2 (Supplement), 2003 —COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY 21 Chapter III Factors that Influence Microbial Growth ability to participate in chemical/biochemical reactions, and its availability to facilitate growth of microorganisms. Introduction The factors discussed in this section constitute an inclusive, rather than exclusive, list of intrinsic, extrinsic, and other factors that may be considered when determining whether a food or Method of Obtaining Bacterial Growth Curve When more than one condition is somewhat adverse to microbial growth, their inhibitory effects are cumulative. The acidity of food is also an important factor affecting bacterial growth 1. Factors affecting microbial growth in food (a) Intrinsic factors: These are inherent in the food. Vinegar and lemon juice have a similar effect. Temperature. They include: Hydrogen ion concentration (pH), moisture content, nutrient content of the food, antimicrobial substances ad biological structures. Factors that Influence Microbial Growth December 31, 2001 Evaluation and Definition of Potentially Hazardous Foods 1. Methods and Results: The influence of temperature and pH was studied through fermentation and modelling. Aims: To study the effect of different fermentation conditions and to model the effect of temperature and pH on different biokinetic parameters of bacterial growth and exopolysaccharides (EPS) production of Streptococcus thermophilus ST 111 in milk‐based medium. Since bacteria are easy to grow in the lab, their growth has been studied extensively. 9. Temperature is the most efficient means to control microbial growth. Bacterial growth curve and its significance. For example, bacteriostatic treatments inhibit the growth of bacteria, whereas fungistatic treatments inhibit the growth of fungi. More acidic foods can typically be stored longer without spoiling. Microbial growth on meat products, as well as other foods, is affected, not only by the type and level of initial contamination but also by various factors associated with the product (intrinsic) or its environment (extrinsic). When a broth culture is inoculated with a small bacterial inoculum, the population size of the bacteria increases showing a classical pattern. Bacteria have a minimum, optimum, and maximum temperature for growth and can be divided into 3 groups based on their optimum growth temperature: psychrophils, mesophils, thermophils, or … 17.2: Factors that Influence Bacterial Growth - Biology LibreTexts Vol. Microbial growth •The microbial growth is the increase in number of cells rather than in size of individual cells. Factors affecting Microbial growth Physical factors •pH •Temperature •Osmotic pressure •Hydrostatic pressure As our foods are of plant and animal origin, it is worthwhile to consider those characteristics of plant and animal tissues that affect the growth of microorganisms. Growth Curve. Inhibition of Microbial Growth. Factors affecting microbial growth in food (a)Intrinsic factors: These are inherent in the food. Although each factor affecting growth is considered separately in the following discussion, these factors occur simultaneously in nature. Sofos, in Encyclopedia of Food Safety, 2014. When plotted on a graph, a distinct curve is obtained referred to as the bacterial growth curve. Factors that determine whether a particular treatment is -cidal or -static include the types of microorganisms targeted, the concentration of the chemical used, and the nature of the treatment applied. 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