 cel / ml) than the limit established by national standards. The results obtained in this study were accord with the chemical and sanitary composition of reference in Argentina, except for protein levels and SCC during the summer.

Atividade antisséptica do óleo essencial de Lippia origanoides Cham. (Alecrim-pimenta) na presença de leite bovino / Antiseptic activity of the essential oil of Lippia origanoides in the presence of bovine milk

Objetivou-se determinar atividade antisséptica do óleo essencial de Lippia origanoides na presença de leite bovino. A composição química do óleo essencial de alecrim pimenta foi determinada por cromatografia gasosa acoplada à espectrometria de massas (CG-EM), sendo detectados 53 compostos, dos quais 16 foram identificados (>0,1% área total). O carvacrol (32,7%), p-cimeno (23%), timilmetil éter, cariofileno (7,98%) e o γ-terpineno (5,40%) foram os componentes mais abundantes. A concentração inibitória mínima para Staphylococcus aureus ATCC 25923 e E. coli ATCC 8739 foi de 60µL/mL, enquanto para Salmonella Choleraesuis ATCC 35640 foi de 90µL/mL. A concentração bactericida mínima foi de 120µL/mL para as três bactérias. Avaliou-se a atividade antisséptica do óleo essencial na concentração de 120µL/mL na presença de leite bovino sobre as mesmas cepas bacterianas. O óleo em estudo apresentou efeito inibitório do crescimento das cepas em diferentes tempos de ação (p<0,05). S. aureus apresentou maiores índices de inibição após 5 min de contato e Escherichia coli e Salmonella Choleraesuis após 15 min. O óleo essencial de alecrim-pimenta revelou ser um potencial antimicrobiano natural, mesmo na presença de matéria orgânica constituída de uma matriz nutricional complexa que é o leite bovino.(AU)

This study aimed to determine the antiseptic activity of the essential oil of Lippia origanoides in the presence of bovine milk. The essential oil chemical composition was determined by gas chromatography-mass spectrometry (CG EM) 53 compounds were detected, of which 16 were identified (>0.1% total area). The carvacrol (32.7%), p-cymene (23%), thymil methyl ether (10.03%), caryophyllene (7.98 %) and γ-terpinene (5.40%) were the most abundant components. The minimum inhibitory concentration for Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 8739 was 60uL/mL, as for this Salmonella Choleraesuis ATCC 35640 was 90uL/mL. The minimum bactericidal concentration was 120µL/mL for all three bacteria. We evaluated the antiseptic activity of the essential oil in the concentration of 120µL/mL in the presence of bovine milk for the same bacterial strains. The oil under study It showed an inhibitory effect of growth of the strains in different action times (p <0.05). S. aureus showed higher inhibition rates after 5 min of contact and E. coli and Salmonella Choleraesuis after 15 min. The essential oil Lippia origanoides proved to be a natural antimicrobial potential even in the presence of organic matter consists of a complex nutritional matrix is bovine milk.(AU)

Analysis of antibiotic residues in milk from healthy dairy cows treated with bovine mastitis ointment using ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry

This study was conducted to analyze penicillin G (PEG), streptomycin (STR) and neomycin (NEO) residues in milk of healthy lactating cows. Milk samples were collected from all four quarters of 12 dairy cows 2–7 days after intramammary infusions of an ointment containing PEG, STR and NEO once (n = 4; group I) or twice (n = 4, group II) daily. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry was used to determine the antibiotic residues in the samples. The correlation coefficient (r 2) of the calibration curves for all antibiotics was > 0.999 and the limits of detection and quantification were 0.002–0.005 µg/mL and 0.007–0.02 µg/mL, respectively. Recovery rates were ranged from 75.5 to 92.3%. In group I, PEG, STR and NEO residues were detected in milk at 2, 3 and 2 days post-treatment, respectively, which were below the maximum residue limit (MRL). In group II, PEG, STR and NEO residues were detected in milk at 2, 3 and 3 days post-treatment, respectively, which were bellow the MRL. These results suggest that a 3-day for milk withdrawal period after the ointment treatment might be sufficient for reduction of the antibiotic residues below the MRL.

GC-MS Determination of Organochlorine Pesticides in Bovine Milk from Tiruchirappalli, South India- A Preliminary Assessment.

The study was aimed to determine the concentrations of organochlorine pesticides (OCPs) in bovine milk (both branded and unbranded) collected from in and around Tiruchirappalli city, Southern India. The results of the present investigation indicated that these milk specimens were found to be contaminated with 7 different pesticides. Mirex (higher incidence), Heptachlor, o,p’-DDD, o,p’- DDE, Aldrin, cis and trans-chlordane were detected in the milk samples. The residues were quantitatively determined using Gas Chromatograph-Mass Spectrometer-Quadrupole on electron ionization (EI) mode. The study showed that unbranded milk samples contained higher concentrations of residues than branded. The derived average daily intake of aldrin and DDT has exceeded WHO’s Acceptable Daily Intake.

Contaminants in milk and impact of heating: An assessment study.

Background: The major contaminants usually encountered in milk and milk products include pesticide residues, heavy metals, and aflatoxin M1 (AFM1). Primarily, milk get contaminated before milching, from the cattle feed, from sources/materials used during the processing of milk as well as improper handling of the milk during the pre- and postprocessing period. Objective: The purpose of this study was to evaluate the effect of household practices on milk contaminants. Materials and Methods: Samples of pasteurized as well as unpasteurized milk (Vendor's milk) were analyzed for AFM1, pesticide residues, and heavy metals. Simulating the household practices, the impact of boiling on these contaminants was assessed. Results: The contaminant Aflatoxin M1 (AFM1) was detected at a concentration ranging from 0.071-0.075 ppb in unpasteurized as well as pasteurized milk samples analyzed during the course of study. Moreover, boiling had no impact on the quantity of AFM1 present in the milk. Pesticides and heavy metal contents were found to be within acceptable limits in all the milk samples tested. Conclusion: Mycotoxins especially aflatoxins in cattle feed and their consequential presence in milk and milk products is a serious concern world over as they are reported carcinogens. These fungal toxins are resistant to high temperatures and may lead to various health hazards. Preventive steps must be taken at each stage to ensure good quality of milk and milk products free from these contaminants. Awareness programs and education for the dairy farmers and milk processors may be helpful in this regard.

Microbiological profile of milk: Impact of household practices.

Background: Milk is susceptible to contamination by many microorganisms including microbial pathogens responsible for causing diseases. Various processes including pasteurization, boiling or storage under refrigerated conditions are undertaken to minimize the microbial contamination of milk. Objective: This study was undertaken with an objective to evaluate the effect of household practices on the microbiological profile of milk. Materials and Methods: Milk samples of pasteurized, ultra heat treated (UHT) as well as unpasteurized milk (Vendor's milk) were collected. The effect of different storage practices and treatments on the microbiological profile (standard plate count (SPC), coliform, E. coli, Salmonella, Shigella, Staphylococcus aureus, yeast and moulds, anaerobic spore count, and Listeria monocytogenes) of milk was studied using National/ International Standard Test Methods. Results: Average SPC in vendor's milk was found very high as compared to pasteurized milk. Coliform, yeast and moulds, E. coli, and Staphylococcus aureus were detected in the samples of vendor's as well as pasteurized milk. Boiling the milk reduces SPC and kills the other microorganisms. Storage of boiled milk under room temperature or refrigerated condition resulted in a similar increase in SPC at the end of 24 h, but storage of un-boiled milk even under refrigerated conditions increased SPC manifold after 24 h. Conclusion: The pasteurization process and hygienic conditions at the milk processing units along with cold chain of milk from suppliers to end users needs improvement. Currently, even pasteurized milk does not match the microbiological standards. It is recommended that milk should be boiled before consumption and refrigerated for storage to improve its shelf life/keeping quality.

Bovine milk usage and feeding practices for infants in India.

Background: Milk and dairy products from animal sources (cow's milk or buffalo's milk) are an important part of Indian diet and its consumption starts at an early age. Objective: The purpose of this study is to understand the processing, storage and modifications carried out before bovine milk is fed to the infants and compare it with recommendations by Health Care Professionals (HCPs). Materials and Methods: The study involved assessments involving HCPs and mothers of children below 1 year of age through both qualitative and quantitative methods. Feeding recommendations by HCPs were assessed through a quantitative method. Results: The children are commonly initiated on bovine milk post 3 months of age. The milk is not covered while boiling in 70% cases and boiled at suboptimal temperature (moderate: 62% or low: 31%). Half of the families store milk outside refrigerators openly in the kitchen or rooms. The milk is modified in the majority of cases (81%) before being fed. Modification of the milk was often done with sugar (85%), followed by water (49%), biscuits, fennel seeds, cardamom or infant cereals before feeding the baby. Addition of water was more prevalent among mothers of infants between 3 and 6 months. HCPs do not advise consumption of bovine milk by infants unless there is no other option available. Conclusion: A clear gap exists between recommended and actual practices for infant feeding in India. There is a huge opportunity to educate mothers on importance of breast feeding and benefits of implementing appropriate processing, storage, and consumption practices of bovine milk.

Equilibrium dialysis studies on the binding of anionic surfactants with bovine milk casein.

The binding process of amphiphile molecules with proteins depends on the experimental conditions, such as protein concentration and surfactant type. The proteins may have different binding characteristics, such as specific and cooperative binding. Specific binding is the most important pathway observed at low surfactant concentration at levels of micromolar unity, while the cooperative process becomes the most important at higher surfactant concentration, close to the critical aggregation concentration. At the levels at which specific binding occurs there is competitivity, i.e., the presence of an additional molecules can be induced hydrophobically or electrostatically depending on the characteristics of the molecular structure and experimental conditions. For instance, electrostatic binding is pH dependent and this factor is important for ionic surfactants.

Determination of Major Bovine Milk Proteins by Reversed Phase High Performance Liquid Chromatography / 分析化学

A RP-HPLC method for the quantification of the six major bovine milk proteins (κ-casein (CN),α_(s2)-CN,α_(s1)-CN,β-CN,Whey,immunoglobulins (Igg) ) is described. Separation and quantification were achieved by a reversed phase analytical column (Agilent Zorbax 300SB-C_8,250 mm×4.6 mm ,5μm) and the gradient elution solvents of 0.1% trifluoroacetic acid (TFA) in water and 0.1% TFA in acetonitrile at a flow rate of 0. 8 mL/min. Column temperature was set at 45℃ and the sample was monitored with photodiode array detector at 214 nm. A linear relationship( r >0. 999) between the concentrations of proteins and peak areas was observed over the concentration range. Recoveries of six target proteins spiked in milk were form 74. 8% to 132.5%. Nine kinds of milks of different brands were analyzed,and the difference of the concentration and relative ration of κ-CN,α_(s2)-CN,α_(s1)-CN,β-CN and Whey were found.