Title of Invention

A PROCESS FOR EXTRACTION OF AVOCADO (PERSEA AMERICANA) OIL

Abstract

A process for extraction of avocado oil The present invention relates to a process for extraction of avocado oil. The invention is aimed at extracting avocado oil without deteriorating oil quality and without applying heat treatment, chemicals and solvents. There is no deterioration/damage of oil. Process steps are: peeled and deseeded fruit are crushed using mechanical fruit crusher/fruit mill at an rpm of 600 to 750 for a period of 10 to 20 minutes; adding with gripping aid such as saw dust with the crushed material obtained above in a ratio of 1:2 to 3:4 respectively; pressing the above obtained material using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain emulsion and cake, treating the cake with hot water at a temp of 60 to 70°C for a period of 5 to 20 minutes; pressing the above obtained mix using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain residual emulsion .centrifuging the above obtained emulsion at an rpm 12,000 to 15,000 for 10 to 60 minutes to obtain clear green colour avocado oil.

Full Text

The present invention relates to a process for extraction of avocado oil. The invention is aimed at extracting avocado oil without deteriorating oil quality. The fruit is native to Central America. Avocado plant thrive its best in the sub-tropical and tropical region. The fruit is grown in the southern part of India/ The shape of the fruit is pear like with hard thick skin and one round seed. Fruit weight varies between 130 to 500 gm and seed weight between 30 to 60 gm while the average hull weight is 5 gm. Moisture content of the fruit is 83 to 86%. The variation of oil in the fruit is 32 to 45% (dry basis). The variation is mainly attributed to the origin of the fruit. Fatty acid composition also varies with different cultivars, stages of ripening, anatomical region of the fruit as well as place where it grows. The major fatty acids are oleic (18:1), Palmitic (16:0), linoleic (18:2) and palmitooleic (16:1). Linolenic and stearic are also present in traces. The dark green colour crude oil has certain special properties e.g. its emollient in nature, rapid absorption into the skin and its ability to act as natural sunscreen, which make it very useful in the formulation of cosmetic products. Its skin penetrating power is higher than that of corn, almond, soybean and olive oil (1). The product formulation data from US showed a total of 240 products containing avocado oil in concentration range of 0.1 to 50%. The use of avocado oil has been reported in the preparation of cleansing creams, moisturizers, skin care products, hair conditioners, lip sticks, suntan lotion and also in bath oil and make-up base ( 2 ). Refined clear oil is generally preferred for food use. Toxicology test data from human and animal studies using avocado oil as well as cosmetic formulation containing avocado oil ( 3 ) gave a safety assessment for avocado oil. i. Encyclopedia of chemical technology, vol.7,153pp., edited by Kirkothmer, John Wiley & sons, Newyork 1979. 2. FDA Avocado, product Formulation Data, 1976. 3. Path and toxicology, Vol.4 (4), 93-103, 1980. Reference may be made to extraction of avocado oil from adocados (Davis, Richard H., US 4444763, 1984), wherein raw avocado oil is extracted from ripe fruit following maceration, heating, addition of herbaceous siliceous material, and pressure extraction. The draw back is heating, which will denature oil as well as minor constituents of the oil. Reference may be made to process for the recovery of oil from avocado fruit (Curiel, Maurice US 4560568, 1985), where in the avocado fruit is contacted with an acetone solution which extracts the water from the avocado. The drawback is in use of acetone for extraction, since acetone is not of food grade as a solvent. Reference may be made to avocado oil extraction with appropriate technology for developing countries (Bizimana, V. et al. JAOCS, 70(8), 1993, 821-822). Wherein extraction was made at pH5.5 and centrifugal force of 12300 x g. Addition of 5% CaCOa and CaSO4 allowed extraction without organic solvents and at a temperature of 75 to 98°C. The draw backs are in the use of CaCO3, CaSO4 and heat. Heat treatment will denature the oil as well as minor constituents. Chemicals are not allowed for food use oil. Reference may be made to extraction and characterization of avocado oil (Martinez- Nieto, L. et al. Grasas-Y-Aceites, 39(4/5), 1988, 272-277), wherein oil was extracted by pressing, centrifugation and solvent extraction of previously dried sliced avocado had highest-yield. The draw backs are drying and solvent extraction. Drying will denature the oil and presence of minor constituents. Traces of solvent may remain in the solvent extracted oil after removing the solvent. Reference may be made to extraction and refining of oil obtained from dried avocado fruit using a small expeller (Southwell, KH. et al. Tropical Science, 1990, 30(2), 121- 131), wherein oil was extracted from dried fruit. The draw back is drying the fruit. Drying will break down the minor constituents present in oil. Reference may be made to extraction of avocado oil using heat and additional water (Ferreira, E. Revista CERES. 1973, 20(112), 488-489). wherein the avocado pulp is heated to boiling point for 15 min. and oil separated. The draw back is heating the pulp. Heating the oil will deteriorate the oil quality. Reference may be made to extraction technology and industrialization of residues (Sadir, R., Revista - Italiana-delle-Sostanze-Grasse, 1972, 49(2), 90-93), wherein the fruit is first aerobically fermented to release the oil with ethyl alcohol and then extracted with hexane. The draw back is ethyl alcohol and hexane used. Ethyl alcohol is not allowed for food grade oil. Reference may be made to avocado oil production and chemical characteristics (Werman, MJ and Neeman, I. JAOCS, 1987, 64(2), 229-232), wherein avocado oil extraction is influenced by temperature, pH and NaCI concentration, and increased extraction efficiency by centrifugal process. The draw backs are heat treatment and chemicals used. It may deteriorate oil quality. Reference may be made to extraction characterization and prediction of the oxidative stability of avocado oil. (Bizimana, V. Dissertation - Abstracts, International B:58(5) 2195, 1997, 241 pp) wherein oil was extracted from avocado tissues using chloroformmethanol (2:1) and acetone. The draw back is solvent used. The toxic solvents are not allowed for food grade oil. Reference may be made to avocado oil extraction using enzymatic compounds in industrial plants and analytical characteristics of the oil. (Castaldo, A.et al, Rivista - Italiana - delle - sostanze - Grasse, 1997, 74(3) 113-116), wherein commercial enzyme was added at pulping stage and the paste was transferred after 60 min kneading at 40°C to a three stage decanter and subsequently processed in a Pieralisi extraction plant. The draw back is heating at 40°C. Again heating deteriorates the minor constituents of the oil. Reference may be made to aqueous enzymatic extraction of avocado oil from fresh pulp (Freitas, SP. et al., Revue - Francaise - des - corps - Gras, 1993, 40(11/12), 365-371), wherein the peeled avocados were mixed with water at 65°C. The mixture was brought to a temperature optimal for enzymatic reaction and incubated 30 to 180 min followed by centrifugation. The draw back is heating. Heating deteriorates the minor constituents present in the oil. Reference may be made to modified extraction of avocado oil for analysis by refractometry (Lewis, CE. And O' Brien, K. Laboratory practice, 1978, 27(10), 865-866), wherein hard and ripe avocado (2 gm) flesh were dried and extracted the oil into 1-chloronaphthalene in a micro-homogenizer. The ripe fruit was extruded before drying. The draw backs are using solvent and drying. The used solvent is not food grade and drying deteriorates the minor constituents present in the oil. Reference may be made to extraction of avocado oil (Voisin, C. FR 2299399, 1976), wherein the ripe avocado flesh is pulped and very slowly heated on a water bath. The hot material is pressed followed by boiling and cooling slowly. The oil is separated by decanting. The draw back is heating. Heating deteriorates the oil quality as well as minor constituents. Reference may be made to enzymatic extraction of avocado oil ( Buenrostro, M.Lopez- Munguia, CA. Biotechnology Letters, 1986 8(7),505-506), wherein extraction of avocado oil by a mixture of pectinase, alpha-amylase, protease and cellulase. One hour reaction at 65°C followed by dilution and centrifugation. Heating deteriorates the oil quality as well as minor constituents. Reference may be made to a new technique for preparing and refining avocado oil (Jaubert, JN. Fruits, 1970, 25(4), 292-294), wherein a new process for preparing avocado oil is out lined, pressing the pulp, decolorizing and deodorizing, drying in three phases by centrifugation, evaporation and filtration. The draw back is evaporation. Due to evaporation volatile compounds will evaporate. The main objective of the present invention is to provide extraction of avocado oil which obviates the draw backs as detailed above. Accordingly the present invention provides extraction of avocado oil which consists ; a. peeling and deseeding of avocado fruit manually; b. crushing of peeled and deseeded fruit using mechanical fruit crusher/fruit mill at an rpm of 600 to 750 for a period of 10 to 20 minutes; c. adding with gripping aid such as saw dust with the crushed material obtained above in a ratio of 1:2 to 3:4 respectively; d. pressing the above obtained material using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain emulsion and cake. e. treating the cake obtained from above process with hot water at a temp of 60 to 70°C for a period of 5 to 20 minutes; f. pressing the above obtained mix using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain residual emulsion , g. centrifuging the above obtained emulsion from step(d) and step(f) at an rpm 12,000 to 15,000 for 10 to 60 minutes to obtain clear green colour avocado oil. In an embodiment of the present invention the yield of the avocado oil may be 30 to 36 %. In still another embodiment of the present invention the oil may have the following characteristic, i.) odour of the oil - fruity, ii.) colour value of (a) crude Oil - clear dark green (b) refined oil in the range of 0.6 to 1.2 (5R + Y unit, 1 inch cell), iii.) total tocopherol content in the range of 46.1 to 98.92 mg/100 g, iv.) iodine value (Wijs) in the range of 79.8 to 81, v.) saponification value in the range of 190 to 193, vi.) unsap matter in the range of 4.5 to 5.8%, vii.) major fatty acid composition of the avocado oil are oleic 50 to 52%, Palmitic 24 to 25%, linoleic 13.3 to 14.4% and palmitooleic 6.9 to 8.3%. viii.) major triglyceride composition of the oil is GS2 U 26 to 27%, GSU 2 50 to 53% and GU3 19.83 to 20.36%. FLOW DIAGRAM FOR AVOCADO OIL EXTRACTION Washing, Peeling, De seeding, Crushing Pressing, Stage -1 (With gripping aid) Pressing, Stage - II (With Addition of warm water at 60 ~ 70° C) Mix Extract of Stage I + Stage II Water Centrifugation Oil Oil + Cake Cake The following examples are given by way of illustration of the present invention and therefore should not be constructed to limit the scope of the present invention. Example-1 a. Mature avocado fruit was peeled and separated from seed. 5.2 kg peeled fruit was crushed by fruit crusher at 700 rpm 20 min. The crushed fruit was mixed with saw dust in the ration of 3:1 and pressed using Hydraulic Press at the room temperature of 28° C, initially with 500 kg load and 1000 kg load during last few min. b. Pressed oil cake was mixed with 1 lit. hot water (70°C) for 5 min and pressed again at a load of 3000 kg to separate residual emulsion. c. Extracted material (oil-water emulsion) was centrifuged at 12,000 rpm in a cream separator. d. Clear green colour oil was obtained with fruity flavour. e. Fine cake was dried in vacuum shelf drier at 80°C for 8 hrs. The dry fine oil cake was extracted by solvent in soxhlet. f. The final recovery of oil was found to be 30% by pressing. g. Fatty acids methyl ester of avocado oil was analysed by gas liquid chromatography (GLC). Major fatty acids are oleic 50.4%, Palmitic 24.8% linoleic 13.89 % and palmitooleic 7.0%. h. Triglyceride composition of the oil was analysed by HPLC; GS2U 26.5%, GSU2 50%, GU3 20.36%. i. Other characteristics: odour - fruity colour - dark green (crude oil) total tocopherol - 98.92 mg/100 g iodine value (Wijs) -79.81 saponification value -193.0 unsap matter-5.8 % Example - 2 a. Mature avocado fruit was peeled and separated from seed. 5.6 kg peeled fruit was crushed by fruit crusher at 750 rpm 15 min. The crushed material was mixed with saw dust in the ratio of 4:1 and pressed using Hydraulic press at room temperature of 27.5°C, initially 500 kg load and 3000 kg load during last few min. b. Pressed oil cake was mixed with 1 lit. hot water (60°C) for 15 min. and pressed again at load of 3000 kg to separate residual emulsion. ~ c. Extracted material (oil-water emulsion) was centrifuged at 14,000 rpm in a cream separator. d. Clear green colour oil was obtained with fruity flavour e. Fine cake was dried in vacuum shelf drier at 80°C for 8 hrs. The dry fine oil cake was extracted by solvent in soxhlet. f. The final recovery of oil was found to be 36% by pressing. g. Fatty acids methyl ester of avocado oil was analysed by gas liquid chromatography (GLC). Major fatty acids are oleic 50%, Palmitic 25%, Sinoleic 14.4% and palmitooleic 6.9%. h. Triglyceride composition was analysed by HPLC; GS2U 27%, GSU2 50.8%, GU3 20%. i. Other characteristics; odour - fruity colour - dark green (crude oil) total tocopherol content - 98.92 mg/100 g iodine value (Wijs) - 80.0 saponification value -192.8 unsap matter-5.8 % Example-3 a. Ripe avocado fruit was peeled and separated from seed. 5 kg peeled fruit was crushed by fruit crusher at 600 rpm 10 min. The crushed fruit was mixed with saw dust in the ratio of 2:1 and pressed using Hydraulic press at room temperature of 28°C, initially 500 kg load and 2000 kg load during last few min. b. Pressed oil cake was mixed with 1 lit. hot water (65°C) for 20 min and pressed again at a load of 3000 kg to separate residual emulsion. c. Extracted material (oil-water emulsion) was centrifuged at 15,000 rpm in a cream separator. d. Clear green colour oil was obtained with fruity flavour e. Fine cake was dried in vacuum shelf drier at 80°C for 8 hrs. The dry fine oil cake was extracted by solvent in soxhlet. f. The final recovery of oil was found to be 34.5 % by pressing. g. Fatty acids methyl ester of avocado oil was analysed by gas liquid chromatography (GLC). Major fatty acids are oleic 52%, palmitic acid palmitic 24%, linoleic 13.3% and palmitooleic 8.3%. h. Triglyceride composition of the oil was analysed by HPLC: GS2U 26%, GSU2 53%, GU3 19.83%. i. Other characteristics; odour - fruity colour - dark green (crude) total tocopherol content - 46.16 mg/100g iodine value (Wijs) - 81.0 saponification value -191.47 unsap matter - 4.5 % The main advantages of the present invention are- 1. Extraction of oil without applying heat treatment, chemicals and solvents. 2. There is no deterioration/damage of oil. 3. All minor constituents intact. 4. Processing cost is less. 5. Natural colour and flavour useful for cosmetic formulation. 6. Refined oil can be used for food preparation. We Claim: 1. A process for extraction of avocado oil which consists, a. peeling and deseeding of avocado fruit manually; b. crushing of peeled and deseeded fruit using mechanical fruit crusher/fruit mill at an rpm of 600 to 750 for a period of 10 to 20 minutes; c. adding with gripping aid such as saw dust with the crushed material obtained above in a ratio of 1:2 to 3:4 respectively; d. pressing the above obtained material using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain emulsion and cake. e. treating the cake obtained from above process with hot water at a temp of 60 to 70°C for a period of 5 to 20 minutes; f. pressing the above obtained mix using Hydraulic press with a pressure 300 to 500 kg/m2 followed by 1000 to 3000 kg/m2 for a time period in the range of 5- 15 minutes to obtain residual emulsion , g. centrifuging the above obtained emulsion from step(d) and step(f) at an rpm 12,000 to 15,000 for 10 to 60 minutes to obtain clear green colour avocado oil. 2. A process as claimed in claim 1, wherein the yield of the avocado oil is 30 to 36%. 3. A process for extraction of avocado oil substantially as herein described with reference to the example.

Documents:

277-DEL-2003-Abstract-(06-01-2009).pdf

277-DEL-2003-Abstract-(28-11-2008).pdf

277-del-2003-abstract.pdf

277-DEL-2003-Claims-(06-01-2009).pdf

277-DEL-2003-Claims-(28-11-2008).pdf

277-del-2003-claims.pdf

277-del-2003-complete specification (granted).pdf

277-DEL-2003-Correspondence-Others-(06-01-2009).pdf

277-DEL-2003-Correspondence-Others-(28-11-2008).pdf

277-del-2003-correspondence-others.pdf

277-del-2003-correspondence-po.pdf

277-DEL-2003-Description (Complete)-(28-11-2008).pdf

277-del-2003-description (complete)-06-01-2009.pdf

277-del-2003-description (complete).pdf

277-del-2003-form-1.pdf

277-del-2003-form-18.pdf

277-del-2003-form-2.pdf

277-DEL-2003-Form-3-(28-11-2008).pdf

277-del-2003-form-3.pdf