Process to prepare a vegetable oil comprising one or more carotenoid pigments and food composition comprising it

Abstract

The invention is directed to a process to prepare a vegetable oil comprising one or more carotenoid pigments by contacting the vegetable oil with a powder of the flavedo of a citrus fruit, such as a citrus sinensis, wherein the one or more carotenoid pigments are extracted from the powder of the flavedo of the citrus sinensis by the vegetable oil. The powder may comprise for more than 90 wt% of particles having a diameter smaller than 200 um and having a water content of less than 10 wt%.

Description

[0001] PROCESS TO PREPARE A VEGETABLE OIL COMPRISING ONE OR MORE CAROTENOID PIGMENTS AND FOOD

[0002] COMPOSITION COMPRISING IT

[0003] The invention is directed to a process to prepare a vegetable oil comprising one or more carotenoid pigments.

[0004] US4497838 describes how pulverized peel is contacted with methanol. Carotenoid pigments are extracted into the methanol phase. After isolating an oil phase solid carotenoid pigments are recovered by distillation of the oil phase

[0005] US4377520 describes a process to isolate carotenoid pigments from orange peel by abrading the flavedo from a citrus fruit to obtain a mash of flavedo, peel oil and water. Contacting the mash with a dehydrating salt, such as anhydrous sodium sulphate, and separating an oil and water fraction. The oil fraction contains high amounts of carotenoid pigments.

[0006] DE2525590 describes a process where dried orange peel is crushed and extracted three times with hexane. The extract is separated with a filter. The hexane solvent is separated by evaporation to obtain an oil containing about 15 g carotenoid per kg oil. Solid carotenoid pigments are obtained from this oil having a high purity.

[0007] LIS20140030419 describes a process to prepare a vegetable oil comprising carotenoid pigments, such as xanthophyll. In this process xanthophyll crystals are first dissolved in dichloromethane and the resulting solution is sprayed onto a stirred soybean oil under vacuum. The dichloromethane evaporated and the xanthophyll dissolves in the soybean oil.

[0008] EDINSON YARA-VARON-ET AL: "Vegetable oils as alternative solvents for green oleo-extraction, purification and formulation of food and natural products", MOLECULES, vol. 22, nr. 9, 5 September 2017 (2017-09-05), page 1474, XP055551896,DOI: 10.3390 / molecules22091474 describe the relevancy of vegetable oils as solvents. ORDONEZ-SANTOS LUIS EDUARDO ET AL: "Ultrasound-assisted extraction of total carotenoids from mandarin epicarp and application as natural colourant in bakery products", LWT- FOOD SCIENCE AND TECHNOLOGY, vol. 139, 21 November 2020 (2020-11 -21 ), XP086470882, ISSN: 0023-6438, DOI:

[0009] 10.1016 / J.LWT.2020.110598 describes a process where the flavedo of a mandarin is manually obtained by cutting very thin julienne slices. From these slices a powder of the flavedo is made and mixed with sunflower at a ratio of between 0.0004 and 0.0012 gram powder per ml of sunflower oil to obtain an oil having a carotene content of about at most 2 mg / kg oil.

[0010] The prior art describes a route to a vegetable oil comprising one or more carotenoid pigments wherein first the carotenoid pigments are isolated from a biomass source and subsequently added to a vegetable oil. The above processes to isolate a carotenoid pigment involve the use of a solvent which is separated by evaporation. US20140030419 also shows a process which makes use of a solvent which is separated by vacuum evaporation. The use of solvents and the multiple steps to obtain the vegetable oil comprising one or more carotenoid pigments makes the process route complex. The process described by ORDONEZ-SANTOS LUIS EDUARDO ET AL is directed to mandarins. It is less complex but results in oils having a very low content of carotenoid pigments. The object of the present invention is to provide a less complex process to prepare vegetable oil comprising a higher content of one or more carotenoid pigments.

[0011] This object is achieved by the following process. A process to prepare a vegetable oil comprising one or more carotenoid pigments by contacting the vegetable oil with a powder of the flavedo of a citrus sinensis wherein the one or more carotenoid pigments are extracted from the powder of the flavedo of the citrus sinensis by the vegetable oil, wherein the water content of the powder of the flavedo of the citrus sinensis is less than 10 wt% and wherein the mass ratio between the powder of the flavedo of the citrus sinensis and the vegetable oil is between 1 : 10 and 20 : 10..

[0012] Applicants found that the carotenoid pigments as present in the flavedo of a citrus sinensis can be effectively and directly extracted into the vegetable oil when a dried powder of the flavedo is used in the claimed process. More advantages will be discussed below when discussing preferred embodiments of the invention.

[0013] The citrus sinensis is also known as sweet orange.

[0014] The carotenoid pigment may be any one of [3-carotene, antheraxanthin, mutatoxanthin, loroxanthin, neoxanthin, violaxanthin, neochrome, luteoxanthin, auroxanthin, a-cryptoxanthin, [3-cryptoxanthin, lutein and zeaxanthin and more specific one or more of violaxanthin, [3-cryptoxanthin and [3-carotene.

[0015] The vegetable oil is one of sunflower oil, high oleic sunflower oil, rapeseed oil, soybean oil, palm oil, palm stearin, palm olein, palm superolein, linseed oil, olive oil, coconut oil, cottonseed oil, rice bran oil, peanut oil and mixtures thereof. A preferred vegetable oil is sunflower oil. Sunflower oil is preferred because the carotenoid pigments easily augment the naturally occurring light yellow colour of the sunflower oil.

[0016] In this specification reference shall be made to the flavedo and albedo of a citrus sinensis. The flavedo is the outer side part of the peel of the citrus sinensis. The albedo is the fibrous inner side of the citrus sinensis peel. Within the citrus sinensis juice vesicles are present which carry the citrus juice. Juice vesicles facing the albedo are connected to the albedo. This is also explained in htps: / / en.wikipedia.org / wiki / Fruit anatomy.

[0017] The powder of the flavedo of a citrus sinensis may be obtained by separating the flavedo from a citrus sinensis peel, drying the thus obtained flavedo and milling or grinding the flavedo to a powder.

[0018] Separating the flavedo from the citrus sinensis peel may be by abrading the flavedo from a citrus sinensis as described in the above cited prior art documents. In a preferred embodiment the flavedo is separated from a citrus peel. The citrus sinensis peel is obtained from the citrus sinensis by separating the majority of the juice vesicles from the peel. The citrus sinensis peel is preferably a so-called citrus peel halve. The citrus halves are preferably obtained in a process where the citrus sinensis is halved and from which halves juice has been partly removed. Such processes are well known for domestic use and in retail. For example citrus juicing machines as present in retail, bars and restaurants extract juice from citrus sinensis halves as described in for example WO 2004 / 052126, US5170699, US2007074630. The citrus peel halves obtained after extracting the juice are suitably used as the starting citrus peel halves for obtaining the flavedo powder.

[0019] The citrus peel halves are preferably collected at retail, for example super markets, bars and restaurants. Preferably any contaminants, such as plastic bottle caps, are removed from the collected citrus halves. The collected citrus halves preferably comprise of juice vesicles which are not removed when the juice is extracted at such retail locations.

[0020] The flavedo is preferably separated from the albedo by cutting the citrus peel and preferably the citrus peel halves. By cutting the peel a part enriched in flavedo and a part enriched in albedo is obtained. Cutting may be performed by pressing a citrus halve, which is positioned belly up and cutting the top part from a remaining lower part. The top part is the part enriched in flavedo. The part enriched in flavedo is between 20 and 50 wt% of the starting citrus halve. When the citrus peel halve comprises juice vesicles it is preferred to cut the peel such that more than 90 wt% of the juice vesicles of the starting citrus peel halve is present in part enriched in albedo. The resulting powder of the flavedo will comprise of substantially the flavedo of the citrus sinensis but may, as a result of the cutting of the citrus peel, also comprise of some albedo and even some of the juice vesicles. The content of flavedo in the powder of the flavedo may be above 40 wt% and preferably above 60 wt%.

[0021] To effectively cut the peel it is preferred that the peel has not been subjected to a mechanical oil extraction because the citrus sinensis peel would then not have enough mechanical strength to be cut. Drying of the flavedo may be performed by a conveyor dryer, rotary dryer, fluidized bed dryer, microwave dryer, steam-tube dryer or batch tray dryer. Drying and milling is performed such to obtain a powder of the flavedo of the citrus sinensis having a water content of less than 20 wt% and preferably less than 10 wt%.

[0022] Milling and grinding may be performed by any means, such as for example by a roll crusher, shredder, ball mill, hammer mill, roll mill and preferably by means of a rotary cutter and / or dicer. The powder of the dried flavedo is suitably comprised for more than 90 wt%, preferably more than 95 wt% of particles having a diameter smaller than 200 pm. Preferably less than 10 wt% have a diameter of below 50 pm.

[0023] The temperature at which the carotenoid pigments are extracted is suitably between 10 and 70 °C and preferably between 25 and 55 °C.

[0024] The mass ratio between the powder of the flavedo of a citrus sinensis and the vegetable oil is suitably between 2 : 10 and 20 : 10 and preferably between 4 : 10 and 8 :10. The maximum amount of powder which can be contacted with a certain volume of vegetable oil is determined by the resulting viscosity of the suspension. At a certain high viscosity it is not possible to mix the powder and the oil effectively such that extraction takes place. This ratio is per contacting step, wherein a contacting step involves contacting and separation of the remaining powder from the vegetable oil comprising one or more carotenoid pigments.

[0025] The contacting is preferably performed in a batch process or a semi-batch process wherein the powder of the flavedo and / or the vegetable oil is added to a batch reactor during the extraction. The contact time or average contact time between the powder of the flavedo and the vegetable oil is preferably between 30 and 120 minutes.

[0026] After the extraction the remaining powder of the flavedo is separated from the vegetable oil comprising one or more carotenoid pigments. Such a separation may be performed by well known separation techniques, such as by filtration, sedimentation and / or by applying a centrifugal force. Preferably the vegetable oil is contacted with the powder of the flavedo in at least two steps. In this way it is possible to contact a volume of vegetable oil with more powder of the flavedo without having the high viscosity issues as described above. In a first step an intermediate vegetable oil comprising one or more carotenoid pigments comprising one or more carotenoid is obtained by the extraction with a first part of the powder of the flavedo. After separating all or part of the first part of the powder of the flavedo the intermediate vegetable oil comprising one or more carotenoid pigments is contacted with a second part of the powder of the flavedo. In this next extraction step the one or more carotenoid pigments are extracted from the second part of the powder of the flavedo of the citrus sinensis by the intermediate vegetable oil obtain a vegetable oil having a higher content of carotenoid pigments than the content of carotenoid pigments in the intermediate vegetable oil. It has been found that such a process involving two extraction steps may yield a vegetable oil having a sufficient high content of carotenoid pigments. Preferably oils having a content of between 100 and 3000 mg carotenoid pigments per kg vegetable oil may be obtained. Nevertheless the next step may optionally be repeated to further increase the content of carotenoid pigments in the vegetable oil.

[0027] After a single or multiple extractions steps a vegetable oil may be obtained which also contains other compounds extracted from the powder of the flavedo. Such compounds may be d-limonene, myrcene, ethyl hexanoate, alpha pinene, linalool, sabine, decanal or octanal. It may be preferred to remove any one or more of these compounds from the vegetable oil. Preferably d-limonene is removed from the vegetable oil. D-limonene may be removed by vacuum distillation, short path distillation or steam stripping at ambient or reduced pressure or combinations of such processes. Preferably d-limonene is removed by a process called deodorization, wherein the oil is brought into contact with steam at a pressure below 100 mbar and preferably below 50 mbar and at a temperature of between 140 and 260 °C, preferably between 160 and 200 °C. Contact times may vary between 15 minutes and several hours.

[0028] The vegetable oil comprising one or more carotenoid pigments may be used as ingredient in a food composition. Examples of suitable food compositions comprising this vegetable oil are chosen from the group consisting of margarin, products containing oils and fats as the main ingredient, sweet and savoury fat based fillings, bakery products, spreads, meat and fish replacers and dairy products.

[0029] The vegetable oil comprising one or more carotenoid pigments is especially used to replace fat in a food composition and more especially wherein the food composition is any one listed above. Preferably at least 10 wt% and more preferably at least 20 wt% of said fat is substituted by the oil extract. All fat may be replaced by the obtained vegetable oil comprising one or more carotenoid pigments. Preferably the food product has a weight ratio of triglyceride of the vegetable oil to other triglycerides of more than 4 :1 and preferably more than 9 :1 and up to a food product having only triglycerides of the vegetable oil.

[0030] Example 1

[0031] A powder of a flavedo was obtained by pressing a citrus halve of a sweet orange, which is positioned belly up and cutting the top part from a remaining lower part. The citrus halve was the peel as obtained in a process to extract the juice in a citrus juicing machine. The top part is the part enriched in flavedo. The part enriched in flavedo was about 30 wt% of the starting citrus halve. More than 95 wt% of the juice vesicles of the starting citrus sinensis peel halve were present in the part enriched in albedo. The part rich in flavedo was dried overnight in 50 °C hot air and ground using a Vitamix High Performance Blender to obtain a powder having a particle size of below 0.25 mm for more than 90 wt% of the powder. The content of flavedo in the powder of the flavedo was 70 wt%.

[0032] The powder was contacted with sunflower oil at 50 °C for 1 hour while stirring at a powder to oil weight ratio of 0.6 : 1 . After one hour the powder was removed by a centrifugal separation. The sunflower oil had a [3-carotene equivalent (BCE) concentration of 515 mg / kg. This concentration was measured using the following procedure. The obtained oil was analysed using a Hitachi U-1900 Spectrophotometer. A wavelength scan was done between 300 and 600 nm at a scan speed of 100 nm / min and sampling interval of 0.5 nm. The oil sample was placed in a cuvettes made from poly(methyl methacrylate) and having a 1 cm transmission length. A baseline was measured using pure isopropanol. Samples were diluted in isopropanol prior to measurement. A calibration curve was made using a sunflower oil containing a known amount of [3-carotene. The absorption at 425 nm was used to determine the concentration of the total mix of carotenoids in the product, when compared to the known [3-carotene content as determined by the calibration curve. This measured concentration is referred to as ‘[3-carotene equivalent’ or BCE

[0033] Example 2

[0034] Example 1 was repeated except that the milling was performed to obtain a powder having a particle size of above 0.25 mm for more than 90 wt% of the powder. The sunflower oil had a [3-carotene equivalent (BCE) concentration of 330 mg / kg.

[0035] Example 3

[0036] Example 1 was repeated for a contact time to obtain an intermediate sunflower oil having a beta carotenoid pigment content of 400 mg / kg. This intermediate oil was contacted with fresh powder oil at 50 °C for 1 .5 hour while stirring at a powder to oil weight ratio of 0.6 : 1. After 1.5 hour the powder was removed by a centrifugal separation. The sunflower oil had a [3-carotene equivalent (BCE) concentration of 1000 mg / kg.

[0037] Comparative experiment A

[0038] To show the effect of drying, a set of comparison experiments was carried out where the flavedo of a citrus sinensis was mechanically reduced to a wet paste by colloid milling followed by high pressure homogenization. The dry matter content of the flavedo paste was determined to be 10 weight percent. The paste to oil ratio was adjusted in order to achieve similar extraction ratios as for dried flavedo powder. The [3-carotene equivalent (BCE) concentration of resulting oils was analysed and listed in Table 1 as experiment A1 .

[0039] As it was observed that the mechanically reduced flavedo paste did not mix well with the sunflower oil, small amounts of pectinase (Experiment A2) and cellulase (Experiment A2) were added to smooth the paste even further. This did not significantly improve the final carotenoid concentration in the oil. Table 1

[0040] Example 1 and Comparative Experiment A1 were repeated except at different powder (or dry weight) to oil ratio’s. The resulting carotenoid concentration in the oil is presented in Figure 1 wherein line A is according to Example 1 and line B is according Experiment A1 .

[0041] Example 4

[0042] 332 gram of sunflower oil obtained in Example 1 , referred to as the untreated oil, and 85 grams of demineralized water were put in a 1000 ml round bottom flask. The flask was fitted to a BUCHI Rotavapor R-200 / 205, pressure set at 100 mbar and temperature of the oil bath kept at approximately 80 °C. The flask rotated at 50 rpm and the experiment lasted for an hour. Such a laboratory experiment simulates a steam treatment at the same temperature and pressure. After most of the water had been removed by evaporation the flask was removed and allowed to cool. The resultant oil / water emulsion was poured into a separatory funnel and allowed to separate after which the water was drained. The combined water fractions had a citrus-like smell and were shown to contain 0.074 weight percent d-limonene. The colour of the recovered oil, ie the treated oil, had not been negatively impacted by the treatment. A panel consisting of eleven people was asked to score the citrus smell of the untreated and treated oils on a 1 to 5 hedonistic scale, where 1 = no or low citrus smell and 5 = high citrus smell. Citrus smell is a measure of the d- limonene content in the oil. The treated oil scored significantly better in terms of citrus smell while the colour remained the same as the untreated oil. This shows that a vegetable oil comprising carotenoid pigments can be obtained starting from citrus sinensis which oil is substantially free of d-limonene.

[0043] Table 2:

[0044] Example 5

[0045] Example 1 was repeated with another batch of citrus sinensis peels; part of which were cut to obtain a part enriched in flavedo. This part was 30 wt% of the starting citrus sinensis halve. From the part enriched in flavedo a powder referred to as ‘flavedo powder’ was obtained. From the citrus sinensis peel which was not cut a powder referred to as ‘whole peel powder’ was obtained.

[0046] The sunflower oil based on the flavedo powder had a [3-carotene equivalent (BCE) concentration of 390 mg / kg, the sunflower oil based on the whole peel powder had a [3-carotene equivalent (BCE) concentration of 255 mg / kg. This shows that a higher content oil can be obtained when starting from a powder made from a part enriched in flavedo.

Claims

CLAIMS A process to prepare a vegetable oil comprising one or more carotenoid pigments by contacting the vegetable oil with a powder of the flavedo of a citrus sinensis wherein the one or more carotenoid pigments are extracted from the powder of the flavedo of the citrus sinensis by the vegetable oil, wherein the water content of the powder of the flavedo of the citrus sinensis is less than 20 wt% and wherein the mass ratio between the powder of the flavedo of the citrus sinensis and the vegetable oil is between 1 : 10 and 20 :

10. A process according to claim 1 , wherein the powder is comprised for more than 90 wt% of particles having a diameter smaller than 200 pm. A process according to any one of claims 1 -2, wherein the water content of the powder of the flavedo of the citrus sinensis is less than 10 wt%. A process according to any one of claims 1 -3, wherein the temperature at which the carotenoid pigments are extracted is between 10 and 70 °C. A process according to claim 4, wherein the temperature is between 25 and 55 °C. A process according to any one of claims 1-5, wherein the mass ratio between the powder of the flavedo of a citrus fruit and the vegetable oil is between4 : 10 and 8 :

10. A process according to any one of claims 1 -6, wherein the one or more carotenoid pigments comprises violaxanthin, [3-cryptoxanthin and / or [3- carotene.

8. A process according to any one of claims 1-7, wherein the vegetable oil is one of sunflower oil, high oleic sunflower oil, rapeseed oil, soybean oil, palm oil, palm stearin, palm olein, palm superolein, linseed oil, olive oil, coconut oil, cottonseed oil, peanut oil.

9. A process according to claim 8, wherein the vegetable oil is sunflower oil.

10. A process according to any one of claims 1 -9, wherein d-limonene extracted from the powder of the flavedo into the vegetable oil is removed.

11. A process according to claim 10, wherein the removal of d-limonene is performed by contacting the vegetable oil comprising one or more carotenoid pigments with low pressure steam.

12. A process according to any one of claims 1-11 , wherein the powder of the flavedo is separated from the vegetable oil comprising one or more carotenoid pigments by filtration, sedimentation and / or by applying a centrifugal force.

13. A process according to claim 12, wherein the vegetable oil is contacted with the powder of the flavedo in at least two steps, wherein in a first step an intermediate vegetable oil comprising one or more carotenoid pigments comprising one or more carotenoid is obtained by the extraction with a first part of the powder of the flavedo and wherein after separating all or part of the first part of the powder of the flavedo the intermediate vegetable oil comprising one or more carotenoid pigments is contacted with a second part of the powder of the flavedo wherein the one or more carotenoid pigments are extracted from the second part of the powder of the flavedo of the citrus sinensis by the intermediate vegetable oil obtain a vegetable oil having a higher content of carotenoid pigments than the content of carotenoid pigments in the intermediate vegetable oil.

14. A process to prepare a vegetable oil comprising one or more carotenoid pigments from a citrus sinensis peel comprising of flavedo and albedo andseparating the flavedo from the albedo, drying the flavedo to obtain a dried flavedo and milling the dried flavedo to a powder of the flavedo and contacting the vegetable oil with the powder of the flavedo according to the process of any one of claims 1 -13. A process according to claim 14, wherein the citrus sinensis peel is a citrus sinensis halve which is cut in a part enriched in flavedo and a part enriched in albedo and wherein the part enriched in flavedo is dried and milled to obtain the powder of the flavedo. A process according to claim 15, wherein the part enriched in flavedo is between 20 and 50 wt% of the starting citrus sinensis halve. A process according to any one of claims 15-16, wherein the citrus sinensis halves comprise juice vesicles and wherein more than 90 wt% of the juice vesicles of the starting citrus sinensis halve is present in part enriched in albedo. A food composition comprising a vegetable oil comprising one or more carotenoid pigments as obtained from a process according to any one of claims 1-17, wherein said food composition is chosen from the group consisting of margarin, products containing oils and fats as the main ingredient, sweet and savoury fat based fillings, bakery products, spreads, meat and fish replacers, dairy products The product of claim 18, wherein the weight ratio of triglyceride of the vegetable oil to other triglycerides is more than 4:1 .

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