Main advantages of almond drying and storage in silos to meet the quality standards demanded by the market.
The almond tree is considered one of the most profitable crops today. Both the social demand and the characteristics of this nut, make it a great production alternative. As with most nuts, in addition to cultivation, it is essential to manage the harvesting and post-harvest processes correctly.
For the optimal maintenance of the product after harvest, special emphasis must be placed on the drying and storage processes, which are the most important and possibly the most delicate in handling this nut, its quality and its value in the market will depend on this.
This process usually begins with the destemming and venting of the almond and later goes to the skinning machine .
For the product to be stored with the best sanitary and conservation guarantees, the humidity level must be lowered to 5-6%.
Traditionally, drying is done in the field (sun drying) and to a lesser extent inside a warehouse. In any case, the relative humidity must be under 65% and the average temperature must be of 25ºC.
Sun drying versus drying in a warehouse
Once the almond is dry, it is stacked in piles for storage. Ideal conditions involve neat, slightly sloping piles (to allow moisture to drain), and good aeration. Again, the relative humidity should be below 65% with a temperature between 10ºC and 15ºC.
If we do not take the appropriate measures we risk the appearance of worms or, worse still , fungi, which could endanger the entire harvest. Aspergillus spp is a cosmopolitan fungus that can quickly colonize large numbers of improperly drying almonds. This fungus produces aflatoxins, a substance that is hazardous to health.
The rancidity of almonds is another problem that may arise. All these problems are linked to the appearance of humidity, which is usually accompanied by heat. Therefore, drying must be done in a ventilated and dry place.
The drying and storage processes described above involve a large amount of work and labor, as well as constant control of the product, in order to ensure that it reaches the market in optimal conditions and without production losses .
It is also found that the surface used for drying and storage has to be very large if we really want to produce a quality product.
For this reason, and taking into account that despite all efforts we may not achieve the desired results – mainly due to atmospheric changes (rain, relents, high temperatures, etc.) – we should modernize the process and approach the idea of drying and storing with the least possible risk for our product.
Advantages of almond drying and storage in silos
At Silos Córdoba we have always innovated and developed new systems to help obtain the best product quality and the optimal maintenance after harvest.
After years of experience in the nuts sector, we can assure that drying almonds in a silo is one of the most efficient systems available today.
If we compare it with sun-drying or with drying in a warehouse, there is a qualitative jump.
– No need for large spaces or a large workforce (a single person can manage a drying and storage plant).
– A more efficient control process without consideration of outside weather influences.
– By having a constant heat input, drying is fast enough to avoid product contamination and it guarantees storage in the best conditions.
How does a drying silo work
To get the best performance from our drying silo we need to adjust the dimensions according to the peeling production capacity of the plant. The drying silo is a hopper silo on a metal structure with a 45º cone.
Inside, there is a slide to prevent the almond from breaking during free fall and a fully perforated counter cone with a connection for air entrance. The counter-cone also allows the discharge of the product according to the FIFO method (first in, first out).
A centrifugal fan connected to a hot air generator is attached to the connecting tube. This hot air passes through the counter-cone drying the almonds.
An air extractor is incorporated in the ceiling to prevent internal condensation and remove excess hot air.
The drying time is somewhat relative, since it will depend on the input humidity of the product, and can range between 8 to 10 hours .
Counter-cone and cone
Silo for almonds storage
The silo is undoubtedly the best option for the storage of almonds and other nuts due to the advantages it provides for their conservation and handling .
- It allows easy ventilation and temperature control if necessary (it is much more complex and expensive to do it in a warehouse).
- Its implementation requires a much smaller space than other storage systems.
- There are no product losses due to breakage, rodents, etc.
- The quality of the product is always assured for its subsequent sale and handling.
- The handling and labor cost is lower than conventional warehouses.
A silo is a good investment if our goal is to have a good product to meet the quality standards demanded by the market.