The main destination for Chilean cherries is China, which means that the fruit must withstand long journey times in the best conditions. Considering that cherries are one of the most delicate fruit species after being harvested, it is a real feat that they can withstand 30-40 days of travel to their destination.
This aspect is what draws the attention of the cherry industry worldwide, even those that do not have the challenge of shipping the fruit for many days; the post-harvest of Chilean cherries is watched and admired by many.
We spoke with Héctor García, general manager and co-founder of Laboratorios Diagnofrut, who talked about various aspects of cherry post-harvest.
What do you mean when you say that the 60% and 70% post-harvest are built in pre-harvest? I would like you to explain in more detail what you mean by this.
«It may eventually be the 80%. We must build a fruit, in this case the cherry, that is very noble and all the assembly must be put in place in the pre-harvest. That is, from that moment on, if we do not, in the post-harvest, we cannot fix certain situations that may come from the orchard: nutritional imbalances, a large amount of pathogens, wounds, all those things that I cannot improve in some way in the packing. What I do in the packing is increase or maximize the life time of my fruit, the fruit is dead, it is dying and what I do, in some way, is to stretch that gum as much as possible and keep it; For this, I must have a very large, very specific job in pre-harvest, maintaining good levels of calcium, moderate nitrogen, low amount of pathogen inoculum, a good harvest that has not caused me wounds. Although today the markets ask us for large sizes, but not because of excess growth regulators that will ultimately lead to weaker fruit.", said Hector Garcia.
Should pre-harvest and post-harvest areas then be in conversation?
«Exactly, we must make the pre-harvest and post-harvest teams talk to each other, look at each other's faces and be honest; these are our limitations, these are yours, so we can form from there. I worked in an export company for a long time and more in the post-harvest area, but I was the one to blame because my fruit was spoiling and they didn't see it that way, so what happened? I began to observe the pre-harvest to also define the critical points that were not being addressed there. In other words, even though we are representatives in this case of the post-harvest, but much of the success of the post-harvest has to do with what was done in the pre-harvest.", he added.
From all over the world, people are looking with great interest at the post-harvest process in Chile. A cherry can take 35 or 40 days to reach China, especially in such complex seasons as the ones we had in the two previous seasons. However, today there is a new destination in the sights of producers, exporters and ASOEX, which is India, and which would require a couple more days. How do you see this scenario thinking about the post-harvest of cherries?
«It is complex, it is difficult to address in terms of the fact that they are not used to this type of fruit, from so far away. In other words, the fruit has a shelf life and it will already be well advanced when it arrives in India. But there is another process and that is to get it to the final consumer. For that, several studies have to be done that we have not done, that we should do, such as going there, such as determining whether the fruit arrived at this port, how long it takes and what temperatures it went through. The New Zealanders, who work well ahead of time, did something like this for their kiwis and realized that it was a rather complex market to approach in those terms, because there is a lot of temperature fluctuation. The fruit reached 40 degrees, which could cause us great problems in Chile, we would have to think of other types of packaging eventually or open the bags. It is something that we have to think carefully, I do not see it as so simple that it will be a guaranteed success. But we have to approach it, we have to go to the market, we have to observe, we have to give ourselves time to mature the idea and finally arrive with a product or put limitations on this type of product, it can go there, we can travel this far with the product, it cannot take more than so many days; in short, we structure how it is going to be sold. So I think that there is a beyond the fact that there is hunger in India for this product, we see sitting down and putting all the critical points of our fruit there and how it is going to be marketed successfully. We have to put some brains into this thing.
Regina under the microscope
Something you have been looking at for a long time in the post-harvest is what happens to Regina each season, which is the browning. You are working on a very interesting project that is studying the genes that cause this browning. Can you tell us more about this?
«First, I would like to thank all the members of this project. We are part of the Cherry Committee, several exporters, which is the only way we have today to generate resources quickly. Participating in competitions today can take a year, in which case you can present it and win a research competition with a state subsidy. So we use this model, we are with Avium, we are with the different work groups, the University of Chile is also involved, at the University of Las Americas we finally created this conglomerate with agrochemical companies that gave us the possibility of financing it because this is expensive to do.«.
«What is it all about? This is a project that seeks to decipher the genes that are involved in this accelerated browning, since we have seen that it occurs in other varieties as well. Even in Bing, and the big problem is that it seems that Regina loses a lot of organoleptic quality, that is, consumption quality, and that is where the issue gets complicated. One tends to think that all varieties will end up browning at some point, but in particular Regina goes fast and eventually goes fast and in addition, the flavor decreases, so it is a quality attribute that is lost.«.
«What did we do? We were able to monitor the variety in different areas, thinking about the event occurring and in each of those stages we were extracting RNA that we are currently in the process of reading. We applied a technique called RNA SEC, which looks at everything that was expressed at that time, it is like a photo of which genes are up, which genes were turned off, which ones were turned on and through that we can see which proteins are there, which is the mechanism that is acting so that this process is accelerated or why we have different cases. We had fruit that showed almost no browning and another that at harvest already had 10%«.
Although there is no definitive result today, could it be considered how the agronomic management of the orchard affects it?
«There is a connection with agrochemicals. One part was to see if any product could slow down the process and it didn't go very well, but there are some lights and at the same time knowing which genes may be in this chain or starting the process or what accelerates it, can tell us several things, for example how to block the problem. That would be a bigger technological challenge, but we could do it, discover what the process is that triggers and block it, and there are other things that probably have to do with nutrition, for example the calcium that is present and we can also see that with the genes, because all the genes are there are some genes that generate the cell walls. If they are expressed more it is because the fruit is very firm and as it matures those genes are expressed less and there is no longer as much firmness, that is what happens in all fruits. So maybe we should see those physiological effects as the answer. Therefore, applying more calcium or looking for the way, the right moments, all this information will help us. It's like building a puzzle with different things, what would be the most influential?«.
It will certainly be a tremendous contribution to the industry. We will be very attentive when the results are available and obviously following up with constant publications.
«We have already made several publications. We have held meetings, and we also have to pass them on to producers so they can see how their fruit behaved. We have another big project with FIA (Fund for Agricultural Innovation) and it has to do with viruses. So we have several activities regarding cherries», concluded the general manager and co-founder of Diagnofruit, Héctor García.
