INCORPORATING COLD CHAIN
CONTRIBUTORS
Nature never breaks her own laws …
By Jan Lievens
Jan Lievens
This phrase is one from Leonardo da Vinci , who at the time did a lot of things – but applied postharvest technologies was not one of them .
But what da Vinci said is true , and
especially applies here . In the
September issue of Cold Link Africa , I wrote an article on ignoring problems which can lead to more serious problems . The article sparked some reactions especially when I also stated that the industry must learn to face challenges head-on .
It is true in a lot of cases for a lot of things , and I realise and know that a lot of you did face challenges and tackled them in various ways , and often head-on . One thing however you must remember is that I always write my articles purely from a postharvest perspective .
In general , the Covid-19 pandemic did throw a heck of a lot of challenges around and is still doing so even as I write this article , and my hat goes off to those who adapted and survived . Really .
We have been writing some excellent articles on our speciality : applied postharvest technologies . The word ‘ speciality ’ used in our field should not just be about selling machines , it is about bringing workable and proven solutions to the table .
That fact is important , Cees Nijssen , who sadly passed away in July this year , once said to me : “ The postharvest field applications can either make or break a farm .” He was right . You cannot take a chance with the implementation of technologies that are not proven and do not have a proven track record . It does not matter how big the companies are that want to sell these . Postharvest
Nature proves that even after a good couple of months the grape stem is still in tact on the vine , but when you harvest it dries in a couple of days .
technologies is a very specialised field and the slightest oversight will cost you dearly . Focus is the key factor .
We embarked on a campaign to emphasise the importance of the postharvest philosophy in our three focus areas : fruits , vegetables , and flowers . I fully agree that I have been writing a lot on the table grape industry first and foremost , but you better believe me that much is valid for all fruit .
In fact , it is amazingly simple : your fruit , vegetables or flowers will not reach your client in top quality by chance , but by changing your postharvest approach , philosophy , and procedures . Most farmers worldwide , in general , try to grow the best possible product in the orchard . It is really that simple . 95 % of all her or his efforts are put into this , in some instances for well over eight months . Often the last 5 % of the process gets forgotten and then we are talking about hours after harvest . Yet , the last 5 % is responsible for 99 % of the farm ’ s income .
Let me explain and let us take table grapes as an example as I was invited twice to Egypt to explain our philosophy with regards to grapes . In a discussion on a farm in Egypt on the fruit quality , I went into one of their orchards after the harvest season and took pictures of grapes that were still on the vine after they ‘ cleaned out ’ the vineyard for commercial production . In fact , the orchard was already losing its leaves .
The fruit that was still there , apart from being extremely sweet of course , was still connected via a perfectly healthy stem to the mother plant . When I showed them what was happening , the farmers fell on their backs in disbelief .
Why ? How on earth is that possible ? Why do we have problems when we sell our product ? Why do we have QC problems ? Why ? Why ? That is simply not possible . It is , because nature never ever breaks her own laws .
So why is it that after a good couple of months the grape stem is still intact and when you harvest it is dry after a couple of days ?
Because you ‘ think ’ you are doing the right thing and you cause damage in the initial stages after harvest that is irreversible . Damages done in the cold chain to your product after harvest are cumulative , and irreversible .
For over 50 years , scientists , researchers , universities , technical institutions , and technical research facilities have been studying and writing about it , yet , in the field , it is still happening . Every 10 years someone else is doing a study over the exact same problem .
There is damage and loss that occurs each year , simply because people still take chances and do not look at the root of the problems that occur . You cannot take chances . It is that simple . It took me many years to understand the fact that it is remarkably simple , you must just understand nature . That is all .
Everybody knows the famous industry phrase : an uncooled table grape deteriorates in an hour at 32 ° C , as much as in a day at 4 ° C , or a week at 0 ° C . On face value , that ’ s a very straightforward rule . If you lose time you lose quality . Still , the industry seems to be battling with this concept and a lot of time is lost after harvesting the table grapes in the field .
That is suicidal . If you lose four hours in cooling delays , you lose four weeks ’ shelf life . Simple . In many cases , four hours is putting it mildly . Not only that , but if you know that a grape stem dries out 15 times faster than its berry , you ’ d better take notice .
All too often just a few of the issues at stake here are :
• delays in the orchard
• harvesting at far too high a temperature at the wrong time of the day
• delays in transfer time to the precooler
• improper precooling with low or too low RH
• too high windspeeds
• no bacterial control
• driven by faster output and forgetting temperature
• long packing procedures
• wrong airflow carton design
• delays in cooling
• transport without protection
• containers not at the right temperatures
• inadequate loading procedures
• containers not monitored for temperature and humidity during the voyage
• bad pallets and inadequate packaging material
All of these factors are in the last 5 % in the overall process . Again , and again it is amazingly simple : your fruit will not reach your client in top quality by chance , but by changing your postharvest approach , philosophy , and procedures .
This is valid for all fruits , vegetables , and flowers , not just for table grapes and we
Jan Lievens , born in Belgium , is a graduate civil engineering ( B ) and international senior consultant for engineered applied postharvest technology at UTE South Africa . With over 20 years of experience in this field , he is widely regarded as a specialist in the fruit- , vegetable- and flower industry with regards to humidity , airborne bacteria and ethylene removal , both locally and internationally . Furthermore , he also designed airflow-friendly packaging systems for the industry with proven results .
have proven this over the many years with many customers and with many products .
Keeping on doing the same year after year expecting a change in quality is pure insanity . Recently , a well-known senior table grape technical specialist from one of the top companies dealing with fruit , told me that if the industry would apply our philosophies on the farm after harvest , 50 % of all export quality claims would disappear in South Africa . And then we are talking about a production of around 60 million cartons a year … definitely makes one think .
They already know in Egypt and are talking to us to implement our solutions together with our philosophy . Tried . Tested . Proven . Simple .
A couple of months ago , a well-known agricultural journalist also wanted to write an article on the alleviation of dry stems in the table grape industry and the positive results and success we achieved in this respect . She was blocked in her efforts and ordered to ‘ leave it alone ’.
That is what I meant when I said : “ Face your challenges head-on and look at the root causes of your problems ”. If you want to farm in the future , you have no choice . The farms that supply quality will survive ; the ones that don ’ t will get eaten instead of selling an edible product . And if you are honest you know that the client is already picking out Production Unit Codes ( PUC ) that do not give them stress .
I ’ m sure you don ’ t like stress and you want to avoid it . Again , do something about it , change your attitude on how you look at your business . If you do not , somebody else will . Face the challenge head-on . CLA
COLD LINK AFRICA • January / February 2021 www . coldlinkafrica . co . za 35