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APPLE
The organic market has grown significantly over the past decade around the world and continues to grow. Different products are offered to consumers, mainly fruit and vegetables. We then asked ourselves: How is the microbiota of organic apples different from the microbiota of conventional apples? Is the yield of organic apples lower than conventional apples? We then met Jean Jacques Pécot, an arborist from our sector, from Saint Melaine sur Aubance. He thus explained to us his trades, these controls, the phytosanitary products he used … This approach therefore allowed us to reach our problem which is: How does the microbiota of organic and conventional apples influence on the conservation, the taste and the transformation of the apple into juice?
The apple is one of the favorite fruits of the French, because in addition to being rich in fiber, pectin, vitamins, antioxidants, helping to lower cholesterol, regulating transit, fighting diabetes, reducing the risk of obesity and preventing muscle loss. The apple contains millions of bacteria which are excellent for our intestinal system, allowing good regulation of digestive, metabolic, immune and neurological functions and reducing the risk of infection and inflammation.
Phytosanitary products are used to protect agricultural crops against various threats, in order to limit the risk of crop loss. Some are used to improve the shelf life of fruits and vegetables. To be able to observe a difference in conservation, between an organic apple and a conventional apple, we placed apples in two different incubation media for several days in the dark: In the refrigerator and at room temperature (Note: at the beginning of experience, the apples had been harvested a few days before).
Day 0 of the experiment: organic and conventional apples are placed in the refrigerator and at room temperature respectively; as well as all in the dark.
Day 7 of the experiment: organic and conventional apples placed in the refrigerator did not evolve and remained intact. Organic and conventional apples placed at room temperature have also had no remarkable development observable with the naked eye
Day 26 of the experiment: organic apples, whether at room temperature or in the refrigerator, had a slight deterioration in their skin (withered / wrinkled skin). While conventional apples are still, to the naked eye, intact.
Day 32 of the experiment: the organic apples, whether at room temperature or in the refrigerator, have undergone a marked rot and a very wilted skin. As for conventional apples, they were just starting to have very slightly wilted skin.
Conventional apples have had the same degradation whether stored in the refrigerator or at room temperature. Organic apples have had the same degradation whether stored in the refrigerator or at room temperature. So we can say that it is not the method and therefore the place of conservation that influences the degradation or not of the apple.
What therefore influences the conservation of one apple to another is therefore the treatments carried out beforehand on it. This explains why the conventional apple has a slower degradation than the organic apple.
Conclusion of experiment number 1: Conventional apples have had the same degradation whether they are stored in the refrigerator or at room temperature. Organic apples have had the same degradation whether stored in the refrigerator or at room temperature. So we can say that it is not the method and therefore the place of conservation that influences the degradation or not of the apple.
Conclusion of Experiment 2: Reading the identification plates, we found that the organic apple contained a greater number of microorganisms and its microbiota was more diverse than that of the conventional apple.
Conclusion of experiment number 3: With these results, we can therefore conclude that the conventional apple has a better preservation of its microbiota because few bacteria have grown, either in the refrigerator or at room temperature. In comparison with the organic apple which has had a strong development of its microbiota.
First conclusion of experiment number 4: We found that the juice of organic apples is slightly more acidic than the juice of conventional apples.
Second conclusion of experiment number 4: Organic apples have a higher taste and concentration, in terms of taste, than conventional apples.
General conclusion : With Experiment 2, we observed that the microbiota of conventional and organic apples was not the same, following its results we could see if this difference influences certain parameters.
The first was observed in Experiment 1, where we were able to notice that regardless of the preservation method used, the apples had the same degradation but the organic had it earlier than the conventional one. This first experiment was based on a visual aspect, that is why experiment 3 was useful to observe a potential change in the microbiota of the apple over time. The results of this manipulation showed that yes there was indeed a change because the organic apple had a strong development of its microbiota, while the conventional kept relatively the same.
The second parameter was the acidity, for this we used apple juice. Organic juice has been shown to be more acidic than conventional juice. The last parameter was the taste and again the organic juice tasted more concentrated than conventional juice.
The microbiota of apples therefore affects storage, and also with a difference in acidity and taste with apple juice. This project allowed us to respond globally to our initial problem.
Following all these results, a second more in-depth study should be carried out to really know if the treatments used in conventional agriculture allow a longer conservation of the apple but decrease the acidity and the taste during processing towards apple juice.