Our last Agar wars pitted 2 mould and yeast testing agars against eachother (see Malt Extract vs Rose Bengal). In this post, we take a look at 3 sparring partners, the total bacteria non selective testers. The contenders today are:

Nutrient agar
Tryptone Soya agar
Plate Count agar

At Dip-slides.com, these are the big 3 in bacteria testing. They all have their merits, but what are their downfalls? Let battle 2 commence.

Nutrient Agar

Nutrient agar is a general purpose growth medium that is great for use in a teaching environment. Nutrient agar grows a large number of non fastidious organisms and is therefore used in a great variety of applications such as:

• Metal cutting
• Fuel testing
• Cooling water
• Food and beverages
• Potable water
• Wastewater Paint
• Packaging
• Environmental Educational

Tryptone Soya Agar

TSA is a high nutrient growth medium and is another general purpose agar. It is very versatile as it tests for both aerobic and anaerobic, fastidious (but not very fastidious) and non fastidious bacteria.

It is often used for environmental testing in the pharmaceutical industry.

Other applications include:

• Water
• Environment
• Cosmetics
• Industrial
• Laboratory
• Food and Beverage

Plate Count Agar

Plate Count agar is mainly used in food science to test dairy products. However, it is used in other applications such as water testing (heterotrophic bacteria).

Plate count agar detects non fastidious organisms.

Other applications include:

• Food
• Environmental
• Cosmetics

So which agar is best?

All 3 of these agars are available with red spot dye when purchasing on our site, meaning that all 3 feature easy to see / count red spot colonies after incubation.

With all things considered, all 3 agars are versatile growth mediums suitable for total count testing. However, Tryptone soya is the most versatile since it tests for fastidious and non fastidious, aerobic and anaerobic bacteria. This makes it a particularly good all rounder.

Therefore, it's not a knockout but it's definitely a judge's decision in favour of Tryptone Soya Agar.

Take a bow TSA, you're an Agar Wars winner but only just.

References:

Oxoid