Flash fruit sugar removal

Abstract

The present invention provides a method for deacidification and / or extraction of sugars from fruit juice. Fruit juice is deacidified on a weak anion exchange resin to obtain a deacidified juice with a pH increase of at least 0.2. The deacidified juice is eluted on a strong cation exchange resin at a temperature of 5 to 8 °C to extract 30 to 50 % of total sugars from the juice. In the present disclosure, the strong cation exchange resin is a Na + form resin.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 570984, filed March 28, 2024, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure relates to fruit juice products with reduced acidity and partially or completely reduced sugar content, and methods for providing said products. Background Technology

[0004] Fruit juices such as orange and apple juice are widely accepted and popular. One problem with drinking these juices is their acidity, which varies depending on terroir, climate, origin, and harvest time, and may cause discomfort for individuals with sensitive stomachs. A second issue is the sugar content for individuals who are dieting and / or trying to reduce their daily sugar intake. Almost all apple and orange juices contain significant amounts of sugar, with fructose making up a substantial proportion.

[0005] It is known that buffers and certain chemicals or enzymes are added to raise the pH of orange juice. However, these are undesirable exogenous agents. The strong demand and desire of consumers to no longer see chemical reagents and artificial additives in fruit and juice processing has spurred thought and technical work in the search for natural and physical methods.

[0006] Some literature also documents that low-pH orange juice is unfavorable for the growth of certain pathogenic microorganisms (such as Clostridium botulinum). Since these microorganisms are more likely to grow at pH levels above 4.6, low-acid juices may require more aggressive heat treatment to prevent microbial growth. However, such treatment may lead to the deterioration of certain sensitive compounds or loss of flavor.

[0007] Therefore, it is desirable to reduce the acidity (or increase the pH) of orange juice in a controlled manner without adding additives, in order to avoid the need for aggressive heat treatment.

[0008] Vitamin C, also known as ascorbic acid, is present in significant amounts in orange juice and is a vitamin found in various foods and dietary supplements. It has been used to prevent and treat scurvy and is an essential nutrient involved in tissue repair, certain enzymatic processes, and is necessary for the function of many enzymes.

[0009] Ascorbic acid is a vinylogous acid, and it forms the ascorbate anion when one of its cyclic hydroxyl groups is deprotonated. Ascorbic acid readily forms its sodium, potassium, and calcium salts and is commonly used as an antioxidant. Therefore, it is desirable to retain ascorbic acid in orange juice.

[0010] Sucrose, glucose, and fructose are carbohydrates (or sugars) also found naturally in orange and apple juice. Sugar plays an important technical role, contributing to the sweetness of products and performing other functions such as flavor enhancement. However, the beverage industry faces immense pressure to reduce sugar content. Health-related studies have shown a link between sugary beverage consumption and weight gain in children and adults due to imbalanced energy intake. Discussions have indicated that long-term consumption of sugary drinks not only affects weight but also leads to elevated triglyceride levels in the blood. High-fructose corn syrup (HFCS) is the most difficult to hydrolyze, thus it can accumulate on the liver and contribute to type 2 diabetes.

[0011] In North America, a "sweetened product" is defined as containing 15 g of sugar per 250 mL of a given beverage. Therefore, the goal is to reduce the sugar content to below that amount (equivalent to 6% or 60 g / L).

[0012] To reduce sugar content, some methods dilute the sugar concentration with fruit juices (such as coconut water or maple water). Furthermore, existing methods are known to alter flavor and texture, and further change the composition of natural nutrients such as beta-carotene and vitamin C. Another option is to replace natural sugars with artificial sweeteners. However, one risk associated with these issues is the potential alteration of the juice's flavor and texture.

[0013] Sugar reduction in orange juice has also been demonstrated by elution with a weak anion exchange resin (see, for example, WO2022049490). However, further improvements are expected, particularly in elution and process time, and in reducing sugar content (to achieve total sugar below 6%).

[0014] In addition, it is hoped that the process can be modified to extract sugar from other juices such as apple juice. Summary of the Invention

[0015] In a first aspect, a method is provided for deacidifying and / or extracting sugars from fruit juice while retaining the original nutrients, the method comprising: deacidifying the fruit juice on a weak anion exchange resin to obtain a deacidified fruit juice with a pH increase of at least 0.2; and eluting the deacidified fruit juice on a strong cation exchange resin at a temperature of 5°C to 8°C to extract 30% to 50% of the total sugars from the fruit juice; wherein the strong cation exchange resin is Na₂SO₄. + Type of resin.

[0016] In some embodiments, the juice is derived from coffee extract or from citrus fruits. In one embodiment, the citrus fruits are oranges, blood oranges, lemons, grapefruits, tangerines, clementines, kumquats, calamansi, black grapes, white grapes, dragon fruit, soursop, mangosteen, guava, pomegranate, persimmon, lychee, mangosteen, papaya, passion fruit, annona, sapotille, apple, or combinations thereof. In one specific embodiment, the juice is derived from orange juice or apple juice. In this embodiment, the method further includes pretreating the juice to remove some of the pulp before eluting and deacidifying the juice, for example, removing about 2% to 50% of the pulp. Optionally, the pretreatment includes clarifying the juice. Pretreatment may include centrifugation and / or filtration.

[0017] In some embodiments, the elution step on a strong cation exchange resin is performed in less than 1 hour and achieves a reduction of at least 2 Brix.

[0018] In some embodiments, the elution step on a strong cation exchange resin is carried out in less than 1 hour, and a reduction of at least 2% by weight in total sugar content is achieved.

[0019] In some implementations, the temperature is between 5.5°C and 7.5°C.

[0020] In some implementations, the temperature is 6°C to 7°C.

[0021] In some embodiments, the fruit juice is loaded onto a weak anion exchange resin at a loading of 75% to 125% of the calculated loading of the resin.

[0022] In some embodiments, the fruit juice is loaded onto a strong cation exchange resin at a loading of 75% to 125% of the calculated loading of the resin.

[0023] In some embodiments, the weak anion exchange resin is made of acrylic resin or styrene.

[0024] In some embodiments, the weak anion exchange resin is composed of sulfonate (SO3) groups. - It is made of polystyrene matrix with functional groups.

[0025] In some embodiments, the strong cation exchange resin is a copolymer of styrene and 5-15% by weight of divinylbenzene (DVB) having sulfonic acid exchange groups.

[0026] In some implementations, the pH of the deacidified fruit juice is less than 4.6.

[0027] In some implementations, the pH of the deacidified fruit juice is 3.5 to 4.5.

[0028] In some embodiments, the method further includes concentrating the juice. In such embodiments, the concentration step may be reverse osmosis or vacuum evaporation.

[0029] After reading this disclosure, those skilled in the art will understand many other features and combinations thereof that are relevant to the present improvement. Detailed Implementation

[0030] A method for deacidifying and / or extracting sugar from fruit juice is provided, the method comprising: deacidifying the fruit juice on a weak anion exchange resin to obtain a deacidified fruit juice with a pH increase of at least 0.2; and eluting the deacidified fruit juice on a strong cation exchange resin at a temperature of 5°C to 8°C to extract 30% to 50% of total sugar from the fruit juice; wherein the strong cation exchange resin is Na₂SO₄. + Type of resin.

[0031] The current flash method offers optimization for two consecutive and rapid stages of deacidification / desugaring, which are connected in a progressive and continuous manner, but are fast and effective in a very short time.

[0032] "BV" is an abbreviation for "bed volume," which is the volume of resin in a column. Furthermore, in the technical field of circulating fluids in resin-filled columns, the fluid flow rate is typically expressed in BV / hour. Its advantage lies in indicating the flow rate in a standardized way, independent of column volume.

[0033] As used in this article, the pH (pHe) of the juice at the column outlet during the deacidification process refers to the pH of the deacidified juice read after elution on a weak anion exchange resin but before the container containing the accumulated / combined deacidified juice.

[0034] The pH of the deacidified juice specified as pHd refers to the pH of the deacidified juice accumulated / combined according to the methods described herein. pHd is generally preferably obtained from deacidified juice accumulated / combined that has been substantially homogenized (e.g., by shaking or mixing).

[0035] In the deacidification process provided herein, the circulation rate of the juice in the column containing anion exchange resin can be varied, while being maintained between 5 BV / hour and 450 BV / hour, preferably between 5 BV / hour and 250 BV / hour, or more preferably between 5 BV / hour and 150 BV / hour.

[0036] In one embodiment, the volumetric loading (in BV) of the juice (e.g., orange juice) relative to the resin volume can be adjusted by those skilled in the art. For lower pH change requirements, the exchange capacity of a weak anion exchange resin is fixed and limited by the number of available active sites, and the working capacity, expressed in BV, increases at a given target pH. For example, at a given exchange capacity of about 1.4 equivalences per liter of resin, the BV of orange juice with an initial pH of about 4.3-4.4 may be about twice that of orange juice requiring a 1 pH reduction (e.g., from about 25 BV to about 50 BV) when a 0.5 pH reduction is required.

[0037] In one embodiment, the loading of juice on the resin (in BV) is preferably 75% to 125% of the calculated loading, or preferably 75% to 100% of the calculated maximum loading.

[0038] The juices envisioned in this disclosure include juices from citrus fruits such as oranges, blood oranges, lemons, grapefruits, tangerines, Clementine, kumquats, calamansi, black grapes, white grapes, dragon fruit, custard apples, mangoes, guavas, pomegranates, persimmons, lychees, mangosteens, papayas, passion fruit, custard apples, sapodilla, and apples. As juices, coffee extracts from ground coffee are also included.

[0039] In the method described herein, anion exchange resins are used to capture acid in order to adjust the acidity with extremely high precision, thereby deacidifying the juice. More specifically, the exchange of anions on the adsorbent (i.e., the resin, which is a polymer) with another anion occurs in the column.

[0040] The resins used for deacidification of fruit juices are weak anion exchange resins. For example, a weak anion exchange resin is a tertiary amine that is neutral at pH greater than 10 and ionizes at pH less than 10. Therefore, it should be understood that a weak exchange resin is a resin whose cationic functional groups dissociate according to the pH of the solution.

[0041] The advantage of weak anion exchange resins lies in their high specificity for weak acids and polybasic acids. However, as mentioned above, the juice to be deacidified may contain citric acid and ascorbic acid, wherein citric acid has three pKas (i.e., acidity constants) at 25°C, namely pKa1 of about 2.9, pKa2 of 4.3-4.4, and pKa3 of 5.2; and ascorbic acid has a pKa of about 4.1-4.2.

[0042] As included in this article, a "weak acid" refers to an acid that does not completely dissociate in water. The higher the pKa of an acid, the weaker it is.

[0043] Preferably, the anion exchange resin is an acrylic or styrene-based resin. Advantageously, it is an acrylic anion exchange resin. The acrylic anion exchange resin preferably has a capacity of 1.6-3.2. The resin also exhibits an initial exchange rate equal to or greater than +0.10 pH units / min observed after contacting the fruit juice to be deacidified with the resin at a volume ratio of 5:1 (juice:resin) for 5 minutes. The particle size of the resin varies from 300 μM to 600 μM. An example of a weak acrylic anion exchange resin is that produced by DOW CHEMICAL under the trade name AMBERLITE. TM The CR5550 model is for sale.

[0044] In one embodiment of the method, the pH (pHe) of the deacidified juice at the column outlet does not exceed pH 5 for any significant period of time, for example, not exceeding one pH unit in a series of pH readings taken at fixed intervals of 5 minutes. Preferably, the pHd value of the deacidified juice is from about 4 to less than about 5, preferably less than about 4.6 or from about 4.2 to about 4.6.

[0045] Regarding orange juice, selectively capturing a portion of citric acid while retaining ascorbic acid is particularly advantageous and rapid (a flash process) during the deacidification process according to the method of the present invention. In practice, some citric acid needs to be removed to deacidify the orange juice and make it more palatable to people with sensitive stomachs without dilution and / or the addition of other sugars or buffers; however, sufficient amounts of citric acid and as many other components as possible (such as ascorbic acid) need to be retained, which also contribute to the juice's beneficial health and / or flavor properties. In some embodiments, depending on the pKa values ​​of citric acid and ascorbic acid, if selective capture of a portion of citric acid is desired, the pH (pHe) of the deacidified orange juice at the column outlet can be approximately pKa1 citric acid < pHe < pKa2 citric acid.

[0046] Furthermore, the deacidification method described in this paper can maintain the pH of fruit juice (such as orange juice or apple juice) at a level below that which effectively prevents microbial growth, for example, below about 4.6.

[0047] The deacidification method described herein does not require the use of acids (e.g., solutions containing citric acid, malic acid, ascorbic acid, or combinations thereof) to deactivate the reactive portion of the anion exchange resin.

[0048] In one embodiment, the method includes a pretreatment step of the juice to be deacidified. This pretreatment step may include clarifying the juice using any existing technology fully understood by those skilled in the art. This is particularly useful for orange juice due to the presence of pulp. Examples of such clarification techniques include centrifugation and filtration (especially membrane, diatomaceous earth, or plate and frame filtration). For example, clarification is advantageously carried out until a juice with a turbidity below 500 NTU (scattered turbidity units), preferably below 100, more preferably below 25 NTU is obtained. This pretreatment step has the advantage of preventing column clogging. Optionally, the pulp is reinjected into the orange juice after processing.

[0049] A regeneration step of the anion exchange resin can be performed so that the same resin can be used for another deacidification of the juice.

[0050] In one embodiment, the deacidification device includes multiple columns, preferably 2-10, more preferably 3-6. The implementation of multiple columns is known to those skilled in the art. In one embodiment, the juice is partially circulated in a loop such that after leaving the columns, a first portion of the deacidified juice re-enters a container configured to contain the juice to be deacidified, and a second portion of the deacidified juice enters a container for receiving the deacidified juice. The implementation of partial circulation in the loop is known to those skilled in the art.

[0051] In a preferred embodiment, the deacidified fruit juice of this disclosure does not contain added sugar, masking agents (e.g., alkali or chelating agents), or buffers. Preferably, the pH of the deacidified fruit juice is from about 3.5 to less than about 4.6, more preferably less than about 4.6 or from about 3.7 to about 4.6.

[0052] At the end of the deacidification stage, the method may further include a step of concentrating the deacidified orange juice using one or more techniques known to those skilled in the art (e.g., reverse osmosis or evaporation). Therefore, the deacidified orange juice may or may not be concentrated before the sugar reduction process. For example, the concentration index of the deacidified orange juice may be from about 5 to about 65 Brix, preferably from about 35 to about 50 Brix or about 50 Brix.

[0053] Furthermore, byproducts and sugar residues are recovered during the recycling process and column discharge. These sweet orange extracts, or fruit-derived sweeteners, are highly valuable to manufacturers. Once concentrated to 70 Brix, they can be used in small quantities as flavor enhancers and fruit sugars in any food formulation.

[0054] For sugar extraction, this method provides a resin that is a strong acid cation exchange resin. The resin is composed of resins containing sulfonate (SO32-) groups. - The polystyrene matrix is ​​composed of functional groups. The cation in a strong acid cation exchange resin is Na₂O. + Instead of H +Or other cations. Strong cation Na + These resins can be used without buffers and alcohol-based regeneration solvents. They are specific for the absorption of small sugars such as glucose, fructose, and sucrose. In one example, a strong cation exchange resin is DYNASPHER. TM Na + Type of resin. In some embodiments, the strong cation exchange resin is a gel-type strong acid cation exchange resin provided in sodium form. In some embodiments, the gel is a copolymer of styrene and 5-15% by weight of divinylbenzene (DVB) having sulfate exchange groups.

[0055] The resin disclosed herein has a particle size of 300 μM to 600 μM.

[0056] In one embodiment, the capacity of the strong acid cation exchange resin is about 1.4-1.8 equivalents / liter.

[0057] The strong cation exchange resin is preferably conditioned prior to the desiccant process. Conditioning can be performed using an aqueous solution containing citric acid / citrate at pHi and pHd, or between pHi and pHd, where pHi is the pH of the orange juice to be deacidified and pHd is the pH of the deacidified orange juice, and conditioning is performed prior to the desiccant process. For example, the resin can be conditioned using a volume of orange juice, deacidified orange juice, or a buffered citric acid solution, wherein the pH of the juice or solution is from about 3 to about 4.6, preferably deacidified orange juice, with pHd satisfying: pHi + (0.1–1) < pHd < 5, preferably from about 4.3 to 4.6. It is preferred to condition the resin using a buffered citric acid solution having pHd as defined herein, which is from about 4.0 to 4.6. It is preferred to condition the resin using about 1 BV to 3 BV of the above-described conditioning solution. It is also preferred to wash the resin with water after conditioning.

[0058] After conditioning the strong cation exchange resin, a certain volume of fruit juice (preferably deacidified according to the method described herein) is eluted onto the resin. Preferably, the volumetric loading of the fruit juice is about 1% to about 10% of the resin volume, more preferably about 5%.

[0059] The method provides to selectively recover a first portion of the sugar-reduced juice to provide sugar-reduced juice, the first portion comprising about 50% to about 70% by weight, preferably 60% to 70% by weight, of the total sugar content of the juice, for example, recovering x BV of the eluted juice, where x is 0.1 to 0.8.

[0060] The method also provides for the additional recovery of a fructose-rich second portion from deacidified fruit juice.

[0061] In the step of eluting a certain volume of deacidified fruit juice to be desugared, the step includes eluting the volume of deacidified fruit juice on a resin, followed by elution with water (preferably deionized water) until the recovered first portion contains about 30% to about 80% by weight of the total sugar content of the deacidified fruit juice. In some embodiments, the total sugar content remaining in the juice is 4% to less than 6% by weight, 4.5% to 5.9% by weight, or 5% to 5.9% by weight. The lowest possible sugar content is still desirable to provide the desired taste and nutritional value.

[0062] Preferably, the elution of the juice is carried out on a column containing a strong cation exchange resin, with the elution direction being from top to bottom. The elution rate is preferably from about 1 to about 10 BV / h, or from about 2 to about 5 BV / h, or from about 4 to about 5 BV / h.

[0063] Preferably, the juice is eluted on a column containing a strong cation exchange resin, thereby cooling the juice to a desired temperature (5°C to 8°C, 5.5°C to 7.5°C, 6°C to 7°C) before the elution step, and / or the column containing the strong cation exchange resin is thermostatically controlled (e.g., by means of a jacketed column) to maintain the above temperature.

[0064] Surprisingly, it was found that, especially when fruit juices (such as orange or apple juice) were cooled to a temperature range of 6°C to 7°C, the effect was related to Na. + A combination of strong cation exchange resins reduces elution time and improves sugar removal performance, as shown in the examples below.

[0065] In some embodiments, the sugar extraction step of this method can be considered a flash sugar extraction. In fact, in preferred embodiments, elution in a strong cation exchange resin lasts for less than 1 hour, less than 55 minutes, or less than 50 minutes, achieving a reduction in Brix of at least 2, at least 2.1, at least 2.2, at least 2.3, at least 2.4, or at least 2.5. In other embodiments, elution in a strong cation exchange resin lasts for less than 1 hour, less than 55 minutes, or less than 50 minutes, achieving a reduction in total sugar content of at least 2.5 wt%, at least 2.6 wt%, at least 2.7 wt%, at least 2.8 wt%, at least 2.9 wt%, or at least 3 wt%. When performing the above elution, the pump is considered to be running at a flow rate of 40%-70%, preferably starting at about 50%, and may decrease to about 40% during the elution run. The sugar content correction margin obtained by the flash sugar extraction method described herein is up to 60%, and the desugared product has good sensory quality.

[0066] The deacidification step is also considered to be a flash deacidification because the pH increases significantly in less than 1 minute.

[0067] Example 1: Room temperature sugar removal from apple juice

[0068] The method was tested on two different fruit juices (orange juice and apple juice). The aim was to reduce acidity (i.e., increase pH) and sugar content (by at least 40%-50%). When removing acidity and sugar, it is important not to degrade, hydrolyze, or remove the nutritional molecules in the juice (such as vitamin C in orange juice).

[0069] The initial solution of concentrated apple juice with a Brix of 69.1 was diluted to obtain apple juice with a Brix of 10.8. The initial temperature of the apple juice was 24.2℃ and the pH was 3.33. A total mass of 12.4 g of apple juice was deacidified in a weak anion exchange resin column (DYNASFER / TYCaSPHER - CGRCa Calcium).

[0070] Table 1. Deacidification of apple juice

[0071] The experiment ran for a total of 2 hours and 40 minutes until the resin was saturated. Even when the pump flow rate was reduced, only a small amount of deacidification was observed, and the pH increased by only 0.12. However, the Brix remained essentially unchanged during the deacidification process, indicating that no blockage occurred in the column.

[0072] The slightly deacidified apple juice was then subjected to a sugar extraction process. The resin used in the column for sugar extraction was DYNASPHER. TM CGR-Na, a type of Na + Strong cation exchange resins (and other H+) + (Resin relative). Before entering the column, the deacidified apple juice had a Brix of 10.3, a pH of 3.45, and a temperature of 24°C.

[0073] Table 2. Sugar extraction of deacidified apple juice at 24°C

[0074] Experiments were conducted until the resin's maximum desugaring capacity was reached. As shown in Table 2, the Brix of the apple juice decreased by 1.8, and the pH increased by 0.4.

[0075] Example 2: Cooling and sugar removal of apple juice

[0076] Concentrated apple juice with a Brix of 69.1 was diluted to a Brix of 11.9. 10.5 g of the diluted apple juice was deacidified at a temperature of 24°C and a pH of 3.29. The same weak anion exchange resin as in Example 1 was used.

[0077] Table 3. Deacidification of apple juice

[0078] The deacidification results were similar to those of Example 1. Brix decreased only slightly from 11.9 to 11.4, and the pH increased only slightly from 3.29 to 3.5. The deacidified apple juice was then placed in a refrigerator for 3 hours to lower its temperature to 6°C-7°C to remove sugars.

[0079] Therefore, in DYNASPHER TM Deacidified fruit juices processed in a CGR-Na strong cation exchange column exhibited a temperature of 6-7°C, a pH of 3.42, and a Brix level of 11.4.

[0080] Table 4. Sugar extraction of deacidified apple juice at 6℃-7℃

[0081] The experimental time for sugar removal from deacidified apple juice was significantly reduced to 35 minutes (compare Table 4 with Table 2), and more sugar was removed in a shorter time. In Example 1, 1.8 Brix was eliminated in 1 hour and 15 minutes; while in Example 2, 3.4 Brix was eliminated in 35 minutes. Therefore, it was surprisingly found that temperature has a significant effect on the rate of sugar extraction.

[0082] Example 3: Cooling and sugar removal of orange juice

[0083] Orange juice with a Brix of 10.4 and containing pulp was pretreated by centrifugation to reduce the pulp by approximately half (estimated to be 3% pulp remaining). 9.1 g of orange juice was deacidified. As previously described, the sample had an initial temperature of 11.4°C, a pH of 3.45, and a Brix of 10.4. The same weak anion exchange resin as in Example 1 was used.

[0084] Table 5. Deacidification of orange juice

[0085] Compared to deacidification of apple juice, deacidification of orange juice was much faster, and the pH increase was greater. Therefore, the same resin appears to have different performance for different juices. The column pH reached 6 within 20 minutes. It should also be noted that Brix decreased when deacidifying orange juice, in contrast to deacidification of apple juice. The column became clogged with orange pulp, which explains the decrease in Brix. This can also be explained by the significant reduction in acidity. As shown in Table 5, the pH increased by 0.53.

[0086] Then use DYNASPHER TM Deacidification of deacidified orange juice was performed using a CGR-Na strong cation exchange column. The deacidified orange juice sample was cooled to 3.5°C in a refrigerator and held for 3 hours, with an initial pH of 3.8 and a Brix value of 8.

[0087] Table 6. Sugar extraction of deacidified orange juice at 3.5℃

[0088] The sugar removal column was run until the resin was saturated. As shown in Table 6, the Brix decreased by 1 and the pH increased by 0.1.

[0089] Example 4: Cooling and sugar removal of orange juice within an improved temperature range

[0090] Orange juice with a Brix of 10.6 and containing pulp was pretreated by centrifugation to reduce the pulp by approximately half (estimated to be 3% pulp remaining). 10.2 g of orange juice was deacidified. As previously described, the sample had an initial temperature of 11.4°C, a pH of 3.48, and a Brix of 10.6. The same weak anion exchange resin as in Example 3 was used.

[0091] Table 7. Deacidification of Orange Juice

[0092] Compared to Example 3, the pump power was increased to reduce the residence time in the column. As can be seen from Table 7 (compared to Table 5), residence time is a factor in the deacidification rate. It should also be noted that Example 4 used the same resin as Example 3 and was not regenerated before operation. This is also a factor explaining the performance observed in Table 7.

[0093] Chill the desalted orange juice in the refrigerator to 6.9°C to remove sugar. Use DYNASPHER. TM CGR-Na strong cation exchange column. The pH of the deacidified orange juice was 3.6, and the Brix value was 9.6.

[0094] Table 8. Sugar extraction of deacidified orange juice at 6.9℃

[0095] Surprisingly, a temperature of 6°C–7°C was found to be preferred, and both lowering the temperature (see comparison with Example 3) and not cooling (see comparison between Examples 1 and 2) significantly accelerated the test time. In fact, the Brix decreased by 1.6 within 45 minutes; while in Example 3, the Brix decreased by only 1 within 1 hour.

[0096] Example 5: Analysis of sugar content

[0097] Analyze the specific molecular content of the following samples.

[0098] Table 9. Samples analyzed

[0099] To analyze the contents of the above samples, high-performance liquid chromatography (HPLC) was performed. TM HDO 125 The flow rate was 0.25 mL / min, 2.1 mm to 3 µm. The solvent was water containing 0.1% phosphoric acid for the first 7 minutes, followed by acetonitrile for up to 20 minutes at 40°C (injection volume 5 µL). Calibration was performed using four standard acids: malic acid, ascorbic acid, tartaric acid, and citric acid. For each of the 10 samples AJ, 1 gram was lyophilized to remove moisture. The mass loss during lyophilization was used to determine the moisture content of the sample.

[0100] The sample was salted as follows: Hexamethyldisilazane was added to anhydrous pyridine powder, followed by trimethylchlorosilane. After reacting for 12 hours, the supernatant was injected into a gas chromatograph and detection flame (the apparatus was lined with straight-chain alkanes C15-C20). Sugar content was measured using the Kovats retention index. Quantitative analysis was performed by adding sorbitol prior to salting, taking into account the response coefficients of the major sugars (fructose, glucose, galactose, and sucrose) and gluconic acid. Since the moisture content was determined beforehand by lyophilization, the results are expressed as a percentage.

[0101] Table 10. Acid content of sample AJ

[0102] Table 11. Moisture content of sample AE

[0103] Table 12. Sugar content of sample AJ

[0104] Table 13. Comparison of sugar content between sample B and sample A (sugar reduction of 38.86%)

[0105] Table 14. Comparison of sugar content between sample J and sample G (sugar reduction of 38.60%)

[0106] As can be seen from the table above, the sugar content of both orange juice and apple juice was reduced by approximately 30%-40%. This desired reduction in sugar content was achieved through the improved method described in the foregoing embodiments. A major advantage of this method is that it shortens the time required for sugar removal.

[0107] Example 6: Analysis of various resins in the column during flash sugar removal and / or deacidification

[0108] To verify the resin compatibility during flash sugar extraction and / or deacidification, columns containing 11 different resins were prepared. Juice was passed through at rates ranging from 2 to 250 L / h. This test allowed for resin saturation profile analysis, examination of resin behavior according to the product, control of regeneration and rinsing, and determination of the required bulk volume (BV) for pH adjustment based on the product.

[0109] The following combinations of resins were tested: - 50% LEWATIT TM S5221 / 50% DYNASPHER TM WAC6703-F - LEWATIT TM S5221, standalone - 50% DYNASPHER TM CGR-Na / 50% DYNASPHER TM CGR-Ca, mixture - PAD950C, standalone - DYNASPHER TM WAC6703-F Tests were conducted on deacidification of apple juice, orange juice, and cranberry juice, as well as desugaring of orange juice. The tests demonstrated that the DYNASPHER WAC6703-F resin is highly effective for deacidification. Resin regeneration during the desugaring process is carried out using water. Desugaring apple juice takes approximately 4 hours, while resin regeneration takes only 1 hour. Therefore, water regeneration and the propulsion of the sugar-loaded water column are instantaneous. For deacidification, the treatment time is measured in seconds (pH change of 0.2-0.3 within 20 seconds). However, regeneration requires 4 hours. The system can be operated continuously.

[0110] Although this disclosure has been described in conjunction with its specific embodiments, it should be understood that it is capable of further modifications, and this application is intended to cover any variations, uses, or adaptations, including deviations from this disclosure that are known or customary in the art and that may be applied to the essential features described herein and as defined by the appended claims.

Claims

1. A method for deacidifying and / or extracting sugar from fruit juice, the method comprising: The juice is deacidified on a weak anion exchange resin to obtain a deacidified juice with a pH increase of at least 0.2; and The deacidified fruit juice is eluted on a strong cation exchange resin at a temperature of 5°C to 8°C to extract 30% to 50% of the total sugar from the fruit juice. The strong cation exchange resin mentioned above is Na + Type of resin.

2. The method of claim 1, wherein the juice is derived from coffee extract or from citrus fruits.

3. The method of claim 2, wherein the citrus fruit is orange, blood orange, lemon, grapefruit, mandarin orange, Clementine, kumquat, calamansi, black grape, white grape, dragon fruit, custard apple, mango, guava, pomegranate, persimmon, lychee, mangosteen, papaya, passion fruit, custard apple, sapodilla, apple, or a combination thereof.

4. The method according to any one of claims 1-3, wherein the juice is orange juice or apple juice.

5. The method according to any one of claims 1-4, further comprising pretreating the juice to remove some of the pulp before eluting the deacidified juice.

6. The method of any one of claims 1-5, wherein the elution step on the strong cation exchange resin is carried out in less than 1 hour and achieves a reduction of at least 2 Brix.

7. The method of any one of claims 1-6, wherein the elution step on the strong cation exchange resin is carried out in less than 1 hour and achieves a reduction of at least 2% by weight in the total sugar content.

8. The method of any one of claims 1-7, wherein the temperature is 5.5°C to 7.5°C.

9. The method according to any one of claims 1-8, wherein the temperature is 6°C to 7°C.

10. The method of any one of claims 1-9, wherein the fruit juice is loaded onto the weak anion exchange resin at a loading amount of 75% to 125% of the calculated loading amount of the resin.

11. The method of any one of claims 1-10, wherein the fruit juice is loaded onto the strong cation exchange resin at a loading amount of 75% to 125% of the calculated loading amount of the resin.

12. The method according to any one of claims 1-11, wherein the weak anion exchange resin is made of acrylic resin or styrene.

13. The method according to any one of claims 1-12, wherein the weak anion exchange resin is composed of sulfonate (SO3) groups. - It is made from a polystyrene matrix with functional groups.

14. The method of any one of claims 1-13, wherein the strong cation exchange resin is a copolymer of styrene and 5-15% by weight of divinylbenzene (DVB) having sulfonic acid exchange groups.

15. The method of any one of claims 1-14, wherein the pH of the deacidified fruit juice is less than 4.

6.

16. The method of any one of claims 1-15, wherein the pH of the deacidified fruit juice is 3.5 to 4.

5.

17. The method of claim 5, wherein the pretreatment includes clarifying the juice.

18. The method of claim 17, wherein the pretreatment comprises centrifugation and / or filtration.

19. The method of claim 5, wherein about 50% of the pulp is removed.

20. The method of any one of claims 1-19, further comprising concentrating the juice.

21. The method of claim 20, wherein the concentration step is reverse osmosis or evaporation.

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