WO2007042742A1

WO2007042742A1 - Cured olive powder

Info

Publication number: WO2007042742A1
Application number: PCT/GB2006/003060
Authority: WO
Inventors: Albert Zumbe
Original assignee: Albert Zumbe
Priority date: 2005-10-07
Filing date: 2006-08-17
Publication date: 2007-04-19
Also published as: GB0518264D0

Abstract

Cured olive powder and paste are made from olive cake or alpeorujo which are by- products in olive oil production. Olive cake and alpeorujo are very acrid and bitter making them very unpalatable for use in food for human consumption except in very small quantities. This invention relates to the dcbi tiering and fermentation process of olive cake obtained from all types of olive fruit to enable both the olive paste or powder to be used as a culinary ingredient and for dietary supplements. The use of the word 'cured' in this text is meant to cover “ alkaline treatment in combination with natural fermentation in brine, or fermentation with brine treatment alone.” Fermentation is key to product stable, tasty and palatable product.

Description

CURED OLIVE POWDER.

The present invention relates to cured olive powder and paste for use as a culinary ingredient.

DESCRIPTION

TECHNICAL FIELD OF THE INVENTION

The olive tree is grown over all the five continents, although it is especially prevalent in the Mediterranean Basin which represents by far the greatest olive production area. The main products are olive oil and table olives. The world production of olive oil is in the order of 3,000,000 tonnes per year and the world production of table olives is in the order of 1 ,5000,000 tonnes per year ( figures quoted by the International Olive Oil Council) with a constant growth due to increased product familiarity, improved quality, association to the healthy Mediterranean diet and increased purchasing power.

The nutritional properties of olive oil with its high content of monosaturated fatty acids and the presence of several other constituents in the olive such as polyphenols, tocopherols, chlorophyll, pheophytin, sterols, squalene, aroma and flavour compounds is well documented in the scientific literature.

The principal technologies are extraction by pressure ( known as the "old method or three phase method" ) and extraction by centrifugation ( known as the " new method or two phase method" ).

In the old method the whole olives are ground to produce a paste, the olive paste is then spread on fibre disks, which are stacked on top of each other, then placed in a press. These disks are then put on a hydraulic piston, forming a pile. Pressure is applied on the discs, this compacting the solid phase of the olive paste and percolating the liquid phases ( i.e the olive oil and vegetation water). Pressures of up to 400 atm are used. The liquids are then separated by decantation or a vertical centrifuge. The solid phase is called the olive cake or orujo and the vegetation water is called alpechin

In the modern method of oil extraction the olives are crushed Io a fine paste using a rotating mechanical mill to enable the agglomeration of small olive droplets, The paste is then pumped to an industrial decanter where the phases are separated and to facilitate the extraction process with the paste a certain quantity of water is added. This type of decanter has two exits, the water is expelled by the decanter coil together with the pomicc, resulting in a wetter pomice called alpeorujo. There are variations to this process but essentially it is about milling, decanting and centrifugation; to obtain alpeorojo in the decanter and the vegetation water. The non oil fractions are by products have been considered as waste, although in the last few years various applications have been developed. These include composting, electricity generation ( from the energy of combustion ), anti-fungal compounds for treatment of plant diseases, in animal feed, in cosmetics, for the extraction of nutraceutical ingredients for human consumption and the production of olive paste or olive powder. The olive paste and powder are extremely bitter and totally unpalatable for use as a food ingredient except in very small quantities.

However in spite of this the technology used to manufacture olive oil still results in a massive amount of waste product. More often than not when not used the olive cake and alpeorujo are simply deposited in the area around the oil extraction plants where, due to their long period of degradation, they pollute the environment. Furthermore, the vegetation waters create a large quantity of polluting effluents, 100 kg of olives process using the old method of pressure extraction create 100 litres of vegetation water and this puts into prospective the amounts that are produced in the oil extraction areas.

DESCRIPTION OF THE PRIOR ART for olive paste and olive powder made from olive cake and alpcorujo.

Crude olive paste has been around for thousands of years ever since man extracted oil from crushed olives,

Olive pastes are available whereby extra olive oil is added and mixed in with crushed olive cake or alpeorujo. The mass may be pasteurised or sterilized to further stabiles the product.

Aqueous olive paste can be obtained by breaking up the olive cake ( orujo) or alpeorujo and separating out the stones by screening or ventilation. Additional water is then mixed into the de-stoned mass to attain the required viscous texture followed stabilisation by heat treatment ( either pasteurised or sterilisation). Alternatively the aqueous olive paste can be stabilised by combination by a mixture of acidifying agents and preservatives, or by refrigeration. The aqueous acid paste can also be preserved with nitrogen or carbon dioxide. This type of paste is very bitter and can only be consumed in small quantities usually mixed with other food ingredients to improve the taste and or to dilute out some of the bitterness.

Olive powder has been described in the literature for use in animal feed ( Acta Vet.Bruno 1990, 68: 91 -98 ) and a more detailed process is described in the patent application { WO2004110171 ), Essentially, fresh olive cake or alpeorujo is sieved to remove the stones , and the remaining material dried for example in a vacuum drier or in a fluidised bed preferably at a relatively low temperature of less than 6OC ( to avoid the creation of harmful breakdown metabolites) and then milled to the required particle size in a hammer mill to 2 mm or for example a pin mill to with α cryogenic system to less than 0.075 mm. This olive powder will also be very bitter and somewhat unpalatable without the addition of large quantities of other ingredients to improve the taste and or dilute out some of the bitterness. The patent however describes the first known attempt to manufacture a reduced fat olive powder for human food usage.

Interest in olive powder is particularly interesting in view of its abundance and low cost. Whilst it is not very nutritional in terms of protein quality and therefore of limited use in animal nutrition. The renewed interest for human nutrition of olive cake and alpeorujo is in the relatively low net carbohydrate , high fibre and antioxidant content and also the anti -microbial properties ( Innovations in Food Technology, February ) . DESCRIPTION OF THE INVENTION

The main object of the present invention is to provide an improved process for The manufacture of a cured olive paste and olive powder for human consumption. These products are useful culinary ingredients which have much better organoleptic qualities than the natural uncured products already described.

In accordance with the present invention, it is better to use fresh olive cake or alpeorujo as these materials ore unstable and will spoil. Ideally the processing of these materials will be within about 5-10 hours of their production but this period can be prolonged by refrigeration or freezing of the materials prior to processing.

The olive cake or alpeorujo can be made from olive fruit of various stages of ripening from green, olives turning colour and black olives. The variety and degree of ripening will influence the final taste and aroma of the olive products described in this invention.

The olive cake and alpeorujo may be optionally de-fatted by solvent extract prior to the debittering process.

Furthermore, optionally the olive pits are separated and removed from the olive cake and alpeorujo by sieving to remove virtually all the pits, and this may be done prior to or after drying.

The important step of the present invention is the treatment of the olive cake and alpeorujo with lye or a mixture of both lye and brine. Many different variations of this essential process are possible by adding the reagents for example at the beginning of the process directly to the olive cake or alpeorujo or alternatively to the dried olive olive cake or alpeorujo.The lye can be replaced essentially by other alkalisation agents. Treatment of the dried olive cake or dried alpeorujo is preferred when the curing is carried out at a later date or at a different site to the preparation of the fresh olive cake or fresh alpeorujo.

The main point is that the olive cake and alpeorujo is treated with alkaline and packed in brine to undergo complete natural lactic acid fermentation or partial natural lactic acid fermentation. The fermentation occurs by naturally occurring bacteria which converts the sugars into lactic acid which then acts as a preservative. Yeasts may also play a role in the fermentation as they will contribute to the taste and aroma of the olives, If the fermentation is not complete the paste is then optionally heat treated by sterilisation or pasteurisation, or the addition of preservatives, or refrigeration or treatment with nitrogen or carbon dioxide or simply stored in brine.

Alkalisation treatment with solutions or suspensions of alkali , usually in the form of sodium hydroxide, but other pH agents for alkalisation include for example ammonium carbonate, ammonium hydroxide, ammonium hydrogen carbonate, calcium carbonate, magnesium ammonium hydroxide, calcium carbonate, Magnesium carbonate, magnesium hydroxide, potassium carbonate, potassium hydroxide, potassium hydrogen carbonate, sodium carbonate, sodium hydroxide, sodium hydroxide carbonate and calcium hydroxide. As the olive fruit broken up during grinding for the olive oil production, the olive fresh and the pant cells are broken up which in turn speeds up the alkalisation process as opposed a similar treatment of intact olive fruit. The process has to be fine tuned to avoid soapy rancidity and for this the acidification is practised after the alkalisation step. Such acids may include for example lactic acid , citric acid . L ( + ) tartaric acid, acetic acid, carbon dioxide, L-ascorbic acid. Acidification may of course be created by natural lactic fermentation of the olive cake and alpeorujo the brine, which another key process step described in this innovation.

Whilst brine is ideal to permit the natural lactic fermentation, other salt solution alternatives can used. Low sodium alternatives would include for example potassium chloride.

Alternatively, the olive cake or alpeorujo can be cured by directly placing in brine and preserved by natural fermentation ( without alkalisation treatment). An alternative to brine is rock salt ( sodium chloride or dried sea salt.

DETAILED DESCRIPTION OF THE INVENTION

EXAMPLE l

Olive cake is placed in a tank and to it is added an equivalent volume of lye ( 2% of sodium hydroxide solution) with continuous stirring for at least 2 hours. The water is then drained off, though a filter or by centrifugation. The alkalised olive mass is then washed again optionally 1 -3 times, each time stirring for one hour and the excess water is drained off. A brine solution is made up and 1% glacial acetic acid or lactic acid ( 1litre to 100 litres ) is added. This brine solution with added acid is then added to the water washed olive cake. Air is excluded and the mixture is left to ferment for 6 weeks. It may be necessary to release pressure every week if the drum is well sealed. White substances ( which are moulds and yeasts) may appear on the surface of the liquid and should be removed. The progress of the fermentation is very important as it will produce stable and tasty olive cake. The excess brine is then drained off and the mass is dried in a vacuum drier or a fluid bed at less than 6OC. The dried mass is then milled to the required size or converted to pellets by dry compacting.

EXAMPLE 2

As in example I except that the stating material is died alpeorujo passed though a hammer mill to approx 2mm in diameter.

EXAMPLE 3

As in example except that pasteurised olive paste made form olive cake is the starting substrate. In this case the volume mix is olive paste to lye 60: 40.

EXAMPLE 4

To the alpeorujo is added an equivalent volume of brine ( 10% brine solution). The tank or drum filled to the brim; the pressure is released every week if the recipient is well sealed. The fermentation is left to take place , preferably but not limited to 2-6 months. After fizziness has disappeared and the pH has stabilised to around 4, the fermentation will have been completed. The excess brine is then washed off and the mass is dried in a vacuum drier or a fluid bed or other from of drying for example pan drier or tray drier or the sun. The drying process should preferably not exceed 6OC although higher temperatures up to 11OC have been used. The dried mass is then milled to the required size, converted to pellets by dry compacting, or adjusted to the appropriate size.

EXAMPLE S

The olive cake is washed at least once with an equivalent volume of water as described in example 1, and to the washed olive cake is added an equivalent volume of 10% brine solution. The process is then similar as described in example 4.

EXAMPLE 6

As in examples 1 , 3, 4 and 5 in which the cured dried olive cake or cured dried alpeorujo is agglomerated. The fermented olive cake or alpeorujo powder is suspended in fluidised mass and water or steam or a solution there of, which contains a binder is sprayed into the suspended mass. Binders may include up to a 5% aqueous solution of gum, alginate or carrageen.

EXAMPLE 7

The fermented olive cake and alpeorujo as produced in 1 , 3, 4 or 5 is freeze dried. Cured olive cake or alpeorujo is mixed with water ( with up to an equivalent weight of water at up to 40C with high speed homogenation. The suspension was stabilised by pre-cooling to - 4C using a scraped surface heat exchanger before deep frozen to below 40C using cold air blasting. The deep frozen mass was granulated and sieved at a temperature not exceeding -40C using an atlas granulator and sieve. Sieving was used to regulate the granule size to not Less than 0.5 mm and not greater than.5 mm, This granulated mass was transferred to trays and freeze dried at 0.4 mbar pressure with product not exceeding 40C.

EXAMPLE 8

To the washed and drained olive cake or alpeorujo or olive powder, preferably made from ripe olive is added a layer of coarse salt ( sodium chloride or sea salt ) . This is repeated until the container is full. Once a week the mass is mixed and turned on its side to drain liquid. This is left for 2 -3 months, until the level of bitterness is acceptable . Rinse off excess salt pieces and remove the excess water by filtration or by centrifugation , and dry in for example a vacuum drier or dredge in virgin olive oil.

EXAMPLE 10

To the fresh olive cake or alpeorujo is mixed in sufficient dry comestible powder ( for example flour, starch or dried olive powder; but preferable of high acid comestible powder in the region of pH 4 ) in order to reduce the water activity sufficiently to inhibit spoilage by bacteria, yeast or moulds. This mass is then fermented in brine in brine at a later date or alternative location as in for example 1, 3, 4 or 5.

Claims

CLAIMS.

1. A method for producing a cured reduced fat olive fruit paste made from either one or a combination of the following: a) from olive cake which is essentially extraction by pressure. b) from alpeorujo which is essentially extraction by centri fugation. c) from olive vegitation water. d) the residue of solvent extraction of olive cake, alpeorujo or other olive derivative of the olive fruit.

Curing in this innovation is meant to cover "alkaline treatment in combination with natural fermentation in brine, or fermentation with brine alone. Fermentation is essential to produce stable, tasty and palatable product.

2. A method for producing a cured reduced fat olive fruit powder from either one or a combination of the following: a) from olive cake which is essentially extraction by pressure. b) from alpeorujo which is essentially extraction by centriftigation, c) solids recuperated from olive vegitation water. d) the residue of solvent extraction of olive cake, alpeorujo or other olive derivatives of the olive fruit.

Curing in this innovation is meant to cover "alkaline treatment in combination with natural fermentation in brine, or fermentation with brine alone. Fermentation is is essential to produce stable, tasty and palatable product.

3. A method for producing a cured reduced fat olive fruit granule from either one or a combination of the materials in 1 a , b , c or d in claim 1. The granules are made by either:

- dry compacting ( optionally with a binding agent)

- agglomeration (with water or steam optionally with a binding agent)

- freeze drying technology

- optionally milling or breaking up the dried mass to a targe particle size of above 0.55 mm

Fermentation is essential to produce stable, tasty and palatable product.

4. A method as claimed in claims 1 -3, whereby the debittering agent is lye.

5. A method as claimed in claims 1 - 3 .whereby the debittering agent is an alkaline solution( for example: ammonium carbonate, ammonium hydroxide, ammonium hydrogen carbonate, calcium carbonate, magnesium carbonate, potassium carbonate, potassium carbonate, potassium hydrogen carbonate, calcium hydroxide either singularly or in combination of one or more of these chemical compounds ).

6. A method as in claims 1 -3 , whereby the curing is carried out by a combination of lye ( or an alternative alkaline solution) with brine

7. A method whereby the oxidation of the olive paste, fat olive powder and granules described in claims 1 -3 is maximised by treating the olive cake or alpeorujo by one or a combination of the following processes. a) injecting air or oxygen b) increasing the pH c) adding an oxidation agent d) use of enzyme technology

8. A method whereby the reduced olive fat powder or agglomerate as in claims 2 and 3 is re-hydrated and cured and/or oxidised by the processes listed in claim 4-7 , and then optionally dried or made into a aqueous paste.

9. A method in which the olive derivative fruit materials listed in claim 1 used to make reduced fat olive paste, powder or agglomerate is further reduced in fat by solvent extraction either prior to the curing process step or alter the curing steps or alter drying the olive powder

10. A method in which the cured reduced fat olive powder or agglomerate in claim 3 is further reduced in fat by solvent extraction either prior to the curing process or after the curing process or after drying the olive powder.

11. A method as in claims 1 to 3 whereby the olive cake or alpeorujo used to make cured reduced fat olive paste, powder or agglomerate is partly or virtually fully de-stoned ( pitted).

12. A method by which the starting material for making cured olive paste, powder or agglomerate is olive leaf.

13. A method by which the olive cake or alpeorujo or other olive derivative is washed extensively with water ( by rinsing in water and separating out the solids by pressure or centrifugation in one or more cycles of re-soaking) prior to conversion to cured olive paste or cured olive powder as in claims 1-3.

14. A method by which the polyphenols in the olive cake, alpeorujo or other olive derivatives are extracted by the use of food solvents including but not limited to aqueous alcoholic mixes prior to the curing processes described in claims 1 -14 ( but not including claim 8 )

15. A method as in the claims claims 1 -14 in which the olive fruit is bruised , de-stoned ( pitted ) olives, slices or diced olives used are blanched.

16. A method as in claims 1-3 above whereby the sodium chloride in the brine is wholly or partially replaced by an alternative non sodium salt including for example potassium chloride.

17. A method as in claim 1-3 by which the natural fermentation in the cured olive paste is replaced by an alternative acidification agent (; or where there is insufficient acidification to avoid spoilage by the addition of preservatives ( for example but not limited to benzoic acid and its sodium and potassium salts or sorbic acid and its sodium and potassium salts ) or heat treatment. ( sterilization or pasteurisation or Ultra Heat Treatment).

18. A method as in claims 1-3 in which thickeners and agglutinants or firming agents are added to the olive paste and/or the olive powder or olive granules.

19. A method as in claims 1-3 in which cultures of lactic micro-organisms are used for the curing process.

20. A method as in claims 1-3 in which the olive cake or alpeorujo are treated with ionising irradiation prior to or after the curing process.

21. A method as in claim 1 in which the fermentation is carried out with added solid salt (sodium chloride) particles or solid sea salt particles to either ; a) olive cake or b) alpeorujo or c) other olive fruit residues

A salt solution or salt suspension is not added.