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Loading the dishwasher can be a sore subject. Everyone claims to have perfected their own foolproof 'technique', yet no two methods are the same.

But now scientific research claims to have discovered the definitive way to organise a dishwasher's racks.

And the study, which has provided the most detailed analysis of how water circulates inside a household dishwasher, even suggests that most people pack their appliance the wrong way. 

The findings has helped provide clues to the best way of loading a dishwasher by placing the dirtiest carbohydrate stained dishes in a circular pattern that matches the rotating arms inside dishwasher, as shown in the graphic above, while protein stained plates that need more detergent should be placed around the edges

After studying numerous cycles, experts concluded that the best way to pack your dishwasher is in a circle around the cutlery basket.

Dr Raul Pérez-Mohedano, who led the work at the department of chemical engineering at the University of Birmingham using a technique known as Positron Emission Particle Tracking, also suggested packing the dishes according to the type of stain they contain.

He said that carbohydrate-based stains like potato and tomato need the full force of the jets to get clean, protein based food like dried egg yolk needs more contact with the chemical detergent.

In the study, engineers used radioactive isotopes to monitor the speed and direction that the jets of water travel when the device is in use. 

They found that while the entire interior of the dishwater will get wet during a cycle, it will not necessarily clean everything in the same way.

This explains why in some cases a particularly stubborn piece of burnt food can be washed off in a wash cycle, while other lighter stains can be baked on.

Dr Pérez-Mohedano said: 'The distribution of water inside a commercial dishwasher is very chaotic.

'Areas with a direct impact from the water jets are very localised and these are only able to cover a very small area of all the crockery surface present.'

Instead, most of the water coverage is caused by water falling back down through the dishes, in what Dr Pérez-Mohedano describes as being like 'small waterfalls'.

He found that water took an average of just a tenth of a second to run off plates stacked in a dishwasher.

The findings suggest that the best way to pack a dishwasher would be to place the dishes in a circular pattern to ensure they get hit by the jets of water.

The area between 30cm (11 inches) and 60cm (23 inches) were sprayed with the fastest moving water.

This means that the area immediately above the rotating arms of the dishwasher and in the centre of the top shelf appear to be the best places to put dishes cemented with mashed potato that need the full force of the water.

The study also showed that the areas towards the edges of the dishwasher basket on the bottom shelf tend to be where water travels slower.

It found that the lowest velocities for the water were close to the walls of the dishwasher at a height between 5cm (2 inches) and 20cm (8 inches).

The researchers measured the velocity of water as it moved around the dishwasher when unloaded and loaded as seen in the graphs above. The top line of diagrams show how the water moved when it was sprayed upwards while the bottom line shows how the water fell back down. A and B are unloaded. C-E are loaded

The right way to load a dishwasher is often is often a common source of disagreements among couples

The researchers used Positron Emission Particle Tracking, seen in the picture above, to monitor how radioactive particles moved around inside commercially available household dishwashers as they worked

This means that the detergent will have more time to work on dishes in these areas, making them the ideal place to put egg and custard covered plates.

It is probably the best place to stack any delicate china crockery that should not be exposed to the full force of the water jets.

Loading dishes with food like egg on the bottom towards the outside, as in the picture on the left, will improve the way they are cleaned but overloading a dishwasher will cause food to be baked onto dishes (right)

Dr Pérez-Mohedano, whose study is published in the Chemical Engineering Journal, said that many of the recommended methods of packing offered in the user manuals of commercial dishwashers did not provide the most effective cleaning.

He said: 'Current commercial dishwashers also show a problem of symmetry - while the ejection of water is produced in a circular movement, the distribution of the crockery follows a rectangular pattern.

'This automatically produces areas where the impact of water is going to occur for longer.

'Depending of the soil type to remove, the best procedure to follow varies. For example, cleaning of protein based soils, such as egg yolk, requires of an initial swelling/hydration stage which is typically driven by high alkaline conditions at the beginning of the wash-cycle.

Some curious homeowners have used waterproof GoPro cameras to film inside dishwashers and the results show just how erratic the jets of water can be in some modesl - it is surprising the dishes get cleaned at all

'Afterwards, cleaning occurs by detachment soil layers from top to bottom following hydrolysis reactions.

'Other types of soils based on carbohydrates, like tomato paste, require less chemistry and more mechanical action.

'They are detached in patches of different sizes in a process known as adhesive failure. '

Dr Pérez-Mohedano, who worked with engineers from manufacturer Whirlpool and Procter and Gamble on the study, also cautioned against overloading the dishwasher.

The study found that plates and other dishes essentially create as series of small 'walls' that block the cycle of water around the appliance.

This video shows a more modern dishwasher with the rotating arm similar to that used by the scientists 

The more dishes that are crammed into the dishwasher, the more they stop water reaching from all the areas where they are needed.

Dr Pérez-Mohedano now hopes that the findings can be used to design more efficient and effective automatic dishwashers.

He said: 'In my personal opinion a redesign of the way of distribution of water is necessary.

'There are some ideas out there that have been or are ready to be commercialised.'

Indeed, some manufacturers such as Samsung have attempted to tackle the problem with the flow of water by using moving lines of water jets that create a wall of water that moves through the dishwasher.