scholarly journals Participation of Microorganisms in Milk and Milk-products Contamination and Safety

2021 ◽  
Vol 3 (2) ◽  
pp. 60-64
Author(s):  
Ali Elshafei

Milk and milk-products represent the main basic nutritional healthy food in the human diet; however, milk is also a favorable source of microbial infection for human health when milk and milk products are consumed without applying hygiene milk practices methods such as pasteurization and other effective methods to avoid contamination risk. The presence of microorganisms in milk could result in spoilage and severe diseases to humans. Several recent preservation systems such as heating, refrigeration, and the addition of safe antimicrobial compounds can be used to reduce the risk of outbreaks of dairy product poisoning. Proper food control programs must be implemented in all countries around the world to ensure the safety of food and dairy products. Investigators reported the importance of applying effective hygiene practices during milking and handling of raw milk to reduce the risk of contamination on the farm and in the milk processing plant in the industry.

2000 ◽  
Vol 46 (12) ◽  
pp. 1108-1114 ◽  
Author(s):  
E C Tondo ◽  
MC M Guimarães ◽  
J AP Henriques ◽  
M AZ Ayub

A dairy product processing plant was studied for 2.5 years to examine contamination with Staphylococcus aureus and try to correlate the source of contamination. Cultures were submitted to an antibiotic susceptibility test (AST) and characterised by Pulsed-field Gel Electrophoresis (PFGE) analysis. Results showed that 35.2% (19/51) of food handlers were asymptomatic carriers of S. aureus, and that 90.4% (19/21) of raw milk sampled was contaminated. Staphylococcus aureus was isolated from only 10 samples among more than 3200 investigated dairy products. No S. aureus contamination was found on machinery. The AST analysis demonstrated sensitivity of tested S. aureus to oxacillin, cephalothin, vancomycin, gentamicin, and sulfamethoxazole/trimethoprim. AST analysis generated eight different phenotypic profiles, but did not allow us to identify the source of contamination in seven of ten final products. PFGE analysis proved to be a sensitive method as it generated 42 different DNA banding profiles among the 48 S. aureus investigated, demonstrating a lack of predominance of endemic strains in the plant, contrary to suggestions raised by antibiotic resistance typing. Based on PFGE genotyping, S. aureus strains isolated from four contaminated final products were similar to four S. aureus isolated from raw milk. Five final products contained S. aureus different from all other strains collected, and one showed similarity to a strain isolated from a food handler. These results suggest contamination by raw milk as the main source of contamination of the final dairy products.Key words: Staphylococcus aureus, dairy products, antibiotic susceptibility, PFGE.


1980 ◽  
Vol 43 (7) ◽  
pp. 536-537 ◽  
Author(s):  
T. A. EL-BASSIONY

A total of 163 samples of milk and milk products (including raw milk, Damietta and Kareish cheese, hard and processed cheese, yogurt, butter and ice cream) were collected from Assiut City markets. Clostridium perfringens was detected in 45.5, 20, 30, 14.3, 20, 10, 50 and 20% of the examined samples, respectively, using SPS agar. With TSN agar, the organism was isolated from 72.7, 20, 30, 28.6, 50, 10, 50, and 30% of the samples, respectively. The mean value of the C. perfringens count using SPS agar was 53.6/ml, 40/g, 60/g, 14.3/g, 30/g, 1.4/g, 25/g and 8/ml of raw milk, Damietta and Kareish cheese, hard and processed cheese, yogurt, butter and ice cream samples, respectively, while the mean values of C. perfringens counts obtained with TSN agar were 76.4/ml, 170/g, 140/g, 42.9/g, 590/g, 2.9/g, 172.9/g, and 109/ml of examined samples, respectively. Milk and dairy products, if improperly handled, provide a means for transmission of C. perfringens to the consumer.


2005 ◽  
Vol 29 (2) ◽  
pp. 67-80
Author(s):  
Bushra I. Al-Kaisie

This study was designed to isolate and identify the type of moulds and theirpercentage of distribution with pathological study of highly moulds isolated from(130)samples were included in this study with divided into (30)samples driedmilk,(30).samples baby food ,(30)samples raw milk , (40) samples dairy products .The results revealed the percentage of infection according to total count ofisolation in raw milk were 100 % dairy product 65 %. The most common fungiisolated from raw milk were Asp.niger of 16.2 % Asp. fumigatus of 15 % Asp.flavusof 13.7 % Pencillium spp. 12.5 % . From dairy products were isolated withpercentage of Asp. Fumigatus 34.9% Geotrichum spp . of 23 % ,Asp. nager of 11.5% . Pathological study was carried out to investigate the clinical signs with grosslyand Histopathological changes inoculated with most pathogenic moulds Asp.fumigatus (30)male white swiss mice were used in this study and divided into fourgroups . The first group were injected I/P with 0.2 ml of Asp. fumigatus containing1X105 spores / ml , 4th group (control)given orally 0.2 ml of PBs.Two mice fromeach treated groups and one from each control group were scarified on week (1,2,3,4).the clinical manifestation of the 1st group were at 2nd week showed dyspnea .Mouldisolated from blood and internal organs at third week , with no isolation from 3rdgroup. The Histopathological observations showed presence of degeneration ,necrosis and diffused granuloma in liver, lung , spleen , kidney and hemorrhage withthrombosis in brain and intestine .


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Linda Valkovska ◽  
Artjoms Mališevs ◽  
Kaspars Kovaļenko ◽  
Aivars Bērziņš ◽  
Lelde Grantiņa-Ieviņa

Abstract Introduction Q fever in dairy cattle has been investigated in Latvia since 2012. In 2015, 10.7% of farms tested positive for the DNA of C. burnetii, its aetiological agent, in bulk tank milk. The presence of C. burnetii DNA and infectious bacteria in dairy products has been assessed in several countries, and because Latvian milk may contain them, parallel assessment in this country is recommended. Accordingly, the present study tested shop and farm retail dairy products from Latvia and included foreign products for comparison. Material and Methods Investigation was carried out of 187 samples of a diverse range of dairy products from 41 Latvian milk producers. Twenty-six comparable samples pooled from Estonia, France, Germany, Greece, Italy, Lithuania, the Netherlands, Poland and Spain were also included. The all-countries total number of fermented milk products was 160. Special attention was paid to products that could be more attractive to children because of their added chocolate, cacao, berry and fruit content. DNA was extracted and amplification of C. burnetii IS1111 was performed using a commercial PCR kit. Results Overall positivity was 60.56%. Domestic products were positive more often (60.96%) than foreign ones (57.69%). Only 26.67% of unpasteurised Latvian cow’s milk samples were positive whereas 76.47% of pasteurised equivalents and 63.13% of fermented milk products were. Sweetened and fruit-containing samples were 71.43% positive. Conclusion The shedding of C. burnetii via milk should be monitored and only milk from healthy animals allowed for sale for direct human consumption without pasteurisation. Raw milk quality and the effectiveness of industrial heat treatment and pasteurisation methods in Latvia and other countries should be carefully assessed to ensure adequate consumer health protection.


Author(s):  
Prasad Patil ◽  
Akanksha Wadehra ◽  
Kanchan Munjal ◽  
Pradip Behare

Currently, much attention is being paid for improving the texture of food by screening the new exopolysaccharides (EPS) producing strains. The aim of the present work was to isolate EPS producing Lactic acid bacteria (LAB) strains from raw milk and milk products samples. Total of thirty eight dahi, lassi and raw milk samples were collected from different villages and towns of Karnal and Delhi District. The samples were plated on milk agar and colonies showing ropy polysaccharides production were subjected to biochemical test. After molecular identification 2 were found as <italic>S. thermophilus</italic>, 2 were <italic>Lb. rhamnosus</italic> and 2 were confirmed as <italic>Lb. fermentum</italic>. Two <italic>S. thermophilus</italic> strains (PD7 and PD11) and <italic>Lb. fermentum</italic> strains (AL6 and AD3) showed better curdling pattern, acidity, exopolysaccharides production, and sensory properties. These cultures can be used for manufacture of indigenous fermented milk products.


2016 ◽  
Vol 83 (3) ◽  
pp. 268-280 ◽  
Author(s):  
Jayani Chandrapala ◽  
Bogdan Zisu

Food engineering within the dairy sector is an ever developing field of study purely based on the application of engineering principles and concepts to any aspect of dairy product manufacturing and operations. The last 25 years of science and technology devoted to milk and milk products have led to major advances. The purpose of this paper is to review the history and current status of some engineered milk products and to speculate regarding future trends. Much of the advancement has been directed towards production capacity, mechanisation, automation, hygiene within the processing plant, safety, extensions in shelf life, and new product introductions that bring variety and convenience for the consumer. Significant advancements in product quality have been made, many of these arising from improved knowledge of the functional properties of ingredients and their impact on structure and texture. In addition, further improvements focused on energy efficiency and environmental sustainability have been made and will be needed in the future.


2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Dragan Milićević ◽  
Greta Krešić ◽  
Danijela Vranić ◽  
Tina Lešić ◽  
Jelana Nedeljković-Trailović ◽  
...  

The aim of this study was to determine the nutritional properties of raw milk, cheese and a traditional creamy dairy product called kajmak originating from the Zlatibor region in Serbia. Chemical composition, minerals, fatty acid (FA) profile, lipid quality indices, and the dietary intake of saturated fatty acids (SFA), cholesterol, salt and sodium were investigated in three sampling sessions during the period June–September 2019. All chemical properties of raw milk, cheese and kajmak differed significantly (P&lt;0.05), except lactose, salt and total proteins. Palmitic acid (C16:0) was present in the highest share, followed by oleic (C18:1cis-9) and myrstic (C14:0) acids, with no significant differences (P&gt;0.05) between products. Among the FAs, conjugated linoleic acids (CLA) were determined, and mean values of total FAs ranged from 0.16% in raw milk and kajmak to 0.31% in cheese. The recommended values for the lipid quality indices were not obtained for the analysed products. Despite a high sodium content, the tested dairy products can be considered valuable sources of calcium, chromium, zinc and selenium. In the future, additional efforts should be employed in product modification with the aim of optimising nutritional value and to obtain the protect designation of origin.


Author(s):  
I. Paska ◽  
Yu. Grinchuk ◽  
I. Artimonova

The article discusses the organizational and economic relations between the participants in the supply chain of milk and dairy products. Generally, organizational and economic relations are a set of relations between the participants of the dairy products chain, which are formed in the process of production, distribution and sale to consumers, as a result of which the economic interests of all its participants are realized. The peculiarities of dairy products of the chain are systematized and the basic principles, conditions for their balanced development are determined, contributes to the coordination of the economic interests of all its participants. It has been proved that economic interest is an important component of organizational and economic relations in the supply chain of milk and dairy products, and its main elements are: prices for raw materials and fnished products, costs of production, processing of raw materials, transportation, terms of mutual settlements, material interest of personnel, norms of fulfllment of contractual obligations, risks and the like. Review of the negative factors of organizational and economic relations in the dairy product chain and their impact on the effectiveness of each of its participants. As a tool to increase the production of raw milk, it is proposed to optimize the raw material zones of dairy processing enterprises, develop strategic programs for the development of the industry and stimulate consumer demand, as well as create industry clusters. The calculations for the distribution of costs and income between participants in the supply chain of milk and milk products prove the need to ensure the equivalence of exchange. In order to improve the efciency of the researcher, it was proposed to increase the volume of milk production and processing, as well as to establish mutually benefcial relations between its participants, connected by a single production cycle. The directions of innovation and investment development of the participants in the dairy products chain, especially the link of dairy cattle breeding, are highlighted. It is highlighted that the innovative renewal of the activities of the chain participants is a process of cyclical activities focused on the production of competitive dairy products of a new generation, which will contribute to an increase in turnover in order to obtain the highest proft of the chain participants and satisfy the demand of consumers with different income levels. Key words: dairy products chain, chain participants, exchange equivalence, organizational and economic relations.


1983 ◽  
Vol 46 (1) ◽  
pp. 41-46 ◽  
Author(s):  
J. C. BRUHN ◽  
A. A. FRANKE ◽  
R. B. BUSHNELL ◽  
H. WEISHEIT ◽  
G. H. HUTTON ◽  
...  

In recent years, milk and milk products have been implicated as a major contributor to dietary iodine. The possible sources of iodine in milk are supplemental iodine in dairy feeds, iodophor-containing sanitizers used at the dairy farm and/or the processing plant, iodophor-containing teat dips used to control the spread of mastitis among dairy cows, and iodine-containing medications used by veterinarians. A five-year program to determine the California raw milk iodine concentration and identify the sources of adventitious iodine has resulted in the California dairy industry deciding late in 1980 to reduce iodine supplementation of dairy feeds. This resulted in a decrease in milk iodine concentration in samples received in 1981 to 256 ± 234 μg/kg compared to 1980, when the concentration was 474 ± 304 μg/kg. The industry has set up a program to monitor the raw milk iodine concentration at the producer level, thus ensuring that the concentration will continue to decline.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Safwan Murshed

Aflatoxin M1 is one of the major fungal contaminants found in dairy products around the globe. The objective of this study was to investigate the incidence and occurrence of aflatoxin M1 (AFM1) in samples of milk and milk products in Yemen. The tested dairy product samples were collected from different sources for aflatoxin M1 (AFM1) in Yemen. A total of 250 local and imported samples consisting of 38 liquid milk, 60 powder milk, 62 yogurt, and 90 cheese samples which are marketed throughout Yemen were tested by using high-performance liquid chromatography (HPLC) along with a fluorescence detector and immunoaffinity column purification for detection of AFM1. High levels of AFM1 were detected in preserved milk (77.24%), ranging from 0.021 μg/L to 5.95 μg/L. On the other hand, AFM1 was detected in 66.66% and 68.42% in powdered milk and liquid milk samples, respectively. Among dairy products, 87.09% of yogurt and 81.39% of cheese samples were found contaminated with AFM1. The AMF1 values were higher than the acceptable range for humans set by the European Union. So, we concluded that dairy products used in Yemen showed an AFM1 content beyond the acceptable range, and this is a major factor for causing health-related complications including cancer. In the present study, we reported for the first time the presence of mycotoxins especially AFM1 in dairy products used in Yemen.


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