Don’t you know that I heard it through the grapevine…?

Marvin Gaye made this beautiful song…

On two recent visits up country, it became clear that there is a long way to go when it comes to preserving quality after harvest. Unfortunately, the farms have not got much time to play with as repeated yearly quality claims will eventually close them down.

On my visits you keep on finding the same issues. Simple neglected proper design issues.

This time, I was “played out” against two other consultants on a grape farm.

Nice…

The reactions of the deeply knowledgeable staff on the farm were simply great and rewarding, much in the line of our recommendation letters you will find on our website. (www.humiditas.com)

“Jan “Groen Stingel”, a nickname I received recently by my clients, gave 40% more info than the other two and he gave solutions to sort out our problems”. That was the consensus from all involved.

One Golden Rule is valid here: expertise has no value to an audience if you cannot explain it in a simple manner so that the customer understands and can get value out of it…

You are working with living material, cooling something down is not the same as cooling fruit, vegetables-, and flowers.

Now, there are a couple of issues that must be discussed here:

Firstly, what is it with refrigeration consulting engineers and proper Applied Postharvest Technologies: Ignorance, Arrogance, or both?

I will explain it, we all know that to maximize Postharvest quality, people look mainly at temperature control as the most important factor to achieve this and most people these days use mechanical refrigeration. But in most facilities, they all leave it at that. Wrong…!

Most Refrigeration engineers and contractors will ask you some simple questions:

1. How much tonnage do you want to cool?

2. What is the entering temperature?

3. What end temperature do you want and in what time span do you want to achieve that?

Often just asking which product purely to determine the load calculation.

They then calculate your refrigeration capacity to do just that at, preferably, the lowest price.

The general attitude is that they do everything right, every time, and they will tell you” That they engineered everything “right””. So, keep quiet.

Fortunately, there are better cooling plant designs these days, but they are still not covering everything as there is more, far more…

Especially with regards to the Relative Humidity levels in Cold rooms most of the engineers and contractors it really looks like they are either ignorant, arrogant or both…

Refrigeration dries your product out and with too low RH levels combined with the wrong fan airspeed, that simply damages product.

What does your fridge at home do and why to you wrap everything you put in there?

Because it dries your products out! And what is the difference between an “ordinary” fridge and your cold rooms?

But please, do not mention that you want to look at the RH levels. They do not like it and will find three hundred different reasons to talk you out of it. Why? Because they generally do not understand the extend that we bring to the preserving of quality after harvest and, their real reason is that they either do not want to implement bigger coils or better control systems both influencing the quotations directly and put up the cost of the refrigeration plant slightly. But that small cost increase does not weigh up to the advantages you get by gaining shelf life and a better-looking product overall.

Secondly, please start implementing logical, simple principles. For one, each time I visit one of the big, newly designed complexes, engineers keep on installing lights right against the airflow coming out of the blower coils. Please put them perpendicular with relation to the flow coming out of the fans or to put it simple, in a 90° angle. It just makes sense. Simple.

Start turning the blower coils around so that your got an even flow into the cold room. Simple. Blowing the air via the fan in the rooms gives a turbulent and disturbed airflow in the room.

Secondly, why does nobody want to tackle the huge problem that the complete industry is battling, struggling, fighting, and combatting with on an industry scale: Proper airflow designed carton and packaging material?

This has been described and tested in the industry for now nearly 50 years and we are still messing it up.

The initial original proper principle was printed and made public in 1976 by the University of California in Davis. The book is widely distributed but to date, NOBODY does an effort to solve the huge problems the farm has with the “designed” cartons in use…

23 years ago, we already made a proper airflow carton that was tested by Hortec in 2000 with far better results, but the report “disappeared”. Why?

Are we retarded? I don’t think so…

Nature never ever breaks her own laws, not today, yesterday, or tomorrow.

First, there is a process that must be followed when you harvest. The quality of fresh produce in storage depends to a great extent on this process and the humidity. Humidity is more difficult to control than temperature and often does not receive adequate consideration when storages are designed. If the air is too dry, there may be enough water loss to affect the texture and cause visible shriveling or wilting. It can even make the product unsalable.

A real Postharvest specialist knows that the refrigeration, however important, it is in fact only one part of the total equation…

The real goals in the process are these:

· slow ripening, senescence of commodity

· slow activity of decay organisms.

· minimize moisture loss and

· maintain quality.

To achieve that, there are requirements that need to be fulfilled in the cold rooms which of course vary per commodity:

· Generate and maintain steady, low temperatures.

· Hold/support the commodity.

· Allow efficient movement of commodity.

· Ventilation system

· Ethylene- and airborne bacteria control and removal and

· Humidity delivery and control

As a rule of thumb these general recommendations are applicable:

· Temperature: as low as can go without damaging commodity or the building, i.e., avoid condensation (again variable per commodity)

· Humidity: as high as possible again without condensation

· Airflow: as little as possible without starving crop.

And then of course there are other issues such as hygiene, sanitation, disinfection, cleanliness, avoiding sweating, chilling injuries, freezing injuries, chemical injuries and produce compatibility.

If your refrigeration engineer then still tells you that “he has got it right” without taking all these other factors in consideration, the question can be easily asked if it is Ignorance, Arrogance, or both?

In any event, I heard through the grapevine that Humiditas is tried, tested, and proven. Simple.