Title:  Momordica cochinchinensis (Spreng.) .beta.-carotene and method

United States Patent:  6,770,585

Issued:  August 3, 2004

Inventors:  Vuong; Le Thuy (Davis, CA)

Assignee:  Vitalea Science, Inc. (Davis, CA)

Appl. No.:  211814

Filed:  August 5, 2002

Abstract

The present invention provides a process to extract oil from Momordica cochinchinensis aril to yield an edible oil rich in .beta.-carotene. The process can be carried out without the use of any harmful organic solvents, and provides products containing other carotenoids, such as lycopene, and fiber and vitamin E. This invention provides a bioavailable and stable source of .beta.-carotene, a pro-vitamin A carotenoid, in areas where vitamin A deficiency exists. Products derived from this invention serve as a safe source of antioxidants and nutritional supplement for human and animal consumption, and for the pharmaceuticals and cosmetics industries as well as providing a suitable, effective food additives and colorants.

SUMMARY OF THE INVENTION

The present invention is directed to a method of obtaining carotenoids from Momordica cochinchinensis aril in an oil extract and in the dried aril. In one currently preferred embodiment of the method, a quantity of Momordica cochinchinensis aril is obtained. Aril is removed from seeds. The wet aril can be used as it is, or dried. Drying can be accomplished using conventional drying techniques, such as freeze drying, drum drying, tray drying, sun drying, and spray drying. Drying is preferably in low heat and closed chamber to avoid degradation of carotenoids. In one currently preferred embodiment of the method, wet aril is dried in an electric powered drying box under 60^oC. The dried Momordica cochinchinensis aril preferably has a moisture content in the range of 10-15% by weight. Dried aril can be stored in sealed, dark container for up to 1 year without significant degradation of carotenoids. In one currently preferred embodiment of the method, dried aril is heated slightly before pressing for oil. Heating improves yield of oil, and separation of carotenoids from the plant protein. In another preferred embodiment of the method, an oil expeller is used to produce oil extract. Oil produced can be filtered by using a leaf filter, or centrifuge decanter, or letting the oil rest in a large container overnight, separate out the residue, and then letting the oil go through a leaf filter to reduce water content. Oil extract of Momordica cochinchinensis aril contains from 3000 to 6500 ppm of carotenoids by weight, of which 45-75% are .beta.-carotene. Oil produced from Momordica cochinchinensis aril should be stored in sealed and dark container to avoid rapid degradation and/or oxidation of carotenes. Oil can be kept up to 2 years with minimum loss of .beta.-carotene and without any added preservatives.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to carotenoids fom the aril of Momordica cochinchinensis fruit and to the process of extracting and purifying the oil extract.

In a currently preferred process of producing Momordica cochinchinensis oil extract, the ripen fruit is either hand picked or by mechanical equipment. The fruit can be harvested when its color becomes orange or red. After harvested, fruits can be kept at room temperature for about 2 weeks. The ripe fruit is preferably placed in straw lined containers for further processing and transport. The containers can optionally be stored under refrigerated conditions prior to further processing. The fruit used in the production of oil is inspected for spoilage. Spoiled fruit is separated from the acceptable fruit. The fruit is thoroughly cleaned before any processing occurs.

The processing method for Momordica cochinchinensis aril oil includes seeding, drying, pressing, separation of water, and packaging was designed to retain maximum amount of .beta.-carotene, minimum water activity and low rancidity value in the oil.

Seeding and Drying

Momordica cochinchinensis fruit aril contains between 17,000-35,000 .mu.g/100 g of .beta.-carotene depending on ripeness of the fruit. The amount of lycopene in gac fruit aril varies between 2 to 5 times that of .beta.-carotene (35,000-175,000 .mu.g/100 g), also depending on ripeness of the fruit. About 40% of the dry weight is oil.

The first step in the oil extraction process is scooping out all the aril from the cavity of the fruit into a large container. Separation of seeds from the wet aril can be done mechanically or manually. To remove the seeds manually, the preferred method is to dry the aril by using a variety of methods, including freeze drying, drum drying, tray drying, or sun drying. If a conventional electric powered drying box, or warming oven is used, the wet aril at first is spread on a drying tray. The tray is best made of stainless-steel wire, gaps should not be larger than one inch square. The trays are then placed in the drying box for about 1 hr under 60 deg. C. until the surface of the aril is no longer sticky. At this temperature, the aril can be dried quickly, however, the heat is not high enough to destroy carotenoids. Drying box or warming oven should be closed and dark, as light will also destroy carotenes. The aril can also be covered by clean cloth and sun dried for 4-5 hours, or on a pan over low flame for about 1 hour, however these techniques are expected to incur higher loss of light, heat, and oxygen sensitive carotenoids. Apparently, seeds can also be removed from the wet aril (without drying), however this takes a considerable longer time, and loss of materials is higher. Drying aril before seeding has shown to speed up the seeding process, and reduce water which is necessary for the oil production. Dried aril is then peeled open, and the seeds are removed. The aril after seeded still contains a significant amount of moisture. The oil produced will contain too much water. Seeded aril should be dried again in drying oven under 60 deg C. until moisture content is reduced to about 12-15%. Depending on the size of the drying oven, this step can take up to 2 hours for about 60 kg of fruits. Carotenoids can also be removed from seeds and aril by mixing the aril with alcohol or any organic solvents (ethanol, THF), however, this method is not preferable as it is neccessary to remove all potentially toxic solvents when the oil or aril is used as a food ingredient.

Pressing and Oil Separation

Pressing can be done with a continuous expeller or a small single expeller. If an electric powered oil press is not available, a manual screw press or semi-manual, hydrolic oil press can be used. If a boiler is not attached with the expeller, aril should be warmed slightly in oven (<60 deg C.), for about 10 min, since warming the aril will increase oil yield. Oil yield by the medium size continuous oil expeller is about 20-22%, and of the manual press is about 10% dried weight of aril. The oil produced can be settled in a large container overnight to separate out residue, and further purified by filtering. The filtering equipment preferably consists of, but is not limited to, a centrifuge decanter, a screen filter, a filter press, a leaf filter, reverse osmosis filtration, and any other standard commercial filtration devices. Oil produced by this process should contain between 3000-6500 ppm of total carotenoids, 2500-4500 ppm .beta.-carotene, 500-2500 ppm lycopene, and 150-350 ppm vitamin E (alpha tocopherol). The oil produced by the described process has 0.29% of moisture, pH=4.32, and 0.10% of free fatty acid as oleic. Peroxide Value of the oil is less than 1 meq/kg. Since the oil contains a significant amount of carotenoids, it has an intense red color. It has no odor and a mild nutty flavor. Other available methods can be used to bleach the oil, and/or deodorize to improve palatability or marketability. Oil should be kept in dark, sealed containers and refrigerated to prevent degradation and/or oxidation of carotenoids. If properly stored, oil can be kept for at least 2 years with minimum loss of carotenes, and undetectable rancidity. Oil from Momordica cochinchinensis aril is extremely rich in .beta.-carotene and contains a significant amount of vitamin E. The oil is high in polyunsaturated fatty acids, and low in saturated fatty acids. Momordica cochinchinensis oil can be used in a variety of applications, including, but not limited to cooking oil, salad oil, condiments, seasonings, food colorants, dietary supplements, cosmetics including soaps, skin oil, and animal feedstuff.

The following tables demonstrate nutritional values of oil extract of Momordica cochinchinensis. Values presented are representative of quantitative analyses for this invention, but not inclusive or absolute, since nutrient contents of fruits may vary depending on ripeness, growing regions or climate and post-harvest handling and processing.

EXAMPLES

The following examples are given to illustrate various embodiments which have been made or may be made in accordance with the present invention. These examples are given by way of examples only, and it is to be understood that the following examples are not comprehensive or exhaustive of the many types of embodiments of the present invention which can be prepared in accordance with the present invention.

Example 1

A marinade sauce containing Momordica cochinchinensis oil (Mc. Oil) was prepared having the following ingredients

Example 2

A .beta.-carotene rich skin oil made from Momordica cochinchinensis oil (Mc. oil)

The present invention may be embodied in other specific forms without departing from its essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the forgoing description.

Claim 1 of 8 Claims

What is claimed is:

1. A process to obtain carotenoids from the aril of the fruit Momordica cochinchinensis to yield an oil rich in carotenoids including .beta.-carotene, lycopene, other oil soluble nutrients such as vitamin E, comprising the following steps:

obtaining a quantity of ripen fruits of Momordica cochinchinensis plant;

collecting aril (and seeds) from the cavity of the fruits;

separating aril from seeds.

____________________________________________
If you want to learn more about this patent, please go directly to the U.S. Patent and Trademark Office Web site to access the full patent.