Bulk Raw Milk Research Articles

Analysis of the hard rennet cheese microbiota at different stages of the technological process

The purpose of the research was microbiological screening using MALDI-TOF technology starting from bulk raw milk to the finished dairy product and analyzing microorganisms that were being detected during the technological process of production of Ukrainskyi hard rennet cheese and which were clinically significant for human and animal health. Methods. Microbial detection was performed by accumulation and inoculation using the sector inoculation method on differential media for aerobic and anaerobic microorganisms with further MALDI-TOF identification. Sampling was carried out at 7 stages of cheese production: starting from bulk raw milk to bactofugation, after bactofugation to a mixture normalized in fat content, a pasteurized mixture, a mixture prepared for coagulation, cheese after pressing, and cheese after maturation. Microflora studies were repeated three times, with 405 samples examined. Microbiological studies of Ukrainskyi hard rennet cheese using Maldi TOF technology starting from raw materials to finished dairy products showed the presence of microorganisms at all stages of production – from bulk milk to the finished product. During the entire period of experiments, 43 species of various microorganisms have been isolated and identified. However, the number and individual types of microorganisms differed at different stages of production. Some microorganisms that have been isolated in raw milk are also found in the final product, such as Acinetobacter baumannii and Escherichia coli. In total, 18 types of microorganisms have been isolated and identified in the final product – hard rennet cheese, including Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli, which are of particular concern in the context of safe consumption of this cheese.

Regulated and Emerging Mycotoxins in Bulk Raw Milk: What Is the Human Risk?

Mycotoxins are abiotic hazards whose contamination occurs at the pre- and post-harvest stages of the maize value chain, with animal exposure through contaminated feed leading to their excretion into milk. Currently, only aflatoxin M1 is regulated in milk products. Since feed materials and complete feed present a multi-mycotoxin composition and are the main mycotoxin source into milk, it is important to recognize the occurrence of multiple toxins and their co-occurrence in this highly consumed food product. The aim of this study was to determine the content of regulated and emerging mycotoxins in milk samples, which allowed for evaluating the occurrence and co-occurrence patterns of different mycotoxins known to contaminate feed materials and complete animal feed. Human exposure considering the occurrence patterns obtained was also estimated. Aflatoxins, fumonisins, zearalenone, and emerging mycotoxins were among the mycotoxins found to be present in the 100 samples analyzed. Concentrations ranged from 0.006 to 16.3 μg L-1, with no sample exceeding the AFM1 maximum level. Though several mycotoxins were detected, no exceeding values were observed considering the TDI or PMTDI. It can be concluded that the observed exposure does not pose a health risk to milk consumers, though it is important to recognize vulnerable age groups.

Macroelement Seasonal Variations in Latvian Organic Milk

Abstract Consumer perception of organic milk is associated with the assumption that organic milk differs from conventionally produced milk. The aim of the present study was to analyse calcium, magnesium, and phosphorus concentration in organic milk in the context of the season. The study was conducted from November 2019 to the end of October 2020. Over a year, raw bulk milk samples were collected and analysed. The milk for the study was supplied by two organic farms located in Latvia. Cows received a total mixed ration consisting of high moisture maize silage, grass silage, etc. The chemical composition of the total mixed rations was analysed, as well as fat, protein, lactose, milk solids non-fat, and total solids, calcium, phosphorus, and magnesium content in organic milk were determined. Seasonal variation in milk composition was observed. The average calcium concentration in our study was 107.96 ± 9.61 mg·100 g−1 with a lower average concentration 97 mg·100 g−1 in organic milk in March. The concentration of calcium, phosphorus, and magnesium was higher in organic milk during the spring–summer season. The sale of organic milk is growing in Latvia, and the presence of a favourable level of calcium in organic milk during the whole year should be reached, providing calcium concentration in cow’s milk around 120 mg·100 g−1 throughout the lactation period. Milk and milk products are an important part of daily nutrition, recommended to every consumer due to their wholesomeness and calcium concentration. Evaluating the bone health data of the Latvian population, 100 ml of milk consumption should provide at least 15% of the recommended daily intake of calcium.

Some Variation Factors of Freezing Point in Camel Milk.

The freezing point degree of milk (FPD) is a classical indicator of cow milk quality. In camel milk, few references are available in the literature regarding the main factors of variation. In the present paper, two methods of FPD determination were used: the Reference method (RM) (using Cryostar) and the Express method (EM), using a milk analyzer (Milkoscan-FT1). The RM was used to determine FPD in 680 bulk raw or pasteurized camel milk samples. Regarding EM, 736 individual milk samples, 1323 bulk samples, 635 samples of pasteurized milk and 812 samples of raw milk used for cheese making were available. The variability of FPD was investigated according to month, lactation stage, milk composition, milk production and microbiological status. Correlations between methods were explored. FPD was highly correlated with most of the milk components and tended to decrease in cases of high contamination by coliforms or high total flora count. However, the weak significant correlations between the two methods indicated the necessity to specifically calibrate an automatic milk analyzer for camel milk.

Mycotoxins in Raw Bovine Milk: UHPLC-QTrap-MS/MS Method as a Biosafety Control Tool.

Mycotoxins are compounds produced by several fungi that contaminate agricultural fields and, either directly or by carry-over, final food products. Animal exposure to these compounds through contaminated feed can lead to their excretion into milk, posing threats to public health. Currently, aflatoxin M1 is the sole mycotoxin with a maximum level set in milk by the European Union, as well as the most studied. Nonetheless, animal feed is known to be contaminated by several groups of mycotoxins with relevance from the food safety point of view that can be carried over into milk. To evaluate the multi-mycotoxin occurrence in this highly consumed food product it is crucial to develop precise and robust analytical methodologies towards their determination. In this sense, an analytical method for the simultaneous identification of 23 regulated, non-regulated, and emerging mycotoxins in raw bovine milk using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was validated. A modified QuEChERS protocol for extraction purposes was used, and further validation was performed by assessing the selectivity and specificity, limits of detection and quantification (LOD and LOQ), linearity, repeatability, reproducibility, and recovery. The performance criteria were compliant with mycotoxin-specific and general European regulations for regulated, non-regulated, and emerging mycotoxins. The LOD and LOQ ranged between 0.001 and 9.88 ng mL-1 and 0.005 and 13.54 ng mL-1, respectively. Recovery values were between 67.5 and 119.8%. The repeatability and reproducibility parameters were below 15 and 25%, respectively. The validated methodology was successfully applied to determine regulated, non-regulated, and emerging mycotoxins in raw bulk milk from Portuguese dairy farms, proving the importance of widening the monitoring scope of mycotoxins in dairy products. Additionality, this method presents itself as a new strategic and integrated biosafety control tool for dairy farms for the analysis of these natural and relevant human risks.

INFLUENCE OF SOMATIC CELL COUNT IN RAW MILK ON THE QUALITY OF BEATEN CHEESE

The somatic cells count (SCC) is an important indicator of the hygienic condition of milk. In general, any increase is due to infection of the mammary gland with mastitis, which causes a series of unwanted changes in milk composition and dairy products, respectively. The objective of our research was to determine the impact of somatic cell count on physic-chemical parameters (proteins, fats, moisture, dry matter, salt, and titration acidity), yield and sensory evaluation of beaten cheese. The research was conducted over a period of one year on milk processing capacity in the Pelagonia region. A total of 24 samples of raw bulk milk were analyzed, which depending on the somatic cells count were divided into two categories (ЅСС≤400.000/mL and ЅСС≥400.001/mL). Accordingly, raw bulk milks were used for production of beaten cheese. The results obtained from the conducted research indicate the fact that the changes in the somatic cells count have a significant impact on the physico-chemical parameters, yield and sensory scores on beaten cheese. High SCC above 400.001/mL reduced the percentage of protein, fat, yield and the average sensory score of the beaten cheese.

Lactate dehydrogenase: Detecting high bacterial and somatic cells counts in goats from whole milk samples

The efficacy of using only somatic cell count (SCC) in goats to study the milk quality as a single test has been widely questioned, with total bacterial count being considered as ancillary test in several studies. Therefore, the main objective of this study was to identify new biomarkers of interest that correlate with high SCC and TBC values in milk samples. The concentration of five selected proteins according to their association with infected and injured udders (milk amyloid A, lactoferrin, pentraxin 3, N-acetyl-beta-d-glucosaminidase and lactate dehydrogenase) were determined in bulk raw milk together with SCC and TBC values. Only LDH showed a significant positive correlation with respect to SCC or TBC, no correlation between the other proteins with respect to both parameters were detected. Following, LDH activity and SCC and TBC values were analyzed in a wide diversity of goat milk samples performing a receiver operating characteristic (ROC) curve analysis. LDH showed a significant positive correlation with both SCC and TBC values. LDH activity differed significantly between milk samples with a high and/or low SCC and TBC with a sensitivity that can reach values of 91.3 % and a specificity of 83.2 %. Our results, highlight LDH activity measurement as a biomarker of interest in raw milk for the detection of low-quality milk samples which could potentially be used for the diagnosis of subclinical mastitis in goats.

Prevalence and antimicrobial susceptibility of Listeria spp. isolated from bulk raw milk in north-eastern Poland

Purpose of research: The aim of the study was to determine the presence of Listeria spp. strains in the milk samples obtained from dairy farms in north-eastern Poland and to determine the profile of resistance to antibiotics recommended in the treatment of listeriosis. Material and methods: 500 samples of bulk milk were analyzed. Milk samples were obtained from dairy farms located in Warmia and Mazury region in Poland. Chronic mastitis, requiring frequent and long-term use of antibiotics has been documented in these herds. Isolation of Listeria spp. was performed according to the standard procedure PN-EN ISO 11290-1: 2017-07. Antibiotic resistance testing was performed by the disc diffusion method according to the Clinical & Laboratory Standards Institute (CLSI) recommendations. Results: In total, out of 500 samples of pooled milk, based on biochemical properties, 8 isolates were confirmed as belonging to the genus Listeria (1.6%). The further identification of Listeria strains on the basis of MicrobactListeria12L showed that 3 strains (3/8, 37.5%) belonged to L. monocytogenes species and 5 strains (5/8, 62.5%) belonged to L. innocua species. The analysis of sensitivity to commonly used antimicrobial agents showed that all isolates, both belonging to L. monocytogenes and L. innocua species, were sensitive to ampicillin. Multidrug resistance, defined as resistance to at least three classes of antibiotics, was confirmed among four isolates (50%). Research summary: The studies undertaken revealed that raw milk can pose a risk for public health due to the prevalence of pathogenic Listeria spp. among which multidrug resistant strains are present. It is therefore necessary to rationalize the use of antibiotics and to monitor bacterial resistance in the food production environment.

Hypoglycin A in Cow's Milk-A Pilot Study.

Hypoglycin A (HGA) originating from soapberry fruits (litchi, and ackee) seeds or seedlings from the sycamore maple (SM) tree (related to Sapindaceae) may cause Jamaican vomiting sickness in humans and atypical myopathy in horses and ruminants. A possible transfer into dairy cow’s milk cannot be ruled out since the literature has revealed HGA in the milk of mares and in the offal of captured deer following HGA intoxication. From a study, carried out for another purpose, bulk raw milk samples from four randomly selected dairy farms were available. The cows were pastured in the daytime. A sycamore maple tree was found on the pasture of farm No. 1 only. Bulk milk from the individual tank or milk filling station was sampled in parallels and analyzed for HGA by LC-ESI-MS/MS. Measurable concentrations of HGA occurred only in milk from farm No. 1 and amounted to 120 and 489 nmol/L. Despite low and very variable HGA concentrations, the results indicate that the ingested toxin, once eaten, is transferred into the milk. However, it is unknown how much HGA the individual cow ingested during grazing and what amount was transferred into the bulk milk samples. As a prerequisite for a possible future safety assessment, carry-over studies are needed. Furthermore, the toxins’ stability during milk processing should also be investigated as well.

Detection of Antibiotic Residue in Raw Bulk Milk in Tiyo and Digelu-Tijo Milk Shades of Arsi Zone, Ethiopia

Across-sectional study was conducted from October 30/2017-July 30/2019 to determine antibiotic residues in raw bulk milk in Tiyo and Digelu-Tijo milk shades. Qualitative analysis by using Delvotest SP was conducted to screen antibiotic residues. A total of 125 milk samples were collected for antibiotic screening test. From 125 milk samples screened 12% 15/125 were positive for antibiotic residues. The prevalence was associated with presence of mastitis, history of use of antibiotics for the treatment of disease in their farms and herd size. The higher prevalence of residues was found in the dairy farms with higher prevalence of mastitis that uses antibiotics commonly for the treatment of mastitis and other disease. The residue occurrence was also higher in dairy farm owners who use antibiotics by themselves for the treatment and prevention of dairy cattle disease than consulting to veterinary for the treatment of the infected animals. The prevalence were statistically significant at (p<0.05). Attention has to be paid to the presence of drug residues in milk by producers, processors and consumers to be aware about the health impact of consumption of antibiotic residue with milk. Finally the use of effective enforcement of milk quality and safety standards is essential to provide the public with safe and wholesome animal product particularly milk and milk products. Keywords: Antibiotic screening, milk shad areas, delvotest SP Assay DOI: 10.7176/FSQM/107-03 Publication date: April 30 th 2021

Physicochemical Composition, Antioxidant Status, Fatty Acid Profile, and Volatile Compounds of Milk and Fresh and Ripened Ewes' Cheese from a Sustainable Part-Time Grazing System.

We conducted the first nutritional analysis of dairy products from the traditional Roja Mallorquina sheep breed. Samples of bulk raw milk were taken twice a month from December 2015 to March 2016 from sheep fed using a part-time grazing system, and fresh soft (FC, n = 8) and ripened (RC, n = 8) cheeses were made. The variability in vitamins, total phenolic compounds (TPC), total antioxidant capacity (TAC), and fatty acid (FA) content was influenced by the cheese-making process (differences between the cheese and the original milk) and by the type of cheese-making technology (mainly related to heating, the use of starter culture, and ripening). The most notable physicochemical characteristic of the cheeses was low fat content (24.1 and 29.6 g/100 g for FC and RC). Milk and RC were characterised by major concentrations of retinol (211.4 and 233.6 μg/100 g dry matter (DM), respectively) and TPC (18.7 and 54.6 μg/100 g DM, respectively), while FC was characterised by major concentrations of retinol (376.4 μg) and α-tocopherol (361.7 μg). The fat-soluble components of the FC generally exhibited better nutritional value for human health than those of the milk and RC, with a higher level of retinol and α-tocopherol; lower values for saturated FA, atherogenic, and thrombogenic indices; and higher levels of monounsaturated FA, polyunsaturated FA, n-3, and n-6. Acids, alcohols, and ketones comprised almost 95% of the volatile compounds detected. Acetoin and products of lactose and citrate metabolism played an important role in the development of the aromatic attributes of both kinds of cheese. This preliminary study can contribute to add value to these traditional products according to healthy nutritional criteria and supports the implementation of strategies to promote their commercialisation and obtain product labelling as “pasture-fed” or specific marks.

Evaluation des résidus de tétracyclines et de bêta-lactamines dans le lait de vache produit au Centre Bénin

L’objectif de cette étude a été d’évaluer la présence des résidus de tétracyclines et de bêta-lactamines avec le kit Twinsensor (KIT 020) dans le lait cru des vaches élevées dans les exploitations bovines sédentaires installées dans huit communes du département du Zou et une commune du département des Collines au Centre Bénin. Au total, 261 échantillons de lait cru de tank ont été collectés à raison de trois prélèvements par élevage réalisés à deux jours d’intervalle. Les proportions d’échantillons de lait positifs aux résidus de tétracyclines et de bêta-lactamines par commune ont varié respectivement de 1,4 % à 100 % et de 22,2 % à 100 %. Tous les échantillons de Zakpota étaient positifs aux tétracyclines, alors que dans les huit autres communes moins de 50 % des échantillons étaient positifs à cette famille d’antibiotiques. Les plus fortes proportions de lait (100 %) positif aux résidus de bêta-lactamines ont été observées à Abomey, Agbangnizoun, Dassa-Zoumè, Djidja et Zakpota. Etant donné que les limites de détection des tétracyclines et des bêta-lactamines par la méthode qualitative utilisée étaient inférieures aux limites maximales de résidus recommandées par l’Union européenne, les échantillons positifs devraient être confirmés par un test physicochimique. Néanmoins, le mode de suivi sanitaire et de traitement des animaux dans la zone d’étude pourrait être amélioré pour préserver la santé des consommateurs de lait.

Разработка способа определения в сухом молоке соотношения относительных долей аллелей гена ϰ-казеина

Introduction. High-quality dairy products depend on the properties of raw materials. Milk is the basic raw material for all dairy products. Its quality is subject to requirements of biological safety, and its physicochemical and technological properties comply with strict indicators. ϰ-casein gene is a basic milk protein. Its allelic variants affect milk productivity, as well as its composition and technological properties, e.g. cheeseability and heat resistance. The research objective was to develop a new method for determining the ratio of the relative proportions of selection-significant kappa-casein gene alleles in bulk cow’s milk powder by means of molecular genetics and bioinformation system. The method can help to test raw materials for further processing rationality.&#x0D; Study objects and methods. The research included a genetic analysis of samples of bulk whole milk powder, bulk powdered skimmed milk, and bulk raw milk. The developed method involved DNA extraction, combined PCR-RFLP technique, electrophoretic results, and analysis detection of information data using new mathematical algorithms and software.&#x0D; Results and discussion. The ratio of the relative proportions of the kappa-casein gene alleles in milk powder was determined using primer sets JK5 and JK3, as well as restriction endonuclease HinfI for PCR-RFLP analysis. The experiment showed satisfactory reproducibility and interpretation of the obtained data. The program provided a ratio calculation of the kappa-casein gene alleles relative proportions in the studied milk powder samples, expressed as a percentage of the A allele proportion with additional indication of the absolute and relative errors. It also placed the information block of the generated numerical indicators into the percentage scale.&#x0D; Conclusion. The developed methodology was implemented by a set of laboratory procedures. The new specialized program “Calculation of the relative proportions ratio of ϰ-casein alleles in bulk milk” is on open access. It provides a correct and prompt data interpretation, generated during the analysis of dry milk raw materials of bulk origin.

Milk-borne bacterial health hazards in milk produced for commercial purpose in Tigray, northern Ethiopia

BackgroundMilk being a suitable medium for bacterial growth, it can serve as a source of bacterial contamination. Pathogenic bacteria in milk pose a serious health threat to humans and constitute about 90% of all dairy-related diseases. However, there are few studies that examined the health hazards of raw milk consumption in Ethiopia. Therefore, the objective of this study was to assess the prevalence of bacterial contamination and associated factors in milk produced for commercial purpose in Tigray region, northern Ethiopia.MethodsThis study used a cross-sectional study design, selected 315 persons (168 cafeterias, 96 dairy farms, and 51 milk vendors) for interview and collected the same number of bulk raw milk samples using systematic sampling procedure. Data were collected on socio-demographic, farm hygiene and milk handling practices by trained health professionals. Bacterial contamination was defined as total bacterial count (TBC) > 1 × 105, staphylococcus count (SC) > 105, or coliform count (CC) > 102 CFU/ml by culture and the species of bacteria were determined by standard biochemical tests.ResultsFrom the 315 milk samples tested, the prevalence of bacterial contamination was 52% (95% CI: 46.5–57.6). The mean counts of contaminated samples of TBC, SC, and CC were 8.94 ± 0.46 Standard Deviation (SD), 8.52 ± 0.6 SD, and 8.78 ± 0.49 SD log CFU/ml, respectively. The proportion of contamination was significantly lower in milk collected from dairy farms (32/96, 33.3, 95% CI: 24.5–43.2) compared to milk from vendors (33/51, 64.7, 95% CI: 51.4–66.2) and cafeterias (99/168, 58.9, 95% CI, 50.9–76.85). The milk samples were culture-positive for Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, K. oxytoca and Citrobacter freundii.ConclusionsOver half of the sampled raw milk exhibited bacterial contamination with increasing trend from farmers to points of sale. Thus, milk vendors and cafeteria owners should apply good hygienic and sanitation practices during handling of milk; use appropriate, clean containers, and cold chain during milk transportation; and refrigeration of milk during storage.

Hygienic quality and composition of raw sheep's bulk milk samples on selected Slovak farms during year 2018

At the control of raw ewe's milk (REM) quality is a major microbiological criterion to the total bacterial count (TBC). The aim of our work was to determine the incidence of technologically important species of microorganisms in REM in Slovak Republic. At the monitored 28 ewe´s farms, we took bulk milk samples from evening or morning milking in spring, summer and autumn during year 2018. We analyzed nutrients (fat, protein, lactose and urea) and somatic cell count (SCC). We established technologically important microorganisms (MO) of psychotrophic MO, coliform MO, thermoresistant MO, spore-forming anaerobic MO. We have found a gradual increase in milk components, except for lactose, which is apparently related to the increasing cont of somatic cells during the milking period. We found that the TBC in raw sheep's milk complied an average of 132 x 103 CFU.mL-1 per spring (min 34 x 103 CFU.mL-1, max 501 x 103 CFU.mL-1), 300 x 103 CFU.mL-1 in summer (min. 31 x 103 CFU.mL-1, max 640 x 103 CFU.mL-1) and in autumn with an average value of 147 x 103 CFU.mL-1 (min 52 x 103 CFU.mL-1, max 276 x 103 CFU.mL-1). The enormous occurrence of psychrotrophic bacteria was found in one farm in northern Slovakia during spring and summer, in the summer we increased our number to 3 farms, in the autumn of 2 farms. At the other farms we evaluated the average value of 12 x 103 CFU.mL-1 per spring and 28 x 103 CFU.mL-1 in summer, 130.5 x 103 CFU.mL-1 in the autumn. The count of thermoresistent MO achieved 57 CFU.mL-1 per spring, 15 CFU.mL-1 in summer and 33 CFU.mL-1 in the autumn. The presence of spore-forming anaerobic MO in raw ewe´s milk was found during spring at six farms out of 15, but in the summer at just one in 9, in the autumn two farms.

Sivas İlindeki Bazı Süt İşletmelerine Gelen Sütlerin Ağır Metal İçeriklerinin Belirlenmesi

Bu araştırmada Sivas ve yöresinde bulunan 5 süt fabrikasının depo tankından temin edilen 50 adet süt örneğinde ağır metallerden kadmiyum (Cd), bakır (Cu), krom (Cr) ve kurşun (Pb) içerikleri incelenmiştir. Araştırma sonucunda süt örneklerinin Cd, Cu ve Cr içeriklerinin sırasıyla 8,896, 33,69 ve 31,81 µg/kg düzeyinde olduğu saptanmıştır. Süt örneklerin %92‘inde Pb miktarının tespit edilebilir limitin altında, %8‘inde ise 304,1-503,4 µg/kg olduğu belirlenmiştir.

Lipolytic volatile compounds in dairy products derived from cows fed with dried olive pomace

The study was aimed at evaluating the effects of dietary supplementation with dried olive pomace in dairy cows on the development of lipolytic volatile compounds in raw milk and cheese. Twenty dairy cows, homogeneous for milk yield, parity and days in milk, were randomly assigned to a basal diet (CON) and a conventional diet integrated with dried olive pomace (DOP) as 10% of dry matter. After 60 days of treatment, raw bulk milk of CON and DOP groups was sampled and used to produce cheese that was sampled at 1, 7 and 30 days of ripening. Volatile compounds were analyzed by the SPME-GC/MS technique. Dietary treatment influenced C6, C8, C10 and C12 free fatty acids, the short-chain ethyl and methyl esters, many of ketones and γ- and δ-lactones in raw milk. Cheese showed main differences between groups after 7 days of aging. Levels of methyl decanoate and ethyl esters of even fatty acids from C4 to C14, as well as 2-heptanone, 6-dodecen-γ-lactone, octanal and some C9 secondary lipolytic catabolites such as 8-nonen-2-one, 2-nonanone and 2-nonenal were higher in DOP cheese. The γ-dodecalactone, δ-octalactone, 2-octenal and 1-hexanol were higher in the experimental cheese at 30 days of ripening. DOP dietary integration in feeding operations of dairy cows may modify the evolution of volatile compounds derived from lipolysis in milk and cheese toward moldy and peach notes. A sensory evaluation of these changes will be necessary to understand the consumer acceptability that represents an important feedback to drive dairy industry choices.

Bulk tank somatic cell count and associated microbial quality of milk from selected dairy cattle herds in Oyo State, Nigeria.

Improvement of traditional and nomadic milk production through dairy development program in Nigeria requires routine quality and safety monitoring of milk both at herd level and milk collection centers. A total of 411 bulk raw milk samples aseptically obtained from Ibarapa, Oyo and Oke-Ogun industrial milk collection centers were subjected to California Mastitis Test (CMT), Bulk Somatic Cell Count (BSCC) and bacteriological analysis for assessment of quality and safety of milk from the herds. One hundred and seven (26.0%) of the samples were CMT positive, while 74.0% were negative to CMT. The overall mean BSCC, TAC and TCC were 1.27×103 ± cells/mL, 1.12×103± 34 cfu/mL, 97.8±9.8 cfu/mL in the CMT negative milk samples while for the strong positive samples the mean BSCC, TAC and TCC were 4.33×106 ± cells/mL, 2.35×106 ± 453 cfu/mL, 189.3±41.1 cfu/mL respectively; these were higher than the Pasteurized Milk Ordinance acceptable limits. Positive correlation was found between CMT scores and bacterial contamination and between CMT scores and SCC was recorded. About 26.0% of the samples with positive CMT could be considered unsafe due to strong correlation with microbial contamination that could result in milk borne zoonoses and public health hazards. However, a greater proportion (76.9%) of the milk with negative CMT scores could be safe for human consumption after post-harvest pasteurization. Consequently, there is need to improve handling, environmental and milking hygiene; as well as proper herd and udder health management to improve quality and safety of Nigeria dairy products.

Prevalence of Some Pathogenic Bacteria in Farm Bulk Milk in Dakahlia Governorate, Egypt

Keeping the quality and safety of raw milk is a global challenge. Bulk tank milk (BTM) evaluation has been used to detect potential problems in dairy herds related to milk quality. Raw milk is a worthy medium for growth of several microbes that can result in spoilage of the milk product and infections or poisoning ofconsumers. A number of bacteria including Salmonella, E.coli, and Staphylococcus aureus have been detected in raw milk. In the present study, a total number of 100 raw bulk milk samples were collected from dairy farms in Dakahlia Governorate, Egypt and examined microbiologically. Only 4 samples were positive for Salmonella, 31 were positive for E.coli and 57 were positive for Staphylococcus aureus representing 4%, 31%, and 57 % , respectively. Serologically, 3 species of Salmonella were detected while E. coli isolates were subtyped as O8, O119:H6, O156, O55:H7, O125:H21, O128:H2, O26:H11, O111:H2, O91:H21, O103:H2. The PCR confirmed the serological results of salmonella (inva gene), E.coli (Stx1, Stx2, EaeA genes) and S. aureus (nuc gene). So, it is important to protect the milk from microbial contamination through isolation of infected animals, cleaning, and disinfection of cow teats, use of clean milking equipment, and facilities.

Milk quality characteristics of indigenous sheep breeds Boutsko, Frisarta and Karagouniko

In this study, the chemical and microbiological characteristics of ovine milk from three indigenous Greek breeds, Boutsko, Frisarta and Karagouniko were examined, while reared in the semi mountainous areas. The milk yield of each sheep breed was recorded at the early, mid and late stages of lactation for two consecutive years. The average composition of the samples of ewe’s milk used in this study was similar for protein, lactose and total solids among the three; however fat values were significantly lower (p&lt;0.05) in Frisarta milk compared to Boutsko and Karagouniko. Total viable cells of Boutsko and Karagouniko raw milk were lower (p&lt;0.05) than those of Frisarta. Enterobacteria detected in bulk raw milk from Boutsko and Frizarta breeds were in lower numbers (p&lt;0.05) compared to milk from Karagouniko breed. Somatic cells were also counted in lower numbers in milk collected from Boutsko and Karagouniko breeds compared to Frisarta. The percentage of detected as potentially pathogenic bacteria (coagulase negative staphylococci and enterobacteriae) was higher in the milk from Frisarta sheep milk.