TECHNICAL FIELD

The present disclosure relates to extraction of phytochemicals from a coffee waste. More particularly, the present disclosure also relates to a method for extracting phytochemicals from a coffee pulp waste.

BACKGROUND

Coffee is one of the highly consumed beverages in world. The coffee can be produced from roasted seeds of plant thereof. Such a process involves removal of exocarp (outer skin), mesocarp (mucilage or pulp) and endocarp or parchment (inner layer) from the bean. Coffee processing can be carried out by two methods-dry and wet method. The dry method involves exposure of coffee cherries to the sun for drying. However, the wet method produces parchment or washed coffee which involves removal of the outer skin (exocarp) and mucilage or pulp (mesocarp) from the cherry using water until the exposure of the coffee bean thereto. Wet method of generating a by-product named coffee pulp, a mucilaginous liquid residue.

The primary processing of coffee generates a waste called coffee pulp, a mucilaginous residue. For every ton of coffee processed, 170-190 Kgs of pulp is released whose BOD levels range from 25,000-45,000 mg/L making it one of the worst liquid pollutants generated in farming activity, CPCB notified-red category.

Total Indian coffee production is approximately 3,34,000 tons of which 1,33,600 tons are produced as parchment. 13360 tons of mucilage are generated and are diluted with 8-12 liters of water that turns into 133600 liters of toxic effluent.

The coffee pulp has tannins and caffeine which render thereto toxic leading to serious issues of the disposal thereof. The coffee pulp gets often disposed into the water bodies, which may be harmful thereto. As the production thereof is more harmful to environment, the coffee pulp is discarded as a waste material with no beneficial use.

Presently, the coffee pulp extracting industries are disposing the waste into the environment by adding microbial consortium in order to reduce the biological oxygen demand (BOD) in the effluent to prevent the ecosystem. The presence of toxic chemicals like tannins, phenolic and alkaloids inhibits biological degradation that affects the ecosystem. Adding microbial consortium breaks down the toxic substances in the effluent water but adds on the cost hugely.

SUMMARY OF THE INVENTION

In one aspect of the disclosure, a method of extracting phytochemicals from coffee pulp waste is provided.

The method includes obtaining a coffee waste generated during a production of parchment of coffee, pre-processing the liquid coffee pulp waste obtained at step a to remove debris, adding 92-96% of a first solvent to a preprocessed coffee pulp waste obtained at step b in a ratio of 1:2 to 1:7 followed by centrifugation to obtain a pectin precipitate and a first supernatant, adding 95-98% of a second solvent in a ratio of 1:3 to 1:5 to the first supernatant obtained at step c followed by mixing and separating a solvent fraction to obtain another precipitate and a second supernatant, and distilling the second supernatant obtained at step d to obtain a polyphenol powder in form of phytochemical. The preprocessing is achieved by filtering through fruit pulper machine 45-75-micron mesh filter. The filter is filter press, nutsche filter press, plate, frame filter press, vertical filter press or belt filter press. The pre-processing is achieved by a fruit pulper machine with a screen of 20-400-micron. The first solvent is selected from a group comprising isopropyl alcohol, methanol, ethanol, hexane, acetate, acetone or ether. The second solvent is an acetate and is selected from a group comprising ethyl acetate, methyl acetate, sodium acetate, ammonium acetate, acetamide, propyl acetate or butyl acetate. The centrifugation is done at 800-2000 RPM centrifugal force on a continuous mode with a retention time of 2-8 minutes. The centrifuge is selected from a group comprising bowl centrifuge, Small Bench Centrifuges, Large Capacity Refrigerated Centrifuges, Refrigerated Centrifuges, Ultra Centrifuges, Fixed Angle Rotors, Vertical Tube Rotors, Zonal Rotors, Elutriator Rotors, continuous flow centrifuge, gas centrifuge, hematocrit centrifuge, microcentrifuge, vacuum centrifuge/concentrators, density gradient centrifuge, differential centrifuge, isopycnic centrifuge, sucrose gradient centrifuge, equilibrium density gradient centrifugation, differential velocity centrifugation. The pectin and the polyphenols are purified by decontaminator. The pectin and the polyphenols are dried and stored. The solvent is recovered by solvent separator. The phytochemical is selected from a group comprising pectin, polyphenols, Gallic acid, Coumaric acid, Ferulic acid, Cinnamic acid, Chlorogenic acid and Caffeic acid. BRIEF DESCRIPTION OF DRAWINGS

The drawing/s mentioned herein disclose exemplary embodiments of the claimed invention. Other objects, features, and advantages of the present invention will be apparent from the following description when read with reference to the accompanying drawing.

Figure 1 illustrates a polyphenol HPLC characterization graph of polyphenols, according to an embodiment herein; and

Figure 2 illustrates an elution profiles of the HPLC characterization polyphenol, according to an embodiment herein.

To facilitate understanding, like reference numerals have been used, where possible to designate like elements common to the figures.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This section is intended to provide explanation and description of various possible embodiments of the present invention. The embodiments used herein, and the various features and advantageous details thereof are explained more fully with reference to non-limiting embodiments illustrated in the accompanying drawing/s and detailed in the following description. The examples used herein are intended only to facilitate understanding of ways in which the embodiments may be practiced and to enable the person skilled in the art to practice the embodiments used herein. Also, the examples/embodiments described herein should not be construed as limiting the scope of the embodiments herein.

The coffee pulp waste is procured from Coffee growing regions of Karnataka, Tamil Nadu and Kerala, India.

The food waste defines as the non-edible part of the food, or the waste generated during the processing of food. The food waste is selected from a coffee pulp waste generated during the parchment of coffee.

Phytochemicals defines as the chemicals produced plants and includes pectin and polyphenols in the context.

In view of the drawbacks of the existing methods, the present method utilizes the waste from the effluent to produce the phytochemicals. As mentioned, there is a need to find alternatives to utilize the waste coffee pulp (liquid waste) produced during parchment of the coffee beans. The present disclosure overcomes the limitations of the prior arts by providing a method for extracting phytochemicals from coffee waste while overcoming toxicity by overcoming the problems associated with the biological oxygen demand by retrieving the effluent with low biological oxygen demand less than 1000 mg/L without a need for microorganism, thus minimizing the hazardous effect on the environment. The present disclosure also tackles the problem of the coffee industry related to the disposal of this toxic waste produced primarily in the eco-sensitive region of the Western Ghats.

Therefore, there exists a need to provide other method to utilize the waste- coffee pulp produced during parchment of the coffee to minimize the hazardous effect on the environment.

Coffee pulp waste is the waste obtained during the parchment of the coffee beans.

In an embodiment, the present disclosure provides a method for extracting phytochemicals from the coffee pulp waste.

The method comprises:

At step a, collecting the coffee pulp generated during the parchment of coffee.

At step b- preprocessing the raw coffee pulp waste obtained to remove debris and insoluble residues by 800-2000 RPM centrifugal force on a continuous mode with a retention time of 2- 8 minutes. In an embodiment, the pre-processing is achieved by a fruit pulper machine with a screen of 45-75-micron mesh filter. In another embodiment, the filter includes, but not limited to, filter press, nutsche filter press, plate, frame filter press, vertical filter press and belt filter press. In another embodiment the mesh size is 20-400-microns. In an embodiment, the debris is a bits of the fruits. In another embodiment, the debris is a fruit stalk. In another embodiment, the debris is a dried flower residues. In another embodiment, the debris is a leaves remains.

In another embodiment, for the preprocessing the centrifuge is selected from wherein the centrifuge is selected from a group comprising bowl centrifuge, Small Bench Centrifuges, Large Capacity Refrigerated Centrifuges, Refrigerated Centrifuges, Ultra Centrifuges, Fixed Angle Rotors, Vertical Tube Rotors, Zonal Rotors, Elutriator Rotors, continuous flow centrifuge, gas centrifuge, hematocrit centrifuge, microcentrifuge, vacuum centrifuge/concentrators, density gradient centrifuge, differential centrifuge, isopycnic centrifuge, sucrose gradient centrifuge, equilibrium density gradient centrifugation, differential velocity centrifugation. In another embodiment, the pre-process involves separating liquid and insoluble particles produced during the parchment. In another embodiment, the low-level centrifugal force is applied by a centrifuge. In another embodiment, the pre-processing involve separation of any debris or pulp still attached to the insoluble particles through abrasion.

At step c, adding 92-96% of a first solvent to the preprocessed coffee pulp waste in a ratio of 1:2 to 1:7 followed by centrifugation at 800-2000 RPM on a continuous mode with a retention time of 2-8 minutes to obtain a pectin precipitate and a first supernatant. In another embodiment, the solvent is a food grade solvent. In another embodiment, the solvent includes, not limited to, isopropyl alcohol, ethanol, acetate, acetone or hexane.

At step d, adding 95-98% of a second solvent in a ratio of 1:3 to 1:5 to the first supernatant obtained at step c followed by mixing and centrifugation at 800-2000 RPM with a retention time of 2-8 minutes to obtain a phase separation and a second supernatant. In an embodiment, the polyphenols are extracted by aqueous extraction. In another embodiment, the polyphenols are extracted by solvents such as ethyl or methyl or propyl acetate, acetone or hexane.

At step e, the second solvent fraction obtained at step d is further distilled to obtain a polyphenol powder. In an embodiment, the distillation is achieved by distiller. In another embodiment, the distiller is a pot still distiller. In another embodiment, the distiller is a column still distiller.

In another embodiment, a method for sequentially extracting pectin and polyphenols is provided herein. The method includes pre-processing of the coffee pulp followed by subjecting the pre-processed coffee pulp to food grade solvents such as ethanol, iso propyl alcohol. Such an exposure thereof may procure pectin. Thereafter, the method involves extracting polyphenol using a solvent such as acetate or a spent obtained as by-product of the preceding step. Another solvent such as acetates may be added thereto producing the polyphenol. Finally, water as an end product may be recycled back to use as a starting material in the pulping plant.

In another embodiment, a method includes extracting pectin from the coffee pulp is provided herein. The method includes pre-processing the coffee pulp produced during parchment of the coffee. The pre-processing involves separation of the debris and liquid from insoluble particles, and removal of pulp therefrom. The pulp may be subjected to solvents such as food grade solvents, producing the pectin. In yet another aspect, a method for extracting polyphenol during parchment of the coffee is provided herein. The pre-processing involves separation of the debris and liquid from insoluble particles, and removal of pulp therefrom. The pulp may be subjected to solvents such as food grade solvents, producing the pectin and leftover. The leftover may be further subjected to another solvent such as acetates, thereby producing the polyphenol.

In another embodiment, a method for removing toxicity of coffee pulp waste. The method includes pre-processing of the coffee pulp produced during the parchment of coffee. The pre processing involves separating the liquid and the insoluble particles produced during the parchment. Such a separation may require low levels of centrifugal forces. The pre-processing may also involve separation of any debris or pulp still attached to the insoluble particles through abrasion. The method further involves adding solvents to the coffee pulp retrieved, thereby removing toxicity therefrom. In yet another aspect, an integrated method for overcoming coffee waste toxicity along with extraction of phytochemicals. The method includes pre-processing of the coffee pulp produced during the parchment of coffee. The pre-processing involves separating the liquid and the insoluble particles produced during the parchment. Such a separation may require low levels of centrifugal forces. The pre-processing may also involve separation of any debris or pulp still attached to the insoluble particles through abrasion. The method further involves adding solvents to the coffee pulp retrieved and extracting pectin. In an embodiment, the solvent is a food grade solvent. Examples of the solvents may include such as but are not limited to isopropyl alcohol. Further, the method involves extracting the polyphenols using the remaining slurry of the coffee pulp, followed by retrieving end product as water. The water retrieved may be recycled to be used as the starting material required in the pulping plant.

Figure 1 illustrates a polyphenol HPFC characterization of polyphenols, according to an embodiment herein.

The obtained polyphenol powder is characterized by High performance liquid Chromatography to obtain a levels of Gallic acid, Coumaric acid, Ferulic acid, Cinnamic acid, Chlorogenic acid, and Caffeic acid.

Figure 2 illustrates an elution profiles of the HPFC characterization polyphenol, according to an embodiment herein.

The obtained polyphenol powder is characterized by high performance liquid chromatography to obtain an elution profiles of polyphenols. Examples

Example 1: Collection of Coffee pulp

The coffee pulp waste was procured from the coffee growing area of Tamil Nadu, Karnataka, Kerala and Andhra Pradesh, India.

The coffee pulp generated during the parchment of coffee was pre-processed to remove debris by centrifuge the coffee pulp waste at 1200 RPM, on a continuous mode with a retention time of 6 minutes.

Example 2: Extraction of phytochemicals from coffee pulp

The pre-processed coffee pulp waste was added with 92% of isopropyl alcohol in the ratio of 1:7 followed by centrifugation at 800 RPM on a continuous mode with a retention time of 4 minutes and Pectin was extracted from coffee pulp waste in the form of hydrocolloid and supernatant was collected.

The supernatant was added with 94% ethyl acetate in the ratio of 1:4 followed by solvent fraction. The supernatant was collected from the solvent fraction, and polyphenols precipitate was taken out, powdered and stored. The water was retrieved from the extraction process.

Example 3: Analysis of extracted pectin

The pectin was taken for chemical parameter test and results are tabulated below.

Results: Comparing to the IPPA specification pectin standards, product was well within accepted specified limits of Nitrogen, Acid insoluble, lead, total heavy metals and Sulphur dioxide.

Example 4: HPLC characterization of phenolics of coffee pulp

The polyphenols were taken for HPLC characterization as shown in the figure 1 and figure 2, and results are tabulated below:

Results- The Coumaric acid content obtained is and the above ranges indicating its therapeutic and cosmetic properties such as antioxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti- melanogenic properties and reduces oxidative stress.

Example 5: Characters of coffee pectin considered as low methoxy pectin

The pectin was taken for chemical parameter test and results are tabulated below.

Example 6: Biological Oxygen Demand (BOD) analysis

The retrieved water was taken into BOD analysis and the results were found to be less than lOOOmg/L which are used for irrigation or other purposes directly.

While the disclosure has been presented with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the disclosure. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the disclosure.