Endocube Hoodwink or Science

[mad fridgie]

coldmetal.
The product itself may well be a very good product simulator, and may well be food safe, never argued this point. Thermal inertia devices have been round since dot one. (and have been used for monitoring)
How ever your thread did not give any technical or engineering proof of why the product saves energy or improves product quality.

I am all for new products and ideas, this what i do for a living. So I ask a question the scientists, in refrigeration and food technology. Here is the reply. (Prof Don Cleland, a world respected refrigeration academic)

Terry

May the Marketers inherit the earth along with the lawyers!

From a quick look and listen, nothing incorrect but a lot of exaggeration and twisting of facts plus a bit of smoke and mirrors.

The key generic issue is whether refrigeration systems should be controlled based on product or air temperatures. Many argue for product temperature but there are argument both ways and on balance I tend to support air temperatures. Some of the arguments and rationale are:

• Putting the thermostat in product (or Endocube) buffers it from air temperature fluctuations so the refrigeration on/off cycle is slowed and a tighter "dead span" on the thermostat can be used. Yes, fewer (longer) on/off cycles can have a equipment maintenance benefit but the energy use benefit should be slight (start power is higher but startup is still a very small faction of the total run-time).
• Control of product temperature is what really matters so you should use it directly as the control parameter; the counter is that you only know what the product temperature is where the probe is (one position in one product), what about the temperature in products in other positions in the room and in other positions in the same product?; the surface of the product will experience greater temperature fluctuations than an internal position so any benefit on product quality are probably illusionary (temperature variability of thermostat looks more stable but air temperature and hence product surface temperature is still cycling; in fact it is possible that magnitude of temp cycles is higher than with air temp control not lower, but because if you only measure temp in product then you are not aware of air temp fluctuations)
• Variability in a refrigerated is with both time and position. Measurement of air temperature (preferable multiple probes) allows this to be "seen" and taken into account with controls. Dampering the thermostat response to changes in air temperature increases the risk of air temperatures somewhere in the room getting very hot or very cold (relative to the average) but undetected; if this occurs the product in these areas may experience unacceptable temperatures. Possible results are partial product freezing if the storage temp is just above the freezing point of the product or some product being too warm.
• Food safety should not be significantly affected by the 2 approaches as the difference in product temps are unlikely to be large and lead to safety issue
• Food quality can be significantly affected as the difference in temp can be large enough to lead to quality degradation e.g. if surface of product partially freezes because on cycle is prolonged. My view is that the longer refrigeration on/off cycles could lead to greater (not less) product surface temperature variation and hence greater quality issues not less.
• Ultimately if the air temp is controlled then the product temp will be OK (once cooled to storage temp). However, the opposite is not true. If a product temp is OK, the air temperature (and hence adjacent product surface temp) may be significantly different for short periods of time potentially leading to quality issues.
• In other words, if you control on product temp then temp control looks good but the actual fluctuations in air and surface temp may be worse than if air temp control was employed; it is just that you are not measuring them anymore.

For me the best solution is use of multiple air probes so variability in room is measured and taken into account PLUS measures to ensure short-cycling and temperature setpoint over-shoot are minimised e.g. modulating temperature control (e.g. BPR or fan speed) rather than on/off liquid supply; avoid excessive oversizing of refrigeration system etc.

Even if you decide to go the product temperature way, why buy an endocube? Just put the thermostat in some product - a lot cheaper.

I hope the above makes some sense. We have been talking about doing a paper at IRHACE and other fora on the issue of product vs air temp control as we are concerned that pracrtice will change without people being aware of the potential downsides.

Cheers
Don

[Tayters]

Prof Don could well be 'The Don' in a Mafia sense!

Even if you decide to go the product temperature way, why buy an endocube? Just put the thermostat in some product - a lot cheaper.

Lots of NHS fridges/freezers have a jelly pack in them. The type you buy for making jelly at home for pudding.

This is acceptable for their readings and tends to dampen the effects of doors open too long, defrosts and all that jazz. When it's reading time they just stick their calibrated probe in the jelly and note the temperature.

It also gives the interior of the cabinet a subtle strawberry, rasberry, blackberry or cherry aroma depending flavour.
Bet an Endocube doesn't do that!

Cheers,
Andy.

[buddy]

I,d like to see the original email to this guy as his reply sounds as though he has been prepped with a loaded question?.

[buddy]

coldmetal.
The product itself may well be a very good product simulator, and may well be food safe, never argued this point. Thermal inertia devices have been round since dot one. (and have been used for monitoring)
How ever your thread did not give any technical or engineering proof of why the product saves energy or improves product quality.

I am all for new products and ideas, this what i do for a living. So I ask a question the scientists, in refrigeration and food technology. Here is the reply. (Prof Don Cleland, a world respected refrigeration academic)

Terry

May the Marketers inherit the earth along with the lawyers!

From a quick look and listen, nothing incorrect but a lot of exaggeration and twisting of facts plus a bit of smoke and mirrors.

The key generic issue is whether refrigeration systems should be controlled based on product or air temperatures. Many argue for product temperature but there are argument both ways and on balance I tend to support air temperatures. Some of the arguments and rationale are:

• Putting the thermostat in product (or Endocube) buffers it from air temperature fluctuations so the refrigeration on/off cycle is slowed and a tighter "dead span" on the thermostat can be used. Yes, fewer (longer) on/off cycles can have a equipment maintenance benefit but the energy use benefit should be slight (start power is higher but startup is still a very small faction of the total run-time).
• Control of product temperature is what really matters so you should use it directly as the control parameter; the counter is that you only know what the product temperature is where the probe is (one position in one product), what about the temperature in products in other positions in the room and in other positions in the same product?; the surface of the product will experience greater temperature fluctuations than an internal position so any benefit on product quality are probably illusionary (temperature variability of thermostat looks more stable but air temperature and hence product surface temperature is still cycling; in fact it is possible that magnitude of temp cycles is higher than with air temp control not lower, but because if you only measure temp in product then you are not aware of air temp fluctuations)
• Variability in a refrigerated is with both time and position. Measurement of air temperature (preferable multiple probes) allows this to be "seen" and taken into account with controls. Dampering the thermostat response to changes in air temperature increases the risk of air temperatures somewhere in the room getting very hot or very cold (relative to the average) but undetected; if this occurs the product in these areas may experience unacceptable temperatures. Possible results are partial product freezing if the storage temp is just above the freezing point of the product or some product being too warm.
• Food safety should not be significantly affected by the 2 approaches as the difference in product temps are unlikely to be large and lead to safety issue
• Food quality can be significantly affected as the difference in temp can be large enough to lead to quality degradation e.g. if surface of product partially freezes because on cycle is prolonged. My view is that the longer refrigeration on/off cycles could lead to greater (not less) product surface temperature variation and hence greater quality issues not less.
• Ultimately if the air temp is controlled then the product temp will be OK (once cooled to storage temp). However, the opposite is not true. If a product temp is OK, the air temperature (and hence adjacent product surface temp) may be significantly different for short periods of time potentially leading to quality issues.
• In other words, if you control on product temp then temp control looks good but the actual fluctuations in air and surface temp may be worse than if air temp control was employed; it is just that you are not measuring them anymore.

For me the best solution is use of multiple air probes so variability in room is measured and taken into account PLUS measures to ensure short-cycling and temperature setpoint over-shoot are minimised e.g. modulating temperature control (e.g. BPR or fan speed) rather than on/off liquid supply; avoid excessive oversizing of refrigeration system etc.

Even if you decide to go the product temperature way, why buy an endocube? Just put the thermostat in some product - a lot cheaper.

I hope the above makes some sense. We have been talking about doing a paper at IRHACE and other fora on the issue of product vs air temp control as we are concerned that pracrtice will change without people being aware of the potential downsides.

Cheers
Don

I,d like to see the original email to this guy as his reply sounds as though he has been prepped with a loaded question?

[mad fridgie]

I,d like to see the original email to this guy as his reply sounds as though he has been prepped with a loaded question?

This the original email.


Hi Don,

I hope all is well!

I thought you may be interested about the claims made by the Endocube product. The product is now being heavily pushed in our neck of the woods.

http://www.endocubeinfo.com/

I would appreciate your thoughts and that of the food technologists if you have the time,

warmest regards

Terry


You can make your own mind up if you think I have prepped the prof!

[buddy]

This the original email.


Hi Don,

I hope all is well!

I thought you may be interested about the claims made by the Endocube product. The product is now being heavily pushed in our neck of the woods.

http://www.endocubeinfo.com/

I would appreciate your thoughts and that of the food technologists if you have the time,

warmest regards

Terry


You can make your own mind up if you think I have prepped the prof!

Looks good to me Terry.