Pascal

Definition

Pascal is a unit of pressure measurement in the International System of Units (SI). It is defined as the force of one newton exerted over an area of one square meter, and is commonly used to quantify the pressure exerted by physical methods used to control microorganisms.

5 Must Know Facts For Your Next Test

1. High pressure is an effective physical method for controlling microorganisms, as it can disrupt cell membranes and denature proteins, leading to cell death.
2. Autoclaving, a common sterilization technique, uses high-pressure steam at temperatures above 121°C to kill microorganisms.
3. Hydrostatic pressure is used in the food industry to inactivate vegetative cells and some spores, while preserving the quality and nutritional value of the food.
4. Pressure can also be used to enhance the efficacy of other antimicrobial treatments, such as the combination of high pressure and heat, known as high-pressure thermal processing.
5. The pascal is a small unit of pressure, with 1 pascal equivalent to a force of 1 newton exerted over an area of 1 square meter. Higher pressures are often measured in kilopascals (kPa) or megapascals (MPa).

Review Questions

• Explain how high pressure can be used as a physical method to control microorganisms.
  • High pressure can be an effective physical method for controlling microorganisms because it can disrupt cell membranes and denature proteins, leading to cell death. This is the principle behind the use of autoclaving, a common sterilization technique that uses high-pressure steam at temperatures above 121°C to kill microorganisms. Additionally, hydrostatic pressure is used in the food industry to inactivate vegetative cells and some spores, while preserving the quality and nutritional value of the food. The pascal is the unit of pressure measurement in the International System of Units (SI), and higher pressures are often measured in kilopascals (kPa) or megapascals (MPa).
• Describe how the combination of high pressure and heat, known as high-pressure thermal processing, can enhance the efficacy of antimicrobial treatments.
  • The combination of high pressure and heat, known as high-pressure thermal processing, can enhance the efficacy of antimicrobial treatments. High pressure can disrupt cell membranes and denature proteins, making microorganisms more susceptible to the effects of heat. This synergistic effect can lead to more effective inactivation of microorganisms compared to using either high pressure or heat alone. The pascal is the unit of pressure measurement in the International System of Units (SI), and higher pressures are often measured in kilopascals (kPa) or megapascals (MPa). The use of high-pressure thermal processing can be particularly useful in the food industry, where it can help to inactivate vegetative cells and some spores while preserving the quality and nutritional value of the food.
• Analyze the role of atmospheric pressure and hydrostatic pressure in the context of using physical methods to control microorganisms.
  • Atmospheric pressure and hydrostatic pressure play important roles in the context of using physical methods to control microorganisms. Atmospheric pressure, which at sea level is approximately 101.325 kilopascals (kPa), can influence the effectiveness of physical methods like autoclaving, which relies on high-pressure steam to kill microorganisms. Hydrostatic pressure, which is the pressure exerted by a fluid due to the force of gravity, can also be used to inactivate vegetative cells and some spores, as seen in the food industry's use of high-pressure processing. The pascal, the unit of pressure measurement in the International System of Units (SI), is used to quantify the pressure exerted by these physical methods, with higher pressures often measured in kilopascals (kPa) or megapascals (MPa). Understanding the role of pressure in controlling microorganisms is crucial for the effective application of physical methods in various industries, such as healthcare and food production.

Related terms

Pressure: The force exerted per unit area, measured in units such as pascals or pounds per square inch (psi).

Atmospheric Pressure: The pressure exerted by the weight of the Earth's atmosphere, which at sea level is approximately 101.325 kilopascals (kPa).

Hydrostatic Pressure: The pressure exerted by a fluid, such as water or blood, due to the force of gravity acting on the fluid.