Since bacteria are easy to grow in the lab, their growth has been studied extensively. 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. Microbial growth •The microbial growth is the increase in number of cells rather than in size of individual cells. Vol. Preserving agents that increase the acidity of food, such as citric acid, are commonly added to help prevent bacterial growth and allow for longer storage. Growth Curve. For example, bacteriostatic treatments inhibit the growth of bacteria, whereas fungistatic treatments inhibit the growth of fungi. 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 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… Vinegar and lemon juice have a similar effect. When plotted on a graph, a distinct curve is obtained referred to as the bacterial growth curve. 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. 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. Factors affecting microbial growth in food (a)Intrinsic factors: These are inherent in the food. Bacterial growth curve and its significance. Temperature is the most efficient means to control microbial growth. •The requirements for microbial growth can be divided into two main categories: physical and nutritional. Factors affecting Microbial growth Physical factors •pH •Temperature •Osmotic pressure •Hydrostatic pressure More acidic foods can typically be stored longer without spoiling. The acidity of food is also an important factor affecting bacterial growth 1. Although each factor affecting growth is considered separately in the following discussion, these factors occur simultaneously in nature. 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 Factors affecting microbial growth in food (a) Intrinsic factors: These are inherent in the food. 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. 1. 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. 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). Methods and Results: The influence of temperature and pH was studied through fermentation and modelling. Sofos, in Encyclopedia of Food Safety, 2014. J.N. Temperature. When a broth culture is inoculated with a small bacterial inoculum, the population size of the bacteria increases showing a classical pattern. When more than one condition is somewhat adverse to microbial growth, their inhibitory effects are cumulative. Inhibition of Microbial Growth. 9. Method of Obtaining Bacterial Growth Curve Growth curve efficient factors affecting microbial growth in food biology discussion to control microbial growth, their growth has been studied extensively: influence., their growth has been studied extensively antimicrobial substances ad biological structures and! 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