Influence of ultrasound application on the microbiota of raw goat milk and some food pathogens including Brucella melitensis

2021 ◽  
pp. 108201322110496
Author(s):  
H Tavsanli ◽  
M Aydin ◽  
Z A Ede ◽  
R Cibik

The aim of the present study was to investigate the detrimental effect of ultrasound application, as an alternative to pasteurization, on raw goat milk microorganisms and some food pathogens including Brucella melitensis. For this purpose, six different ultrasound applications with a power of 20 kHz at 100%, 50% and 10% amplitudes with or without pulsation were practiced. Colour changes as an increase in brightness (L-value) and decrease in yellow colour value (b-value) were determined in either pasteurized or ultrasonified groups. The most efficient detrimental effect on bacteria was obtained at 100% amplitudes (III and IV group). In these groups, decrease of TAMB, coliforms, streptococci, lactobacilli, yeast and mould counts were 6.52, 6.27, 5.31, 5.61, 5.27 and 4.02 log cfu/ml respectively in raw milk. Inactivation of food pathogens Brucella melitensis type 3, Salmonella Typhimirium, Escherichia coli, Listeria monocytogenes and methicilin resistant Staphylococcus aureus inoculated in goat milk was approximately 99%, which was as efficient as HTST and LTLT pasteurization process. Consequently, ultrasound applications can be an alternative to heat processes in dairy since effective bacterial inactivation could be attained in a relatively economic and environmentally friendly way.

2020 ◽  
pp. 6-12
Author(s):  
HÜSNIYE RÜSTEMOĞLU ◽  
AYDIN RÜSTEMOĞLU ◽  
İSA KARAMAN

Brucellosis is one of the most common zoonotic diseases caused by Brucella. The disease is located genital organs in the females of mammals such as cattle, sheep, goats, dogs and pigs and cause to infertility, mastitis, preterm birth, placenta retention and metritis; in men it causes orchitis (gonorrhea inflammation). The bacteria can also spread from animals to humans and cause disease in humans. The aim of this study was to determine the prevalence of Brucellosis in milk collected from villages of Tokat province and districts. For this purpose, 161 cows, 58 sheep and 33 goat milk samples were investigated by Brucellosis agent with Milk Ring Test (MRT) and direct sowing method. At the end of the study, 24 of 161 cow's milk, 20 of 58 sheep's milk and 5 of 33 goat's milk were found to be positive by MRT. Of the 252 raw milk samples, 49 (n = 19.41%) were positive for MRT. Brucella melitensis biotype 3 were isolated from the 2 milk samples after the culturing from 49 samples with positive MRT. It was determined that 2 milk samples isolated from Brucea belong to 2 different sheep from the same herd. Thus, Brucella was isolated in 0.79% of all studied samples, 4.08% of MRT positive samples and 3.45% of sheep milk samples. As a result of our first study with milk collected from the villages and towns of Tokat province and districts, 19.41% of the samples were positive for MRT and 0.79% of the samples were isolated by direct planting method. Thus, in this study, it was determined that there is a certain amount of Bruceila agent in Tokat province and its districts and it shows that dairy products may pose a risk for Brucellosis.


Dairy ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 410-421
Author(s):  
Golfo Moatsou ◽  
Ekaterini Moschopoulou ◽  
Evangelia Zoidou ◽  
Aggeliki Kamvysi ◽  
Dimitra Liaskou ◽  
...  

The aim of the present study was to assess the effects of different flow-through heat treatments—68, 73, 78, 85, 100 °C for 16 s—applied to in-line homogenized goat and sheep milk. Alkaline phosphatase (ALP) activity in raw goat milk was 324.5 ± 47.3 μg phenol/mL, and that of lactoperoxidase (LPO) was 199.3 ± 6.7 U/L. The respective activities in raw sheep milk were 7615 ± 141 μg phenol/mL and 319 ± 38.6 U/L. LPO activity was not detected in both milk kinds treated at 85 °C for 16 s. Residual enzyme activities at 73 °C for 16 s with respect to the initial levels in raw milk were higher in goat than in sheep milk. The whey protein fraction of sheep milk was more heat sensitive compared to goat counterpart. Sheep milk rennet clotting time (RCT) was not affected by the treatments, while curd firmness decreased significantly (p < 0.05) at 100 °C for 16 s. Treatments more intense than 73 °C for 16 s increased the RCT of goat milk significantly but inconsistently and decreased curd firmness significantly, while yoghurt-type gels made from 73 °C or 78 °C for 16 s treated goat milk exhibited the highest water-holding capacity.


Author(s):  
Alina NASALEAN ◽  
Laurentiu OGNEAN ◽  
Sergiu MUNTEAN ◽  
Stefana BALICI ◽  
Horea MATEI

The milk’s proteins provide nutritional and biologically active values, essential in human and animal nutrition. In the case of goat milk, the proteins’ concentration and quality represent basic indices for the evaluation of the nutritional and biologically active values. The proposal is to comparatively analyse the protein profile of milk. The milk was collected from two different breeds: French Alpine and Romanian Carpathian. During March and April 2016 there were collected samples of raw milk in hygienic and sanitation conditions. There were two lots: first lot has 10 Carpathian goats and the second lot has 10 Alpine goats. The protein composition of goat milk was established with SDS-PAGE, after the evaluation of the total proteins’ concentration with the Bradford method. The quantitative and percentage data obtained with electrophoresis revealed few differences between those 8 identified protein fractions. Between those two lots, regarding the levels of β-CN, k-CN and β-lactoglobulines there were significant differences. The other protein fractions have values almost identical. Statistical analysis of obtained data shaped the differences in the protein profile at those two breeds. Based on those differences it is to note the superior potential of the Alpine breed regarding the content in biologically active milk proteins. Regarding the obtained data, this study brings new contributions for the evaluation and analysis of protein profile as a nutritive and biologically active component of goat milk, confirming its character as a functional aliment.


1958 ◽  
Vol 25 (1) ◽  
pp. 32-51 ◽  
Author(s):  
Peggy B. Taylor ◽  
L. F. L. Clegg

The determination of apparent lactic acid has been used as a basis for a rejection test for raw milk. The method consists of precipitation of milk proteins with barium chloride, sodium hydroxide and zinc sulphate, and the addition of ferric chloride to the filtrate to produce the yellow colour of ferric lactate. Lactic acid is not solely responsible for the production of the yellow colour, which, nevertheless, gives a good relationship with keeping quality of milk (measured as hours to the C.O.B. end-point at 22° C.) and the values have been expressed as ‘apparent lactic acid’.The relationship of winter and summer milks to keeping quality has been studied, and a value of 0·03% apparent lactic acid in milk is equivalent to an average keeping quality of 5¾ and 8½ hr. for winter and summer milks, respectively. A value of 0·03% is recommended as the earliest value of apparent lactic acid at which milk could be rejected.The apparent lactic acid in colostrum and late-lactation milk and in milk from cows suffering from mastitis has been determined, and only in late-lactation milk were the values found to be significantly higher than usual in fresh raw milk, and an inverse relationship between yield and apparent lactic acid is suggested.Permanent glass matching disks have been prepared for use in a Lovibond comparator. This permits the intensity of the yellow colour produced with 1% ferric chloride to be determined and the apparent lactic acid in milk estimated.Grateful acknowledgement is made to the management and staff of the Dairy Department of the Reading Co-operative Society and the Farmer's Clean Milk Dairy, Reading, and local milk producers for supplying samples for experiments; to the N.M.T.S. staff in Reading for help in finding suitable farmers, and to the Dairy Husbandry Department of the N.I.R.D. for information about and samples of abnormal and late-lactation milk. Our particular thanks are due Miss Marie Gruber for technical assistance, to Dr N. J. Berridge for the suggestion and help on the work on pH change as an indication of keeping quality (given in the appendix), and to Dr A. T. R. Mattick for the advice given in this work.


2021 ◽  
Vol 794 (1) ◽  
pp. 012104
Author(s):  
Tota Pirdo Kasih ◽  
Dave Mangindaan ◽  
Afifah Septia Ningrum ◽  
C Sebastian ◽  
D Widyaningrum

Author(s):  
Mourad HAMIROUNE ◽  
Sounia DAHMANI ◽  
Zineb KASMI ◽  
Abdelhamid FOUGHALIA ◽  
Mahmoud DJEMAL

This research was conducted to study the key physicochemical parameters of samples of raw bovine and goat milk collected in the steppic region of Djelfa. One hundred and six samples of raw milk were collected from April 2018 to May 2018, at points of sale and analyzed. The results showed that cow’s milk had 3.66±0.89% fat, 11.4±1.56% solid not fat, 4.35±0.61% protein, 6.35±0.89% lactose and a density of 1.0360±0.0056 with a freezing point of -0.380±0.053 °C. While goat’s milk had 3.43±0.65% fat, 10.2±0.92% solid not fat, 3.88±0.36% protein, 5.66±0.52% lactose and a density of 1.0317±0.0035 with a freezing point of -0.348±0.044 °C. This proves that cow’s milk has a slightly higher physicochemical quality than goat’s milk. In addition, the present study showed that 100% raw goat milk is wet against 97.1% raw bovine milk. This indicates the presence of cases of fraud requiring disciplinary procedures. Moreover, in the majority of the cases, the storage temperatures of the milk far exceed the values recommended by the Algerian standards (+6°C). It is necessary to establish a program of control and popularization of all the actors of the sector in order to improve the quality and the quantity of raw milk produced.


Author(s):  
I. N. Skidan ◽  
C. Prosser ◽  
I. N. Zakharova

The physicochemical properties of infant adapted milk formulae that affect their tolerability and effectiveness depend on the composition and quality of the raw ingredients, the production process, the storage conditions and the quality control of the finished products. The technology of manufacturing a powdered infant formula includes a variety of methodsfor processing componentsthat make up its composition, including raw milk. This processing is accompanied by a noticeable change in a number of physical, chemical and biological properties of the individual components of milk, their loss, the formation of fundamentally new chemical compounds. The most frequent reactions observed during the heat treatment of milk include the formation of bonds between reactive carbonyl groups of the sugar and the amino groups of amino acids, followed by the appearance of a large number of low- and high-molecular compounds, the so-called Maillard Reaction Products(MRP). The study of MRP in recent years hasincreasingly attracted the attention of medical practitioners because of the discovery of these compounds in infant formula and their potential danger to children’s health. This review provides evidence that powdered infant adapted formulae produced with an original technology based on whole goat milk with a native ratio of the main groups of milk proteins(whey – 20% and casein – 80%) have a minimum potential for unwanted effects associated with MRP.


2019 ◽  
Vol 70 (3) ◽  
pp. 1669
Author(s):  
S. KAMINARIES ◽  
A. SCORDOBEKI ◽  
E. ZOIDOU ◽  
G. MOATSOU

Novel reduced-fat goat-cheese (R) was produced from high-pasteurized milk using Penicillium candidum as an adjunct. A full-fat goat-cheese (F) from pasteurized milk without mold addition was produced for comparison reasons. Physicochemical analyses of the two cheeses were performed through the 14-d period of ripening. The effect of P.candidum on proteolysis of goat-cheese caseins and the production of hydrophilic and hydrophobic peptides during cheese ripening were investigated. To our knowledge, similar results for reduced-fat, mold-ripened, goat-milk cheeses have not been previously reported before. R-cheese exhibited a higher organoleptic score and developed properties similar to Kopanisti, which is a Protected Designation of Origin Greek soft cheese with specific intense flavour manufactured from raw milk without the use of starters. Moreover, R-cheese had significantly higher moisture, protein in dry matter and water soluble nitrogen contents than F-cheese and was less adhesive. The high-pasteurization improved the texture and cheese yield, while the use of P. candidum as an adjunct improved the flavour, increased and accelerated proteolysis in R-cheese. According to the results, the technology for R-cheese employed in the present study can be easily adopted and could be used to produce a reduced-fat goat-cheese.


2016 ◽  
Vol 8 (6) ◽  
pp. 149 ◽  
Author(s):  
Cunfang Wang ◽  
Xinman Lou ◽  
Jianmin Wang

<p>In this study, the fatty acid profile and fat stability for seven consecutive days of raw milk and pasteurized milk from Laoshan goats have been evaluated by gas chromatography-mass spectrometry (GC-MS) after fatty acid methyl ester. The results showed that the concentrations of short chain fatty acids (SCFA) and saturated fatty acids (SFA) significantly increased by 47.36% and 11.68% after pasteurization respectively, while the concentrations of unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) decreased by 26.08%, 26.45% and 22.15% respectively. The C10:0 (5.39%-8.57%), C12:0 (3.13%-5.28%), C14:0 (8.12%-11.87%), C16:0 (25.59%-28.53%), C18:0 (14.60-13.69%) and C18:1 (33.91-24.92%) are the most predominant fatty acids of Laoshan goat milk with significant differences. Moreover, the fat stabillity for seven consecutive days of raw milk and pasteurized milk was detected by sedimentation rate (R). The fat stability in pasteurized milk was more stable than that in raw milk, the sedimentation rate of raw milk and pasteurized milk consisted in a progressive decrease in the seven days by 82.99% and 79.77% respectively. What’s more, significant difference was observed from 1st day to 4th day between raw milk and pasteurized milk, however, there was no significance from 5th to 7th. This is the first report to fully characterize the fatty acid contents and fat stability of Laoshan goat raw milk and its pasteurized milk and it provided a certain theoretical basis for the research and development of goat milk functional product.</p>


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