Treatment with ozone in the nourishing industry

The use of chambers has become indispensable in the conservation of products, such as the meat, fish, eggs, fruits, cheeses, etc. For that reason, it is interesting to study the problems that could appear, as well as its solutions.

The cold by itself does not solve the problem of the conservation. It immobilizes the rotting germs which can recover all their vigour as soon as they find a favourable climate; it attenuates the loosening of scents, but it does not eliminate them. The deodorization and the disinfection in the refrigerator chambers usually go together.

At first, chambers in which merchandise that gives off strong scents or ethers are store, were deodorized or disinfected by the use of chemical agents that gave tangible results, but hardly controllable. The operation of deodorization and purification was only possible after having evacuated the stored merchandise, since the application consisted on burning the sulphur, by the tablets of threeoximethylene in the chamber to disinfect. But, due to the highly toxic gases which were given off, it was necessary to act effectively. After this operation, an active ventilation of the chamber was indispensable, to eliminate combustion gases, which prolonged still more the time of immobilization of the facilities.

Other methods consist on the evaporation that represents an improvement on the previous method. This vaporization system consists on replacing the combustion for the vaporization of chemical products, especially those with phormol, which do not have any effect but demands also that the operation takes place in a chamber without any merchandise stored, considering that most of the used substances are formed by toxic products that cannot be in contact with the nutritional products.

A system more modern and advanced offers us the use of ultra-violet raises, in the region of the phantom between 2.800 and 2.000 A ., radiations that are able to destroy the microbes, virus and moulds quickly.

A world-wide known scientist, Luis Pasteur, researched the theory of the spontaneous generation of the microbes and demonstrated that the existence of the bacteria in nutritional articles is due to microorganisms transported by the air.

The nutritional substances constitute an excellent means of culture for the microbial colonies, which are developed quickly thanks to the humidity that is generally present in the food storage. The action of ultra-violet raises is fast, avoiding the development of the germs and moulds with a relative short life and a great power of multiplication. This fact can be demonstrated because when the ray emanation is interrupted, the microbial population recovers its vigour quickly.

However, this ray system presents great disadvantages. The first one is based on the little duration of the lamps that produce them, in addition to which, the cathodes still more purified by the technique (lamp of cold cathode), cannot work to low temperatures (between - 35 and - 45 ºC ). For that reason its use is limited in places with a temperature between +5º to - 10 ºC .

Another serious disadvantage is the harmfulness of ultra-violet raises for the human organism, because it causes injuries in the eyes and the skin.

Nowadays it has been verified that the most interesting system is the use of ozone , not only for his low cost and easy obtaining, but for the incredibly effective results that produce.

Ozone in refrigerator chambers reaches both persecuted aims perfectly: the disinfection and the deodorization of the air of the facilities.

In order to fulfill the first aim, the active ozone produced, assures the destruction of numerous microorganisms, which are in the surface of nutritional articles, before its introduction in the chamber. This contamination begins at the same time to the manipulations and transport which take place to room temperature. The refrigeration or the freezing, at that moment cannot do more than to attenuate the bacterial proliferation.

The other aim consists on the total suppression of scents, with the double aim to avoid, on the one hand, the transmission of scents to the chamber and the stored merchandise simultaneously; and on the other hand, the annoyances for the customers and for the workers.

Ozone presents great advantages like the destruction, in an effective way, of ammonia emanations, that is always possible in a cooled chamber by direct expansion.

OZONE IN FRUITS

Fruit is one of the most delicate food in the conservation and storage process. For that reason it must be object of special attention and greater cares.

There are several types of fruit that become rotting in short time. They contain a percentage of water around a 90%, which produces a high relative humidity in the atmosphere of the storage dependencies. These provide the most suitable average for the development of colonies of germs, as well as the helpless for fermentations. This mix of circumstances is the cause of disagreeable scents, the bad aspect and presentation of the fruit and what is more important, after having drained the place is necessary a complete disinfection, to eliminate the germs and moulds of the previous game in order to avoid the possible infection of the new one.

Ozone not only preserves the fruit against the formation of moulds and colonies of bacteria, but also maintains the places disinfected. In this way the expensive disinfections that are required between two consecutive remittances are avoided.

Ozone delays the maturation from 20 to 30%, which allows prolonging the time of storage considerably.

By its deodorization action, Ozone destroys the ethylene gases, that produce the most part of species (the citruses are good example of this fact) and avoid the transmission of flavours from species to others.

It is better to begin the ozonization process in the transport as well as in the packages, which carry a considerable percentage of germs and moulds. From this form, the fruit will arrive at the cameras in perfect state.

In some types is very effective an intermittent ozonization, for example in apples. The metering in these cases oscillates between 1 to 3 p.p.m/v.

It is verified that with the use of Ozone can diminish considerably the losses of weight, at the same time there are not an alteration in the flavour and aroma of the fruit, on the opposite, they will be accentuated.

In this photo it can be seen some clementines damaged by the appearance of the penicilium.
Thanks to a washing with ozone (the clementines of the left side), the propagation of the penicilium is avoided like can be seen in the two clementines of the right that are not dealt with ozone, and therefore, we also avoid the complete damage in the fruit.
By a prolonged treatment with ozone is able to eliminate the penicilium of the fruit, healing the damaged part and avoiding the infection to other pieces.

OZONE IN MEAT AND FISH

Perhaps the meat and the fish are the most perishable products. For its conservation and storage is required cold and freezing; but it is not enough with this. The germs and moulds that inhabit the surfaces and that had been paralyzed by means of the cold of the refrigerator chambers, return to recover their vigour, when merchandise isremoved from the chamber.

The Ozonization should be done from the first process that meat experiment, already from transport, freezing and conservation, to the moment of its consumption.

With Ozone can obtain in addition a better aspect and presentation to the merchandise, preventing the formation of moulds and the rotting. As well as a deodorization of the chambers, with the consequent advantage for the maintenance personnel of these facilities.

It stimulates the digestive action of the oaks, so a whiter meat is obtained acting on muscular and connectives weaves of the same one.

The most advisable concentration is from 2,5 to 3 p.p.m. to a temperature between 1 to 3 ºC and a relative humidity of 90%. A greater concentration would oxidize fats producing disagreeable scent.

In the freezing process a metering from 2 to 3 p.p.m. is recommended although it is enough 1 p.p.m. in later conservation.

The intermittent Ozonization is also very effective, obtaining excellent results with a metering of 5 mg. O 3 /m 3 during two hours daily and 2 or 3 mg/m 3 during the rest of the day.

From this way is obtained a considerable increase in the time of storage and a diminution in the losses of weight.

After 4 days to 3ºC h.r. of 65% (to avoid the patch) a loss of a 10% in weight was observed, while in an Ozonized atmosphere and in the same period of time with a H.R. of 84 to 90 % a loss of 4 % was observed.

EL OZONO EN QUESERÍAS Y LA FABRICACIÓN DE QUESOS

En la curación de los quesos es necesaria una humedad relativa elevada, del 80% al 97%. En estas condiciones el queso es especialmente propenso a la formación de moho que, posteriormente, será necesario eliminar mediante lavado y raspado a fondo, para que no decaiga su aspecto. Estas circunstancias ponen límite a la humedad relativa, tan imprescindible en su curación.

El Ozono , al impedir la aparición de mohos, permite trabajar a humedades elevadas con la consiguiente disminución de la pérdida en peso y el ahorro en el trabajo de raspado. Hace posible una mayor densidad en el almacenaje, al mismo tiempo que suprime los olores evitando las molestias al personal.

La concentración de Ozono requerida en estos casos es de 1 p.p.m./v. Diversos ensayos han manifestado que, con esta dosificación, a una temperatura de 16 ºC y una H.R. del 80 al 85 %, se ha prolongado el tiempo de depósito durante más de 11 semanas, sin que se manifieste la presencia de mohos visibles.

In the treatment of cheeses an elevated relative humidity is necessary, from 80% to 97%. In these conditions the cheese is especially prone to the mould formation that, later, it will be necessary to eliminate thoroughly by means of washing and scraped, in order to maintain its aspect. These circumstances put limit to the relative humidity, very essential in its treatment.

Ozone stops the appearance of moulds and allows working in elevated humidity with the consequent diminution of the loss in weight and the saving in the scraped work. It makes possible a greater density in the storage, at the same time that suppresses the scents and avoids the annoyances to the personnel.

The Ozone concentration required in these cases is of 1 p.p.m./v. Several tests have showed that, with this metering, to a temperature of 16 ºC and a H.R. from the 80 to 85%, the time of deposit has been extended for more than 11 weeks, without the presence of visible moulds is pronounced.

OZONE IN THE EGGS CONSERVATION

The chambers destined to egg storage have to have a relative humidity of 90% in order to avoid the losses and contractions that these experiment through the porosities of the rinds by evaporation.

Since we have said in other occasions, this high humidity constitutes the main problem, whereas it is the average ideal for the formation of moulds and germs that lead to the rotting.

OZONE, once again, comes to solve this problem, preventing this formation and prolonging the period of storage without displaying any diminution in quality and aspect.

During 8 months, eggs submissive to an OZONE metering from 1.5 to 3 p.p.m./v. have been stored, and they have not displayed any difference respect to fresh eggs, natural or cooked, with the particularity that first ones are extents of injurious moulds and germs totally.

ORGANIZATION OF DRYING AND STUFFED CONSERVATION

Respect to this subject, little can be added, that it has not been said already, in which it concerns the humidity atmosphere that is required.

Ozone prevents the flowerings of moulds. After a long time, there can be indications from them, but they lack of all vitality since they die immediately, besides the fact, they can be eliminated by a light brush, saving the expensive work of the washings considerably.

Ozone eliminates the scents, at the same time that accelerates the treatment and the drying of stuffed products, reducing the time that is required for this operation.

SUGAR INDUSTRIES

PACKING ROOM

It shouldn't be forgotten that one of the focuses of infection is located in the package of the merchandise, as much those which are used a single time, as that have a repeated and constant use. In them, the germs and moulds nest, since they find conditions for its development and multiplication, reason why it is very important to disinfect and to sterilize them by means of an effective system: the Ozonization.

TREATMENT WITH OZONE IN THE NOURISHING INDUSTRY