What are the advantages and the disadvantages of the plate count method?

Despite its shortcomings, the viable plate count is a popular method for determining cell number. The technique is sensitive and has the advantage of only counting living bacteria, which is often the important issue. Any concentration of microorganism can be easily counted, if the appropriate dilution is plated.

What are the limitations of heterotrophic plate count method?

The Limitations of HPC: The HPC method does not indicate the specific heterotrophic bacteria present or their sources. Instead, HPC testing indicates the culturable organisms present, which could be as low as 1% of the total bacteria present.

Why is the heterotrophic plate count preferred for food?

Why is the heterotrophic plate count preferred for food? The composition of food, cloudy when mixed with water, makes directing counting the microbes difficult and turbidity becomes unreliable. Why does ground beef have a better bacterial growth than a steak or roast?

What advantages does the pour plate method have over the streak plate method?

What advantage does the pour-plate method have over the streak plate method? The pour plate method requires less skill, has optimization built in, and will more likely produce the desired result.

Why spread plate method is recommended to use than pour plate method?

The bacterial colonies prepared by the pour plate technique is shown in figure 1. Bacterial growth of the spread plate only occurs on the surface of the plate. Therefore, spread plate technique gives well-separated colonies that are easy to count and pick up.

What is pour plate technique?

What is Pour Plate Method? The pour plate method is a microbiological laboratory technique for isolating and counting the viable microorganisms present in a liquid sample, which is added along with or before molten agar medium prior to its solidification.

What are the advantages of standard plate count?

The correct answer: An advantage of the standard plate count is that it e. Determines the number of viable cells.

What is a HPC test?

Measuring the heterotrophic plate count (HPC) is an analytic method that is a useful operational tool for monitoring general bacteriological water quality throughout the treatment process and in the distribution system.

How does heterotrophic plate count work?

The HPC (heterotrophic plate count) method is used to make an estimate of the number of aerobic and facultatively anaerobic heterotrophic bacteria in water. The concentration of heterotrophic bacteria in water gives information about the quality of the water and how much bacteria is removed during treatment.

Why is pour plate better than spread plate?

Generally, pour plates is the method for counting the number of colony-forming bacteria present in a liquid specimen. Pour plates also allow the identification of bacteria as aerobes, anaerobes or facultative aerobes. On the other hand, spread plates allow the isolation of specific clonal colonies.

What is the purpose of pour plate method?

The main purpose of the pour plate method is to isolate the pure culture from a mixture of different populations and demonstrate the cultural characteristics of the bacteria such as color, texture, size, elevation etc.

Which method is better spread plate or pour plate?

When comparing the accuracy of these two techniques, pour plate has a higher accuracy than the spread plate. Standard plate count method is a growth based approach that counts the number of living (growing/cultivable/viable) microorganisms within a sample.

What are the importance of heterotrophic bacteria?

Solution : (a) Heterotrophic bacteria a) They act as decomposers and help in the formation of humus. b) They help in the production of curd from milk. c) Many antibiotics are obtained from some species of bacteria. d) Many soil bacteria help in fixation of atmospheric nitrogen.

What is the function of heterotrophic bacteria?

Heterotrophic bacteria derive energy from organic compounds. They help in nutrient recycling. They decompose dead and decaying plants and animal remnants and help in biodegradation. Heterotrophic bacteria are used for making curd, antibiotics, nitrogen-fixation, etc.

Which method of determining bacterial number is the most accurate?

An easier and more accurate method to determine the microbial count is the plate method, where a food sample is placed on a culture medium plate. After an appropriate incubation period, you can count the number of colonies that have formed on the culture medium plate.

What is HPC method?

The Heterotrophic Plate Count tests (HPC) are flexible test methods for the presence and vitality of a diversity of microorganisms. As HPC analyzes measures and indicates pathogen removal and regrowth organisms, they are useful tools for evaluating drinking water samples.

What is the difference between pour plate and surface colonies?

Selection of Method a. Pour plate method: The pour plate method (9215B) is simple to perform and can accommodate sample or diluted-sample volumes ranging from 0.1 to 2.0 mL. It produces subsurface colonies that are relatively small, compact, and less apt to encroach on each other than surface colonies do.

What is the use of a pour plate method?

Pour plate Method: Principle, Procedure, Uses, and (Dis) Advantages. Pour plate method is usually the method of choice for counting the number of colony-forming bacteria present in a liquid specimen.

What is HPC plate count used for?

Applications The heterotrophic plate count (HPC), formerly known as the standard plate count, is a procedure for estimating the number of live, culturable heterotrophic bacteria in water and for measuring changes in swimming pools or during water treatment and distribution.

What are the disadvantages of pour plate method?

Disadvantages of Pour plate method. Preparation for pour plate method is time consuming compared with streak plate/and or spread plate technique. Loss of viability of heat-sensitive organisms coming into contact with hot agar. Embedded colonies are much smaller than those which happen to be on the surface.