WO2019147121A1

WO2019147121A1 - Process for producing cold pressed palm fruit oil

Info

Publication number: WO2019147121A1
Application number: PCT/MY2019/000002
Authority: WO
Inventors: Nik Suhaimi MAT HASSAN; Ahmad Jaril ASIS; Yosri MOHD SIRAN; Kamal WOK; Norhafizi MD HASHIM
Original assignee: Sime Darby Plantation Intellectual Property Sdn. Bhd.
Priority date: 2018-01-26
Filing date: 2019-01-15
Publication date: 2019-08-01
Also published as: MY187587A

Abstract

Provided is a process for producing cold pressed palm fruit oil with maintained natural antioxidant and bioactive compound contents to be substantially similar to prior to undergoing the process, the process including the steps of cleaning (2) palm fruits until all foreign objects such as trash and dirt are substantially removed, sterilizing (3) the palm fruits from step (a) at temperature of between ambient temperature to 60°C at atmospheric pressure for a time period of between 5 to 240 minutes to produce substantially sterilized palm fruits, digesting (4) the substantially sterilized palm fruits at temperature of between ambient temperature to 60°C at atmospheric pressure for a retention time period of between 5 minutes to 60 minutes to produce substantially digested palm fruits, pressing (5) the substantially digested palm fruits at temperature of between ambient temperature to 60°C and at pressure of between 0 to 80 bar to produce the cold pressed palm fruit oil; and filtration (8) of the cold pressed palm fruit oil to remove gums such as phospholipids and phosphorus.

Description

PROCESS FOR PRODUCING COLD PRESSED PALM FRUIT OIL

FIELD OF INVENTION

The present invention relates generally to a process for producing cold pressed palm fruit oil.

BACKGROUND OF INVENTION

Palm trees bear fruit in the third year after planting and continue producing for about 25 years. Fruit bunches of 4 to 20 kg contain 200 to 2000 individual fruits and are harvested throughout the year. The fruit bunches are transported to palm oil mills where crude palm oil is produced by mechanical and physical extraction processes along with palm kernels from which a further palm kernel oil can be produced. Typically, refined palm oi 1 is produced from palm fruit by a multi-step process as described below. Freshly cut fruit bunches are transported to the oil mill where they are sterilised to inactivate the lipolytic enzymes, loosen the fruit on the bunch, soften the fruit, condition the kernels, and cause protein to coagulate. The sterilisation process uses live steam at about 3 bar. Stripping the fruit from the sterilised bunches (threshing) is carried out in a rotating cage with bars that allow the fruits to pass through, but retain the empty bunches. The loosened fruit is collected by a screw conveyor below the cage and the empty bunches emerge at the end of the cage . The separated fruit is then fed to a digester, which is a cylindrical, steam-jacketed vessel kept at. 90 to 100°C by the injection of live steam. It is fitted with beater arms that break up the fruit and liberate the oil. The digester contents are then fed continuously to a screw press that produces a liquid stream consisting of oil, fines and aqueous phase, and a press cake containing the fruit fibre residue and the palm kernels. The liquid stream is diluted with hot water and is passed to a settling tank via a vibrating screen that returns what it retains to the digester. The oi 1 recuperated from the settling tank is first of all passed through purifier and then dried (crude palm oil). The sludge collecting in the settling tank is passed to a decanter that separates this sludge into a heavy effluent phase and a light, oily phase that is returned to the settling tank. The press cake emerging from the screw press is first of all broken up to separate the fibres from the nuts, then dried, and finally separated pneumatically.

This standard palm oil milling process such as sterilization, clarification and pressing utilises high temperatures (> 90°Cto) produce the crude palm oil. Sterilization at the palm oil mills uses high temperatures such as hot water or pressurized steam for several reasons as stated below:

• high temperatures destroys enzymes which plays a role in oxidation and hydrolysis;

• the cooking of the loose fruits weakens the pulp structure and softens the fruits, thus, making it easier to detach the fibrous matter during digestion process; and ● high temperatures allows oil to be released more readily from the mesocarp of the oil palm fruit.

However, sterilization is the key factor responsible for the deterioration in the natural antioxidants and bioactive compounds as contained in the crude palm oil. Generally, the quality standard of the crude palm oil is dependent on the quality of the fresh fruit bunches (FFBs) and loose fruits arriving at the mills . Therefore, the use of low temperatures to process these FFBs and loose fruits to produce oil can prevent or minimise further deterioration , thus , the palm oil produced are preserved with its natural antioxidants and bioactive compounds.

Crude palm oil undergoes several refining steps to produce refined palm oil. Depending on whether the refined palm oil is produced by chemical (alkaline) refining or by physical refining, these refining steps include degumming , neutralization, bleaching and deodorisation above 200°C (chemical refining) or degumming, bleaching and deodorisation at 240-260'C (physical refining). A typical refined, bleached and deodorized palm oil has all these natural antioxidants and bioactive compounds removed, thus resulting in a clear oil, but it its natural state, crude palm oil is red in colour due to high concentration of carotenes and tocols. Cold-pressed oils refer to oils that are extracted by cold-pressing plant seed with a screw press or hydraulic press. Cold-pressing is used to extract oil from plant seed instead of conventional solvent extraction method because cold-pressing does not require the use of organic solvent or heat (CAC, 2001). Hence, cold-pressing is able to retain bioactive compounds such as essential fatty acids, phenolics, flavonoids and tocopherol in the oils. In general, the term ‘cold pressing’ does not indicate a world-wide fixed temperature limit for all cold pressed oil oils, and besides the temperature, the protection against oxygen and light are important factors as well for the stability. Technically, the temperatures during cold pressing depend on the characteristi cs of the oily fruits and seeds. According to Goranovic (2009), for cold pressed pumpkin seed oil , the temperature of the seeds during processing should not exceed 60°C.

According to Sue-Siang Teh et al . , (2012) (Physicochemical and quality characteristics of cold-pressed hemp, flax and canola seed oils) Journal of Food Composition and Analysis 30 (2013) 26-31, the need for widely usable and easily available bioactive lipids and natural antioxidants continues to grow and over the last few years, increased interest in cold pressed oils has been observed as these oils have high nutritive properties . Cold pressing is a technology for seed oil production, which involves no heat treatment or chemical treatment. Cold pressing also involves no refining process and may contain a higher level of natural antioxidants .

US20020028272A1 describes the production of enriched edible vegetable oils comprising the mixing of pre-shelled oil -seeds with medicinal components from various and cold pressing (without the need for high temperatures and associated long cooling times) to release the valuable plant components.

CN105638935A describes a process to produce blueberry blend oil where the crude oil is heated to about 85 T, reacted with 0.2% phosphoric acid and mixed well for 30 minutes. This cold pressing method is used to maximise retention time of unsaturated acids, vitamins and other nutrients enhancing the nutritional value of cooking oil, which would be beneficial to human health.

CN1G3343046A describes the cold pressing of sesame cake at temperature between SOT to 70T with screw speed of 30-50, mixing cold-pressed sesame cake with water to form mixed solution, heat treating, adding 1-3% protease enzyme, performing enzymolysis at 45- 65 T for 0.5-2.5 hours with liquid ratio of 5-9 ml/g, performing alkaline extraction, centrifuging , breaking emulsion to obtain sesame oil, emulsion, extract, and residue, and demul sitying emulsion to obtain sesame oil and water phase which provides for a simple and safe process, mild reaction conditions, high extraction rate and low protein denaturation rate and reduces loss of nutrients .

Sue-Siang Teh et al . , (2012) (Physicochemical and quality characteristi cs of cold-pressed hemp, flax and canola seed oils) Journal of Food Composition and Analysis 30 (2013) 26-31 describes about cold-pressed seed oils containing bioactive compounds such as tocopherol, beta-carotene, chlophyll , phenolics and flavonoids that exert hea lth benefi ts . Col d-pressed hemp , fl ax and canola are healthy oi l s as they are ri ch i n unsaturated fatty acids name ly linolei accid , alpha-linolen acid (C18:3; n-3) and oleic aci d

(C18 : 1) respectively .

There remains a need in the art to provide a process to produce cold pressed palm fruit oil specifically cold pressed palm oil and cold pressed palm olein at low temperatures as opposed to conventional means which results in a cold pressed palm fruit oil preserved in natural antioxidants and bioactive compounds to address the above problems , or at least to provide an alternative.

SUMMARY OF THE INVENTION The present invention provides for process for producing cold pressed palm fruit oil with maintained natural antioxidant and bioactive compound contents to be substantially similar to prior to undergoing the process, the process including the steps of cleaning (2) palm fruits until all foreign objects such as trash and dirt are substantially removed , sterilizing (3) the palm fruits from step (a) at temperature of between ambient temperature to 60°C at atmospheric pressure for a time period of between 5 to 240 minutes to produce substantially sterilized palm fruits, digesting (4) the substantially sterilized palm fruits at temperature of between ambient temperature to 60'C at atmospheric pressure for a retention time period of between 5 minutes to 60 minutes to produce substantially digested palm fruits, pressing (5) the substantially digested palm fruits (5) at temperature of between ambient temperature to 60°C and at pressure of between 0 to 80 bar to produce the cold pressed palm fruit oil; and filtration (8) of the cold pressed palm fruit oil to remove gums such as phospholipids and phosphorus.

BRIEF DESCRIPTION OF THE DRAWING

Fig. 1 shows a general process flow for producing cold pressed palm fruit oil according to the preferred embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The purpose of this present invention is pertaining to a process of producing a new type of product mainly cold pressed palm oil or cold pressed palm olein with maintained natural antioxidant and bioactive compound contents to be substantially similar to prior to undergoing the process at the palm oil mill. Cold pressed palm oil traditionally maintains the natural nutrients of carotenes (precursors to Vitamin A) and the antioxidant tocotrienols (Vitamin E) . Cold pressed palm oil and cold pressed palm olein is also known as virgin palm oil and virgin palm olein. Crude palm oil naturally is very rich is plant pigments known as carotenoids which give the palm oil a natural orange-red colour. The carotenoids are removed in the conventional refining process, therefore, the purpose of this present invention is to retain these advantageous anti-oxidants and bioactive compounds in palm oil such asessential fatty acids, phenolics, flavonoids and tocopherol. These anti-oxidants and bioactive compounds are reported to play a vital role pertaining to boosting human's immune system, slowing down ageing of cells, promoting healthy growth of cells, preventing clogging at the arteries and protecting body from chronic illnesses.

The cold pressed palm oil of this present invention contains carotenoids about 500-1000 ppm and Vitamin E of more than 500 ppm comprising of 65% of tocotrienol s and 35% of alpha-tocopherols. The cold pressed palm olein of this present invention contains carotenoids of more than 600 ppm and Vitamin E of more than 500 ppm.

Cold pressed palm olein contains the highest known concentration of natural ly derived mixed-carotenes. It is the world’s richest natural plant sources of carotenes in term of retinol (Vitamin A) equivalent. Cold pressed palm olein is rich with Vitamin E (tocotrienols) which is a powerful natural antioxidant. It is effective in reducing the risk of stroke and heart related disease problems. Furthermore, vitamin E could reduce the formation of bad cholesterol and inhibiting of certain type of cancer. Cold pressed palm olein naturally contains unique phytonutrients, coenzyme QIG (CoQ10) , squalene and phytosterols that contributed to health benefits. In addition, these products are not genetically modified, KOSHER and HALAL certified. A single tablespoonful of cold pressed palm olein is enough to meet the body’s daily requirements of Vitamin A and Vitamin E.

Referring to Fig. 1, a process is provided for producing cold pressed palm fruit oil with maintained natural antioxidant and bioactive compound contents to be substantially similar to prior to undergoing the process.

The process firstly begins with the step of cleaning (2) the palm fruits (2) collected (1) from various sources to remove all foreign objects such as trash and dirt, foilowed by sterilizing (3) the palm fruits at temperature of between ambient temperature to 60°C at atmospheric pressure for a time period of between 5 to 240 minutes to produce sterilized palm fruits.

The sterilized palm fruits then goes through a digestion step (4) at temperature of between ambient temperature to 60 °C at atmospheric pressure for a retention time period of between 5 to 60 minutes to produce digested palm fruits Preferably, the digestion step (4) of the sterilised fruits is for a time frame of between 15 to 25 minutes.

Next is the pressing (5) of the digested palm fruits at temperature of between ambient temperature to 60°C at a pressure range of between 0 to 80 bar, preferably 40 to 75 bar and most preferably 40 to 70 bar conducted continuously to produce the cold pressed palm fruit oil. The cold pressed palm fruit oil is then centrifuged at 3,500 rpm for 3 to 5 minutes to separate cold pressed palm fruit oil from sludge. In a larger scale, the cold pressed palm fruit oil is centrifuged at 1,400-1,800 rpm or passed through a 2-phase decanter at 2,500-3,500 rpm to separate cold pressed palm fruit oil from sludge.

The pressing (5) of the palm fruits can be done using a screw press , hydraulic press , hand press or filter press where these pressing means are able to be conducted at temperature of between ambient temperature to 60°C. This temperature range is an optimum range to produce cold pressed palm oil, so that the oil produced is enriched with natural antioxidant properties . The pressing of these palm fruits produces cold pressed palm oil.

Once the pressing (5) is completed, a 2-phase decanter or centrifuge is used in a centrifuging step (6) to separate cold pressed palm oil from sludge . The term “sludge” used herein may encompass separator sludge, sterilizer condensate and palm oil mill effluent.

The cold pressed palm is further purified and dried (?) to remove foreign objects such as dirt and moisture. The purification step (7) is to further remove dirt from the cold pressed palm oil and can be done via a purifier machine installed at the palm oil mills to ensure dirt value is below 0.02%. The drying step (7) to remove further moisture content and can be done via a vacuum dryer or rotatory evaporator to ensure the moisture content is below 0.15%. The said cold pressed palm oil then proceeds to the filtration step (8) utilising membrane filtration to remove contaminants such as phospholipids, phosphorus and chlorinated compounds whereby the membrane filtration that is conducted here is with or without the use of phosphoric acid or citric acid. The membrane used herein are. ceramic membrane, polymeric membrane, polyvinylidene fluoride (PVDF) membrane, multi -channel tubular Zirconia/a-Alumina ceramic membrane or any combination thereof. The cold pressed palm oil is then further fractionated (8) to produce a cold pressed palm olein.

The cold pressed palm oil produced via this process contains has free fatty acids (FFA) content between 0% to 4%, Deterioration of Blieachability Index (DOBI) value between 2.3 to 5.0, volatile matter (VM) value between 0 - 0.15%, value for dirt between 0 - 0.02%, peroxide value (PV) value between 0 - 3.0 meq/kg, carotene content between 500 to 1000 ppm and iodine value (IV) value between 50.0 to 55.0.

The cold pressed palm olein produced via this process has free fatty acids (FFA) content of between 0 to 4%, Deterioration of Bleachability Index (DOBI) value between 2.3 to 5, volatile matter (VM) value between 0 to 0.15%, value for dirt between 0 to 0.02%, peroxide value (PV) value between 0 to 3 meq/kg, carotene content between more than 600 ppm and iodine value (IV) value between more than 56. The cold pressed palm oil and cold pressed palm olein is stored at a temperature of between ambient temperature to 60°C. Preferably, the cold pressed palm oil and cold pressed palm olein is stored at room temperature,

The scope of the present invention is not limited to the disclosure in the detailed description of the preferred embodiments but only by the scope of the appended claims. The following examples are provided to further illustrate and describe particular embodiments of the present invention, and are in no way to be construed to limit the invention to the specific procedures , conditions or compositions described therein. EXAMPLES

Example 1

Quality of cold pressed palm oil is dependent on the quality of palm fruits collected from different sources. The results of the cold pressed palm oil quality from the trial as compared with standard crude palm oil (CPO) are shown in Table 1 as follows; -

Table 1

The results above shows the comparison between cold pressed palm oil and standard CPO. It shows the cold pressed palm oil gives superior results in terms of FFA (%) level, DOBI and Carotene Value.

Example 2 Sample of cold pressed palm oil have been subjected to a fractionation process, which is then compared with standard olein. The results are shown in Table 2 as follows:

Table 2 The results above show the comparison between crude cold pressed palm olein and standard olein. It shows that between crude cold pressed palm olein gives superior results in terms of FFA (%) level, D08I and Carotene Value.

Claims

1. A process for producing cold pressed palm fruit oil with maintained natural antioxidant and bioactive compound contents to be substantially similar to prior to undergoing the process, the process including the steps of: a. cleaning (2) palm fruits until all foreign objects such as trash and dirt are substantially removed; b. sterilizing (3) the palm fruits from step (a) at temperature of between ambient temperature to 60°C at atmospheric pressure for a time period of between 5 to 240 minutes to produce substantially sterilized palm fruits; c. digesting (4) the substantially sterilized palm fruits at temperature of between ambient temperature to 60 °C at atmospheric pressure, for a retention time period of between 5 minutes to 60 minutes to produce substantially digested palm fruits; d. pressing (5) the substantially digested palm fruits at temperature of between ambient temperature to 60°C and at pressure of between 0 to 80 bar to produce the cold pressed palm fruit oil; and e. filtration (8) of the cold pressed palm fruit oil to remove gums such as phospholipids and phosphorus.

2. The. process according to Claim 1, wherein the palm fruits are pressed using screw press, hydraulic press, hand press, filter press or any combination thereof.

3. The process according to Claim 2, wherein a 2-phase decanter or centrifuge is used in a centrifugation step (6) to separate the cold pressed palm fruit oil from sludge.

4. The process according to Claim 3, wherein the cold pressed palm fruit oil undergoes purification and drying (7) so that foreign objects such as dirt and moisture are substantially removed .

5. The process according to Claim 1, wherein the filtration (8) of step (e) entails the cold pressed palm fruit oil being passed through a membrane such as a filtration membrane or ultrafiltration membrane to remove gums such as phospholipids and phosphorus.

6. The process according to Claim 5, wherein the ultrafiltration membrane used is selected from a ceramic membrane, polymeric membrane, polyvinylidene fluoride (PVDF) membrane, multi-channel tubular Zirconia/a-Alumina ceramic membrane or any combination thereof.

7. The process according to Claim 1, wherein the cold pressed palm fruit oil is a cold pressed palm oil.

8. The process according to Claim 7, wherein the cold pressed palm oil is further fractionated (9) to produce a cold pressed palm olein.

9. The process according to Claim 7, wherein the cold pressed palm oil has free fatty acids (FFA) content between 0% to 4%, Deterioration of Bleachability Index (DOBI) value between 2.3 to 5.0, volatile matter (VM) value between 0 - 0.15%, value for dirt between 0 - 0.02%, peroxide value (PV) value between 0 - 3.0 meq/kg , carotene content between 500 to 1000 ppm and iodine value (IV) value between 50.0 to 55.0.

10. The process according to Claim 8, wherein the cold pressed palm olein has free fatty acids (FFA) content of between 0 to 4%, Deterioration of Bleachability Index (D0BI) value between 2.3 to 5.0, volatile matter (VM) value between 0 to 0.15%, value for dirt between 0 to 0.02%, peroxide value (PV) value between 0 - 3.0 meq/kg, carotene content more than 600 ppm and iodine value (IV) value more than 56.

11. The process according to Claim 1, wherein the process further includes a step wherein the cold pressed palm fruit oil is stored at a temperature of between ambient temperature to 60^"C.