Category Archives: Refrigeration

Monitoring Food Storage Temperatures – Using tech to help the Chef

TEMPERATURE CONTROL RULES Why is Temperature Control important?

Temperature control is important because harmful bacteria are a hazard present in many of the foods handled in catering businesses.

They also tend to multiply rapidly at temperatures above 5c, the higher temperature and longer the time exposed to the temperature the faster the bacteria growth . As bacteria are invisible to the naked eye and cannot be physically removed from food, all we can do is control their numbers.

There are two main ways in which temperature can be used to achieve this:

  1. We can destroy harmful bacteria, or reduce their numbers, by cooking or reheating and
  2. We can control their growth by keeping food hot or cold.

Lets look at cold.

The following practices are recommended to keep food safe. Your refrigerator should operate at an average of 5°C or below. These temperatures would then be the Critical Limits for Refrigerated Storage. Refrigeration of food temperature of 5°C or below is effective in controlling the quick multiplication of most bacteria in perishable food. It is recommended practice to operate refrigerators and chills at 5°C or below. Freezing of food should be done at -18c.


Time and temperature.

Just because food storage exceeds 5c for a short period of time does not mean that bacteria instantly grows at a rapid rate, your refrigeration being above temperature for a SHORT period of time is not dangerous.

Scientifically it has been shown that bacteria on high risk foods rapidly increase when the food is above 5c for periods exceeding 2 hrs, at 4hrs the food should be discarded.

The issue arises when refrigeration is cool but not cold! Eg A prep cabinet running at an average of 8-10c instead of below 5c. Whilst the bacteria won’t grow as quickly as if the food was at room temperature it will grow and at a dangerous rate, and this is where most hospitality operations get caught out.

I see so many refrigeration units that constantly run in the 5-10c zone, it’s scary. And to be honest in a hot kitchen environment it’s often difficult for small refrigeration units that have doors constantly being open and closed, especially with ingredient wells in the top to maintain correct temperature.

If you are only checking your refrigeration twice a day then you are assuming or guessing that the other 99% of the day the temperature is correct.

Aside from correct food safe procedure, ensuring proper refrigeration temperatures can result in improved shelf life of product and general quality of.

Food manufacturers and major suppliers don’t make guesses or assumptions that all their refrigeration temperatures are correct 24/7/365, they use digital technology to ensure it is, and it’s also far more economical to have technology to this and provided accurate records than employ staff to do so.

Using technology to help Chef’s

The ‘IOT’ world (internet of things) has arrived and its now entering the commercial kitchen space. Basically IOT means things that are connected to the internet , and hopefully add value to our lives.

We can now add temperature sensors to all refrigerated storage areas in the kitchen and have those sensors talk to the internet.

We can tell the sensors how often to talk to the internet and when to be alarmed about a set of data. From that we can direct the sensor to do something.

Basically if the sensor see’s that your coolroom is running at a temperature deemed to be too high for too long we can ask it to tell us, in most cases many people, normally via  SMS text and or email to a smart phone/pad or computer.

As long as the customer has access to the internet they can see current and past history of temperatures of their entire site at the push of a button form anywhere in the world!

With this information the kitchen manager/chef/food safety supervisor can make a decision on what needs to be done, could be a simple as shut the coolroom door properly , or check the food and perhaps discard.

The sensors collect  massive amount of data, basically they are checking your refrigeration temperatures 24/7/365 and then they are storing this data for future access or better still to produce a weekly report as evidence that food storage temperatures are at correct temperatures.

The minimum standard in Hospitality is to collect data samples twice a day , in some health food service sectors it maybe every four  hours. If you  have a lot of fridges this can be a very costly exercise, time wise, time=money. Why pay staff do do it (that may or may not do it correctly if at all!) when technology can do it for you?

Not only can technology do the task for a fraction of the costs of human labour it does it ‘independently ‘ , ‘accurately’ and with lots of data and evidence that can actually be called a ‘fair sample’ of evidence. Twice a day is nothing, it’s less than 1% of the day the other 99% is unaccounted for !

For further information on automated temperature monitoring visit 

Refrigeration Gas Set to change

Refrigeration Gas upcoming changes

As mentioned in previous post from the USA, some dates are starting to surface in the USA with regards to phasing out pretty much all the current refrigerant gasses that are commonly used in industry today, the move forward will be most likely to Hydro Carbon (HC) based gasses.

The first set of dates in the USA  are schedule for as early as March 2017. And whilst this is the USA it should be noted that Europe is on the same path, so its only fair to say that the Australasian market wont be far behind. The simple maths on damage to the ozone and environment by the current gas types compared to the new HC gas types is massively different.

Latest dates that I have seen for the Austyralian Market will see HC standard as of 2018 with an eventual phase out of existing gasses.

Reading between the technical lines, I’m seeing some issues with HC and charge amounts and issues with long distance remote refrigeration systems. The down side to these natural refrigeration gasses is that they are extremely flammable, having said that the amount of gas required in a cabinet is now tiny with HC units, as little a cigerette lighter full!

150gm is the maximum charge amount per cabinet for self contained systems. Where this becomes a problem is on really big refrigeration cabinets open fronted chillers, three door freezers for example they need more gas than this to work properly (achieve correct refrigeration temperatures) . In this example the solution may be to run multiple motors per cabinet which of course will add costs to manufacturer and then retail prices, or it may be a case of using individual cabinets instead of big multi door units.

The other challenge is with Remote and large units , for example Coolrooms. The compressor systems are much larger and require larger amounts of gas, whilst with HC gases the amount of gas required to run a system is massively reduces by at least 50% or more it’s still a large amount of HC Gas, and therefore is deemed a fire risk.

Fire Risk:

These new gasses have one down side, that is they are very flammable! However the amount of gas required to run say a 1 Door cabinet with HC use a tiny, so if an explosion occurred it would be extremely small (think cigarette lighter explosion if you had a naughty teenage/childhood you may recall the size!) so not too much of an issue however there are some recommendations on play to avoid accidental combustion ,  such as no heated burn off condensate trays and not installing near naked flame.

What does this mean for refrigerated drawer systems are char grills and cook tops, is yet to be seen.

Larger systems such as Coolrooms etc the fire risk is greater, Refrigersation mechanics and technicians are currently up skilling now in this area, in some states they may require special HC licence to work on HC refrigeration cabinets.

There is suggestion also that business owners will be required to log there refrigeration systems into the Fire Department also, so they have a data base of where big HC units are in case of fire at that location, they are prepared and warned of the possible dangers.

The cost to the manufacturing industry on changing processes , machinery , engineering and training to the new gases is massive , it will be a deal breaker for smaller companies. Larger international companies have been working with these new gasses now for years, investing millions of dollars of technology into making systems work on minimal gas, and also ensuring the fire risk is mitigated, solutions such as no spark, contactors, bushes, wiring have all been put years of R&D.

The Planet is going to be so much better off the moment we can get all registration and Airconditioning Gases to these new natural HC gasses, but there will be a lot of industry pain getting there.

For the end user consumer:

What does this all mean apart from you being kind to the planet?

MASSIVE RUNING COST REDUCTIONS, which saves you money, efficiency is 25-45% better on these new gas refrigeration systems, if you have multiple refrigeration units in your business this can mean Thousands of dollars of saved RUNING costs.

Inexperienced hospitality operators OFTEN OVER LOOK RUNNING COSTS commercial refrigeration is expensive to run and maintain, especially if you have purchased some cheap knock off copy refrigeration made normally in Asia.

Look at the KW rating on your cabinet (that’s even if they provide one) now times that by your KW$ per charge, now compare that cheap fridge you were considering against a quality cabinet with low KW rating, the money you thought you were saving upfront is elimated in most cases within a year! After that you are losing money each year, not to mention warranty out performance issues.

REFRIGERATION IS THE ONE AREA IN A HOPSITALITY OPERATION THAT ONLY FOOL’S SKIMP ON, I don’t think I can make it any clearer than that! It costs a lot to run, costs more when it breaks down and can cost you dearly if it’s not holding temperature properly and you have a food poisoning/safety issue claimed against your business.

The Flip side is that good commercial refrigeration will last many years, 10+ years is not uncommon on quality brands, compared to cooking equipment that’s probably 2-3 times longer for a busy operation.

RELIABILITY , there are thousands of HC systems already out in the international market place so the data is back on the performance and warranty statistics, Warranty issues have been more than halved in many cases with HC cabinets, so this may mean improved warranty terms going forward, which is a great thing for consumers!

Bottom line:

If you are in the process of choosing new refrigeration you should be discussing  HC and natural refrigerants with your supplier/ designer otherwise you could be in for some costly retro fit or replacement costs in the future.

For further information check out these articles,

you could get in touch with the governing body to learn more, but from what I’ve have seen on that website it’s very typically government, lots of words, links and pages  but hard to find anything really concrete…but then again there are so many types and sectors that use refrigerant gasses, our industry is really a small fish in a pond, its a pretty big field to cover so maybe should cut them some slack…these guys probably are a better resource 

Suffice to say, that what is current, will be the past, so where possible select your refrigeration with HC gas now to save the pain and costs in the short to medium term future.

The confusing situation with all the above statements that needs consideration in your designs and selection of the new Natural refrigeration gasses is noted below. A really good resource to get read for detailed information is ‘The Australian Institute of Refrigeration , Airconditioning and heating.


Hydro Carbon Refrigeration
Hydro Carbon Refrigeration