Continuous enzymatic process for obtaining virgin oil from coconut pulp

Abstract

The present invention relates to a continuous enzymatic process for obtaining virgin oil and a solid by-product rich in proteins, fibres and hydrolysed carbohydrates from coconut pulp, which comprises the steps: dry grinding of the coconut pulp; formation of an aqueous emulsion by mixing the ground pulp with water; wet grinding of the aqueous emulsion; continuous enzymatic hydrolysis in a jacketed, multi-stage continuously stirred tank reactor; centrifugation of the product obtained in the previous step; separation of the mass obtained in the previous step into three fractions: a fraction (1) comprising the supernatant oil, a fraction (2) comprising the aqueous fraction and a fraction (3) comprising the insoluble part; removal of moisture from fraction (1) to a water value of less than 0.1%, obtaining virgin oil; removal of moisture from fraction (3) to a water value of less than 0.1%, obtaining the solid by-product rich in proteins, fibres and hydrolysed carbohydrates; and recovery of the enzyme from fraction (2).

Description

[0001] DESCRIPTION

[0002] "CONTINUOUS ENZYMATIC PROCESS FOR OBTAINING VIRGIN OIL FROM COCONUT PULP"

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to a continuous enzymatic process for obtaining virgin oil and a byproduct rich in protein, fibre, and hydrolysed carbohydrates from coconut pulp. The invention has application in the field of industrial, food, and cosmetic engineering.

[0005] BACKGROUND OF THE INVENTION

[0006] Within the context of sustainability, green chemistry has advanced toward introducing processes for the bioremediation of polluting technologies, or even introducing clean chemical processes . These actions combine, requiring big innovative effort to launch new products and / or processes with high added value onto the market, providing agribusiness growth through environmentally friendly methods .

[0007] The edible oil industry as a whole, motivated by safety, environmental concerns, and human health concerns, has an urgent need to replace large-scale solvent extraction using hexane with appropriate and environmentally friendly techniques (Bhattachar j ee, P . , R. S . Singhal, and S . R. Tiwari . 2006. Supercritical carbon dioxide extraction of cottonseed oil . Journal of Food Engineering. 79 : 892-989) . Since 2001, Environmental Protection agencies in Europe, the United States, Europe, and other countries have issued strict guidelines for solvent emissions from vegetable oil extraction facilities, providing new incentives for the development of alternative methods of extracting edible oil through environmentally sustainable means .

[0008] The search for a clean and efficient process led to a biotechnological process called enzyme-assisted aqueous extraction, which consists of the enzymatic treatment of oleaginous raw materials, followed by an extraction in an aqueous medium.

[0009] For example, document US3640725 discloses a process for separating nutritional components from soybeans or other oilseeds using enzymatic hydrolysis of the protein.

[0010] Aqueous enzymatic extraction of oils is undoubtedly an emerging technology for the oils and fats industries, as it offers many advantages compared to conventional extraction [Rosenthal, A. , D. L . Pyle, and Niranj an, K. 1996. Aqueous and enzymatic processes for edible oil extraction. Enzyme Microbial Technology 19 : 402-420] . In this case, the use of solvents is eliminated, and this can reduce industrial costs [Barrios, V.A. , Olmos, D.A. , Noyola, R.A. and Lopez-Munguia, C .A. , 1990, Optimization of an enzymatic process for coconut oil extraction. Oleagineux, 45 : 35-42 ] , in addition to enabling the simultaneous recovery of oil and proteins [Caragay, A. B . 1983. Pacing technologies in the fats and oils industry. Journal of American Oil Chemist' s Society. 60 : 1641-1644 ] . The use of enzymes such as cellulases, hemicellulases and pectinases in aqueous enzymatic processes hydrolyses the cell walls of cotyledons . Proteases and carbohydrases are the most used enzymes for this process [Rosenthal, A. , D. L . Pyle, and Niranj an, K. 1996. Aqueous and enzymatic processes for edible oil extraction. Enzyme Microbial Technology 19 : 402-420] .

[0011] Document BRP1100048 describes obtaining of soybean oil and proteins using hydrolytic and proteolytic enzymes .

[0012] Aqueous enzymatic extraction of oil from Carica papaya L . seeds was studied by Puangsri et al . [Puangsri, T . , Abdulkarim, S .M. and Ghazali, H.M. (2005) . Properties of Carica papaya L . (papaya) seed oil following extractions using solvent and aqueous enzymatic methods . Journal of Food Lipids 12 : 62-76] preceded by boiling of the seeds and enzymatic treatment for 24 hours, reaching a maximum yield of 78.8% .

[0013] The use of pectinases and cellulases, with 20 hours of treatment for extraction of soybean oil, dilution 1 : 10 (bran : water ) , at pH 7.0 adjusted with NaOH 2 . ON, showed extraction yield of 84% [Kapchie V.N. , Wei D, Hauck C, Murphy P .A. 2008. Enzyme assisted aqueous extraction of oleosomes from soybeans (Glycine max) . J Agrie Food Chem 56 (5) : 1766-1771 ] .

[0014] Oil extraction from Moringa oleifera seeds, by enzymatic-aqueous process, was performed using commercial enzyme preparations of protease (Neutrase) , a-amylase (Termamyl) , pectinase (Pectinex SP-L) , and cellulase (Celluclast) . The enzymatic treatment lasted 36 hours, with oil yield of 74% [Abdulkarim, S . M. , 0. M. Lai, S . K. S . Muhammad, K. Long, and H. M. Ghazali . 2006. Use of enzymes to enhance oil recovery during aqueous extraction of Moringa oleifera seed oil . Journal of Food Lipids . 13 : 113-130] .

[0015] Document CN1935962 describes a process for obtaining linseed oil through an enzymatic-aqueous process using alkaline protease combined with cellulases, at pH 9.0 adjusted with NaOH solution .

[0016] In turn, document CN1952094 discloses a process for extracting oil from sunflower seeds that employs a mixture of cellulases, using citrate buffer to pH adjustment .

[0017] Lauric oils are oils obtained from coconut trees native to tropical countries, e. g. , coconut oil . In this lauric oil market, coconut oil' s main competitors are palm kernel oil (oil palm) and babassu oil . Global production of lauric oils is about 5.7 million tons . Of this total, coconut oil represents 54%, followed by palm oil, which holds 46% of the world supply [Oil World 2000, Mielke GmbH, cited Hermman, I . ; Nassar, A. M. ; Marino, M. K. M. ; Nunes, R. Coordenagao no SAG do Babagu: Exploragao racional Possivel? Available at : www . fearp .usp .br / egna / resumes / Herrmann . pdf ] .

[0018] In the food and food additives sector, market growth has been significant, with the recent demand for hydrogenated fats and oils free of trans isomers . However, according to information from one of the largest companies in the oleochemical sector - Aboissa Oleos Vegetais - a limiting factor for the oleochemical industry is the fact that there are only about three companies with world-class scale and technology in the sector . The historical deficiency in fractionated acids is explained by the lack of suitable raw materials, as the most abundant oil, soybean, is limited to carbon chains in the C18 range and, therefore, is not applicable for the production of lauric acid. It would be desirable to have a large and stable increase in coconut or babassu oil, with more diverse composition, which would allow for the production of the C12 fraction, which is the most noble .

[0019] The main producers of coconut oil are the Philippines, Indonesia, and India . We verify that Indonesia is the world' s second-largest producer of both palm kernel and coconut oil . Both productions summed, Philippines produces approximately 1.4 million tons of lauric oils, Malaysia another 1.4 million, India 407, 000, Nigeria 188, 000, and Mexico 125, 000 tons (Oilworld, 2000) . Asian countries together produce more than 100, 000 tons of lauric oils per year, while the national average ranges between 5, 000 to 10, 000 tons per year . In this statistic, the rest of the world ends up importing lauric oils, which makes it necessary to update and improve the production processes for these oils, especially continuous production.

[0020] Of the most consumed fatty materials in the world, coconut oil appears with 3.0% and palm oil with 18.0% (OILWORLD, 2000) .

[0021] The usual process used industrially for extracting oil from oilseeds use an organic solvent (hexane) , large-scale pressing, or a combination of both. The pressing process is artisanal, and although it produces a very pure oil, it is uneconomical because it fails to extract all of the oil . In turn, when obtaining oil through solvent extraction, although hexane is very efficient for oil extraction, the nutritional quality of the products is lower when compared to the pressing and / or enzymatic extraction process, thus compromising their quality. Furthermore, operating costs are high, there is still a risk of fire in the plants, and there is the possibility of extracting other undesirable substances, such as gums . Oils produced by hexane extraction have a high content of free fatty acids, waxes, unsaponif iable materials and a dark greenish-brown colour (Juliano, B . O. 1985. Rice Chemistry and Technology, American Association of Cereal Chemists, St . Paul, Minnesota) .

[0022] According to document AP-42 of the United States Environmental Protection Agency (EPA, 1995. Toxics Release Inventory. Available at : www. epa . gov / triexplorer / trends .htm, accessed on December 18, 2010) , vegetable oil extraction plants with hexane represent a potentially important source of hazardous air pollution. Hexane is a volatile organic compound (VOC) that contributes to environmental pollution because it participates in the process known as photochemical smog [Bouchard D, Hdhener P, Hunkeler D. , 2008. Carbon isotope fractionation during volatilization of petroleum hydrocarbons and diffusion across a porous medium: a column experiment . Environ Sci Technol 42 : 7801-7806] .

[0023] According to Section 112 of the Clean Air Act, amended in 1990, hexane is classified as a hazardous air pollutant (HAP) (U. S . EPA, 1995) . It was included in the list of 189 toxic chemicals controlled by the Toxic Substances Inventory (TRI ) (U. S . EPA, 1994 ) . In 2001, the United States Environmental Protection Agency established regulations to control gas hexane emissions due to its carcinogenic potential and environmental harm.

[0024] According to the U. S . EPA' s Solvent Extraction Process Toxic Substances Rule Sheet [EPA, 2001. National emissions standards for hazardous air pollutants : Solvent extraction for vegetable oil production, Environmental Protection Agency. 40 CFR Part 63, Final rule, Federal register 66 : 19005-19026] , solvent losses, which occur at various points in the process, currently range between 0.2 and 2.0 from 0.2 to 2.0 gallons per ton ( 0.757 to 7.57 l / ton) of fortified seeds . The solvent is 100% a volatile organic compound (VOC) , and about 64% is N-hexane .

[0025] In a vegetable oil extraction plant, hexane losses can occur as a result of leaks from stock tanks, transfer pumps and piping, and extraction equipment [EPA-450 / 2-78-035, 1978 ] . In a typical vegetable oil extraction unit, the loss due to volatilization of hexane to the atmosphere is 2 L / ton of processed seed (Freitas et al . , 2010) .

[0026] Hexane losses in the canola vegetable oil extraction process were investigated over a five-month period. The average total loss was 2 L / ton of seeds [Dahlen, J. A. H. and Lindh L . A. , 2009-2010. Hydrogen sulphide and acetaldehyde discharge from a rapeseed extraction plant . Journal of the American Oil Chemist' s Society. 60, 12 DOI : 10 . 1007 / BF02669976 ] .

[0027] Soybean, canola, and sunflower oils are also globally solvent extracted [FEDIOL Guide to good practice on safe operation of Hexane extraction units to limit the likelihood of explosions caused by flammable vapours (application as of January 1, 2007 ) http : / / www. fediol .be / dm / docs /

[0028] 4d7def 43647alf 5d6ca89d72071fadf2 / fediol_06SAF293_215] . According to USDA data [Soy Stats, 2010. World Statistics, available at : http : / / soystats . com / 2010 / page_29.htm] , world production of these three oils in 2009 was 301.3 million tons . Considering an average oil content in the seeds of 25% and an average loss of hexane, per emission, of 2 L / ton of processed seeds, 2, 410, 400 litres of hexane were emitted into the environment during the year, referring only to these three oilseeds .

[0029] In view of the above, it appears that there is a great need in the technique of a process for obtaining virgin oil from oilseeds that uses a renewable and biodegradable raw material, without the use of hexane, with a high yield, so as not to contribute to environmental degradation and that allows obtaining a good quality vegetable oil .

[0030] BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The invention is now described in detail with reference to the attached drawings, in which:

[0032] Figure 1 shows a block flowchart of the general steps of the continuous enzymatic process to obtain virgin oil and a byproduct rich in proteins, fibres and carbohydrates hydrolysed from coconut pulp .

[0033] Figure 2 shows the schematic drawing of the multi-stage continuous stirred-tank bioreactor (CSTR) , which is used in the enzymatic hydrolysis step of the invention process .

[0034] Figure 3 shows the schematic drawing of the multi-stage CSTR bioreactor with a horizontal monobloc configuration, which in one embodiment of the invention is used in the enzymatic hydrolysis step of the invention process .

[0035] Figure 4 shows the schematic drawing of the multi-stage CSTR bioreactor with a vertical monobloc configuration, which in one embodiment of the invention is used in the enzymatic hydrolysis step of the invention process .

[0036] SUMMARY OF THE INVENTION

[0037] The present invention relates to a continuous enzymatic process for obtaining virgin oil from coconut pulp, which comprises the following steps :

[0038] - extraction of water from the coconuts;

[0039] - removal of coconut pulp from the shell;

[0040] - dry grinding of the pulp;

[0041] - formation of an aqueous emulsion by mixing the pulp ground in the previous step with water;

[0042] - wet grinding of the aqueous emulsion obtained in the previous step;

[0043] - addition of 0.1% w / w to 5.0% w / w of enzyme relative to the pulp mass obtained in the previous step;

[0044] continuous enzymatic hydrolysis performed in a j acketed, multi-stage CSTR reactor under constant stirring;

[0045] centrifugation of the product obtained in the previous enzymatic hydrolysis step;

[0046] - separation of the mass obtained in the previous step into three fractions : fraction 1 comprising the supernatant oil, fraction 2 comprising the aqueous fraction, and fraction 3 comprising the insoluble or decanted portion;

[0047] - removal of moisture from fraction 1 to a water value of less than 0.1%, obtaining virgin oil;

[0048] - removal of moisture from fraction 3 to a water value of less than 0.1%, obtaining a solid byproduct rich in proteins, fibres and hydrolysed carbohydrates; and; e - recovery of the enzyme from fraction 2.

[0049] In one aspect of the present invention, the dry grinding of the pulp step is carried out in a knife mill or in grinders until particles between 0.5 and 2 mm are obtained.

[0050] In another aspect of the present invention, the mixing of the dry ground pulp with water to form an aqueous emulsion is carried out in a ratio ranging from 1 : 3 to 1 : 10 m / V.

[0051] In another aspect, the wet grinding step of the aqueous emulsion is carried out in colloidal mills until a particle size between 10 and 100 pm is obtained.

[0052] In yet another aspect, enzymatic hydrolysis is carried out under constant stirring of 50 to 300 rpm, with temperature between 15 and 60 °C and for 6 to 18 hours .

[0053] In one aspect of the invention, centrifugation is carried out at a rotation in the range of 3000 to 10000 rpm for 1 hour to 6 hours .

[0054] In another aspect, the step of separating the mass, obtained in the centrifugation step, into three fractions is carried out by centrifugation, decantation and / or filtration.

[0055] In another aspect of the present invention, the moisture removal step from fractions 1 and 3 is carried out by vacuum drying .

[0056] In yet another aspect, the enzyme recovery step is carried out by ultrafiltration or salt precipitation. In one aspect of the invention, the enzymes used in the enzymatic hydrolysis step are selected from the group comprising enzymes proteolytic, pectinolytic, cellulolytic, amylolytic, glucanolytic, and carbohydrases .

[0057] In another aspect of the invention, the carbohydrase enzymes are selected from the group comprising cellulases, xylanases, alpha-amylases, and beta-glucanases .

[0058] In yet another aspect, the enzymatic hydrolysis step is performed in a horizontal monobloc type or vertical monobloc type CSTR reactor .

[0059] In one aspect of the invention, the vertical monobloc type CSTR reactor is of upward or downward flow.

[0060] In another aspect of the invention, the multi-stage CSTR reactor has separate reaction vessels .

[0061] DETAILED DESCRIPTION OF THE INVENTION

[0062] Given the technical need for vegetable oils in the food industry, as mentioned above, the inventors developed an enzymatic process in aqueous medium and which operates in continuous mode, for obtaining virgin vegetable oil, which uses coconut pulp as a raw material, which is subj ected to enzymatic treatment . The process of the present invention also allows for the production of a solid byproduct rich in protein, fibre, and hydrolysed carbohydrates with numerous applications in the food industry . The aforementioned enzymatic treatment carried out on coconut pulp allows the disintegration of the walls and membranes of the coconut pulp cells, under specific conditions of dilution ( substrate : water ratio) , temperature, incubation time and stirring speed, allowing the release of cellular contents, and thus obtaining virgin vegetable oil, proteins, fibres and hydrolysed carbohydrates .

[0063] In the context of this description, the term "comprising" should be understood as "including, among others" . As such, said term should not be interpreted as "consisting only of" .

[0064] Note that any X value presented throughout this description should be interpreted as an approximate value of the actual X value, since such an approximation to the actual value would reasonably be expected by those skilled in the art due to experimental and / or measurement conditions that introduce deviations from the actual value . Thus, for example, the reference to "80%" means a value of "about 80%" .

[0065] Unless otherwise indicated, the value ranges presented in this description are intended to provide a simplified and technically accepted way of indicating each individual value within the respective range . By way of example, the expression "15% to 25%" or "between 15% and 25%" means any value within that range, for example 15%; 16%; 17%; 18%; 19%; 20%; 21%; 22%; 23%; 24%; 25%; or others, for example, including one decimal place .

[0066] As already mentioned above, in the state of the art, the obtaining of oils from oleaginous raw materials is carried out primarily through pressing methods . These methods, besides being essentially artisanal, use exclusively physical means to rupture the oilseed cell wall and operate in a batch mode . Unlike these methods, the process of the present invention comprises the enzymatic breakdown of coconut pulp to release the oil and other components, such as proteins, fibre, and carbohydrates .

[0067] It is known that oilseed plant cells, like coconut plant cells, accumulate oil in their intracellular spaces, and the use of specific enzymes capable of hydrolysing the cell walls and their membranes causes the release of all lipid content into an aqueous medium. The use of an enzymatic process, such as the one in this invention, is advantageous in that the oil yield is increased without the use of drastic conditions, such as high temperatures and use of organic solvents . Another advantage is the suitability of enzyme complexes to meet the processing requirements under mild conditions .

[0068] Enzymatic processes that operate in batch mode for obtaining vegetable oil from oilseeds are known in the state of the art . These processes have some disadvantages due to the fact that they operate in batch mode, namely: low productivity; have a dead time, when the reactor is not being used in the enzymatic process (loading, unloading, washing time) ; higher costs; and economic limitations on large-scale production.

[0069] To that extent, the present inventors have developed a new enzymatic process that operates in continuous mode and allows a significant increase in productivity, greater process uniformity, better operational control and greater costeffectiveness . Thus, and with reference to figure 1, the continuous enzymatic process in an aqueous medium to obtain virgin vegetable oil and a solid by-product rich in proteins, fibres and hydrolysed carbohydrates, from coconut pulp comprises the following steps :

[0070] - extraction of water from the coconuts;

[0071] pulping - removal of coconut pulp from the shell in industrial removers, with the coconut shell being discarded (solid waste ) ;

[0072] - dry grinding of the pulp in a knife mill or grinders until particles between 0.5 and 2 mm are obtained;

[0073] formation of an aqueous emulsion by mixing the pulp ground in the previous step with water, in a proportion ranging from 1 : 3 to 1 : 10 m / V;

[0074] - wet grinding of the aqueous emulsion, obtained in the previous step, in colloidal mills until a particle size between 10 and 100 pm is obtained;

[0075] - addition of 0.1% m / m to 5.0% m / m of enzyme in relation to the pulp mass to be processed;

[0076] - enzymatic hydrolysis in continuous mode carried out in a j acketed, multi-stage CSTR type reactor ( figure 2 ) , under constant stirring of 50 to 300 rpm, with temperature between 15 and 60 °C and for 6 to 18 hours;

[0077] - centrifugation of the product obtained in the previous enzymatic hydrolysis step, at a rotation in the range of 3000 to 10000 rpm for 1 hour to 6 hours;

[0078] - separation of the mass obtained in the previous step into three fractions : a fraction 1 comprising the supernatant oil, a fraction 2 comprising the aqueous fraction and a fraction 3 comprising the insoluble or decanted part;

[0079] - removal of moisture from fraction 1 by vacuum drying to a water value of less than 0.1%, obtaining virgin oil; - removing moisture from fraction 3 by vacuum drying to a water value of less than 0.1%, obtaining a solid by-product rich in proteins, fibres and hydrolysed carbohydrates; and - enzyme recovery by ultrafiltration or salt precipitation of fraction 2 .

[0080] In the first step of the process, the coconut water is removed and then the fruit is peeled mechanically, using conventional peelers .

[0081] The pulp is removed through industrial strippers, and then dry-ground in a knife mill or grinders, providing particle sizes between 0.5 and 2 mm, being subsequently mixed with process water in a ratio that can vary from 1 : 3 to 1 : 10 m / V (pulp mass per volume of water) . Next, wet grinding is performed in colloidal mills to provide particle sizes in the optimum range of 10 to 100 pm. The process water is the water from fraction 2 after ultrafiltration or salt precipitation to separate the enzyme, that is, it is the enzyme-free water from fraction 2, which is then reused in the process .

[0082] The addition of water after grinding the pulp in a knife mill or grinders is carried out because the second part of the process requires wet grinding to achieve the optimum particle size range of 10 to 100 pm, necessary for enzymatic treatment and also due the fact that occurs in a liquid medium for oil migration to occur .

[0083] After conclusion of the dry and wet grinding steps, the mixture is sent to a CSTR reactor, where enzymes are also added concomitantly and proportionally, through dosing pumps, with proportions ranging from 0.1% w / w to 5.0% w / w of enzyme relative to the pulp mass to be processed.

[0084] The enzymatic hydrolysis step operates in continuous mode and is carried out in a CSTR reactor, in constant flow, j acketed under constant stirring in the range of 50 to 300 rpm, in several stages, which can vary between 2 to 4, with temperature between 15 and 60°C, and duration of 6 to 18 hours .

[0085] In enzymatic hydrolysis, proteolytic, pectinolytic, cellulolytic, amylolytic and glucanolytic enzymes are used in synergy, or complexes containing other carbohydrases, such as cellulases, xylanases, alpha-amylases and beta-glucanases .

[0086] The CSTR reactor operates under atmospheric pressure conditions, being a multi-stage reactor ( figure 2 ) , which can be horizontal monobloc ( figure 3) or vertical monobloc ( figure 4 ) , j acketed, and with stirring. The vertical monobloc CSTR reactor ( figure 4 ) can be of upward or downward flow. In one embodiment, the multi-stage CSTR reactor has separate reaction vessels (not monobloc) , j acketed, and with stirring.

[0087] The material leaving the reactor is sent to the centrifugation stage, operating also continuously at a rotation in the range of 3, 000 to 10, 000 rpm for 2 to 6 hours, depending on the quantity.

[0088] The hydrolysed and centrifuged mass is subsequently separated into three fractions : fraction 1 comprises the supernatant oil, which has a clear and translucent appearance with moisture content of less than 1.5%;

[0089] - fraction 2 comprises the aqueous fraction, which contains hydrolysed proteins and carbohydrates, adding up to a percentage of 1. 0 to 2.0%, in addition to containing the enzyme used in the process;

[0090] fraction 3 comprises the insoluble or decanted portion collected at the bottom of the centrifuge, said fraction rich in proteins and carbohydrates, but still containing moisture .

[0091] Said separation of the hydrolysed and centrifuged mass into three fractions is carried out by means of a solid-liquid separation method, e. g. centrifugation, decantation or filtration .

[0092] Fractions 1 and 3 are sent for vacuum drying to remove moisture, values of less than 0.1% water being obtained at the end of the process .

[0093] To remove moisture from fraction 1, the oily fraction, a vacuum dryer is preferably used, allowing the temperature control during drying to avoid thermal stress on the oil during the process, preventing oxidation.

[0094] To remove moisture from fraction 3, the solid fraction, a steam dryer operating at low temperatures is preferably used, as the sugars darken at temperatures above 40 °C .

[0095] Fraction 2, the aqueous fraction, is reused, both for recycling in the process, as it has a low solids content, and also can be used in the food industry in beverages due to its flavour similar to coconut water .

[0096] The recovery of enzymes remaining in fraction 2 occurs through recycling, which can be done through ultrafiltration, precipitation with salt from fraction 2, or decantation in plate decanters, after the addition of salts .

[0097] Thus, the present invention relates to an enzymatic process that operates continuously and in an aqueous medium, to obtain virgin oil and a by-product rich in proteins, fibres and hydrolysed carbohydrates from coconut pulp, which presents the following advantages compared to the state of the art :

[0098] • does not contribute to environmental degradation, using renewable and biodegradable raw material, the coconut pulp;

[0099] • has high extraction yield when compared to other enzymatic processes, also providing a high-quality oil;

[0100] • it is completely free of organic solvents for the extraction of the lipid fraction, unlike traditional processes for obtaining oil from oilseeds obtained industrially through extraction with hexane;

[0101] • allows extraction of up to 95.0% of the oil present in the coconut pulp, which, although lower than the yield obtained by extracting oil with hexane, which can reach up to 99%, is much higher than the yield obtained by mechanical pressing, which is normally between 40% and 50%, in addition to providing environmental and quality gains that outweigh the difference in yield;

[0102] • does not require degumming during refining, as the substances which constitute gums (proteins, phosphatides, etc . ) are solubilized in water throughout the process and in the gum solubilization step, which does not happen in the case of the process that uses hexane, which requires refining to remove them

[0103] • absence of polluting gas emissions into the environment and low energy and water consumption, as it does not require steam;

[0104] • has a reduced process time when compared to other enzymatic processes for oilseeds;

[0105] • does not generate toxic effluents and risks to workers and the surroundings of the industrial facility; and

[0106] • has potential for application in various industries, such as human and animal food, as well as the cosmetics industry.

[0107] EXAMPLE

[0108] Initially, the coconut water was removed from the fruit, and then 580 kg of coconut pulp was ground in a knife mill continuously for approximately 6 hours and transformed into a flour, that, then, was added to a stirring tank with water inlet, maintaining the required water and wet pulp ratio of 1 : 7 (w / w) , with gentle stirring of 300 rpm. Also continuously, the tank material was pumped to the second grinder (colloidal mill) for wet grinding of the resulting aqueous emulsion and transformation into microparticles with a particle size between 10 and 100 pm.

[0109] After the grinding steps, the pectinolytic and carbohydrase enzymes (50% / 50%) ( 10% of the pulp weight) were added to the mixture obtained (pulp and water) at the programmed inlet of the CSTR reactor, that is, at the reactor feed. A three-stage, of upward flow, vertical monobloc type CSTR reactor, with a hot water jacket and controlled stirring with pump support before and after the process was used. The material was pumped into the reactor at a transfer rate of 600 litres / hour . The residence time was 8 hours, under gentle stirring and temperature of 40 °C .

[0110] Upon leaving the reactor, the product obtained was taken to a three-phase centrifuge that operates for 8 uninterrupted hours, allowing the separation of the hydrolysed and centrifuged material into three phases : an oily fraction ( fraction 1 ) ( 194.88 kg) , an aqueous fraction ( fraction 2 ) (39990.20 kg) and a wet solid fraction ( fraction 3) (439.72 kg) .

[0111] The oily fraction ( fraction 1 ) was sent to a vacuum dryer to remove residual moisture to a water value of less than 0.1%, thus obtaining virgin oil .

[0112] An extraction yield of 96% of the total oil content was observed .

[0113] The aqueous fraction ( fraction 2 ) underwent ultrafiltration to separate the enzyme, recovering 70% of the added enzyme . At this step, the aqueous fraction pass through a membrane filter (polyethersulfone) at a pressure between 2 and 4 bar . The enzyme-free process water was reused in the process .

[0114] The wet solid fraction ( fraction 3) obtained at the centrifugation step underwent drying with gentle heating at 40 °C for approximately 8 hours, until a water value of less than 0.1% was obtained, resulting in a solid byproduct rich in protein, fibre, and hydrolysed carbohydrates .

[0115] It should be noted that although the present invention has been described with reference to its preferred embodiments, many modifications and alternatives can be made by one skilled in the art without departing from the scope of the invention, which is defined by the claims .

Claims

CLAIMS1. A continuous enzymatic process for obtaining virgin oil from coconut pulp characterized in that it comprises the following steps :- extraction of water from the coconuts;- removal of coconut pulp from the shell;- dry grinding of the pulp;- formation of an aqueous emulsion by mixing the pulp ground in the previous step with water;- wet grinding of the aqueous emulsion obtained in the previous step;addition of 0.1% m / m to 5.0% m / m of enzyme in relation to the pulp mass to be processed obtained in the previous step;continuous enzymatic hydrolysis performed in a multi-stage, j acketed, continuously stirred tank reactor (CSTR) and under constant stirring;centrifugation of the product obtained in the previous enzymatic hydrolysis step;- separation of the mass obtained in the previous step into three fractions : a fraction 1 comprising the supernatant oil, a fraction 2 comprising the aqueous fraction and a fraction 3 comprising the insoluble or decanted part;- removal of the moisture from fraction 1 to a water value of less than 0.1%, obtaining the virgin oil;removal of moisture from fraction 3 to a water content of less than 0.1%, obtaining a solidby-product rich in proteins, fibres and hydrolysed carbohydrates; e- enzyme recovery from fraction 2 .

2. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the dry grinding of the pulp step is carried out in a knife mill or in grinders until particles between 0.5 and 2 mm are obtained.

3. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the mixing of dry ground pulp with water for the formation of an aqueous emulsion is in a ratio ranging from 1 : 3 to 1 : 10 m / V.

4. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the wet grinding step of the aqueous emulsion is carried out in colloidal mills until a particle size between 10 and 100 pm is obtained.

5. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the enzymatic hydrolysis is carried out under constant stirring of 50 to 300 rpm, with temperature between 15 and 60 °C and for 6 to 18 hours .

6. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized inthat the centrifugation is carried out at a rotation in the range of 3, 000 to 10, 000 rpm for 1 hour to 6 hours .

7. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the step of separating the mass, obtained in the centrifugation step, into three fractions is carried out by centrifugation, decantation and / or filtration.

8. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the step of removing moisture from fractions 1 and 3 is carried out by vacuum drying.

9. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the enzyme recovery step is carried out by ultrafiltration or precipitation with salt .

10. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the enzymes used in the enzymatic hydrolysis step are selected from the group comprising proteolytic, pectinolytic, cellulolytic, amylolytic, glucanolytic and carbohydrase enzymes .

11. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 10, characterized in that the carbohydrase enzymes are selected from the group comprising cellulases, xylanases, alpha-amylases and beta-glucanases .

12. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the enzymatic hydrolysis step is carried out in a horizontal monobloc type or vertical monobloc type CSTR reactor .

13. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 12, characterized in that the vertical monobloc CSTR reactor is of upward or downward flow.

14. The continuous enzymatic process for obtaining virgin oil from coconut pulp, according to claim 1, characterized in that the multi-stage CSTR reactor has separate reaction vessels .

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