Food. Factors Affecting The Growth Of Microbes. Factors affecting microbial growth FACTORS AFFECTING GROWTH … Looks like you’ve clipped this slide to already. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Factors affecting Microbial growth Physical factors •pH •Temperature •Osmotic pressure •Hydrostatic pressure •Moisture •Radiation •Oxygen concentration Nutritional factors … Radiation. Different organisms react to their environment in different ways. Osmotic pressure (salt tolerance). Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Factors Affecting. Most microorganisms, including most human pathogens, are neutriphils, organisms that prefer a neutral pH level. Factors Affecting Bacterial Growth Temperature Atmosphere – O2 & CO2 H-ion concentration Moisture & drying Osmotic effects Radiation Mechanical & sonic stress. There are about 25 genera of bacteria in food causing either spoilage and or user in desirable effects. Factors affecting the growth of microorganisms. 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). I-Semester. Clipping is a handy way to collect important slides you want to go back to later. Physical factors- Temperature, pH, osmotic pressure, hydrostatic pressure and radiation. Factor acting deadly on Factors on Growth • Most organisms grow in fairly moderate environmental conditions • Extremophiles –grow under harsh conditions that would kill most other organisms . Food associated microorganisms are affected by 2 types of factors: Intrinsic factors :Includes physicochemical properties of food such as, Nutrients. Table 3-2 lists the approximate minimum a w values for the growth of selected microorganisms relevant to food. FACTORS AFFECTING PLANT GROWTH Plant growth factors control or influence plant characteristics as well as adaptation. The growth of microorganisms is influenced by various physical and chemical factors of their environment. The factors are: 1. If you continue browsing the site, you agree to the use of cookies on this website. INTRINSIC FACTORS : OXIDATION- REDUCTION POTENTIAL OR REDOX POTENTIAL The growth of microorganisms in food differs if the growth medium will act as electron donor or electron receptor. Oxygen requirement. Nutrients needed by microorganisms include: Carbon carbon containing compounds are needed as an energy source (ex. Looks like you’ve clipped this slide to already. Scholar, Division of Soil Science and Agricultural chemistry, ICAR-IARI, New Delhi-110012 Introduction: Soil microorganisms (Flora & Fauna), just like higher plants depends entirely on soil for their nutrition, growth and activity. Antimicrobial constituents •The requirements for microbial growth can be divided into two main categories: physical and nutritional. As the following section shows, growth may be profoundly affected by a number of physical factors. The genetic factor is also called internal factor because the basis of plant expression Factors Affecting Microbial Growth Control of Microbial Growth: Introduction Early Now customize the name of a clipboard to store your clips. 5 (factors affecting microbial growth), Lecture 3 intrinsic and extrinsic factors, No public clipboards found for this slide. The factors are: 1. … The process of growth depends on the availability of requisite nutrients and their transport into the cells, and the environmental factors such as aeration, O 2 supply, temperature and pH. Factors that Influence Microbial Growth ability to participate in chemical/biochemical reactions, and its availability to facilitate growth of microorganisms. pH measures how acidic or basic (alkaline) a solution is, and microbes may grow in either acidic, basic, or neutral pH conditions. Factor of relative humidity. Bacteria by virtue of mechanical strength of their cell wall are able to withstand a wide range of external osmotic variations. Temperature 3. pH 4. Soil Microorganisms: key factors affect distribution, activity and population Authors: Rajendra Kumar Yadav and Malu Ram Yadav, Mahendra Kumar Yadav PhD. Microbial Growth FATTOM Food Acid Temperature Time Oxygen Moisture Factors Affecting Microbial Growth. Microorganisms show varying sensitivity to different types of factors. APIdays Paris 2019 - Innovation @ scale, APIs as Digital Factories' New Machi... Mammalian Brain Chemistry Explains Everything, No public clipboards found for this slide. Some like high pH levels, but most often, if conditions are too acidic, then the organism's enzymes break down. Somewhere between these maximum and minimum points lies the optimum temperature at which the bacteria grow best. Bacteria grow only in the presence of oxygen, called: strict aerobes. Learn vocabulary, terms, and more with flashcards, games, and other study tools. At the temperature of -1 – 3oC, Dr. Shyamal Kr Paul 21. The factors can be generally classified as intrinsic and extrinsic factors. At certain temperature the growth rate become maximum, this temperature is known as optimal temperature. Intrinsic Factors • Nutrients • pH and buffering capacity • Redox potential • Water activity • Antimicrobial constituents • Antimicrobial structures . The following points highlight the six main physical factors affecting the growth of microorganisms. Summarize the adaptations of extremophiles to their natural habitats 3. Procedure (Incubators only): Different labs will have vastly different equipment and bacterial strains, so this lab exercise is designed openly for change with two procedures, one for those using only incubators and another for those using both incubators and water baths. Growth Factors • Some microbes have the enzymes and biochemical pathways needed to synthesize all cellular components using minerals and sources of energy, carbon, nitrogen, phosphorus and sulfur. Gaseous Requirements 3. See our Privacy Policy and User Agreement for details. Factor Of Relative Humidity. FACTORS AFFECTING GROWTH FACTORS AFFECTING BACTERIAL GROWTH TEMPERATURE NUTRIENT AVAILABILITY WATER SUPPLY OXYGEN SUPPLY ACIDITY OF THE MEDIUM 31. When microorganisms grow in food, they cause varying degrees of change in the food's characteristics as a result of metabolic activity. Factors Affecting. Temperature requirement. In general, there are two factors affecting plant growth and development : genetic and environmental. Temperature range – growth does not occur above the maximum or below the minimum. If you continue browsing the site, you agree to the use of cookies on this website. Do you have PowerPoint slides to share? The most important factors that affect microbial growth in foods can be summarized in the following categories: (i) factors related to the food itself, the “intrinsic factors,” which include nutrient content, water activity, pH value, redox potential, and the presence of antimicrobial substances and mechanical barriers to microbial invasion; (ii) factors related to the environment in which the food is stored, the … Growth An orderly increase in the quantity of all the cellular constituents. Several factors encourage, prevent, or limit the growth of microorganisms in foods, the most important are a. w, pH, and temperature. Purpose: to observe the affect that different temperatures have on the growth of microorganisms. Use the terms that describe a microbe’s growth range or requirement for each of the factors that influence microbial growth 2. Accessory – when they enhance growth, without being absolutely necessary for … MICROORGANISMS Factors Affecting Microbial Growth Food. Pressure 6. 7.3 Influences of environmental factors on growth 1. On further increasing the temperature above optimal, growth rate decreases abruptly and completely ceases with reaching maximum temperature. Solutes and Water Acidity 2. for growth depending on other growth factors in their environments. In cases of bacteria ,growth refers to the rapid increase in the number of bacteria. 3. The key to a productive staff is creating and maintaining a safe and healthy work environment. See our Privacy Policy and User Agreement for details. Solutes and Water Acidity: Water is one of the most essential requirements for life. View Lecture Slides - 6-16 Factors_Affecting_Microbial_growth.ppt from BIO 150 at Wichita State University. Most spoilage bacteria grow best near neutral pH Pathogenic bacteria even more narrow in tolerance range of near neutral Yeast and moulds have much greater tolerance to acidic (lower) pH ; 4 Start studying FDST 421 Quiz #10 [Factors affecting growth & survival of microorganisms in foods]. 2. Biotechnology Prachi Gupta glucose) for building blocks. Higher storage temperature will lead to lower humidity. Factors affecting microbial growth in foods: Factor affecting growth of microorganisms in food are divided into two types: Intrinsic parameter or factors; Extrinsic parameter or factors; 1. Growth of microorganisms in food is dependent on various parameters. Presentation Summary : Factors affecting the growth of microbes. Water activity / moisture content . 2. 3. pH: pH affects the ionic properties of bacterial cell so it affects the growth of bacteria. Nitrogen needed for amino acids and nucleotides; some can synthesize … If you continue browsing the site, you agree to the use of cookies on this website. Factors Affecting Microbial Growth Food. Hence factors such as osmotic pressure and salt concentration of the solution affect the growth of bacteria. Factors affecting microbial growth in foods. The growth of microorganisms is a highly complex and coordinated process, ultimately expressed by increase in cell number or cell mass. Factors affecting microbial growth in food • Intrinsic Factors • Environmental Factors • Implicit Factors • Processing Factors . In Situ Bioremediation;Types, Advantages and limitations, Customer Code: Creating a Company Customers Love, Be A Great Product Leader (Amplify, Oct 2019), Trillion Dollar Coach Book (Bill Campbell). Chemical factors- Oxygen, carbon, nitrogen, phosphorus, sulfur, etc. For example, Gram (-) bacteria are generally more sensitive to low a w than Gram (+) bacteria. Factors that Influence Microbial Growth December 31, 2001 Evaluation and Definition of Potentially Hazardous Foods 1. Redox potential. You can change your ad preferences anytime. One indicator of microbial response is their taxonomic classification. Presented By : Now customize the name of a clipboard to store your clips. Temperatures below the minimum stop bacterial growth … Factors affecting bacterial growth Factors affecting bacterial growth are: 1. PHYSICAL FACTORS Temperature. If you continue browsing the site, you agree to the use of cookies on this website. The PowerPoint PPT presentation: "Factors affecting microbial growth" is the property of its rightful owner. pH and buffering capacity . In the soil solution gases (oxygen, methane and carbon dioxide), and microorganisms are dissolved. View BIOL_2265-_Factors_affecting_microbial_growth.ppt from BIOL 2265 at University of the West Indies at St. Augustine. Factors Affecting the Growth of Microorganisms in Foods . Food. The factors influencing the growth of microorganisms are physical, chemical and biological in nature. Guided by: 1) Oxygen requirement: Bacteria are divided into four groups according to oxygen requirement: 1. Nitrogen needed for amino acids and nucleotides; some can synthesize … Microorganisms also prefer a certain pH level in the substance or environment in which they grow--that is, they prefer to have particular acidic qualities in their surroundings. Factors affecting microbes in foods. glucose) for building blocks. Some of these changes, like those taking place during fermentation, are desirable, while others, like those resulting in food spoilage and food poisoning, are undesirable. Temperature Theoretically, bacteria can grow at all temperatures between the freezing point of water and the temperature at which protein or protoplasm coagulates.