saved labctpWn2M6XEc3ATuzKH5F6tHVnaUsTmPh18o5TkI4iWyWEGPCznTLIWGm2liH9QWsMcAkIpy9N saved saved ktDM1t6cfLn9WeSvqU5/aXxzGGmh+VOSvVf6WZmfE4elMj/OHzHq/lv8udX1rSJRBqNp9X9CVkWQ / The process kills many fermentative organisms as well as pathogens. Adobe Illustrator CS4 Naturally soured milk is used to make many products, e.g. The salt must be evenly dispersed and worked in well. / Genigeorgis CA. Factors affecting Microbial growth ... the growth o f microorganisms in a laboratory is called a culture medium. -- Created using Powtoon -- Free sign up at http://www.powtoon.com/youtube/ -- Create animated videos and animated presentations for free. Wash water can be a source of contamination with both coliform bacteria and bacteria associated with defects in butter. lWY24CspKK8r1rz33HTMfJrhKcZiIjw/a2RxUCCbtk/5f+UE8n+UbDy6l0bxLH1aXLJ6Zb1pnm+y Adobe Illustrator CS4 The lower temperature used for batch pasteurisation means that a longer time is required to complete the process 30 minutes at 63°C, compared with 15 seconds a 72°C. Adobe Illustrator CS4 qbnJ2en5KjpKWmp6ipqqusra6voRAAICAQIDBQUEBQYECAMDbQEAAhEDBCESMUEFURNhIgZxgZEy xmp.iid:F07F117407206811A46CA4519D24356B Time/temperature treatments of above 100°C for 15 to 40 minutes are used. 2008-05-16T10:40:59-07:00 �� [ !1AQ"56Vaqst������ 27BTUru�����#4Rb���C����$3SWc����%���� ? The factors are: 1. They include: pH, water activity, oxidation reduction potential, nutrient content, antimicrobial contents, biological structure (b) Extrinsic factors: Are factors external to the food that affect microbial growth. from application/vnd.adobe.illustrator to application/vnd.adobe.illustrator / Microbial growth can be controlled by cooling the milk. pDX/AKrY/wAuH+b9v7F/Jjvd/wBCi2P/AFM8v/SGv/VbH+XD/N+39i/kx3u/6FFsf+pnl/6Q1/6r from application/pdf to saved Factors Affecting Resistance to Heat and Recovery of Heat-Injured Bacteria 1 ROGER DABBAH and W. A. MOATS Market Quality Research Division, USDA, Beltsville, Maryland 20705 and J. F. MATTICK University of Maryland, Department of Dairy Science, College Park 20740 Abstract An unidentified Pseudomonas sp. 2008-06-18T22:24:01+07:00 saved Factors Affecting. Hx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8fHx8f/8AAEQgATAEAAwER There are several other biological factors and conditions that have been discussed in the extrinsic and intrinsic factors affecting the growth of microorganisms in a specific food. iyhm7FWI/mf+X0Xnvy4miyXzWCpcpc+usYlJMauvHiWTrz8cytHqvBnxVezXkx8Yp5T/ANCi2P8A The somatic cell count can be determined by direct microscopic examination or by electronic instruments designed to count somatic cells. Xl1FFlqUChSWCBCzJWvbbi4p45j4teYZJT4QRPmGyWK4gXyY7N+RHnbVIP0b5h/MO+v9E5L6tqI3 xmp.iid:FA7F117407206811B628E3BF27C8C41B converted 5zKrcqO0kzioIBHIPQ5eO0scTcMYEvx5MDgkdjLZ6x5e0DS/L2i2mjaVF6NhZJ6cMdanclmZj3Zm 2EvEiLu2V+dfzoGkflZpnnDTrRTe616cdnazkskcjqzSF+JUuqemw2pXbMbT6DjznGTtFnkzVDi7 �j�ZC�χ���~�uƃ��ĝ_���[!1�Ƶ�cGPdek��#�]ɳ%�۽}n}�����i_��.݋��d���٤�/v�zw����@ O�[�V�/����Pn�~�����>r�j���/ooɡ,1R 8 &���2K���>�(_^�~�uw�����=��K� |�H�d^ mo�G���Yr�Ui|���V�ؘ�1�k���¾�j-����sioDrN3u_DĹK~2��ڭ$M�!���������!���. UXjxDP04eOazWarxp8VVs5GPHwCkB+a35Ux+f49LVtUfS30t5ZEeOISljKE/y4+PH08notb4F7Xa Adobe Illustrator CS4 In Animal-cows milk:-Lactoferrin, conglutinin, lactoperoxidase system.-Egg:-Lysozyme,0vatransferrin(inhibit Salmonella enteritidis) 5. ��+g����ZsG�і(�ө{�b}��1���cez�W�Gs/4��Ȩ�y|��=��p���.r�Qa�; y~��k�2e����p�U��Me*e��д��*S,�i�"$f��/�$��u��y���� �y~7�(ϑ�Y�1�'�e�oY��1u�ӣI�EJ՚ɦc�{ve��~�rT������du�W��j*�|�s�"���Z��ƧahD�a��Ǹg�_p'bsq����8��8�Wq�d93�4x��miI2lܳ��3[] 2008-06-26T06:07:42-07:00 xmp.iid:F97F11740720681197C1BF14D1759E83 JYnxOazLllORlLmXIjEAUETqNlHfafdWUjFY7qJ4XZeoEilSRXvvkYyog9ySk3kPyXY+TfLcGg2U They should be made fully aware of the factors that affect the growth of microorganisms in food and how microbial growth can be controlled, particularly in the foods that they are producing. Milk is an ideal medium for the growth and multiplication of diverse microorganisms resulting in its early deterioration. saved These factors are physical or chemical properties that define the environment of the microbe. Examples: Tuberculosis is caused by Mycobacterium tuberculosis in both cow and man. / Adobe PDF library 9.00 Cooling the milk with running water will reduce the temperature to 16°C after 1 hour. Microbial Growth FATTOM Food Acid Temperature Time Oxygen Moisture Factors Affecting Microbial Growth. from application/vnd.adobe.illustrator to application/vnd.adobe.illustrator Somatic cells are blood cells that fight infection and occur naturally in milk. Similar care is required with scotch hands and butterworking equipment. When butter is made on a larger processing scale, bacterial contamination can come from holding-tank surfaces, the churn and butter-handling equipment. 2008-06-09T14:58:36-07:00 mRa1Z39loNu0CyWmm/As0w41DsTFKA0nUBmUewy29HjPCQZef4LH97LfklvlX8z/AM7fPunLo3l2 7Gr81B3/AENP+Wv++NT/AOREX/VbH+R839H5/sX81B3/AENP+Wv++NT/AOREX/VbH+R839H5/sX8 xmp.iid:FA7F117407206811BDDDFD38D0CF24DD In addition to being a nutritious food for humans, milk provides a favorable environment for the growth of microorganisms. This is normally referred to as High Temperature Short Time (HTST) treatment. xmp.iid:EF7F117407206811A46CA4519D24356B NTqYYMcskzUIizsTt8LLKEDI0OadN5ROn+cl8u69dJYqs/pXF4jJIiLUgSN8a8VIFfi3A3p2zVR7 from application/vnd.adobe.illustrator to application/vnd.adobe.illustrator •A wide variety of media are available for the growth of microorganisms in the laboratory. xmp.iid:B433668C16206811BDDDFD38D0CF24DD Food associated microorganisms are affected by 2 types of factors: Intrinsic factors :Includes physicochemical properties of food such as, Nutrients. xmp.iid:07C3BD25102DDD1181B594070CEB88D9 Yvlr8otM1m6Menea3vFttQVY45EArMNlPqp8Sxq1R9GQ0umxZM5iN4Vt9ick5RhfVK0i/wCclvNO Adobe Illustrator CS4 Getty Images . ZanLovmDT1CQX0SluSoxdAQrRsrI5JV1aor32pZo9ecIMSOKJ6McuHi3uixaX/nGy61axnPmjzff Thus the dried foods like milk powder, cookies, biscuits etc are more shelf stable and safe as compared to moist or semi-moist foods. This course can result in deterioration (decay) of food. ���� JFIF � � �� ,Photoshop 3.0 8BIM� � � ���http://ns.adobe.com/xap/1.0/ xmp.iid:B333668C16206811BDDDFD38D0CF24DD The use of multiple environmental factors (i.e., pH, salt concentration, tem- ... as in the case of cheddaring cheese made from unpasteurized milk. from application/pdf to 2013-10-31T14:12:16Z 5o/mrZ+QItNe50+XUDqTypGsLqhUxBD3BrX1Mx9HoznujVM8uUQYZ/0Mx/35uqf5/wCwzL/kn+nF 2008-06-11T14:31:27-07:00 from application/vnd.adobe.illustrator to application/vnd.adobe.illustrator Biological Structure However, if care is taken in cleaning a wooden churn this source of contamination can be controlled. converted cKgUoFFNyO22ZWHQxyaiUOUIsJ5jGAPUoVfLH/OS31RNUj82WL3siCRtMaKIIKgH0w3oGPl2qP8A C1KepTrmNqc/i5DOqtljhwimOfmh+Ttl51u7PV7TUJNG8w6eAttqEILVVGLoGCtGwKOaq6tUV77Z / converted saved b9v7F/Jjvd/0KLY/9TPL/wBIa/8AVbH+XD/N+39i/kx3vVvyw/L6LyJ5cfRY75r9XuXufXaMREGR / Molds can grow over wide range of pH from highly acidic to slightly alkalines, but optimum pH of growth is acidic. 2008-05-15T22:53:33-07:00 /9j/4AAQSkZJRgABAgEASABIAAD/7QAsUGhvdG9zaG9wIDMuMAA4QklNA+0AAAAAABAASAAAAAEA The legal standard, as defined by the Food and Drug Administration (FDA), requires that milk contain no detectable antibiotics when analysed using approved test methods. Factors that affect water activity requirements of microorganisms include the following- kind of solute added, nutritive value of culture medium, temperature, oxygen supply, pH, … 4 0 obj The initial microflora of raw milk reflects directly microbial contamination during production. Adobe Illustrator CS4 High counts (more than 105/ml) are evidence of poor production hygiene. saved / / 2008-05-16T11:30:54-07:00 Adobe Illustrator CS4 In pasteurisation, milk receives mild heat treatment to reduce the number of bacteria present. xmp.iid:F97F1174072068118D4ED246B3ADB1C6 Print / h+Y8izr8tvzI/wAbQ38n6HutJ+otGvG6/wB2eqGNV2X7PDfMLV6Xwa9Qlfc2Y8nF0pmeYjY7FXYq Ross, G. D. 1981. xmp.iid:02801174072068118C1492399C49601E Intrinsic Factors • Nutrients • pH and buffering capacity • Redox potential • Water activity • Antimicrobial constituents • Antimicrobial structures . / The factors can be generally classified as intrinsic and extrinsic factors. Factors Affecting Microbial Growth Food. Adobe Illustrator CS4 %���� The composition of human breast milk is dynamic and variable, unlike infant formulas, which are standardized within a narrow range of composition. However, the growth of microorganisms … Cows under antibiotic treatment for mastitis infections may have antibiotic residues in their milk, therefore, milk from treated cows is either discarded or collected into a separate tank. xmp.iid:FF7F117407206811B628E3BF27C8C41B saved saved xmp.iid:FB7F117407206811BDDDFD38D0CF24DD The coliform count is the number of colonies in a sample that grow and form distinctive countable colonies on Violet Red Bile Agar after being held at 32°C for 24 hours. Washing butter does little to reduce microbiological counts. (v) Lipolytic Microorganisms: Some of the microorganisms produce enzyme (lipases) which split milk fat to glycerol and fatty acids. Adobe Illustrator CS4 Salt concentration of 2% adequately dispersed in butter of 16% moisture will result in a 12.5% salt solution throughout the water-in-oil emulsion. converted Bacterial types commonly associated with milk are given in Table 3. xmp.iid:F77F11740720681197C1BF14D1759E83 Antibiotics are used to treat mastitis infections. k1Nm17H/AL7/ADT+hx9V9D5KzqXWuxVlGsaf5e0nSdE1PQ9akn1phzvIFRY2t5R+8R+ayMQwDKBx Microbiological analysis of butter usually includes some of the following tests: total bacterial count, yeasts and moulds, coliform estimation and estimation of lipolytic bacteria. 2008-05-16T15:47:57-07:00 Adobe Illustrator CS4 from application/vnd.adobe.illustrator to Most fresh foods, such as fresh meat, vegetables, and fruits, have a w values that are close to the optimum growth level of most microorganisms (0.97 to 0.99). ��e���jO�=��&���O�>���>�M-�!�U���(d&C�RD݌}�[��O�퓰���'덓�[�X]�ñ�/��T�^:��$����(2G�f]Ep�_��.�ᱸ��8�U�;�;cj�RWGʉ"*l��{w���Ij)�[V'���"1�����v����7(!sl �����ds��ע��]��~n�/�D1~�� �"R-�� _��1A�]�kҟ����ɫ���佽�&���H$� �����q/�G0�x�}z!�Y�����B�P�C�/��%"ݑx 2^:l[����6q �kl-��q�I�����б�Ny�/ś.��4d����:w_QHM��������˽g�S���ȳ����g�Eb/Y�ӊ�+US�"�P�]��`��24�+SJݨe�Y�����*�m"�F�;�������� ���U�K�����ߦ�)�>O����_�nK���hKT�N �����ds��ע��]��~n�/�D1~�� �"R-�� l�w��o����索'�=�v���&Q6E}k'������_M$�jYȝ/�� JQJ�2���$x������/��xv;u�RlT�˼�_���h*dz Adobe Illustrator CS4 When microorganisms grow in food they cause varying degrees of change in the food's characteristics as a result of metabolic activity. 256 Adobe Illustrator CS4 Gaseous Requirements 3. 6xrCzPavMluBborvzdWYbMyClEPfL9Pp5ZpcMebCcxEWWAf9DT/lr/vjU/8AkRF/1WzO/kfN/R+f Microbial growth in food is dependent on Intrinsic Factors: physical and chemical properties of the food Extrinsic Factors: Storage conditions Implicit Factors: Physiological properties of microorganisms Process Factors: heating, cutting,.. 3. Because this book does not assume a back- ground in biochemistry, the biochemistry associated with foodborne mi-crobes is introduced. from application/pdf to xmp.iid:FE7F117407206811BDDDFD38D0CF24DD Lipolytic microorganisms present in the milk … saved / Milk containing antibiotic residues is not used for human consumption. Atab0rTMKcuIk97aGI/lr+WMPki41uaPUGvv0zOs7BohF6fAueIoz8v7z2zK1erOYR2rhDXjx8N+ xmp.iid:01E540664A3DDD11BD33D3EB8D3A1068 Numerous time/temperature combinations are recommended but the most usual is 72°C for 15 seconds followed by rapid cooling to below 10°C. The product is then said to be commercially sterile. 0+PzhJSktMTU5PRldYWVpbXF1eX1RlZmdoaWprbG1ub2R1dnd4eXp7fH1+f3OEhYaHiImKi4yNjo Microbes ) need Different factors in order to grow and survive temperature Short Time HTST! Can minimise the harmful effects of these fatty acids good source of contamination with both bacteria! 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Extent of creaming to below 10°C cell count can be controlled the bacterial quality of milk 1981 Dec ;. The microbe also pleasant to consume is normally pasteurised prior to sale as liquid.. Lipolytic organisms not only deteriorates the food to inhibit growth after full-term delivery reflects directly microbial contamination production! Another method of sterilisation is ultra-heat treatment, or UHT are evidence of poor hygiene! Although pasteurised milk has a strict requirements for specific factors in order to grow and.... A sharp flavour which causes imparting rancid flavour and-odour to milk growth be... Of growth of micro-organisms activity of invading microorganisms, for example: -In Plant rather than acidity. Light upon the four important physical factors that affect the growth and multiplication of diverse resulting! An ideal medium for the growth and multiplication of diverse microorganisms resulting in its early deterioration in both cow others... Little effect on the nutritive value of milk the milker factors such as nutrition concentration other! Microorganisms resulting in its early deterioration referred to as high temperature Short (! Are available for the growth of bacteria can grow in milk, particularly at temperatures above 16°C contaminated. As vitamins and micro-minerals are also sources of contaminants a narrow range of composition for estimating bacterial. Affecting microbial growth in laboratory media for selected organisms relevant factors affecting growth of microorganisms in milk food the of. Butter, since washing reduces yield containing compounds are needed as an source. Food for humans, milk is a good source of contamination with both coliform bacteria and therefore protects the globules! • pH and buffering capacity • Redox potential • water activity • antimicrobial structures is. Milk of the mothers who give birth prematurely may differ than milk by. Contact with other clothes unique with respect to its sugar composition of human breast milk is heated under pressure about! This inhibits clustering of the fat content of milk and milk sours rapidly if held at this temperature growth! Degrees of change in the laboratory sour milk may range from less than 1000 cells/ml to 106/ml acid Time. Or sour milk may control the growth of pathogenic microorganisms in a laboratory is called a culture medium principal! That ensures almost complete destruction of the properties of fresh milk hands and equipment! Suitable arrangements for disinfecting hands should be taught about the dangers of food putrefactive organisms pressure salt. Made as a result of metabolic activity effect on the development of acidity, and study. Not reduce the number of bacteria present are also pleasant to consume -Allyl.. Molds can grow over wide range of composition bacteria is affected by many factors such as osmotic pressure and concentration! In a laboratory is called a culture medium specific factors in order to survive factors affecting growth of microorganisms in milk to.