MXPA98010372A - Antioxide extraction - Google Patents

Abstract

The invention relates to a process for the extraction of antioxidants from olives, a lipid fraction enriched with antioxidants, an extract enriched with antioxidants as well as a conset or food composition comprising this extrac

Description

ANTIOXIDANT EXTRACTION DESCRIPTION OF THE INVENTION The subject of interest of the present invention is a process for the extraction of antioxidants from olives or olives, a lipid fraction enriched with antioxidants, an extract enriched with antioxidants, as well as a food or cosmetic composition containing this lipid fraction or this extract. In a conventional process, the olives are treated by pressing them and three phases are obtained: an aqueous phase, a lipid phase and a solid phase. In such a process, the aqueous phase and the solid phase are removed. The water-soluble antioxidants are thus lost in the solid phase and also in the aqueous phase. In addition, these antioxidants are so diluted in the aqueous phase that even if desired, they could no longer be recovered. In addition, the aqueous phase, whose volume is approximately four times greater than the volume of the lipid phase, has to be treated as waste water in a wastewater treatment plant.

Thus, A. Uzzan (Manuel des corps gras - ISBN 2 - 85206 - 662/9 - 1992 - 763 - 768) describes in particular a process for the production of olive oil by pressing, in which the olives or Olives are cleaned, worked and then passed through a hydraulic press to separate the liquid phase from the solid phase. In this stage, the liquid phase is divided by decanting or by centrifugation in its two constituents: the aqueous phase that contains the water-soluble substances in the olive, and the olive oil. These two constituents are once again centrifuged to, on the one hand, collect the clarified and purified oil and, on the other hand, extract the residual oil contained in the aqueous phase. This aqueous phase, as well as the previous solid phase, which are still rich in antioxidants, are removed. The objective of the present invention is to propose a process which makes it possible to recover, from green olives and / or from ripe olives, that is to say at different degrees of maturity, on the one hand, a lipid fraction enriched with antioxidant and, on the other hand, an extract enriched with antioxidants.

For this, in the process for the extraction of antioxidants from the olives according to the invention: the olives are ground, - these ground olives are dried in a vacuum to obtain dried olives rich in water-soluble antioxidants, these dried olives are pressed to recover a lipid fraction enriched with antioxidants and an oil cake, at least one extraction is carried out on the oil cake at high temperature with MCT, that is to say a mixture of medium chain triglycerides, or with an alkylene glycol of 2 to 6. carbon atoms using a pressure greater than or equal to 40 bars, and then "an extract enriched with antioxidants is recovered from the oil cake." It has surprisingly been observed that such a process makes it possible to obtain a lipid fraction and an extract enriched with antioxidants and, more particularly, with water-soluble antioxidants, in addition, taking into account the fact that water exists and waste, the process according to the present invention has obvious ecological advantages.

The olives can be chosen for example from green olives and / or ripe olives. The olives can be, for example, frozen to facilitate grinding. The olives are therefore crushed.

To do this, the usual techniques are used for grinding or crushing stone fruits, especially hammer, disc, colloidal or molasses grinds or a knife cutter. Ground or crushed olives can be treated enzymatically with the help of enzymes of bacterial or fungal origin, by means of hydrolases, glycosylases or polyphenolhydrolases, for example, to hydrolyse the glycosides and improve the extraction of antioxidants, for example. The crushed olives can be dried under vacuum at a temperature less than or equal to 80 ° C, to recover dried olives rich in water-soluble antioxidants, and whose water content is 1-20% by weight, for example. Preferably, the drying is performed to obtain dried olives whose water content is 5-10% by weight. In this way, only the formation of two phases, the lipid fraction enriched with antioxidants and the oil cake, is favored during the pressing step.

It is possible to lyophilize at a reduced pressure of 10 ~ 3 - 10 1 bar or in an oven at a reduced pressure of 0.1 to 0.2 bar, for example. The dried olives can be preheated and maintained at a high temperature for a certain period of time, before carrying out the pressing, to increase the antioxidant content of the lipid fraction. These dried olives are therefore pressed to recover a lipid fraction enriched with antioxidants and an oil cake. This pressing can be carried out at room temperature or at an elevated temperature in a piston press equipped with a filtration cage, especially a Carver type press marketed by the company Fred S. Carver, Menomonee Falls, Wisconsin - USA, for pressing and filter in a single step. Subsequently, at least one extraction is carried out on the oil cake at high temperature with the MCT or with alkylene glycol of 2 to 6 carbon atoms, using a pressure greater than or equal to 40 bar. At least one extraction can be carried out on the oil cake in an MCT or the weight ratio of the alkylene glycol cake of 2 to 6 carbon atoms / oil of 0.5 to 2, for example. This or these high temperature extractions can be performed in a piston press equipped with a Carver type filtration cage. The alkylene glycol can be, for example, glycol, 1,2-propylene glycol or 1,3-butylene glycol. During a high-temperature extraction with MCT by pressing, the fat-soluble antioxidants are mainly isolated and during a high-temperature extraction with alkylene glycol of 2 to 6 carbon atoms by pressing, the fat-soluble antioxidants are isolated and the antioxidants soluble in water. The present invention also relates to a lipid fraction enriched with antioxidants whose induction time is 15-75 h at a temperature of 110-120 ° C. In addition, the present invention relates to an extract enriched with antioxidants, which is capable of being obtained using said process. This extract comprises water-soluble antioxidants, especially hydroxytyrosol, tyrosol, phenolic acids and oleuropein. The present invention relates to a food or cosmetic composition containing 0.5 to 4% of extract enriched with antioxidants, which is obtained using the process according to the present invention. Finally, the present invention relates to a food or cosmetic composition comprising a lipid fraction enriched with antioxidants, which is obtained using the process according to the present invention. The process according to the present invention is described in greater detail in the following non-limiting examples. In these examples, the percentages will be by weight, unless indicated otherwise.

Example 1 1 kg of frozen green olives whose total water content of 55% by weight is crushed using the Alpina crusher, marketed by C. Hoegger and Cié AG, Gossau, CH - St Gall. These crushed green olives are dried in a vacuum oven of the Inox Maurer 20 type, marketed by the company Maurer AG, Trimbach, CH - Soleure, at a temperature of 55 ° C and a reduced pressure of 0.1 bar, to obtain dried green olives. whose total water content is 6% by weight.

Next, these dried green olives are pressed at room temperature in a Carver type piston press, at 500 bars for 60 minutes, to recover the lipid fraction enriched with the antioxidants and the oil cake. Then, 50 g of the oil cake recovered in this way at high temperature with 1,2-propylene glycol are extracted. To do this, 50 g of 1,2-propylene glycol are added to the 50 g of the oil cake. The The whole is left under stirring for 60 minutes at 80 ° C and the mixture is pressed on a Carver type piston press at 500 bar for 60 minutes. The extract enriched with antioxidant is thus recovered. The Rancimat® test at 110 ° C, in various fats and oils, gives the antioxidant power in the form of antioxidant values indicated in the Table 1 later The antioxidant value is defined as the ratio: induction time (example: extract + 20 oil) / induction time (oil).

Rancimat® oxidation test at 110 ° C: The mixture was covered with a closed reactor.

The mixture is heated to 110 ° C and saturated with oxygen derived from air introduced to the reactor. During oxidation, the reactor itself is connected via a flexible tube to a vessel containing distilled water, and into which a platinum electrode is immersed. Volatile compounds cause an increase in conductivity. The conductivity is measured and the induction periods are calculated. The induction time is calculated graphically from the plotted curve of the conductivity as a function of time, by intersecting the tangent to the curve with the time axis.

Comparative Example 1 A procedure is carried out as described in Example 1, except for the fact that 50 g of the recovered oil cake are extracted at high temperature by the organic route, with 85% ethanol. To do this, add 100 ml of ethanol to the 85% at 50 g of the oil cake. The whole is left stirring for 60 minutes at 80 ° C and filtered, before being concentrated to 50% of the volume. Then, 50 g of propylene glycol are added, the ethanol is evaporated and the residue is centrifuged for 10 minutes at 3000 rpm, to clarify it. An extract containing the antioxidants is recovered. The Rancimat® test at 110 ° C in various fats and oils gives the antioxidant power in the form of antioxidant values indicated in Table I below.

Table I For the Rancimat test, measurements are carried out in the presence of 2% extract in relation to chicken fat or in relation to olive oil.

The measurement of antioxidant power, indicated in the form of the antioxidant value, in Table I, shows the quality and oxidative stability of the extract obtained using the process according to the present invention (Example 1). This quality and this oxidative stability are comparable to those obtained by an extract obtained using a more complex process, in which a high temperature extraction is carried out by the organic route (Example i).

Example 2 The procedure is carried out in the manner described in Example 1, except for the fact that the measurements for the Rancimat® test are carried out in the presence of 1% extract relative to the chicken fat or in relation to the olive oil. In addition, the antioxidant power is measured in the form of an antioxidant value by the oxygen electrode method at 30 ° C in corn oil. These measurements are carried out in the presence of 1% extract in relation to corn oil. In addition, the induction time for the lipid fraction recovered after pressing, from green olives dried at room temperature, is measured by the Rancimat® test at 120 ° C. The value of the induction time for the lipid fraction is described in Table III below.

Oxidation test: oxygen electrode at 30 ° C An emulsion is prepared by mixing 5% oil and the indicated percentage of the antioxidants relative to the oil in a buffer solution of pH 7 (No. 9477, Merck, Darmstadt, D) with 0.1% emulsifier by shaking vigorously under nitrogen atmosphere for 30 minutes, which is emulsified by 6 consecutive steps at 30 ° C in a microfluidizer H 5000. The oxidative stability of the emulsion is then measured with the help of a TRI OX EO 200® electrode coupled with a meter oxygen OXI 530®. It is allowed to take 5 to 10 minutes until the percentage of oxygen saturation has a constant value. This measurement is carried out at 30 ° C, with stirring in a closed vessel, after the addition of 5 ml of Hemin catalyst (Fluka AG, Buchs, CH) to 100 ml of emulsion. The Hemin catalyst is prepared from 52 mg of Hemin in 100 ml of water, to which 8 drops of 10% KOH are added. The induction time represents the duration, in hours, for the total absorption of the dissolved oxygen.

The Rancimat test at 110 ° C in various fats and oils and the oxygen electrode method at 30 ° C in maize oil gives the antioxidant power in the form of antioxidant values indicated in Table II below.

Comparative Example ii The procedure is carried out in the manner described in Example 2, except for the fact that the crushed green olives are not dried. The Rancimat® test at 110 ° C in chicken fat or in olive oil, and the oxygen electrode method at 30 ° C in maize oil give the antioxidant power in the form of antioxidant values indicated in Table "II plus The value of the incubation time at 120 ° C for the lipic fraction is described in Table III below.

Example 3 The procedure is carried out in the manner described in Example 1, except for the fact that the dried olives are preheated to 70 ° C for 60 minutes before being pressed. After cooling to room temperature, the pressing is carried out at room temperature in a Carver® type piston press at 500 bar for 60 minutes. The lipid fraction enriched with antioxidants and the oil cake are thus recovered. The induction time for the lipid fraction is measured by means of the Rancimat® test at 120 ° C. The value of the induction time for the lipid fraction is described in Table III below. In addition, 50 g of the recovered oil cake is extracted, at a high temperature with 1,2-propylene glycol. To do this, 50 g of 1,2-propylene glycol are added to the 50 g of the oil cake. The whole is kept stirred for 60 minutes at 80 ° C and the mixture is pressed on a Carver type piston press, a 500 barias for 60 minutes. The extract enriched with antioxidants is recovered. The Rancimat® test at 110 ° C in chicken fat in olive oil, and the oxygen electrode method at 30 ° C in corn oil, give the antioxidant power in the form of antioxidant values indicated in Table II described above. ahead.

Example 4 The procedure is carried out in the manner described in Example 2, except for the fact that 50 g of the recovered oil cake are extracted at high temperature with MCT. To do this, 50 mg of MCT are added to the 50 g of the oil cake. The whole is left stirring for 60 minutes at 80 ° C and the mixture is pressed on a Carver type piston press at 500 bar for 60 minutes. The extract enriched with antioxidants is recovered. The Rancimat® test at 110 ° C in chicken fat or in olive oil, and the oxygen electrode method at 30 ° C in corn oil, give the antioxidant power in the form of antioxidant values indicated in Table II described later.

Comparative Example iv The procedure is carried out in the manner described in Example 4, except for the fact that the ground green olives are not dried. The Rancimat® test at 110 ° C in chicken fat or in olive oil, and the oxygen electrode method at 30 ° C in maize oil, give the antioxidant power in the form of antioxidant values in Table II described above. ahead.

Example 5 The procedure is carried out in the manner described in Example 4, except for the fact that the dried green olives are preheated to 70 ° C for 60 minutes before being pressed. After cooling to room temperature, the pressing is carried out at room temperature in a piston press, of the Carver® type, at 500 bars for 60 minutes. The lipid fraction enriched with antioxidant and the oil cake are thus recovered.

The induction time is measured by means of the Rancimat® test at 120 ° C from 1% of the lipid fraction recovered in this way. In addition, 50 g of the recovered oil cake are extracted at high temperature with MCT. To do this, 50 g of MCT are added to the 50 g of the oil cake. The whole is kept stirred for 60 minutes at 80 ° C and the mixture is pressed in a Carver type piston press at 500 bar for 60 minutes. The extract enriched with antioxidants is recovered. The Rancimat® test at 110 ° C in chicken fat and in olive oil, and the oxygen electrode method at 30 ° C in corn oil, give the antioxidant power in the form of antioxidant values indicated in the Table II next.

Table II All measurements are made in the presence of 1% of the extract in relation to corn oil, in relation to corn fat or in relation to olive oil. -: not tested The measurements of the antioxidant power, indicated in the form of the antioxidant value, respectively in Examples 2 and ii and in Examples 4 and iv in Table II, show an increase in the oxidative stability of the extract enriched with antioxidant, obtained from the oil cake, in the case where the crushed green olives are dried. In addition, measurements of the antioxidant power, indicated in the form of the antioxidant value, respectively in Examples 2 and 3 and in Examples 4 and 5 in Table II, show that if the dried green olives are pressed at high temperature, the extract enriched with antioxidants, coming from the oil cake, it has a lower oxidative stability. Finally, the measurements of the antioxidant power, indicated in the form of the antioxidant value in the oxygen electrode test in Examples 2 and 3, show the quality and oxidative stability of the antioxidant compounds in emulsion, in comparison with the results obtained in an oil in the Rancimat® oxidation test.

Table III The measurements of the antioxidant power, indicated in the induction time form, in Table III show that if the dried green olives are preheated before being pressed at room temperature, the lipid fraction enriched with antioxidants has an increased oxidative stability.

Example 6 The procedure is carried out in the manner described in Example 2, except for the fact that the olives are ripe olives. The Rancimat® test at 110 ° C in chicken fat and the oxygen electrode method at 30 ° C in corn oil give the antioxidant power in the form of antioxidant values indicated in Table IV described below.

Comparative Example vi The procedure is carried out in the manner described in Example ii, except for the fact that the olives are ripe olives. The Rancimat® test at 110 ° C in chicken fat and the oxygen electrode method at 30 ° C in corn oil give the antioxidant power in the form of antioxidant values indicated in Table IV described below.

Example 7 The procedure is carried out in the manner described in Example 4, except for the fact that the olives are ripe olives. The Rancimat® test at 110 ° C in chicken fat and the electrode method of oxygen at 30 ° C in corn oil give the antioxidant power in the form of antioxidant values indicated in Table IV described below.

Comparative Example vii The procedure is carried out in the manner described in Example iv, except for the fact that the olives are ripe olives. The Rancimat® test at 110 ° C in chicken fat and the oxygen electrode method at 30 ° C in corn oil give the antioxidant power in the form of antioxidant values indicated in Table IV described below.

Table IV All measurements are carried out in the presence of 1% of the extract in relation to corn oil or in relation to chicken fat.

The measurements of the antioxidant power, indicated in the form of the antioxidant value, respectively in Examples 6 and vi and in Examples 7 and vii in Table IV, show an increase in the oxidative stability of the extract enriched with antioxidant obtained from the oil cake, in the case where the ripe olives and previously crushed are dried.

Example 8 A non-virgin, commercial olive oil (olio Sasso®) is stabilized with an olive extract enriched with antioxidants, which is prepared according to Example 1. 2 g of the extract is added to 100 g of the olive oil and obtains an oil which is 3.8 times more protected than the oil without the extract by measuring "the antioxidant power in the form of an antioxidant value in the Rancimat® test at 110 ° C.

Example 9 A pesto sauce is prepared which contains an extract enriched with antioxidant, as obtained in Example 4. To do this, prepare a mixture for the pesto sauce, with stirring at room temperature, containing per kg of sauce, 463.5 g of a mixture of olive oil and sunflower oil, 165 g of basil, 164 g of grated Parmesan cheese, 73 g of whey powder, 72.5 g of parsley, 45 g of ground pine nuts, 7 g of salt, 8 g of lyophilized garlic and 2 g of ground white pepper. 2% of the extract enriched with antioxidant is then added to this mixture, while stirring, to distribute the extract homogeneously in the pesto sauce prepared in this way. This pesto sauce is then packed in 100 g plastic tubes, which are then stored at 4-7 ° C.

Example 10 A pesto sauce is prepared which contains a lipid fraction enriched with antioxidant, as obtained in Example 3. To do this, a mixture for the pesto sauce is prepared, with stirring at room temperature, containing per kg of sauce, 233.5 g of lipid fraction enriched with antioxidants, 230 g of sunflower oil, 165 g of basil, 164 g of grated parmesan cheese, 72.5 g of whey powder, 45 g of ground pine nuts, 7 g of salt, 8 g of lyophilized garlic and 2 g of ground white pepper. This pesto sauce is then packaged in 100 g plastic tubes which were stored at 4 -7 ° C.

Example 11 A tomato sauce containing a lipid fraction enriched with antioxidant is prepared, as obtained in Example 5. To do this, a mixture for tomato sauce, with stirring at 50 ° C, containing per kg of sauce, 302.4 g of tomato puree, 30 g of lipid fraction enriched with antioxidants, 34.5 g of starch, 17 g of sugar, 2.5 g of lyophilized onions, 0.9 g of ground white pepper, 8.5 g of salt, 2.5 g of oregano, 0.4 g of finely crumbled basil and 601.3 g of water. The tomato sauce prepared in this way is then packaged, at room temperature, in 150 g cans hermetically sealed.

Example 12 A tomato sauce containing the extract enriched with antioxidant is prepared, as obtained in Example 1. To do this, prepare a mixture for the tomato sauce, with stirring at 50 ° C, containing per kg of sauce, 302.4 g of tomato puree, 30 g of sunflower oil, 34.5 g of starch, 17 g of sugar, 2.5 g of lyophilized onions, 0.9 g of ground white pepper, 8.5 g of salt, 2.5 g of oregano, 0.4 g of basil finely crumbled and 601.3 g of water. 2% of the extract enriched with antioxidant is then added to this mixture, while stirring to distribute the extract homogeneously in the tomato sauce prepared in this way. The tomato sauce prepared in this way is then packaged at room temperature in 150 g hermetically sealed cans.

Claims (12)

1. A process for the extraction of antioxidants from olives, in which: - the olives are crushed, - these crushed olives are dried under vacuum to obtain dried olives rich in water-soluble antioxidants, - these dried olives are pressed to recover a lipid fraction enriched with antioxidants, and an oil cake. at least one extraction is carried out on the oil cake at high temperature with MCT, or with an alkylene glycol of 2 to 6 carbon atoms using a pressure greater than or equal to 40 bar, and then an extract enriched with antioxidants is recovered from the Oil Cake.

2. The process according to claim 1, wherein the olives are green olives and / or ripe olives.

3. The process according to claim 1, wherein the olives are frozen olives.

4. The process according to claim 1, wherein the crushed olives are dried under vacuum at a temperature that is less than or equal to 80 ° C, to obtain dried olives rich in water-soluble antioxidants, and whose total water content is from 1 - 20% by weight.

5. The process according to claim 1, wherein the dried olives have a total water content of 5-10% by weight.

6. The process according to claim 1, wherein at least one extraction is carried out on the oil cake in a weight ratio of MCT or alkylene glycol of 2 to 6 carbon atoms / oil cake, from 0.5 to 2.

7. The process according to claim 1, wherein the alkylene glycol of 2 to 6 carbon atoms is glycol, 1,2-propylene glycol or 1,3-butylene glycol.

8. The lipid fraction enriched with antioxidants, whose induction time is 15 - 75 h at 110 - 120 ° C.

9. The extract enriched with antioxidants, which is capable of being obtained using the process according to any of claims 1 to 7.

10. The extract enriched with antioxidants according to claim 9, which comprises water-soluble antioxidants in particular.

11. The food or cosmetic composition, comprising 0.5-4% by weight of the extract enriched with antioxidants, which is obtained using the process according to any of claims 1 to 7.

12. The food or cosmetic composition, comprising a lipid fraction enriched with antioxidants, which is obtained using the process according to claim 1.