What are spiral plates used for?

What are spiral plates used for?

Spiral platers are used extensively in food safety testing, as well as the pharmaceutical industry. The spiral plating method can save time and resources by cutting down on additional dilution and plating steps.

What is spiral plating method?

The Spiral® method enables the automatic and standardized plating of a sample – allowing 4 dilution series on one Petri dish. The sample is plated in a form of an increasingly dilute spiral (from the center to the periphery). The volume is calibrated and known at every point of the Petri dish.

What is the purpose of the spread plate technique?

The spread plate method is a technique to plate a liquid sample containing bacteria so that the bacteria are easy to count and isolate. A successful spread plate will have a countable number of isolated bacterial colonies evenly distributed on the plate.

What is pour plate technique?

Pour plate method is usually the method of choice for counting the number of colony-forming bacteria present in a liquid specimen. Because the sample is mixed with the molten agar medium, a larger volume can be used than with the spread plate. Each colony represents a “colony-forming unit” (CFU).

How does a spiral heat exchanger work?

In a spiral heat exchanger, each fluid flows through a single channel. If suspended solids settle on the heat transfer surface, the increased fluid velocity creates a scrubbing effect that removes the deposits. At the same time, the cold fluid enters at the periphery and spirals inward, exiting at the center.

How do you do a standard plate count?

The standard plate count method consists of diluting a sample with sterile saline or phosphate buffer diluent until the bacteria are dilute enough to count accurately. That is, the final plates in the series should have between 30 and 300 colonies.

How does a spiral plater work?

The spiral plater rotates the dish while simultaneously dispensing the liquid and either linearly moving the dish or the dispensing tip. If all movements are done in constant speed, the spiral created would have a lower concentration on the outside of the plate than on the inside.

How do you incubate agar plates?

Incubation:

1. Place each petri dish inside a zip lock bag to prevent drying out and to control odors.
2. Turn the plates upside down and put them in a warm place. The ideal temperature for incubation is 32° C or 90° F. Bacterial growth should start to become visible in about 2 -3 days.

Why is it important that the agar plates are incubated upside down?

Petri dishes need to be incubated upside-down to lessen contamination risks from airborne particles landing on them and to prevent the accumulation of water condensation that could disturb or compromise a culture.

What does CFU stand for?

colony forming unit
Simply speaking, CFU stands for “colony forming unit”, which describes the number of cells that can multiply to form a colony.

What is streaking method?

In microbiology, streaking is a technique used to isolate a pure strain from a single species of microorganism, often bacteria. Samples can then be taken from the resulting colonies and a microbiological culture can be grown on a new plate so that the organism can be identified, studied, or tested.

What is spiral plate heat exchanger?

The spiral plate heat exchanger is made by rolling two long metal plates around a center core to form two concentric spiral flow passages, one for each fluid. The plate edges are welded shut so that each fluid stays within its own passage and there is no flow bypassing or intermixing.

How is a spiral plater used to inoculate a plate?

Thanks to the spiral method, a known volume of sample is inoculated, from the center to the periphery of the plate. This pattern implies a decrease in the concentration of the sample while the process takes place. The Spiral Plater is a two-in-one method: diluter and plater at the same time.

How are spiral plates made in a petri dish?

What is spiral plating? Spiral plates are created using a spiral plater which is an apparatus that dispenses logarithmically decreasing volumes of sample onto the surface of a rotating petri dish forming a spiral pattern.

What kind of software do I need for spiral plates?

The spiral software comes as standard with the aCOLyte 3 HD and Protos 3 systems and is available as an additional module in the ProtoCOL 3. The software works with a number of spiral platers; WASP, Oxoid, Eddy Jet and Easy Spiral.

Why are spiral plates used in food testing?

Spiral platers are used extensively in food safety testing, as well as the pharmaceutical industry. The spiral plating method can save time and resources by cutting down on additional dilution and plating steps. Figure 1.