scholarly journals Improvement Of Camel Milk Microbial Loads By Activation Of Lactoperoxidase Enzyme System During Different Storage Temperature

2020 ◽  
Vol 3 (2) ◽  
pp. 1-9
Author(s):  
IEM El Zubeir ◽  
Keyword(s):  
Shelf Life ◽  
Storage Temperature ◽  
Enzyme System ◽  
Raw Milk ◽  
Camel Milk ◽  
Research Center ◽  
Milk Samples ◽  
Fresh Milk ◽  
Keeping Quality

This study was designed to investigate the effect of using the recommended FAO Lactoperoxidase Enzyme System (LPS) on improving the keeping quality and increasing the shelf life of raw milk from camels at different stages of lactations. Fresh milk samples were obtained after morning milking from Camel Research Center of Khartoum University.

scholarly journals Influence of the microbiological quality of raw milk on the shelf life of pasteurized milk

2019 ◽  
Vol 40 (4) ◽  
pp. 1469
Author(s):  
José Carlos Ribeiro Júnior ◽  
Aline Marangon de Oliveira ◽  
Fernando Godoi Silva ◽  
Lorena Natalino Haber Garcia ◽  
Cátia Maria de Oliveira Lobo ◽  
...  
Keyword(s):  
Shelf Life ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Poor Quality ◽  
Pasteurized Milk ◽  
Microbial Counts ◽  
Legal Standards ◽  
Milk Samples ◽  
Brazilian Standard

The dairy industry strives to produce high quality products with high nutritional value as well as to meet the legal standards for longer shelf life. However, these goals are made unfeasible by the poor quality of raw milk produced in some regions of Brazil. Others Brazilian dairy regions, however, already succeed in producing milk with low microbial counts, such as the municipality of Castro, Paraná state, designated as the ‘Brazilian dairy capital’. In order to evaluate the effect of raw milk quality on microbial counts during the shelf life of pasteurized milk, samples were collected from two dairy regions of Paraná: the northern and Castro region, characterized by milk production with high and low microbiological counts, respectively. Samples were experimentally pasteurized and the total microorganism counts were analyzed for 18 days at 7°C, using the Brazilian standard microbiological count limit for pasteurized milk (8 x 104 CFU/mL) as the end of the shelf life. Low microbiological counts in raw milk (Castro) resulted in significantly lower counts shortly after pasteurization and over the entire shelf life, meeting the pasteurized milk standard for 18 days. The temporal evolution in the counts over 18 days for the milks of high and low microbiological count was similar; however, the disparity between the absolute counts between the regions was significant (p < 0.05). Of the milk samples from northern Paraná, four (44.4%) already had counts higher than that of the legislative limit for pasteurized milk immediately after pasteurization. The others (five) reached the maximum microbiological count limit for pasteurized milk on the 6th day after pasteurization. In contrast, the milk from the Castro region remained below the limit throughout the analysis period. Thus, it can be stated that the microbiological quality of raw milk is directly related to the initial count of microorganisms after pasteurization, and that pasteurized milk produced from raw milk with low microbiological counts complies with the Brazilian legislation for 18 days following thermal processing.

scholarly journals Incidence of psychrotrophic lipolytic bacteria in cow’s raw milk

2009 ◽  
Vol 54 (No. 2) ◽  
pp. 65-73 ◽  
Author(s):  
R. Cempírková ◽  
M. Mikulová
Keyword(s):  
Storage Time ◽  
Storage Temperature ◽  
Raw Milk ◽  
Culture Methods ◽  
Mean Values ◽  
Psychrotrophic Bacteria ◽  
Milk Samples ◽  
Limit Value ◽  
Significant Difference ◽  
Medium Level

The contamination of bulk samples of cow’s raw milk (<I>n</I> = 491) by psychrotrophic lipolytic bacteria (PLiBC), total count of psychrotrophic bacteria (PBC) and mesophilic bacteria (TBC) was monitored for two years on eight dairy farms and the correlations among these groups of bacteria were analysed. An increase in TBC, PBC and PLiBC and in the values of free fatty acids (FFA) was tested experimentally in three milk samples in relation to time (analyses were done in 24-hour intervals until 96 hours) and storage temperature of milk samples (4; 6.5 and 10°C). Bacterial contamination of milk was determined by culture methods in accordance with IDF standards, the values of FFA were determined by an extraction-titration method. These mean values were determined in the set of samples (<I>n</I> = 491): PLiBC 659 CFU/ml, PBC 2 932 CFU/ml and TBC 18 932 CFU/ml. A high correlation was proved between values of PBC and PLiBC (<I>r</I> = 0.87; <I>P</I> < 0.001) while the correlation between TBC and PBC (<I>r</I> = 0.65; <I>P</I> < 0.001) and between PLiBC and TBC (<I>r</I> = 0.59; <I>P</I> < 0.001) was on a medium level. The proportional index <I>p<sub>I</sub></I> for PLiBC/PBC was 0.20, for PLiBC/TBC 0.03 and for PBC/TBC 0.16. In seasonal dynamics a statistically significant difference (<I>P</I> < 0.001; <I>P</I> < 0.05) between the increased values of TBC in the summer season was proved compared to the winter and spring season. The differences in the seasonal variation of PBC and PLiBC values were not significant. Experimental investigation of an increase in the values of tested parameters showed that at temperatures of milk sample storage 4 and 6.5°C TBC did not exceed the permissible hygienic value (100 000 CFU/ml) even after 96 hours while at 10°C it amounted to 90 000 CFU/ml after 48 hours and the limit for TBC was exceeded several times after 96 hours. PBC, which is not inhibited by cold storage to such a large extent, did not exceed the hygienic limit value for PBC (50 000 CFU/ml) even after 96 hours when milk samples were stored at 4°C, but at 6.5°C after 72 hours and at 10°C already after 48 hours the values 6 and 20 times higher, respectively, than the hygienic limit were recorded. A similar trend was observed in PLiBC, which exceeded the hazardous limit (43 000 CFU/ml) at 6.5°C after 96 hours and at 10°C already after 48 hours whereas at 4°C the limit value was not exceeded even after 96 hours. The content of FFA also increased in relation to the storage time and temperature of milk samples but in comparison with the increase in the tested groups of microorganisms the increase in FFA showed a higher correlation with storage time compared to storage temperature. A medium correlation was calculated between PLiBC and/or PBC and FFA content (<I>r</I> = 0.52; <I>r</I> = 0.57; <I>P</I> < 0.001).

The Shelf Life of Pasteurized Fresh Milk Manufactured in Saudi Arabia

1988 ◽  
Vol 51 (12) ◽  
pp. 976-978 ◽  
Author(s):  
JOSEPH S. SALJI ◽  
SUHAYL R. SAADI ◽  
AHMED MASHHADI
Keyword(s):  
Saudi Arabia ◽  
Shelf Life ◽  
Sensory Attributes ◽  
Fresh Milk ◽  
C Storage ◽  
Keeping Quality ◽  
Sensory Qualities ◽  
Standard Organization ◽  
Mold And Yeast

The keeping quality of pasteurized fresh milk was investigated. At 7°C storage, the product conformed to the Saudi Arabian Standard Organization for as long as 7 d and as short as 2 d with ≤10 cfu/ml coliform, ≤10 cfu/ml mold and yeast, ≤50,000 cfu/ml SPC and acceptable sensory qualities. Acceptable sensory attributes with coliform counts of &lt;10 cfu/ml were maintained in the product for 10 d at 7°C. Molds, yeasts and psychrotrophs were instrumental in cutting down the shelf life of the product beyond 10 d at 7°C. The possibility of extending the shelf life from 3 to 5 d should not be denied provided the product is stored at temperatures not exceeding 7°C.

scholarly journals Study on the Extension of Shelf-life by Activation of Inherent Lactoperoxidase System in Raw Cow Milk

2014 ◽  
Vol 7 ◽  
pp. 57-60
Author(s):  
Prashanta Pokhrel ◽  
Suman Kumar Lal Das
Keyword(s):  
Hydrogen Peroxide ◽  
Lactic Acid ◽  
Shelf Life ◽  
Room Temperature ◽  
Raw Milk ◽  
Potassium Thiocyanate ◽  
Cow Milk ◽  
Lactoperoxidase System ◽  
Keeping Quality

Effectiveness of lactoperoxidase in raw cow milk was studied to observe the increase in shelf-life. Lactoperoxidase system was activated within two hours after milking by the addition of hydrogen peroxide and potassium thiocyanate, then milk was kept at different conditions viz. refrigerated condition (5±2)°C, room temperature (25±3)°C and at (35±2)°C. The keeping quality of raw milk was determined by the acidity, which when reached 0.18 % as lactic acid, was considered spoiled. Results indicated that the lactoperoxidase system (LP-s) increased the shelf-life of raw cow milk kept at room temperature (25±3)°C and refrigeration temperature (5±2)°C significantly (p<0.05);however no significant increase in shelf-life was observed between the control and LP-s treated raw milk sample held at (35±2)°C. DOI: http://dx.doi.org/10.3126/jfstn.v7i0.10606   J. Food Sci. Technol. Nepal, Vol. 7 (57-60), 2012   

scholarly journals Prevalence, Risk Factors Associated with Brucellosis and Presence of Pathogenic Bacteria Isolated from Camel Milk in Garissa County, Kenya

2020 ◽  
pp. 42-52
Author(s):  
M. Noor ◽  
V. Rotich ◽  
J. W. Kiarie ◽  
K. Cheruiyot ◽  
J. M. Kagira
Keyword(s):  
Risk Factors ◽  
Pathogenic Bacteria ◽  
Control Strategies ◽  
Raw Milk ◽  
Camel Milk ◽  
Ring Test ◽  
Salmonella Spp ◽  
Cross Sectional ◽  
Factors Associated ◽  
Milk Samples

Aim: The current study was undertaken to assess the prevalence, risk factors of brucellosis and presence of pathogenic bacteria isolated from camel milk in Garrisa County, Kenya. Methodology: The study design was cross-sectional where questionnaires were administered to farmers to assess the risk factors associated with brucellosis. The experimental study was also employed to identify bacteria in milk samples which were collected from 104 camels. Fifty milk samples were obtained from local farms while 54 were from sales point at Garissa market. Further test for brucellosis using milk ring test was also carried out. Results: The overall prevalence of brucellosis in camel milk was 8%. Most (12.5%) of the positive samples were from Dadaab Sub-county while the rest of the positive samples were from Fafi (5.9%) and Balambala (5.9%) sub-counties. All the 54 samples obtained from Garissa market were negative of brucellosis. Of the total (118) bacteria isolates, those from the farm level were 68.6% and from market were 31.2%. The bacteria isolated from the 104 milk samples were Pseudomonas spp. (32.2%), Salmonella spp. (30.5%), Staphylococcus spp (21.2%), Eschericia coli (8.5%) and Shigella spp. (7.6%). The risk factors that significantly (p<0.05) associated brucellosis were: age of lactating camels (higher in camels aged above 20 years), herd size (higher in camels from herd sizes of between 30-50 camels) and herding of camels with other livestock (higher in camels kept with other livestock). Conclusion: In conclusion, a few milk samples from camels in Garissa County were found to have brucellosis and were heavily infected with bacteria which can cause mastitis. Considering that most people in the study area drank raw milk, spread of these bacteria to man is a high possibility and thus animal and public health officers should implement one health disease control strategies.

QUALITY ASSESSMENT OF RAW MILK IN KOSOVO

2018 ◽  
Vol 28 (4) ◽  
pp. 1305-1309
Author(s):  
Emine Uka ◽  
Nexhdet Shala ◽  
Arsim Elshani
Keyword(s):  
Negative Impact ◽  
Raw Milk ◽  
The Other ◽  
Human Consumption ◽  
Monitoring Point ◽  
Milk Processing ◽  
Milk Samples ◽  
Fresh Milk ◽  
Quality Of Milk

Since milk is one of the most consumable products of human consumption and in Kosovo, it is one of the most prosperous agriculture branches and the continued support to farmers from the Ministry of Agriculture, European Commission and USID, through which we will offer knowledge about the quality of this milk. Quality milk production is the ultimate goal and goal of any milk producer and processor. On the other hand, the low quality of milk has a negative impact on all segments of the dairy industry, especially in the fresh milk processing segment.Our work provides testing of raw milk samples taken by farmers who send milk to milk collection points and dairies in order to determine the quality of your milk. As a monitoring point we have received the Vita dairy and Aldi dairy in the period January 2017 - October 2018, and we have presented a comparison of their results.

SOME OBSERVATIONS ON THE BACTERIOLOGICAL KEEPING QUALITY OF MILK PROCESSED BY HIGH TEMPERATURES WITH A 0.6 SECOND HOLDING TIME1 2

1963 ◽  
Vol 26 (10) ◽  
pp. 332-336 ◽  
Author(s):  
D. A. Evans ◽  
Eleanor L. Lachman ◽  
Warren Litsky
Keyword(s):  
Heat Treatment ◽  
Raw Milk ◽  
Plate Heat Exchanger ◽  
Plate Heat ◽  
Milk Samples ◽  
Whole Milk ◽  
Keeping Quality ◽  
Quality Of Milk ◽  
Sterilized Milk

Summary Raw milk was processed through a commercial sized plate heat exchanger at temperatures of 160 F through 260 F with a 0.6 sec hold. Milk samples were collected at increments of 10 F during processing and analyzed for psychrophilic, mesophilic and thermophilic counts initially and at weekly intervals thereafter. All samples were held at 40 F after processing. Results indicated that temperatures of processing at 160 F and 170 F were not sufficient to impart acceptable keeping qualities to whole milk held at 40 F for a period of one week. By comparison, processing temperatures of 180 F through 210 F with 0.6 sec hold appeared to impart to whole milk keeping qualities which were approximately comparable to those observed in milk pasteurized according to present standards. When heat treatment in the range of 220 F through 260 F were used, it was indicated that bacteriological keeping quality of the milk was improved to an extent far beyond that experienced with present day commercial pasteurization. There appeared to be somewhat of a tendency for higher count raw milk related to the level of population in the processed product although the magnitude of this relationship was not clearly defined in all cases. It was evident that this process did not produce “commercially sterilized” milk at the processing temperatures and holding time used.

THE ROLE OF PSYCHROPHILIC BACTERIA IN THE KEEPING QUALITY OF COMMERCIALLY PASTEURIZED AND HOMOGENIZED MILK*

1955 ◽  
Vol 18 (2) ◽  
pp. 32-36 ◽  
Author(s):  
J. C. Boyd ◽  
C. K. Smith ◽  
G. M. Trout
Keyword(s):  
Storage Temperature ◽  
Psychrophilic Bacteria ◽  
Milk Samples ◽  
Keeping Quality

Commercially pasteurized and homogenized milk, collected during the summer, fall, and winter months and stored at 40° F and 33° F, was studied for keeping quality. When the storage temperature was lowered from 40° to 33° F, the keeping quality was found to be extended 11 to 14 days. The keeping quality of the milk stored at 40° F, when based upon the development of psychrophilic bacteria up to the 50,000 per milliliter standard, was lower than when based on the deterioration of flavor to a score of 37. The keeping quality of the milk stored at 33° F was found to be approximately the same when judged by either criterion. The keeping quality of the milk samples collected in the fall and winter was poorer than those collected in the summer. This difference was greater when the samples were stored at 33° F than when stored at 40° F. No oxidized flavors were encountered in these milk samples. The deterioration of flavor was closely associated with the growth of psychrophilic bacteria in all samples.

443. Keeping quality and raw-milk grading: III. Comparison of keeping quality tests and dye tests in milk control (results of a field trial)

1951 ◽  
Vol 18 (2) ◽  
pp. 166-192 ◽  
Author(s):  
A. Rowlands ◽  
Zena Hosking
Keyword(s):  
Methylene Blue ◽  
Raw Milk ◽  
Testing Procedure ◽  
Atmospheric Temperature ◽  
England And Wales ◽  
Milk Samples ◽  
Keeping Quality ◽  
One Year ◽  
Morning Milk ◽  
The Relationship

1. The results discussed in this part of the report were obtained by examination of milk samples taken at approximately fortnightly intervals throughout a period of one year from 298 farms in eight widely separated areas of England and Wales. The samples were examined by the routine resazurin test, the methylene-blue (4½/5½ hr.) test, the methylene-blue (½ hr.) test and the temperature-compensated keeping quality test using clot-on-boiling (c.o.b.) to determine the end-point. For the first three tests, the treatment of the samples and the standards applied conformed to those prescribed officially for these tests in England and Wales. Details are given of the treatment of samples and testing procedure for the temperature-compensated c.o.b. test. With this test two standards, equivalent to a residual keeping quality at 22° C. of 21 and 24 hr. from 9 a.m. on the day of collection of the milk from the farms, for both evening and morning milk were used.2. The results are analysed on the basis of the proportion of farms and of samples passing or failing the different tests, the effect of shade atmospheric temperature on the incidence of failures and the relationship between the standards imposed by the c.o.b. tests and the official methylene-blue (4½/5½ hr.) test.The proportion of farms and of samples passing each test was much higher in winter than in summer and was directly related to the prevailing shade atmospheric temperature. However, a proportion of farms was consistently able to comply with the standards. No more than 5% of the total failures by any test could be ascribed to the 60 (20%) best farms, whereas the 60 (20%) worst farms were responsible for as many as 37–60% of the total failures from the 298 farms.

A survey of the microflora of raw and pasteurized milk and the sources of contamination in a milk processing plant in Addis Ababa, Ethiopia

1990 ◽  
Vol 57 (2) ◽  
pp. 233-238 ◽  
Author(s):  
Tadesse Mahari ◽  
Berhanu A. Gashe
Keyword(s):  
Addis Ababa ◽  
Raw Milk ◽  
Processing Plant ◽  
Pasteurized Milk ◽  
Milk Processing ◽  
Milk Samples ◽  
Keeping Quality ◽  
Thermophilic Organisms ◽  
Sources Of Contamination

SummaryThe microorganisms present in raw and pasteurized milk and the sources of contamination in the milk after it had arrived at the processing plant in Addis Ababa were studied. The lowest count registered for raw milk samples was 4 × 107cfu/ml while the highest was 1 × 109cfu/ml. Pasteurized milk had mesophilic aerobic counts of 7 × 105cfu/ml as it left the pasteurizing unit, but the population increased 2- to 4-fold as a result of subsequent contamination. Of the total counts in raw milk, psychrophilic, thermoduric and thermophilic organisms made up 98·l, 1·4 and 0·5% respectively. In pasteurized milk, the amounts were 53·0, 39·5 and 7·5% respectively. Samples of milk pasteurized in the laboratory contained only 74·5% thermoduric and 25·5% thermophilic organisms. The isolates mostly belonged to the generaBacillus, Streptococcus, Lactobacillus, Arthrobacter, Alcaligenes, AeromonasandPseudomonas. Cocci were more predominant than rod-shaped bacteria. Of the rod-shaped bacteria, 73% were Gram-negative. The utensils holding the raw and pasteurized milk and the plastic sheets used for bagging the pasteurized milk contributed unusually high numbers of bacteria which were either thermoduric or thermophilic. More isolates were obtained from the pasteurized than the raw milk. The keeping quality of the pasteurized milk was found to be much lower than that of the laboratory-pasteurized milk.

Sign in / Sign up

Export Citation Format

Share Document