Coffee melanoidin composition for mitigating emission of harmful gasses

Abstract

The present disclosure is directed to compositions for mitigating emissions of harmful gasses such as greenhouse gasses and methods using said compositions. More particularly the composition helps mitigating emissions of methane, hydrogen sulfide and ammonia. Said composition comprises melanoidin extracted from roasted coffee, preferably from spent coffee grounds.

Description

[0001] COFFEE MELANOIDIN COMPOSITION FOR MITIGATING EMISSION OF HARMFUL GASSES

[0002] Field

[0003] The present disclosure is directed to compositions for mitigating emissions of harmful gasses such as greenhouse gasses and methods using said compositions . More particularly the composition helps mitigating emissions of methane , hydrogen sul fide and ammonia .

[0004] Background

[0005] Humic substances constitute a highly trans formed fraction of natural organic matter with a heterogeneous structure . Water-soluble humic substances are generally referred to as humic acids and fulvic acids . Humic acids are random polycondensates with polyelectrolyte / polyampholite behaviour with a polyphenol or quinone-based aromatic core , in which functional side structures contain carboxylic, phenolic, and carbonyl groups , as well as sugar, peptide fragments . The subentities are connected by various connectors , such as -0- , - CH2- , =CH- , -NH- , -S-S- , and similar groups . The contained chemical functionality determines its properties in ion exchange , water absorption, its dispersion and cohesion energy, as well as interactions and complexation .

[0006] Because of these features , humic acids display a versatile reactivity with diversity of environmentally relevant processes . It was found that humic acids and more speci fically their redox-reactive molecules play an important role in controlling the emission of three of the most relevant greenhouse gasses due to their tight relationship with microbial activity, their abundance on the earth' s atmosphere and their global warming potentials : Carbon dioxide , methane and nitrous oxide .

[0007] However, the formation of humic substances under natural conditions requires many years and involves biotic and abiotic reactions . Therefore , several attempts have been made to prepare humic acid substances arti ficially . See Arti ficial Humic Acids : Sustainable Materials against Climate Change Yang F, Antonietti M, Adv . Sci . Lett . , 2020 .

[0008] Beside being ubiquitous in food stuf fs , melanoidins have long been believed to be amongst the building blocks of humic substances . Like humic and fulvic acids melanoidins exert a partially anionic character in aqueous solution over a wide pH range . To this end several attempts were made to synthetically prepare melanoidins . However, these types of synthetically prepared melanoidins do not have the high amounts of phenol- based compounds nor the quinonebased compounds that are considered to attribute to the positive properties of humic acid with respect to methanogensis suppression and hydrogen sul fide .

[0009] We have found that melanoidin extracts from roasted cof fee have a very high resemblance in the chemical structures and physico-chemical properties of humic acids . More particularly, melanoidin extracts from roasted cof fee were found to have excellent properties with respect to reduction of harmful gasses ' emissions .

[0010] Summary

[0011] The present disclosure provides a composition for mitigating the emission of harmful gasses such as methane , hydrogen sul fide and ammonia . Said composition comprises melanoidin extracted from roasted cof fee , preferably from spent cof fee grounds .

[0012] The melanoidins may be molecular weight (Mw) fractions of melanoidin extracted from spent cof fee grounds . The molecular weight (Mw) of the melanoidin fraction is preferably above 5 kDa, more preferably ranging from 10 kDa to 500 kDa, and most preferably between 50 to 200 kDa .

[0013] Preferably the melanoidin is obtained by alkaline extraction from spent cof fee grounds , more preferably by extraction with potassium hydroxide . Optionally the extraction is assisted by ultrasonic treatment

[0014] Especially preferred are melanoidins with a phenolics content of at least 3 wt% , more preferably ranging from 3- 30 wt . % of the total melanoidin, most preferably from 5-20 wt . % , calculated as tyrosol equivalents .

[0015] The melanoidin may be present in the composition in liquid or solid particulate form . The melanoidin may also be present in the composition as a salt such as its sodium, potassium, or ammonium salt .

[0016] The melanoidin may be present in a concentration of between 0 . 01-5% wt% of the total composition .

[0017] The melanoidin may also be present in the composition on a carrier in solid particulate form .

[0018] The composition may be used to mitigate harmful gasses in wetlands , (polluted) soil , but also in manure or even in cattle feed . The composition according to the invention may additionally comprise other constituents that are conventionally present in compositions for the speci fic applications described below .

[0019] The composition according to the present disclosure may suitably be used for the treatment of wetlands such as rice paddies , swamps etcetera, but also dry land . The composition was found to also be highly suitable for mitigating harmful gasses in manure and for mitigating emissions of enteric gasses in cattle .

[0020] Detailed Description

[0021] The present disclosure provides a composition for mitigating the emission of harmful gasses comprising melanoidin extracted from roasted cof fee , preferably from spent cof fee grounds .

[0022] As explained above , it was found that melanoidins extracted from roasted cof fee have a have a very high resemblance in the chemical structures and physico-chemical properties of humic acids .

[0023] Preferably the melanoidin is a molecular weight (Mw) fraction of melanoidin extracted from spent cof fee grounds . The molecular weight (Mw) of the melanoidin fraction is preferably above 5 kDa, more preferably ranging from 10 KDa to 500 KDa, and most preferably between 50 to 200 KDa .

[0024] It is found that the lower molecular weight compounds extracted from spent cof fee grounds , such as caf feine is toxic and may negate the positive ef fect of the higher molecular weight fractions on the mitigation of harmful gasses ' emissions . For instance , when using the melanoidin in feed, the higher molecular weight fractions are thought to provide an improved gut health in addition to mitigate emissions of harmful enteric gasses from cattle . When using the higher fraction melanoidin for treating land or soil , it is thought to have a beneficial ef fect on the growth and strength of crops as well .

[0025] A further advantage of using spent cof fee grounds is that this material which has been considered waste material in the past is now upcycled to a useful material which poses no threat to human' s or animals ' s safety and the environment and in fact makes improvements to those aspects .

[0026] The extraction of melanoidin from spent cof fee grounds is known from for instance WO 2022 / 268898 and 2012 / 130349 which have been incorporated by reference for this purpose .

[0027] Preferably the melanoidin is obtained by alkaline extraction from spent cof fee grounds . It was found that alkaline extraction ensures high yields of melanoidin without destroying the various useful compounds present in roasted cof fee . Suitable compounds used for alkaline extraction are NaOH and KOH with potassium hydroxide being preferred . Generally the extraction can be performed at a temperature between 100 and 140 ° C and a pressure of between 1 and 8 bar .

[0028] It was found that ultrasonic treatment assisted in the extraction by creating increased melanoidin yield with higher phenolic and quinone content . Without wishing to be bound to any theory it is thought that the ultrasonic mechanism for the fragmentation of cof fee and melanoidins particles partition occurs under ultrasound in two ways , pitting of the defatted cof fee grounds surface to produce fines and crack formations , which are further widened and deepened upon prolonged ultrasound exposure , releasing the melanoidins and assisting the formation of phenolic structures within the melanoidin polymers .

[0029] The ultrasonic treatment may be conducted at increased temperature of between 20- 100 ° C .

[0030] A lot of humic acids positive properties are attributed to the presence of phenolics and the nitrogen containing species . These compounds are thought to provide the Reduction / Oxidation capacity of humic acid . The melanoidins according to the disclosure was found to have high concentrations of phenolic compounds . Especially preferred are the melanoidins having a phenolics content of at least 3 wt% , more preferably ranging from 3-30 wt% of the total melanoidin, most preferable from 5-20 wt . % , calculated as tyrosol equivalents .

[0031] Owing to this high amount of phenolic compounds the composition according to the disclosure is found to mitigate the emissions of harmful gasses such as methane , ammonia and hydrogen sul fide .

[0032] The melanoidin according to the disclosure was also found to have a relatively high amount of quinone , which is also attributed to the redox capacities of humic acid and thus the ability to mitigate the emission of harmful gasses .

[0033] The composition according to the disclosure may be used as a liquid or solids composition . The melanoidin present therein may also be in liquid or solid particulate form depending on the application . When used in particulate form the particle si ze may vary from nano si ze ( i . e . under 1 micrometer ) to 250 micrometers .

[0034] The composition may comprise additional constituents that are conventionally present in (wet ) land or soil improvement compositions . For example surfactants , solvents , additional minerals , may be added to the composition . Especially the presence of mannan oligosaccharides is a preferred additional constituent since it is reported to have antifungal , anti-nematode , and anti-bacterial activity and is also retrievable from spent cof fee grounds .

[0035] The present disclosure is also directed to a method for mitigating the emission of harmful gasses wherein wetlands , soil , and / or manure is treated with the composition according to the disclosure . In this method the composition may comprise additional constituents that are conventionally present in (wet ) land or soil improvement compositions . For example surfactants , solvents , additional minerals , may be added to the composition .

[0036] When it is desired to treat soil with a particulate composition, the melanoidin may also be present in the composition on a carrier . This carrier preferably is inert and releases the melanoidin controlled over time . These types of carriers are known in the art and need no further elucidation here .

[0037] The present disclosure is also directed to a method to mitigate emissions of harmful enteric gasses from cattle , wherein the composition is administered to cattle .

[0038] Optionally, the composition is combined with conventional feed constituents for administration, but it may also be administered via the drinking water . Especially the presence of mannan oligosaccharides (MOS) is a preferred additional constituent since it may contribute to the gut health of the cattle and is also retrievable from spent coffee grounds.

[0039] It was found that the melanoidin composition is highly effective for mitigating emissions of enteric gasses in cattle and may be present in a concentration of between 0.01-5 wt% of the total composition.

[0040] The present disclosure is further elucidated by an example which merely serves for illustrative purposes and cannot be considered to restrict the present disclosure.

[0041] EXAMPLE

[0042] Liquid compositions containing a melanoidin extract obtained from alkaline extraction of spent coffee grounds of varying concentrations (0.01, 0.1 and 1 wt%, composition 1, 2, and 3 respectively) were prepared. The phenolics content was measured with the Folin-Ciocalteau assay as described in J. Agric. Food. Chem. 2010. 58 (14) , pp 81398144. The melanoidin had a phenolic content of 4 wt%, calculated a tyrosol equivalents.

[0043] Bottles of ruminal fluid were incubated with the compositions and standard diet for 96 hours.

[0044] • Two incubation batches were conducted for each concentration level of the compositions evaluated. Each batch included control bottles and blank treatment bottles (without diet or additive) .

[0045] • Triplicates were made for each concentration level of composition to achieve statistical power. • Serial measurements were taken at 6 and 24 hours of incubation to quanti fy the total gas production curve and its methane concentration .

[0046] • The study aimed to evaluate the ef fectiveness of the composition according to the disclosure in achieving methane and ammonia reductions .

[0047] • Three additional bottles for each concentration level of composition, as well as control and blank bottles , were incubated for 24 hours . After this period, the incubation ended, and the concentration of ammonia (NH3 ) in the incubation fluid was determined .

[0048] The number of samples generated were as follows :

[0049] • ( 3 Concentrations of composition x 2 hours x 3 repetitions x 2 batches ) + ( 1 Control x 2 hours x 3 repetitions x 2 batches ) + ( 1 blank x 2 hours x 3 repetitions x 2 batches ) = 84 samples

[0050] The results of the methane measurements are given in TABLE 1 below and the results for the ammonia measurements are compiled in TABLE 2 . The blank refers to incubation without any additive or diet . The average reduction is calculated relative to the control and the amount of methane gas is given in ppm . Table 1 : Methane concentration (ppm) at 6 and 24 hours of incubation

[0051] Table 2 : Ammonia concentration (ppm) at 6 and 24 hours of incubation

Claims

CLAIMS1 . Composition for mitigating the emission of harmful gasses comprising melanoidin extracted from roasted cof fee , preferably from spent cof fee grounds .2 . Composition according to claim 1 wherein the melanoidin is a molecular weight (Mw) fraction of melanoidin extracted from spent cof fee grounds .3 . Composition according to any one of the preceding claims wherein the molecular weight (Mw) of the melanoidin fraction is preferably above 10 kDa, more preferably ranging from 5 kDa to 500 kDa, and most preferably between 50 to 200 kDa .4 . Composition according to any one of the preceding claims wherein the melanoidin is obtained by alkaline extraction from spent cof fee grounds .5 . Composition according to any one of the preceding claims wherein the extraction is assisted by ultrasonic treatment6 . Composition according to any one of the preceding claims wherein the melanoidins have a phenolics content of at least 3 wt% , more preferably ranging from 3-30 wt% of the total melanoidin, most preferably ranging from 5-20 wt . % , calculated as tyrosol equivalents .7 . Composition according to any one of the preceding claims wherein melanoidin is present in the composition in liquid or solid particulate form .8 . Composition according to any one of the preceding claims wherein the melanoidin is present in a concentration of between 0 . 01-5% wt% of the total composition .9 . Composition according to any one of the preceding claims wherein the melanoidin is present in the composition on a carrier in solid particulate form .10 . Composition according to any one of the preceding claims wherein the composition comprises mannan oligo saccharide (MOS ) .11 . Method for mitigating the emission of harmful gasses wherein wetlands , soil , and / or manure is treated with the composition according to any one of the preceding claims .12 . Method according to claim 10 , wherein the composition comprises additional constituents that are conventionally present in land or soil improvement compositions .13 . Method to mitigate harmful enteric gasses from cattle , wherein the composition according to any one of the preceding claims 1- 10 is administered to cattle .14 . The composition according to claim 12 , wherein the composition is combined with conventional feed constituents for administration .

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