The invention is directed to a citrus halves cutting apparatus. The invention is also directed to a process to process citrus halves and especially to prepare citrus fibre from citrus halves.

US3952647 described an apparatus to separate a citrus peel into a albedo and flavedo fraction. The apparatus is fed by citrus peel parts which are supplied to two spaced apart rotating drums from a supply positioned above the two drums. The citrus peel parts will be gripped by one of the two drums depending on their orientation. The albedo side of the citrus peel part will grip into one of the drums and this drum will direct the peel part to a knife which separates the albedo from the flavedo. The apparatus thus has two knifes for cutting the citrus parts as they are supplied by either one of the two drums. A disadvantage of this apparatus is that the citrus peel has to be cut into parts which are substantially flat. Further two knives are required making the apparatus complex.

US4526794 describes a process to make a citrus fibre bulking agent by first separating the flavedo from the albedo.

US2799218 describes a machine to orient peel halves. The machine and method involves vibrating the peel halves over a downwardly inclined tray while water is sprayed from above to wash the peel halves and lubricate the surface of the tray.

US3072161 describes a citrus peel cutting machine where citrus peel halves are first cut in two parts resulting in citrus peel quarters. The citrus peel quarters are subsequently moved to a fixed knife to separate the albedo from the flavedo. A disadvantage of this method and machine is that it requires two cutting stages.

Multari et al., Flavedo and albedo of five citrus fruits from Southern Italy: physicochemical characteristics and enzyme-assisted extraction of phenolic compounds Journal of Food Measurement and Characterization (2021 ) 15:1754- 1762, htps://doi.Org/10.1007/s11694-020-00787-5 describes that the albedo of a citrus peel has a better holding water capacity than the flavedo of the same citrus peel.

Although it seems that fibres having better water holding capacity may be obtained when starting from the albedo of a citrus fruit many practical issues remain. The main reason is that it is laborious to isolate the albedo from the citrus fruit.

The present invention aims at providing an apparatus which can separate the albedo from a citrus fruit in a more simple manner than in the prior art.

This aim is achieved with the following apparatus. A citrus halves cutting apparatus comprising of

- a citrus halve conveyor comprising an endless belt and having an upstream end and a downstream end and suited to support and transport a citrus halve from its upstream end to its downstream end,

- an elongated knife positioned at the downstream end of the citrus halve conveyor for cutting the citrus halve in an upper cut part and a lower cut part, wherein the elongated knife is arranged to make a traverse movement in a direction which is perpendicular to the direction of the endless belt of the citrus halve conveyor,

- a pressing conveyor comprising an endless belt positioned above part of the citrus halve conveyor for fixing and transporting the citrus halve to the knife,

- a first discharge for the upper cut part comprised of a cuttings conveyor comprising an endless belt and having an upstream end and a downstream end and suited to support and transport the upper cut part away from the knife and to its downstream end and wherein part of the pressing conveyor is positioned above at least part of the cuttings conveyor and

- a second discharge positioned below the knife for the lower cut part.

Applicant found that the apparatus according to the invention can effectively separate the flavedo from the albedo starting from citrus peel halves in a more simple manner than disclosed in for US3072161. The apparatus can effectively separate the citrus halve into a lower part enriched in albedo and an upper part enriched in flavedo starting from the citrus halve itself. Thus no prior cutting of the citrus halve in a citrus peel quarter as in US3072161 is required. Thus the citrus peel does not have to be cut into smaller substantially flat parts. This enables one to directly use the citrus peel halves which are collected from retail juicing machines. The machine is suitably used to cut of an upper cut part of a citrus halve, wherein the upper cut part consists of primarily flavedo and some albedo, from a lower cut part comprising albedo and a content of flavedo and a content of juice vesicles.

The first discharge is comprised of a cuttings conveyor comprising an endless belt and having an upstream end and a downstream end and suited to support and transport the upper cut part away from the knife and to its downstream end and wherein part of the pressing conveyor is positioned above at least part of the cuttings conveyor. Because the pressing conveyor is positioned above at least part of the cuttings conveyor the upper cut part may be transporting away from the knife in an efficient manner. This because the upper cut part will be fixed between the co- directional moving endless belt of the cuttings conveyor and the endless belt of the pressing conveyor.

The invention is thus also directed to a process to process citrus halves by:

(a) arranging the citrus halves to a belly up orientation

(b) fixing the citrus halves obtained in step (a) between an upper and a lower moving conveyor belt and moving the citrus halves towards a knife by means of the moving upper and lower conveyor belts,

(c) cutting the citrus halve with the knife into a lower part enriched in albedo and an upper part enriched in flavedo, wherein in step (c) cutting is performed by an elongated knife which makes a traverse movement in a direction which is perpendicular to the direction of the upper and lower endless belts and transporting the upper cut part away from the knife by fixing the upper cut part between a third moving conveyor belt and part of the upper conveyor belt and

(d) separately collecting the upper parts and the lower parts obtained in step (c).

It has been found that fibres may be produced from the lower cut part by this process having a water holding capacity close to the water holding capacity when starting from a pure albedo feedstock. Further the upper cut part may be advantageously be used to make a candied citrus peel.

For this reason the invention is also directed to the following process to prepare a feedstock for a citrus fibre and for a candied citrus peel starting from a citrus halve having a top end and an open bottom end and wherein the citrus halve contains juice vesicles by

(a) pressing the citrus halve such that the distance between top end and bottom end is decreased,

(b) cutting the pressed citrus halve into an upper cut halve and a lower cut halve wherein the upper cut part is the candied citrus peel feedstock and comprises the top end of the citrus halve and is rich in flavedo and comprises albedo and does not comprise juice vesicles in any significant amount, and wherein the lower cut part is the citrus fibre feedstock and comprises the lower end of the citrus halve and is rich in albedo and further comprises flavedo and the juice vesicles.

Further advantages will be discussed below when describing the invention in more detail.

The citrus halve cutting apparatus is suitably an apparatus wherein between the elongated knife and the downstream end of the citrus halve conveyor a shaft is present. This shaft can rotate in the same direction as the endless belt of the citrus halve conveyor. The shaft is provided with gripping means for transporting the citrus halve to the knife. Such gripping means may be the ribs on the drums described in the earlier referred to US3952647. Suitably the gripping means are spaced apart sprockets. The citrus halves are impaled onto the ribs or sprockets by the pressing force of the pressing conveyor and conveyed by the rotating shaft towards the elongated knife.

The elongated knife may be a static knife and suitably a moving knife. Preferably the elongated knife is arranged to make a traverse movement in a direction which is perpendicular to the direction of the endless belt of the citrus halve conveyor. The distance moved of the knife in one direction may be between 1 and 5 cm and the frequency of the traverse movement may be between 80 and 120 movements per minute, wherein a movement is the movement of the knife in one direction and back to its starting point. The material of the knife may be steel and preferably a hardened stainless steel.

The endless belt of the citrus halve conveyor, the endless belt of the pressing conveyor and the optional endless belt of the cuttings conveyor may be driven by separate motors. Preferably the two or preferably three mentioned endless belts are driven by a single, preferably electrical, motor. The endless belt conveyor will then be driven via belts directly or indirectly connected to the drive axle of the motor.

The endless belt of the pressing conveyor is suitably moveable in a vertical direction to control the pressure on the citrus halves and the pressure of the upper cut parts in the preferred embodiment described above. By moving the endless belt of the pressing conveyor downwards the space between the endless belt of the pressing conveyor and the endless belt of the citrus halve conveyor and the optional endless belt of the cuttings conveyor will decrease resulting in that the citrus halves and optionally the upper cut parts are more firmly fixed between the belts. Being able to control this pressure is advantageous because too much pressure might result in damage of the citrus halves while too little pressure may result in that the citrus halves or upper cut parts are not transported to and from the elongated knife.

The invention is also directed to a citrus halve cutting configuration comprising a citrus halve cutting apparatus according to this invention and a citrus halves supply zone functionally arranged with the upstream end of the citrus halves conveyor. The citrus halves supply zone comprises of a water bath for floating citrus halves, means to arrange a flow of water and citrus halves from the upstream end to the downstream end of the supply zone of the water bath and means to discharge water to the water bath from above. The flow of water may be simply achieved by a recycle conduit provided with a pump to recycle water from the downstream end to the upstream end. The means to discharge water to the water bath from above may be any means which result in that a flow of water is sprayed or falls onto the floating citrus halves. It has been found that as a result any belly down positioned citrus halves topple to belly up directed citrus halves because of this spay or falling water. The means to discharge water to the water bath from above may be downwardly directed jets or a curtain of falling water.

By belly up and belly down is meant the following. A citrus halve is defined as having a top end and an open bottom end. The open bottom end is circular. A belly up positioned citrus halve is a citrus halve wherein the top end is the upper end and the open bottom end is the lower end. A belly down positioned citrus halve will have the open bottom end pointing upwards. When water is injected in this opening from above the citrus halve topples to the belly up position.

From the downstream end of the water bath the belly up citrus halves are collected and transported to the citrus halve cutting apparatus. This may be by means of the citrus halves conveyor or by means of a supply conveyor which can transport the belly up citrus halves from the downstream end of the water bath to the upstream end of the citrus halves conveyor. The supply conveyor is suitably an endless belt conveyor.

The invention is also directed to the following water bath for positioning floating citrus halves in said water bath comprising of an elongated water bath, means to create a flow of water from an upstream end of the water bath to a downstream end of the water bath and means to supply one or more jets of water from a position above the water bath. The flow of water will transport the floating citrus halves from the upstream end to the downstream end of the water bath and during this transport the citrus halves will be sprayed from above by the waterjets. The number of jets is suitably such that all of the floating citrus halves as they pass the jets contact the waterjets. The spacing between two adjacent waterjets will thus be less than the diameter of the citrus fruit. In this way it is ensured that at least one waterjet will inject water to a belly down citrus halve which forces the citrus halve to topple to a belly up position. The water bath may in addition be used to wash the citrus peel and remove any contaminants.

Such a process and water bath is preferred over a mechanical vibrating tray as disclosed in US2799218 because it avoids moving parts and is easier to keep clean. The invention is also directed to a process to process citrus halves by:

(a) arranging the citrus halves to a belly up orientation

(b) fixing the citrus halves obtained in step (a) between an upper and a lower moving conveyor belt and moving the citrus halves towards a knife by means of the moving upper and lower conveyor belts,

(c) cutting the citrus halve with the knife into a lower part enriched in albedo and an upper part enriched in flavedo, and

(d) separately collecting the upper parts and the lower parts obtained in step (c).

The citrus halves are preferably obtained in a process where the citrus fruit 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 halves as described in for example WO 2004/052126, US5170699, US2007074630. The citrus halves obtained after extracting the juice are suitably used as the starting citrus halves for the present process.

The citrus 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. Further the citrus halves suitably have not been subjected to a mechanical oil extraction because the citrus halves would then not have enough mechanical strength to be cut by the apparatus of this invention.

In step (a) the floating citrus halves with a belly down orientation are suitably toppled to a belly up orientation by injecting a downwardly projected waterjet into the citrus halves with a belly down orientation as here described.

In the process the cutting in step (c) is suitably performed by an elongated knife which makes a traverse movement in a direction which is perpendicular to the direction of the upper and lower endless belts. The process is preferably performed in the citrus halve cutting apparatus according to the present invention.

In step (c) the citrus halve is cut into a lower part enriched in albedo and an upper part enriched in flavedo. Preferably the lower part enriched in albedo is between 50 and 80 wt% and more preferably between 60 and 70 wt% of the starting citrus halve. When the citrus halve comprises of juice vesicles it is preferred that the cutting is performed such that more than 90 wt% and even more preferred more than 98 wt% of the juice vesicles of the starting citrus halve is present in the lower part.

Preferably the lower parts enriched in albedo are used to make a citrus fibre. In such a process it is preferred that the collected lower parts enriched in albedo are subjected to a homogenisation treatment to obtain a homogenized fraction. The homogenized fraction is contacted with an organic solvent to obtain an organic solvent washed citrus fraction. By separating the organic solvent and water from the organic solvent washed citrus fraction the citrus fibre is obtained.

In the above process to prepare citrus fibre it is preferred to first reduce the collected lower parts enriched in albedo to particles having a smaller size, preferably having a size smaller than 5 mm and even more preferably smaller than 0.5 mm. Such particle size reduction may be performed by for example cutting and/or tearing. Preferably the smaller size particles are obtained by colloid milling of the collected lower parts enriched in albedo.

The homogenization treatment may be effected by a number of possible methods including, but not limited thereto, high shear treatment, pressure homogenization, colloidal milling, intensive blending, extrusion, ultrasonic treatment, and combinations thereof. Preferably the homogenization treatment is a pressure homogenization treatment. Pressure homogenizers typically comprise a reciprocating plunger or piston-type pump together with a homogenizing valve assembly affixed to the discharge end of the homogenizer. Suitable high pressure homogenizers include high pressure homogenizers manufactured by GEA Niro Soavi, of Parma (Italy), such as the NS Series, or the homogenizers of the Gaulin and Rannie series manufactured by APV Corporation of Everett, Massachusetts (US). For other process conditions reference is made to the earlier referred to W012016190.

The homogenized fraction is contacted with an organic solvent to obtain an organic solvent washed citrus fraction. By contacting with the organic solvent water, flavours, odours, colours and the like are extracted from the homogenized fraction. The solvent should preferably be polar and water-miscible to better facilitate removal of the desired components. Examples of suitable solvents are lower alcohols such as methanol, ethanol, propanol, isopropanol butanol or acetone. Preferred solvents are ethanol, isopropanol, and combinations thereof. The solvent may be provided in aqueous solution.

Preferably, the homogenized fraction is contacted with the organic solvent at a solids-to-solvent weight ratio of at least about 0.25: 1 , preferably at least about 0.5:1 , and often at least about 0.75: 1 , from about 1 : 1 to about 5:1 , or from about 1.5:1 to about 3: 1 , based on the wet weight of the solids. In one embodiment, the solids-to- solvent ratio is about 2:1 .

The extraction with a solvent may be performed in a single stage but preferably is performed using multistage extraction, e.g., a two-, three-, or four-staged extraction process, and preferably using countercurrent extraction.

The organic solvent and water is separated from the organic solvent washed citrus fraction to obtain the citrus fibre. This may be by means of filtration, centrifugal forces and/or by drying. Preferably water and organic solvent are separated from the citrus fibre by a drying process. Examples of drying processes are vacuum drying, freeze drying and drying with hot air. Examples for drying processes resulting in evaporation of water and organic solvent are for example described W012016190, WO201 8/119058 and WO2017/023722. Drying may be performed by indirect heating, for example by contacting a heated vessel mantle, wherein the vessel is further provided with rotary conveyors for moving the citrus fibre in a horizontal direction. Alternatively drying may be performed by contacting with hot air at a temperature of between 40 and 70 °C, preferably between 55 and 60 °C. In the drying step a citrus fibre having a dry matter content of more than 90 wt% and preferably more than 93 wt% is obtained.

The organic solvent is preferably reclaimed from the gaseous mixture obtained in the drying step. Suitably water is suitably removed from the used organic solvent by for example distillation and/or pervaporation. For example isopropanol is suitably purified to a water content of below 5 wt%.

The invention will be illustrated by the following examples

Example 1

The example was performed using citrus halves as obtained from a juice extraction process in a retail environment where consumers extract juice and squeezed out citrus halves remain as a by-product. The citrus halves were cut in the apparatus according to this invention wherein 67 wt% of the starting citrus halve was the lower cut part and 33 wt% was the upper cut part. The lower cut part was enriched in albedo and contained some flavedo and juice vesicles. 640 weight parts of these lower cut parts were mixed with 1000 weight parts of tap water. This mixture was wet-milled, first by immersion blender and subsequently by IKA Ultra-turrax, to a particle size of <0.5 mm. The milled peel-water mixture was homogenised using a dairy industry homogenizer GEA Niro Soavi TwinPanda 600, having 2 plungers and a two-stage homogenisation valve. In a first stage the pressure drop was 360 bar and in a second stage the pressure dop was 40 bar. 560 weight parts of the homogenized fraction was contacted with 1000 weight parts of a water-isopropanol mixture (isopropanol content was 97 wt%) in 3 stages. The citrus fibres were subsequently dried to a 90% dry matter citrus fibre product.

The water holding capacity of the obtained citrus fibres were measured according to the following procedure. An empty 50mL tube was weighted with cap included. Approximately 1 ,0 gram of the obtained dried citrus fibre was added to the tube, and the exact weight was noted. Tap water was added to a total volume of approximately 50mL. The fibre and water were mixed by shaking. Within 10 minutes, the samples were spun in a centrifuge for 10 minutes at 3000RPM. The supernatant was poured off, and the tube with pellet were weighted. This weight was corrected for the weight of the tube and the weight of the fibre, with the remainder assumed to be bound water. The water holding capacity was defined as the amount of bound water (in gram) per gram fibre.

This example was repeated for 5 samples of orange citrus halves enriched in albedo over a period of 3 months. The average water holding capacity of the citrus fibres as obtained in these 12 examples is listed in Table 1 .

Comparative experiment A

Example 1 is repeated except that the citrus halves were not cut and thus not enriched in albedo for 10 samples. The citrus halves were obtained from the same batches as Example 1 in the same period. The average water holding capacity of the citrus fibres as obtained from these 10 samples is listed in Table 1.

Comparative experiment B

Example 1 is repeated except that only the albedo is used from the citrus halves for 12 samples. The albedo was manually separated from the flavedo and the juice vesicles. The citrus halves were obtained from the same batches as Example 1 in the same period. The average water holding capacity of the citrus fibres as obtained from these 12 samples is listed in Table 1.

Table 1 The results for the water holding capacity listed in Table 1 show that the fibres obtained in Example 1 are only slightly less good as the fibres obtained from the 100% albedo feedstock. This shows that the process to obtain the fibres from the lower cut parts of citrus halves may provide good quality fibres in combination with an automated process using suitably the apparatus of this invention.

The invention shall be illustrated by the following Figures.

Figure 1 shows a citrus halves cutting apparatus (1) according to this invention and provided with a citrus halve conveyor (2). The citrus halve conveyor (2) has an endless belt (3) and an upstream end (4) and a downstream end (5). An elongated knife (6) positioned at the downstream end (5) of the citrus halve conveyor (2). The knife (6) will in use cut the citrus halve in an upper cut part and a lower cut part. The upper cut part will be discharged to a container as first discharge (7) for the upper cut part and the lower cut part will be discharged to a container as second discharge (8) for the lower cut part as positioned below the knife (6). A pressing conveyor (9) is shown having an endless belt (10) positioned above part (11 ) of the citrus halve conveyor (2) for fixing and transporting the citrus halve to the knife (6).

The first discharge (7) is comprised of a cuttings conveyor (12) having an endless belt (13) and an upstream end (14) and a downstream end (15). The pressing conveyor (9) is positioned above at least part (16) of the cuttings conveyor (12) such to fix and transporting the upper cut part away from the knife (6) and towards the container of first discharge (7). Further a supply conveyor (17) is shown which supplies the citrus halves to the upstream end (4) of the citrus halves conveyor (2).

The pressing conveyor (9) is connected to an arm (18) connected to a frame (19) which extends above the plane of the citrus halve conveyor (2). In this manner the pressing conveyor (9) is pivotally supported from this higher elevation. An actuator (20) is present to arrange the pressure between the pressing conveyor (9) and the citrus halve conveyor (2) and cuttings conveyor (12). Figure 2 shows a detail of the citrus halves cutting apparatus (1 ) of Figure 1 . A single electrical motor (13a) drives the endless belt (3) of citrus halve conveyor (2). In Figure 5 it will be shown how this motor (13a) drives all endless belts (3,10,13) of apparatus (1 ). Between the elongated knife (6) and the downstream end (5) of the citrus halve conveyor (2) a shaft (14) is present. The shaft (14) rotates in the same direction as the endless belt (3) of the citrus halve conveyor (2). The shaft (14) is driven by electrical motor (13a) via a drive belt (15a). The endless belt (3) of citrus halve conveyor (2) runs via belt rollers (16a) and a belt tensioner (17) located below the endless belt (3). The endless belt (13) of cuttings conveyor (12) runs via belt rollers (18a), a belt tensioner (19) and a belt pully (21 ) located below the endless belt (13).

Figure 3 shows a detail of Figure 2.

Figure 4 shows shaft (14) provided with spaced apart sprockets (22) for transporting the citrus halve to the knife (6). At one end of the shaft (14) a belt pully (23) is shown for operation with drive belt (15a) of Figure 2.

Figure 5 shows a detail of Figure 2 but then viewed from the opposite side than the view of Figure 3. In this Figure the transverse moving knife (6) is seen in more detail. In use a citrus halve travels between endless belts (3) and (10) towards shaft (14) where sprockets (22) force the citrus halve towards knife (6). The upper half cut is then guided by endless belt (10) towards part (16) of the cuttings conveyor (12). At part (16) endless belts (10) and (13) move the upper half cut part away and towards the container of first discharge (7). The lower cut part as obtained in the cutting process of knife (6) is further transported by sprockets (22) to fall by gravity towards the second discharge (8) for the lower cut part.

Figure 6 shows how the endless belt (10) of the pressing conveyor (9), the endless belt (13) of the cuttings conveyor (12) and the shaft (14) are driven by drive belts which drive belts are driven by single motor (13a). Single motor (13a) directly drives the endless belt (3) of the citrus halve conveyor (2). The endless belts are not shown in this figure to improve clarity. Drive belt (24) drives belt pully (21 ) of the endless belt (13) of the cuttings conveyor (12). Drive belt (25) drives a further drive belt (26) via belt pully (27). Drive belt (26) drives the endless belt (10) of the pressing conveyor (9) via drive pully (28). Figure 7 shows the citrus halves cutting apparatus (1 ) of Figure 1 with a supply conveyor (17) provided with an endless belt (30). The supply conveyor (17) picks up belly up citrus halves which float in water bath (31 ) and transports the citrus halves to the upstream end (4) of the citrus halves conveyor (2). The water bath (31 ) is provided with a citrus halves positioner (32) comprising of a conduit positioned above water bath (31 ). The conduit is provided with openings (33) for upwardly ejecting pressurised water resulting in that the water falls down unto the floating citrus halves. In Figure 8 it is shown that the water (34) falls down upon the floating citrus halves (35,36) in water bath (31) where the belly down positioned citrus halves (35) topple to belly up positioned citrus halves (36). By means of a water current in the water bath the citrus halves move from right to left in Figure 8.