An overview of weekly Blogs

Each week I'm posting any new or interesting information I've picked up during the week.
I will update this Blog with this information and sort the information into relevant sections. You can follow the weekly updates on my Facebook page


Food Production

An article in the Ecologist; whilst farms are pressured into removing hedgerows and ponds to keep out wildlife (which carry pathogens) there is some evidence this may be counterproductive. For example, researchers have found that organic farming encouraged higher biodiversity among soil bacteria, which decreased the number of pathogenic bacteria.


Researchers in Eurosurveillance examined how the seasons affect incidence rates of Campylobacter. Spikes in cases were reported in early to mid-summer with the following reasons attributed: Changing bacterial colonization patterns in flocks kept for human consumption, different food preparation practices (e.g. barbecues), transmission through flies, and increased consumption of fruit and salad.


There are several strains and mutations of Salmonella and the strain that causes typhoid fever is distinct from the strain that causes food poisoning.

Most bacteria cause illness through the release of toxins, however Salmonella itself is toxic.

Salmonella (infective) migrate to the terminal colon in the gut and cause damage to cells which results in diarrhoea.

The battle reads like a Games of Thrones episode; Salmonella infiltrate the body and have the means to stay undetected by the body’s immune system until they have grown into large enough numbers to launch an attack.

When bacteria invade the body, they cause damage to intestinal cells which triggers the body to produce inflammation. The reason for this inflammation is to trap the bacteria, preventing it from migrating to other parts of the body. It also attracts white blood cells to attack the bacteria.

Salmonella can punch through cell walls, however the use of one protein (AvrA) is even more cunning; it keeps the structure of cell walls intact meaning the bacteria can not get through. The upside for the invading bacteria is that it remains undetected, there is no inflammatory response from the body. As a result, the bacteria can grow and build its invasion force until it is ready to strike.

 The intension of the invading force is to spread into other parts of the body; the diarrhoea and vomiting is the body’s next attempt to banish the enemy.

In this weeks New Scientist an article explained how Salmonella can use our immune cells as vehicles to spread around the body (such as the liver) by disrupting electrical signals in the gut. Our intestines have small electrical charges and the immune cells will move towards a negative charge, which means leaving the intestines. Any invading Salmonella residing inside the cells are therefore transported onwards.


The Hygiene Hypothesis. 

An article in The New Scientist this week examined the idea, born in the late 80's that exposure to harmful germs is good for us and that, specifically it reduces the likelihood of developing food allergies. The theory states that rises in allergens directly relate to increased hygiene standards. This is now known to be incorrect, however the media continue to endorse and support the idea.

It is true that contact with microbes ARE critical in the development of our immune systems, however it is not contact with pathogens but rather healthy bacteria that is key. These desirable bacteria are also present in humans, animals and the environment and our decreased exposure (smaller families, changing diets, less breast feeding, less time outside outside) has resulted in the increase of food allergies.

Of course, anyone who regularly watches the programme QI will know that today's 'fact' is often debunked tomorrow. The concern is that most people are regularly fed the hygiene hypothesis by the media and have no knowledge or awareness of an alternative theory that, based on our current knowledge appears to be correct.

WC 25th March: Last week I researched the history of food safety law in England; the adulteration of food (including strychnine in beer during the industrial revolution) was a driving force behind many legal developments.

On a similar theme an article in the New Scientist discussed a 2018 review which found that, on average 30% of fish sold in shops and restaurants is incorrectly labelled. Worst case examples included the accidental selling of toxic pufferfish as monkfish and deliberate mislabelling of fish is estimated to involve billions of global sales.

WC 25th March: The New Scientist published an article about killing bacteria in spaceships (sanitiser is not an option). A metal coating made of layers of silver and ruthenium treated with vitamin C has been developed which, when tested after 19 months was found to have 80 per cent fewer strains than on stainless steel. The material works by producing free radicals than damage cells membranes, exploding the bacteria. It might be a bit far fetched to consider using this material in catering, but then again HACCP made the successful journey from space to your local restaurant.

WC 25th March: (New Scientist) in the readers’ questions a correspondent posted a query on the cleanliness in toilets; if there are three cubicles to choose from which would be the least used (and therefore likely to be least contaminated). Another reader had replied to say they had researched this during their psychology degree and the answer was as follows: most used was the cubicle at the end (proximity to the end wall likely provided a sense of privacy), and least used was the middle cubicle (being bordered by two people being far less private).


I recently came across an EHO report advising an outlet to soak cleaning sponges in bleach which surprised me; I’d always assumed bleach should not be used due to the risk of chemical contamination/tainting.

I decided to investigate this a little further and posted the query on the Facebook group “Food Safety UK”. The general consensus was that bleach should not be used (this also developed into a side track discussion on the use of sponges and dangers of ‘soaking’ but I’ll stick to the main topic here).

Some correspondents made interesting points supporting, in certain circumstances the use of bleach. In particular, a reference was made to the balance of risk; which is greater risk, cross contamination or tainting from bleach? A specific example was given of an ice cream manufacturer who struggled to remove Listeria from the operation and found a range of food grade disinfectants to be ineffective. As a last resort they tried bleaching followed by thorough rinsing and this proved to be successful. They added a bleach deep clean into their weekly cleaning schedule and have never had a positive Listeria sample since.

This also led me to thinking about beer line cleaner and the fact it contains Sodium Hypochlorite (bleach) which means that in effect thousands of outlets do use the chemical in their cleaning programme. Again, the critical control is to thoroughly rinse afterwards.

In general, however the advice was clearly not to use bleach. Firstly, the tainting and secondly the potential to react violently with other materials (e.g. acids and alcohols).

The third, and possibly crucial point is because of its ineffectiveness.

The advice given by one correspondent is that “bleach (sodium hypochlorite) is a chemically unstable compound whose weak chemical bonds cause it to degrade almost as soon as it is manufactured”.

Another group member confirmed “it doesn’t meet BS EN 1276 so it is not to be used as a disinfectant in a food setting.”


Last week I instigated a discussion on the use of bleach in kitchens and as I mentioned at the time there were many related comments regarding the practice of soaking sponges.

This week a group member posted the following advice which I think sums up concerns over ‘soaking’.

“I absolutely agree that soaking sponges is not great practice due to chlorine’s ability to become ineffective when it is bound up with chloramines and the fact that bacteria love moisture. Increasing the Aw in any situation is scary. While on occasions I have come across some premises using sponges to clean, those that do have either a single use procedure or they are used and dried before reuse. It is important to note that these are used to clean and not in the sanitisation process”.



This week I started re-reading a book called error nomics by Joseph T. Hallinan. In the introduction he states that when something goes wrong it is often attributed to human error; airplane crashes (70%), car crashes (90%) and workplace accidents (90%). I don’t know what the percentage for food poisoning is, but I’m guessing it’s pretty high. The problem, as the author puts it, is that once a human is blamed the enquiry usually stops there, but it shouldn’t and if we want to prevent errors, we should look at why humans make errors.

One well known example is the availability heuristic; our behaviour is influenced by how recently we experienced a problem. Think of driving; do you drive above the speed limit? But what happens if you get flashed by a speed camera? Chances are you slow down for a while.

Even experts make mistakes.

I continued reading the book Errornomics this week. Chapter one lists a number of reasons we don’t see things (or miss them), which is obviously relevant to my work as a food safety auditor.

Firstly, we see only a fraction of what we think we see; at normal viewing distances the area of clear vision is about the size of your thumb held at arm’s length.

A second reason was fascinating and frankly terrifying. It is that we, as humans give up quite easily if we don’t regularly find what we’re looking for. For example; during a food safety audit I rarely miss dirt build up on the underside of soap dispensers because I see it so often. But having read this chapter I now think it’s quite likely that, over the years I’ve probably missed a lot of poor practices because they’re rare. This is difficult to admit but consider this:

Radiologists only see a tumour around 0.3% of the time; it’s rare and as a result is often missed. The Mayo clinic did a study on patient X-rays where no tumour was identified but the patient subsequently developed cancer. In retrospect the tumours WERE visible 90% of the time and had actually been visible for days or months. They were just missed.

Similarly, guns and explosives smuggled on board planes are extremely rare, about one gun for every million passengers (in the US). Official figures are not released but in one study at O’Hare international airport undercover agents took bomb materials on board: and screeners missed them 75% of the time.

I’m really hoping that later in the book there is some advice on how to avoid these mistakes!

Why we forget dates

I once conducted a food safety audit with my manager shadowing me. We were in the cellar and I remember checking the date on a barrel of Guinness, checked it was in date and moved on to the next row. My manager then asked my what date was on the Guinness and much to my embarrassment I didn’t have a clue. I couldn’t have told him the month or year of “best before” let alone the actual date. It was a complete blank. This has often concerned me; was I being detailed enough with my checks? Was I really paying attention? When I rechecked the barrel it WAS in date, but was this just luck? At the time I even wandered whether I’d even looked at the date.

Turns out I most likely HAD checked the date and to forget the details was not unusual. As the books’ chapter heading says “meaning matters; details don’t”. This is referring to the way our brains work, it is not saying that details are unimportant; obviously in food safety they are incredibly important. An example given was an experiment on former students of the same class; 73 percent could remember their former classmates faces nearly fifty years later but only 18 percent could remember their names.

A similar experiment was carried out on recalling the details of British pennies; even though we regularly look at them very few people can remember the exact details of the coin when asked to draw the back and the front. Names, the features of coins, the exact dates on beer barrels…. They don’t mean much and so we quickly forget them. OK, so I forgot the date spectacularly quickly, but the theory is still the same; the actual date didn’t really matter and therefore my brain didn’t bother registering the details. This has implications for training too, ensuring information is meaningful to delegates.


Chapter three of the book error nomics included a couple of points I considered very relevant to auditing and training.

When marking exams, I’ve always had a feeling that delegates are unwise to change their answers and prior to taking the test I’ve even warned them on the dangers of doing this. Turns out I was completely wrong. I’m not alone though; most educators, students and test takers assume you should stick with your initial answer and rely on gut instinct. However, "more than seventy years of research on changing shows that most answer changes are from wrong to right, and that most people who change their answers on a test improve their score”. These findings were true across all different types of examination.

Unfortunately, people prefer to stick to their first impression or answers. This is partly due to loss aversion; the pain of losing outweighs the joy of gaining. This leads to Status Quo bias; the preference to keep things as they are. This is a subject I previously covered on a video blog on my website:


The dangers of relying on gut instinct and first impressions are also relevant to auditing. Our first impressions can be influenced by a whole range of psychological biases, from a person’s voice, the clothes they’re wearing (black clothes are associated with power) and whether we’ve eaten.


A survey on Israeli judges hearing parole requests found that the chances of being granted parole start off at 65% at the start of the day then rapidly decline. After lunch, the percentage briefly jumps back up to 65% before dropping again. The survey is not concluding parole decisions depend only on whether the judge has eaten, but evidence suggests it IS a factor.

The danger is we rely heavily on our first impressions and are unwilling to change. As an auditor or inspector our scores, ratings and findings should be evidence based and not reliant on first impressions or hunches.

Unfortunately, auditors and inspectors are human beings and as uncomfortable as it seems we can be affected by the same biases as everyone else. For caters this also highlights the importance of creating confident, professional first impressions.


Chapter Four of error nomics provided some fascinating insight on how our memory’s work, and how we reconstruct memories of past events to put ourselves in a favourable light. This is not the same as conscious lying, it is more like a sub conscious bending of the truth which, as far as we are concerned IS the truth.

In terms of food safety, I found less obvious parallels in this chapter, but a couple of ideas sprang to mind:

1.   If we reconstruct the past to see our actions favourably it is harder to learn from our mistakes.

2.   It is another good reason why any accident or food poisoning investigation should be completed promptly. And it may be harder to uncover the truth at all.

3.   It may affect our relationship with colleagues; particularly if things went wrong in the past. After a few years the memory of our own actions will be become more positive which means our opinion of others may diminish.

4.   It increases the likelihood of us blaming others, sometimes unfairly.

These are the examples presented in the book:

In one experiment at an American college, students were asked to recall their high school grades from a few years earlier 29% recalled it incorrectly with most mistakes (79%) being an upgrade on actual performance.

Students recall accuracy for A’s (89%) was also higher than D’s (29%).

As I write this, I’m casting my mind back to job appraisals I’ve had over the years and it’s true I can recall positive feedback far more easily that any ‘areas for improvement’.



The chapter goes on to explain how this perception can extend to how we literally see ourselves. In an experiment volunteers recognised their own faces in a crowd far more quickly when their image was computer enhanced to be more attractive. What’s more they were more likely to identify the enhanced image as ‘the real me’ when compared to non-enhanced portraits.

Hindsight Bias.

The book makes an important point about the word bias. It does not mean an overtly prejudiced point of view, but rather a “a small nude to our judgement that occurs without being aware of it”.

Hindsight bias is how we reconstruct past events, including our own thoughts and feelings once we know the outcome.

Last weeks Blog examined how people rarely change their mind and when they do, according to Nobel Laureate Daniel Kahneman people “reconstruct their past opinion - they believe they always thought that”.

In terms of food safety and health and safety I’ve known several occasions where individuals and companies have been criticised following an accident; in retrospect it was ‘obvious’ the accident was ‘inevitable’.




As an auditor I’ve given a few low scores over the years and in many cases the manager will blame a chef with a comment such as “I told him the kitchen was dirty!”

Perhaps the manager did, but how often and how forcefully? Did the manager state the urgency and ensure something was done about it? Or was it just a passing comment amongst hundreds of conversations that took place and that only now, in hindsight does the manager remember it as a significant point?

The same may also hold for the Area Manager who warned the site manager he/she needed to be more assertive.

Hindsight bias coupled with a strong tendency to see ourselves in a positive light may result in unfair attribution of blame and makes it harder to learn from mistakes.

Examples of hindsight bias given in erro nomics include historians who focus on specific past events to demonstrate, for example the attack on Pearl Harbour was inevitable. The historian’s arguments are persuasive; however, they have been achieved only by suppressing some facts at the expense of others – a process called creeping determinism.

See the chef, area manager and accident investigations noted above.



In another study gamblers were asked to note their thoughts after the bet was complete. When winning, they focused on how right they were, how inevitable the outcome would be with comments such as “I just knew it”. However, then losing they tended to blame something completely out of their control or a fluke event “I WOULD have won if he hadn’t missed that open goal” etc.

As with all biases (small nudges to our decision making) most of us will have great difficulty acknowledging them and in fact most will deny them. And this can pose dangers.

Say, I’m completing an alleged food poisoning investigation where initial reports suggest chicken was to blame. Now let’s imagine I had conducted an audit at the site a few months earlier and noted the chefs rarely checked the temperature of cooked food and when they did, the probe was not sanitised.



It’s easy for hindsight bias to kick in. It was obvious these poor practices would lead to food poisoning and I’m a pretty good auditor for picking this up. It’s just a shame the site didn’t listen to my advice…… now look what’s happened.

I question the chefs and they don’t even know what the cooking temperature is! I look at their records and I see there are regular gaps in the ‘cooking’ temperature box.

All of this will fail to identify the real cause of the illness; a child sitting on the same table prior to the affected party had been sick.

Fortunately, during audits and investigations we have a series of checks and balances to reduce the likelihood of such mistakes. Unfortunately for the most part of our lives, we don’t.


Before reading any further it is worth looking at the following video. You’ll probably pass the test but the important point to remember is that MANY people don’t. In general, around half of people fail this ‘test’.

Now, watch this second video…… This time I failed! (Well, partly failed. Hint watch it until the end).

How did you get on?



It is possible to be so engrossed in a task we lose awareness of a situation; it is known as inattentional blindness and the reason it happens is there is no such thing as multitasking; we merely switch between tasks.

I previously produced a short-animated video blog on this subject using a real-life example given in the book Errornomics (Chapter Five) and related it to food safety audits.

You can see find it here:

Yes, it is possible to drive a car and hold a conversation with your passenger, but this is because driving has become an automatic skill which doesn’t require conscious attention. How many times have you driven a number of miles and suddenly think “how did I get here? I don’t remember turning off the M1”. This is not as dangerous as it seems; if there is a change in condition, for example the cars in front start to break your conscious mind will be alerted to the situation. Hopefully.

It becomes really dangerous when your mind becomes engaged on another task, for example when the ‘conversation’ turns to an argument, or you look at your phone, or send an e-mail on a laptop (yes, that HAS happened).


A good example given in the book is eating in a restaurant and talking to your friends; no problem. However, try continuing the conversation whilst working out the tip at 15%, that’s not so easy.

I’ve recently conducted several allergen audits; observing chefs as they prepared a meal for an allergen sufferer to ensure they follow the correct procedures. I have rarely observed any failings, however on several occasions the chef has made serious mistakes that could lead to cross contamination. The chefs who used the wrong tongs or prepared raw food close to ready to eat items were always inexperienced or nervous. For a confident, experienced chef the cross-contamination controls are automatic, allowing them to focus on allergen controls. 

I once had the misfortune to conduct a food safety course and the chef managed to serve raw chicken to the delegates (the irony). I don’t know exactly how this happened, but I knew the chef and during an audit a few months earlier I had verified his knowledge and observed him probing food. Perhaps on this one occasion he had become distracted when taking food out of the oven and forgot to check the temperature?

These examples also remind me that, as an auditor I should be aware of the dangers in asking chefs questions during service!

Switching between tasks, as described in the book also creates other problems; one is forgetting what we had planned to do in the first place. In a way this is reassuring. At home I regularly seem to find myself in the kitchen or bathroom and wander aloud “what the hell did I come in here for?” Thankfully this seems to be quite normal.

Errornomics explains that our internal ‘to do’ lists are known as the working memory, but this working memory can evaporate very quickly….. “After only about two seconds, things begin to disappear. And within fifteen seconds of considering a new problem, researchers have shown, we will forget the old problem. In some cases, the forgetting rate can be as high as 40%”.


A related problem is the time it will take to refocus on the original task. In one study of Microsoft workers it took them 15 minutes to return to return full concentration to a serious task after an interruption. This is another good reason (along with contamination risks) why chefs should not have their phones in the kitchen. Say the chef is in the middle of checking dates and he receives a phone call. It could take as long as fifteen minutes before full concentration is regained (partly because the chef, like the Microsoft employees may also check e-mails, social media, weather forecasts etc whilst on the phone) and during that ‘down time’ dates could be missed or, as noted above they may forget what they were meant to be doing entirely.

After reading this chapter I feel fully justified in the extensive ‘to do’ lists I write down (including finishing this week’s blog) and for locking myself in my shed away from my wife and daughter whilst I write the blog to avoid distractions.


Framing is how we look at an issue, often in the wrong way. An example in the book erronomics is wandering into a car park and putting the right key in the wrong car. An example within catering is storing all fish together in the fridge; this is reasonable practice unless ready to eat smoked salmon is stored with raw fish. The product has been ‘framed’ incorrectly and it is something I regularly see during audits.

Another example is the falsification of temperature records. As trainers we often emphasise the importance of due diligence, of proving we did everything possible to keep food safety. On more than one occasion I have watched a chef take food temperatures and write down a figure that ‘proves’ the food was safe, for example 4 degrees C. However, when I double check the actual temperature is way above 8 degrees C. The chef has looked at temperature records in completely the wrong way.


The chapter goes on to explain how our decisions can be affected by all senses. In one experiment researchers examined how shop music affected wine purchasing decisions. When French music was played 40 bottles of French wine were sold, but when German music was played bottles of French dropped to 12 bottles.

This reminds me of training advice I once read; that trainers should not criticise the course venue, food, presentation slides etc. To do so will affect how delegates frame (view) the entire course, and this will in turn affect the learning experience and therefore performance and comprehension.

Time also affects our decisions; when the consequences are far off, we take bigger gambles (e.g. long-term health/diet and exercise) but when consequences are immediate, we are more conservative (e.g. crossing a busy road).

We don’t want staff to take risks when preparing food so emphasising immediate consequences such as food poisoning rather than the long-term consequences such as career development makes sense.

This theory also highlights one limitation of food safety audits and inspections; that standards improve when EHO/audits are expected (immediacy) and decline when no visit is expected (long term).

As a result, many companies carry out ‘wild card’ audits in addition to regular audit cycles.

Managers can also remind staff EHO might visit at any time (emphasising immediacy). I recall one site who previously had an excellent record of internal audits and held a FHR of Five. Neither audit nor EHO were expected for some time, however a customer sent a relatively innocuous complaint regarding stains on coffee mugs. EHO investigated the complaint and whilst there identified several food safety issues…

At the same time, long term consequences can not be neglected. In another experiment two groups were asked to choose rental movies. The first group had to select films to watch immediately and the choices were generally comedies, action movies and similar blockbusters.



The second group were asked to select films to watch in the future and they tended to select more highbrow, serious productions.  Similar experiments were carried out with food; choices for immediate consumption tend to be unhealthier than when planning future meals.

My hunch is that if you ask most chefs to visualise their kitchen in six months’ time and write down a description of the kitchen most answers would include high standards of cleanliness, a food hygiene rating of five, producing good quality food and smooth, efficient services.

I doubt many would write down ‘having a laugh and listening to good music’. However, on entering the kitchen at the start of the day the actions of most chefs would include turning on the stereo and having some banter.

Enjoying work and work relations obviously IS important, however long-term goals are also powerful. It is why the first three of Covey’s Seven habits are ‘be pro-active’, ‘begin with the end in mind’ and ‘putting first things first’. It is why Lewin’s Force Field Analysis reminds us change doesn’t happen by itself and we need to develop a vision for a better alternative.


How information is presented will affect framing and one common practice is anchoring. For example, a shop sign “Four cans for £2.00” will encourage customers to buy four cans, whilst the sign “one can for 50p” will not, even though the figures are the same.

The key to anchoring is the first number as people to tend to process information in order. The fictional examples below are for a company with 500 sites.

All figures are the same but presented in different ways. The first example could be used to celebrate success, the second to warn managers of the negative; that poor results could potentially happen to them.



Celebrate success.

400 sites       =         Five Rating

50 sites         =         Four Rating

25 sites         =         Three rating

2% of sites   =         Two rating

2% of sites   =         One rating

1% of sites   =         Zero rating


A warning to managers.

Zero rating   =         Five sites

One rating   =         Ten sites

Two rating   =         Ten sites

Three rating =         25 sites

Four rating   =         10% sites

Five rating   =         80% sites.


In summary, managers and trainers should be aware of framing; that people (including ourselves) can look at things in the wrong way.

Emphasising the immediate impact of poor practices will help promote safe behaviour. However, developing a vision of future performance is also powerful.

Finally, how we present information is important as people tend to process information in order.


Chapter 7 of the book erronomics: we skim.

I’m going to start this piece with a couple of riddles that are relevant to points contained in the article. The answers to the riddles can be found at the end of the and it is best to confirm the answers before reading on.

1.     “A surgeon witnesses a car crash in which a man dies but his son survives with major injuries. The son is rushed to hospital and requires emergency surgery. The surgeon walks into the operating room and says, “I can’t operate on that boy, he’s my son”. How is this possible?

The second example appeared in a recent edition of The New Scientist and originally appeared in a 2015 paper in The Journal of Problem solving:

2.     “Marjorie and Marsha were born on the same day, same year, same month, same parents, but they’re not twins. How is that possible?”


We pay attention to beginnings.

In one experiment people were asked to read a text and cross out the letter “e” every time they saw one.

It turned out the later the “e” featured in the word, the more likely it was to remain undetected. Not only that, the “e” in the word “the” was very likely to be missed – 32 percent of the time.

This is because our eyes pick up a short word beginning with “th” and our brains do the rest; we don’t examine every letter. Tip; if you are proof reading a document for mistakes it’s better to start from the end and work backwards to avoid the brain creating its own version of what is actually written. We skim.

There are many examples of experts making mistakes such as a newspaper typo that contained the words “rode unicorns” instead of “rode unicycles”. This is a real example.

Experts can be particularly prone to mistakes, mistakes that novices are more likely to spot as they DO tend to focus on each word. The analogy given in the book is “seeing constellations rather than individual stars” and here are a number of examples:

A piece of classical music where a G-natural had mistakenly been written instead of a G-sharp. This remained undetected by proof-readers and musicians for years because in a musical context it HAD to be a G-sharp…… until a musical novice with limited sight-reading ability played the G-natural. She was reading the individual stars.

In 2008 a thirteen-year-old schoolboy corrected a mistake made by NASA and in 2007 a thirteen-year-old from Finland realised that a submarine pictured in a newspaper article was in fact, taken from the film Titanic.

Experts see things as they ought to be, not as they are. In terms of food safety, I remember a course slide with a description of cross contamination as “the transfer of bacteria from raw food to ready to cook food”. It took a confused student with limited experience to point out the error. In addition, it suggests that new, inexperienced staff could have a role to play during internal audits. Usually only managers, supervisors and auditors carry out the checks and in general this makes sense. However, if NASA can miss the obvious then so too can a busy restaurant manager.


Context is important, for example in the first riddle at the start of this piece the context of triplets or quadruplets was not known but once it is pointed out the answer is obvious. Unfortunately, our brains frequently create their own context, as in the second example where most people picture the surgeon as being a man.

A tragic example quoted in errornomics was of a woman who hanged herself in a tree and her suicide remained undetected for more than twelve hours…… because it was Halloween and passers-by assumed it was part of the ‘decorations’.

An example from food safety might be; “a chef used yellow tongs; she took a burger from the fridge and placed it on the grill. The same tongs were immediately used to take cooked chicken from the grill to a customer’s plate”.

Or “smoked salmon was stored in the walk fridge amongst raw, open fish. The site does not serve Sushi.

Both these practices could be deemed to be perfectly safe (although not necessarily best practice) because of context……. The burgers were pre-cooked and stored with other ‘ready to eat’ products in the fridge and the salmon was to be mixed with the raw fish to make a fish pie, cooked to 75C and served.

To avoid mistakes in auditing and food safety management the context must be known, not assumed.

Photographs in newspapers are usually accompanied with a caption to lend context to the picture; it makes sense that food safety workbooks and training presentations do the same.

Context and memory.

When something is out of context it is harder to remember. For example, in one experiment pre-school children were taken for a walk in the park. The day after, the children were sat in the classroom and asked to recall what they had seen. Recollection was poor, however when they were taken back to the park their recollections increased significantly.

In another, British experiment volunteers were asked to memorise a list of words; some on land and others under water in scuba gear.

On average on-land learners remembered 13.5 words when they were tested on land but 8.6 when tested underwater. Scuba divers remembered 11.4 words back under water but 8.4 when on dry land.

Ideally, therefore for online learning to have greater impact on the work place the learning on tablets or phones would take place in the kitchen (providing there are no contamination risks) and not in the office or in the delegates home.

When training I prefer a U shaped or boardroom set up as I feel it encourages greater communication and group participation. However, I may be doing trainees a disservice if the layout is changed to a classroom layout for the exam. The findings certainly suggest they are at a disadvantage if the exam is taken in a completely different room.



Answers to riddles:

1.     The surgeon is the boy’s mother. Many people fail to solve this as they automatically picture the surgeon as being a man.

2.     The two girls are in fact triplets (or quadruplets etc), we just haven’t mentioned their sisters or brothers.

CHAPTER 8: We like things tidy.

Chapter 8 of the book Erronomics is called “We like things tidy”. Unfortunately, this refers to the way we remember rather than the positive virtues of a tidy working environment.

The chapter suggests we carry maps in our heads of real-world places like neighbourhoods and car parks, however the problem is we constantly distort those maps. We straighten curved lines, make odd shapes symmetrical; in shorten we tidy up.

In one experiment, Paris residents to draw a map of their city; and 92 percent of volunteers underestimated the river’s curvature (a similar experiment was conducted with New York taxi drivers).

In another example, psychologist Barbara Tversky gave students two maps; one a false map where North America was positioned directly above south America and the second showing reality; where South America lies to the south east.

Most students chose the inaccurate one as being real, demonstrating how their distorted representation of the world tended to tidy things up.

Managers and chefs’ recollections of their kitchen (or kitchens they’ve previously worked in) may possibly suffer from such distortions! They may recall layout, processes and events as being tidier that they really are.

The fallibility of memory is relevant to training, particularly if there is an exam at the end of the course. People group information together and remember, not individual pieces of information but how it fits into an overall pattern.

Examples given in the book include locating the position of the North Star by first identifying the big dipper, or finding a small village on a map; firstly we refine the search to larger areas such as counties and then locate the village by it’s proximity to a larger town or city.

Inconvenient details tend to be forgotten and facts that do not fit into a coherent whole are very difficult to recall. It is why, from a recall point of view the Seven Principles of HACCP present a problem. We know there are seven principles of HACCP but principle one “identify hazards and identify controls” sounds like two steps.

For many student’s ‘documentation’ a process completed continuously and immediately should logically be placed after ‘validation’ which is a more long-term discipline.

People rationalise and fit information into their own existing ways of seeing the world. When I am writing or delivering courses, I try to present information in a logical order and relate concepts to delegates own experiences. However, I must also be aware what seems a logical order to myself may not be for someone else. It is one reason information is better retained when people discover it themselves; students can then process and assimilate to aid understanding and recall.

One additional finding quoted in the book is interesting but perhaps less relevant to recalling food safety facts; concerns remembering prices. Researchers found that each extra syllable in a price reduces recall by 20%, so for example a figure of 77.51 (eight syllables) is less memorable than 62.30 (five syllables) even though the number of digits are the dame. This may be worth remembering when presenting information; simplifying and limited the number of syllables used.

The chapter goes on to quote studies where students and volunteers exaggerated, missed out or changed information to suit their purposes. For example, students were given a case study of two college roommates (eg Dave and Paul). Both Dave and Paul had positive and negative aspects to their personality (eg hard working but a tendency to spill wine on carpets).

Students then had to write letters, some in a positive aspect (eg job reference) and some in a negative (eg asking them to be kicked out of accommodation). Students regularly attributed negative aspects to the wrong person; for example, explaining how Dave spilled wine on the carpet when it was in fact Paul who committed this act. The letter writers, however, were sure their accounts were factual, in their minds it WAS the truth……… This is a theme I’ve noted several times whilst reading this book.


The chapter also examined the work of Psychologist Stanley Milgram who conducted a series of experiments in the 60’s where volunteers were induced to apparently give electrical shocks under the guidance of men with white lab coats and clip boards.

The part of the ‘victim’ was played by actors, separated by a screen from the volunteer.

At 120 volts the actor would shout the vaults were becoming too painful.

At 150 vaults he would demand the experiment to end.

The men with clip boards would instruct the volunteers to keep turning up the vaults until eventually there was only silence on the other side of the screen. In other words, they had ‘killed’ the actor.

A full 65% of volunteers (both men and women) continued until the very end, just because they were told to by someone in authority.

In terms of risk and security there have been instances of conmen posing as EHO or head office personnel and making off with takings.

In terms of food safety this presents a type of paradox; on the one hand we need staff to follow head office, legal and management directives but on the other we should all retain an element of individual thought. If a manager instructs a chef to use out of date food the chef shouldn’t continue to ‘turn up the voltage’ just because someone in authority has instructed them to do so.

An on that cheerful note, I’ll put my book down for a while and start producing some food safety courses.