METHOD FOR PRESERVING RAW MATERIAL CONTAINING CAROTENOIDS

Technical Field

The present invention relates to a method for preserving raw material containing carotenoids, suitable to avoid their degradation in case of storage for prolonged periods. Background Art

The byproducts of the industrial processing of some vegetable products (particularly horticultural products) are widely used; in particular, the byproducts of the processing of tomatoes (peels and seeds) are destined predominantly for zootechnical feeding, for composting and/or for disposal in a landfill. They are rich in carotenoids and in particular in lycopene, a substance of increasing cosmetic and nutraceutical interest (where "nutraceutical" is a neologism which combines the terms "nutritional" and "pharmaceutical" to indicate products derived from various nutrients which have various curative and/or therapeutic functions): investments in research into innovative methods for extracting and purifying lycopene, obtained from industrial recovery of waste material, can lead to considerable economic effects in the same primary sector. One of the specific aspects of the extraction cycle for production consists in the need to collect (gather according to appropriate criteria) the necessary raw material during the approximately 50 days of the tomato picking season for processing and at the same time perform all the activities that are preliminary to the subsequent use of said raw material as a matrix for the extraction of carotenoids (according to any one of the extraction methods).

Lycopene (the carotenoid which presently is the main goal of all extraction processes) is extremely susceptible to degradation upon mere contact with air (the O ₂ contained in the air entails rapid oxidation of the raw material and consequent deterioration of the lycopene) and this

confirmed and unavoidable fact leads to the need to process the raw material directly during the tomato picking and processing (therefore only for 50 days a year).

Of course, the enormous amount of available raw material would make it necessary to provide for pretreatment and drying to be performed in extremely short times: it is therefore necessary to have available large drying units directly associated with processing plants, large storage areas with climate control (maximum 5-10 ⁰ C) and with a modified atmosphere (with O ₂ percentages < 5%) and special systems for transport to the lycopene extraction plant, also having a modified atmosphere and climate control.

This circumstance, combined with the particularly low specific gravity of dried tomato peels (approximately 0.250 g/1), which constitute the main source of the carotenoids of interest, causes substantial technical complications and financial burdens in providing the storage unit which serves the process. Such a low specific gravity in fact entails enormous dimensions for said units. Providing units with the above mentioned requirements, with dimensions suitable for the type of material being processed, entails enormous costs in terms of construction, management and maintenance of the plant. Disclosure of the Invention

The aim of the present invention is to provide a method for preserving raw material containing carotenoids by means of which the degradation over time of the carotenoids is minimized. Within this aim, an object of the present invention is to provide a method for preserving raw material containing carotenoids which can also be applied with small- and medium-size industrial plants.

Another object of the present invention is to provide a method for preserving raw material containing carotenoids which has a low cost, is relatively simple to provide in practice and is safe in application.

This aim and these and other objects which will become better apparent hereinafter are achieved by the present method for preserving raw material containing carotenoids, which consists in mixing the raw material with mixing fluids, subjecting the mixture to a thermal treatment, placing it in appropriate containers, and storing the containers in any environment.

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of a method for preserving raw material containing carotenoids, illustrated by way of non-limiting example in the description that follows.

Ways of carrying out the Invention

A method for preserving raw material containing carotenoids according to the invention consists substantially of a sequence of four consecutive steps to which the raw material is to be subjected. During a first step a), it is necessary to mix the raw material with suitable mixing fluids.

The mixing fluid to be used during said step a) can comprise water and/or an extract of the plants that constitute the raw material. Both can be present individually or can be combined with each other or optionally with other substances in variable percentages.

In particular, the mixture according to step a) can comprise raw material in a percentage which can vary between 25% and 75% and mixing fluid in a proportion which can vary between 25% and 75%. Mixtures comprising raw material in a percentage which can vary between 33% and 66% and mixing fluid in a proportion which can vary between 33% and 66% are found to be particularly effective.

According to an embodiment which is particularly interesting from a practical viewpoint, the raw material might be constituted by tomatoes or derivatives thereof. The industrial processing of tomatoes produces a very large amount of waste material mostly constituted by peels, which are

characterized by a high content in carotenoids (particularly lycopene).

If it is necessary to extract carotenoids (for example lycopene) from tomatoes or from parts thereof (for example peels), the mixing fluid whose use will be more appropriate certainly comprises a certain percentage of tomato juice. Such juice may also constitute all of the components of the mixing fluid or can be diluted with other fluids, particularly water.

Once correct mixing has been performed, one proceeds with step b), by means of which it is necessary to subject the mixture to a thermal treatment. The thermal treatment of the mixture according to step b) comprises conveying the mixture into a sterilizer (the mixture being more specifically pumped into the sterilizer), which has an operating temperature comprised between 90 and 150 ⁰ C: in particular, the method leads to interesting results when the sterilizer operates with temperatures comprised between 102 and 115 ⁰ C. Depending on the case being considered (with the preferred temperature range listed above), it is convenient for the sterilizer to have an operating time which is variable and in particular a sterilizer with a treatment time of 1-6 minutes is assuredly efficient.

In step b), the mixture, at the end of the sterilization treatment, is subjected to cooling, which can be natural, in the environment, or forced, by using suitable refrigeration devices.

Subsequently, in a step c), it will be necessary to package the sterilized and cooled mixture into appropriate containers.

It is convenient for the containers used during the packaging step c) to be food-grade containers with a hermetic seal, of the sealable type. For example, it is possible to use polylaminated material contained in sealed metal drums.

The hermetically closed drums can then be stored in a step d) in any environment. It is appropriate to note that the environment for storing the

containers according to step d) requires no thermal, atmospheric and environmental conditioning in general: this occurs because the mixture that is contained has undergone a treatment which is adapted to preserve its characteristics over time. By means of this method for preserving raw material containing carotenoids it is therefore possible to store extremely large quantities of raw material when said material is abundant and process it later.

With reference for example to the extraction of lycopene from tomatoes and/or their derivatives (such as peels), it is important to note that the tomato picking season lasts approximately 40-50 days only once a year. The ability to store the raw material according to the described method allows to extract the lycopene throughout the year without the risk of rapid degradation of the raw material being processed.

In particular, analysis of the concentrations of lycopene in the packaged mixture, seven months after the packaging of step c), shows a decay which is extremely low and in any case lower than the decay measured on storages of product which has been dried, conditioned and placed in a modified atmosphere.

It has thus been shown that the invention achieves the intended aim and objects.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.

All the details may further be replaced with other technically equivalent ones.

In the exemplary embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.

Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject

of a disclaimer.

In practice, the materials used may be any according to requirements without thereby abandoning the scope of the protection of the appended claims.