Coffee Pulp Characterization and Utilization in Coffee Cherry Flour for Circular Economy Improvement

Damat Damat1, Roy Hendroko Setyobudi2, Shazma Anwar3, Mohammed Ali Wedyan4,

Zane Vincevica-Gaile5, Yogo Adhi Nugroho2, Tony Liwang2, Thontowi Djauhari Nur Subchi1*,

Ahmad Fauzi1, Hanif Alamudin Manshur1, Devi Dwi Siskawardani1, Vritta Amroini Wahyudi1,

Yolla Muvika Ananda1 and Hemalia Agustin Rachmawati1

1University of Muhammadiyah Malang, Malang 65144, East Java, Indonesia; 2Plant Production and Biotechnology Division, PT Smart Tbk., Bogor 16810, West Java, Indonesia; 3University of Agriculture, Peshawar 25130, Khyber Pakhtunkhwa, Pakistan; 4The Hashemite University, PO Box 330127, 13133 Zarqa, Jordan; 5University of Latvia, Riga LV-1004, Latvia.

Received | June 08, 2024; Accepted | July 01, 2024; Published | September 02, 2024

*Correspondence | Thontowi Djauhari Nur Subchi, Department of Anatomy, Faculty of Medicine, University of Muhammadiyah Malang, Jl. Bendungan Sutami No.188, Malang 65145, East Java, Indonesia; Email: thontowidjauhari448@gmail.com

Citation | Damat, D., R.H. Setyobudi, S. Anwar, M.A. Wedyan, Z. Vincevica-Gaile, Y.A. Nugroho, T. Liwang, T.D.N. Subchi, A. Fauzi, H.A. Manshur, D.D. Siskawardani, V.A. Wahyudi, Y.M. Ananda and H.A. Rachmawati. 2024. Coffee pulp characterization and utilization in coffee cherry flour for circular economy improvement. Sarhad Journal of Agriculture, 39 (Special issue 1): 71-83.

DOI | https://dx.doi.org/10.17582/journal.sja/2023/39/s1.71.83

Keywords | Biowaste utilization, Coffea arabica L., Coffee byproducts, Environmentally friendly Biowaste management, Functional food ingredients

Copyright: 2024 by the authors. Licensee ResearchersLinks Ltd, England, UK.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

Introduction

Coffee has become an essential food-and-beverage commodity with high trade volume worldwide. Indonesia is recorded as the fourth largest coffee producer in the world (Apriani et al., 2022; Mussatto et al., 2011), and its production is dominated by local small business holders (Campera et al., 2021; Wulandari et al., 2022). Since its introduction by the Dutch colonialists in the late 18th century (Sera and Oktaviyani, 2022; ten Brink, 2017), coffee has been widely spread and cultivated on various islands for decades (Boer et al, 2020; Neilson et al., 2018). Quite many coffee specialties, ones with distinctive flavors and unique characteristics that gain them higher market values, are raised in specific locations in Indonesia – among them are Arabica Gayo, Flores Bajawa, Java Ijen-Raung, Kintamani, Mandailing, and Toraja.

While the annual increase in global demand boosts coffee production, poorly man-aged waste from coffee processing results in water and land pollution (Genanaw et al., 2021; Pandey et al., 2000; Setyobudi et al., 2021a). Coffee husk and pulp (CH and CP, respectively) – representing 40 % to 50 % of fresh coffee cherry weight – dominate as waste products and are still poorly utilized (Duran-Aranguren et al., 2021; Oliveira et al., 2021). While essentially rich in sugars, proteins, minerals, fibers, and phenolic acids (Arya et al., 2022; Blinova et al., 2017; Marin-Tello et al., 2020; Setyobudi et al., 2021b), CP makes up a small percentage of the revenue in the coffee industry when treated as waste and therefore calls for a coffee byproduct development scheme into a new source of revenue and, at the same time, a means to contribute to the sustainability of the industry (Murthy and Naidu, 2012; Setyobudi et al., 2019). Some attempts have been made to address the issue by reusing and recycling CH and CP into feed (Estrada-Flores et al., 2021; Núñez et al., 2015), fertilizers (Dadi et al., 2019; Takala, 2021), fuel, i.e., briquettes (Setter and Oliveira, 2022; Tesfaye et al., 2022); biofuel (Martinez et al., 2021; Wondemagegnehu et al., 2022); biomass (Amertet et al., 2021; Rivera and Ortega-Jimenez, 2019), and biogas (Chala et al., 2018; Getachew et al., 2023).

Lachenmeier et al. (2022) stated that the side products above are at the base of the pyramid model for coffee-by-product application, while alimentary uses are at the top of the pyramid. Several experts (Ariva et al., 2020; Heeger et al., 2017; Muzaifa et al., 2021; Pua et al., 2021; Zeckel et al., 2019) reuse and recycle CP for beverages, i.e., cascara. Research on CH and CP to discover its nutrients, bioactive compounds, and mineral and food fiber contents has been carried out (Cubero-Castillo et al., 2017; Damat et al., 2019; Damat et al., 2023; Marin-Tello et al., 2020; Mindarti et al., 2020; Moreno et al., 2019; Rosas-Sánchez et al., 2021). However, only a few discuss its potential as coffee cherry flour (CCF), particularly due to its high Fe non-heme content, which is valuable for anemia treatment (Marin-Tello et al., 2020; Setyobudi et al., 2019, 2021a, 2021b, 2022, 2023). Fe non-heme for hemoglobin booster is essential due to the relatively high chance of anemia (Milman, 2011; Muhammadong et al., 2021), yet oral Fe supplementation has a number of negative impacts (Bloor et al., 2021; Lukito and Wahlqvist, 2020; Nadiyah et al., 2020).

Aiming that the application of coffee byproducts is expected to reduce environmental pollution, provide alternative products, and produce economically valuable compounds (Arya et al., 2022; Blinova et al., 2017; Duran-Aranguren et al., 2021; Marin-Tello et al., 2020; Murthy and Naidu, 2012; Oliveira et al., 2021; Pandey et al., 2000; Setyobudi et al., 2019, 2021a, 2021b, 2022, 2023), a study was conducted at three traditional farms in Indonesia – Ijen, Karangploso, and Mengani – specifically producing Arabica coffee (Coffea arabica L.) to reuse and recycle CP waste into CCF. However, each source should have indigenous CP properties considering their unique edaphic and climatic factors, which may affect the resulting CCF’s nutritional values. Therefore, it is essential to analyze the nutrients in each CP sample and select the most suitable one for CCF as a functional food production. It is significant to examine mineral, heavy metal, proximal, dietary fiber, and sugar contents and to compare values to commercially available CCF to meet the standard.

Since previous studies were generally concentrated on a selection of coffee varieties or samples of certain coffee plantations, further explorations on different variants and places are relevant to extrapolation (Ariva et al., 2020; Arya et al., 2022; Blinova et al., 2017; Duran-Aranguren et al., 2021; Estrada-Flores et al., 2021; Heeger et al., 2017; Marin-Tello et al., 2020; Murthy and Naidu, 2012; Mussatto et al., 2011; Muzaifa et al., 2021; Núñez et al., 2015; Oliveira et al., 2021; Pandey et al., 2000; Pua et al., 2021; Zeckel et al., 2019). Another reason is the limited sources of CP bioactive compounds specifically gained in Ijen, Karangploso, and Mengani. This study is projected to complement the information on nutrient contents and bioactive compounds in CP of Indonesian coffee and emphasize the prospect of CP for CCF production as a means for achieving a biobased circular economy where coffee waste supports sustainability and also contributes to local income.

Materials and Methods

Sample collection

Coffea arabica L. byproduct samples were collected from three organic traditional farms located in Indonesia – Ijen Farm in Bondowoso, East Java (7°57’59.55” S; 114°01’14.37” E), Karangploso Farm in Malang, East Java (7°52’13.80” S; 112°34’54.44” E), and Mengani Farm in Mengani, Bali (8°17’16.63” S; 115°15’0.61” E). At each location, the sample collection was performed during 2 wk taking a random sample every day; thus, the total collected amount of coffee byproduct samples was about 15 kg. For the tests, three mixed samples were prepared and analyzed with three replications. All the samples were dried, resulting in strong differences regarding particle size (Figure 1A). The dried CP samples were homogeneously ground and sieved prior to analysis (Figure 1B, C, and D). La Boitê, a commercial CCF product made in Brazil, served as the control (Figure 1E).

 

Mineral assay

Employing an Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) (730-ES, Varian Inc., USA), macro-nutrients (N, P, K, Mg, Ca), micro-elements (Al, B, Co, Cu, Fe, Mn, Na, Ni, Zn, Cl), trace-elements (Ba, Ga, In, Li, Sr, Ti) and heavy metals (Cd, Cr, Pb, Hg) were simultaneously examined. A total of 5 g powdered CCF from each sample was run through dry-ashing procedures involving hydrochloric acid dilution to extract the minerals. Total N contents were specifically estimated using the Kjeldahl method (Aguirre, 2023; FOSS, 2003).

Proximate analysis

Following the standard methods (AOAC, 2010; Quadri et al., 2021), crude protein content was determined using the Kjeldahl System (Buchi, Switzerland). Crude lipid content was applied ether extraction in a Soxhlet extractor (SER 148, VELP Scientifica, Italy), and moisture content was determined after oven-drying (Memert UF55 plus, Germany) 105 °C for 6 h while ash content was measured following combustion at 550 °C for 4 h in a muffle furnace (1200C 64L, K type, China).

Amino acid analysis:

Acid hydrolysis with 6 N HCl (reflux for 23 h at 110 °C) was directed prior to the tests using an automatic amino acid analyzer (Hitachi, Japan) as described in detail by Qiu et al. (2016).

Sugar content analysis

Operating the Dubois method (DuBois et al., 1956; Yue et al., 2022) to determine the reducing and total sugar concentrations, each CCF sample was diluted up to 200 times before mixing with 100 µL of 5 % phenol. Once 5 mL of 98 % sulfuric acid was added, it was vortex-mixed and rested for 10 min. The absorbance was analyzed using a spectrophotometer at 490 nm. An HPLC (Shimadzu, Prominence UFLC- Nexera XR, Japan) equipped with a refractive index detector (Shimadzu, RID 10A, Japan).

Dietary fiber

Following the AOAC method (AOAC, 1995; McCleary et al., 2013), 0.5 g of each powdered ample was added with 0.1 mL alpha-amylase enzyme in an Erlenmeyer flask before being heated at 100 °C for 15 min involving occasional stirring. Once cooled,

20 mL distilled water and 5 mL HCL 1 N were added. 1 mL of 1 % pepsin enzyme was mixed in prior to a 1 h water bath heating (Thermostatic Water Bath SY-2L8H, China). Removed from the bath, 5 mL 1 N NaOH and 0.1 mL beta amylase enzyme went into the flask. Tightly capped, it was sent to 1 h water bath incubation. The sample was then strained using a Whatman filter No 42 (weighed before use), rinsed with 10 mL ethanol and 10 mL acetone, oven-dried (Memert, UN 55, Germany) at 105 °C for a night, desiccator cooled, and measured for Insoluble Dietary Fibers (IDF) determination. Next, the same filtrate was volume adjusted to 100 mL, mixed with 400 mL

warm 95 % ethanol, let sit for 1 h, strained using ash-free filter paper (weighed before use), rinsed with

10 mL ethanol and 10 mL acetone, oven dried at 105 °C for a night, desiccator cooled, and measured for Soluble Dietary Fibers (SDF) establishment. Dietary fiber is calculated as per Equation (1):

Total dietary fiber = Soluble dietary fiber + Insoluble dietary fiber.........(1)

All chemicals in this study are provided by pro analysics (p.a.).

Data recording and statistical analysis

Each sample assay was carried out in two replications to ensure accuracy, and the results were computed in SPSS-IBM Statistics – Version 29. Analysis of variance (ANOVA), followed by Tukey post-hoc (honestly significant difference - HSD) test, was run in order to verify sample differences where significance was set at P ≤ 0.05 and the results would be presented in mean values and standard error (SE) of the mean. Variables with significant differences were visualized in interval plot of 95 % confidence interval (Adinurani, 2016). Sample characteristics on particular parameters were based on principal component analysis (PCA) (Nasibeh, 2019). Cluster analysis with heatmap visualization based on library gplots of the R package was also involved (Tomanek and Schröder, 2018).

Results and Discussion

Essential nutrients sufficiently provided in dietary foods should cover major minerals (phosphorus, potassium, magnesium, calcium, sodium, and chloride) and trace elements (iron, zinc, selenium), and that is described further.

Mineral content analysis

Figure 2 regarding PCA result reveals clear separations of all analyzed samples and the control. While Ijen, Mengani, and La Boitê gather on the left of the axis, Karangploso is settled on the right. The fact that both Ijen and Mengani are close to each other on the upper part generally embodies their similarity regarding mineral contents. It also depicts how Fe content positively correlates to some micro-elements such as Al, Co, Mn, and Ni but is negatively associated with Zn and P. Some heavy metal contents are positively linked with minerals, i.e., Cr with Ca and Cd and Cr with Zn. Furthermore, the figure indicates that nearly 79 % of the variation of the model could be explained based on two aspects of principal components. First, a 50 % variation distinguishes Karangploso from other samples in most trace elements and heavy metals. Second, La Boitê has specific nutrient properties such as high K, Cl, and B contents.

The heatmap in Figure 2 shows how Mengani is the sample most parallel to La Boitê, with an addition on high P and Zn contents. Seeing how Zn is beneficial for food biofortification, this discovery supports Setyobudi et al. (2021b, 2022, 2023) recommending CCF as a functional food to deal with anemia. Yet, the color spread confirms Karangploso CCF and La Boitê to be close due to their color similarities. Ijen, on the other hand, is the most dissimilar of all.

 

Mineral content information should be beneficial in determining CP potentials. Take Karangploso, for example – as it is high in Fe and Ca, the iron should make it suitable for functional food. However, Setyobudi et al. (2022) doubt it to be its natural feature due to the possibility of rust residue from the pulper mixed in CP since the farm uses little amount of rinsing water. CP rich in N, Ca, and P generally fit for fertilizer application in agriculture (Setyobudi et al., 2019). Certain other nutrients make CP a good supplement for feed (Batbekh et al., 2023; Estrada-Flores et al., 2021; Núñez et al., 2015; Oropeza-Mariano et al., 2022; Venkatesh, 2022). Meanwhile, CP with low mineral content matches the requirement for bioethanol or other renewable energy (Amertet et al., 2021; Chala et al., 2018; Getachew et al., 2023; Martinez, et al., 2021; Rivera and Ortega-Jimenez, 2019; Setter and Oliveira, 2022; Tesfaye et al., 2022; Wondemagegnehu et al., 2022) as fermentation is involved (Azhar et al., 2017), and the correlation between mineral content and the process is yet to be empirically proven.

Focusing on CCF production, a number of considerations are required. If it should be rich in minerals – particularly Co, Ti, Al, Cr, Ca, Fe, In, Mn, Na, and Mg – Karangploso CP is the option. However, mineral balance is also pertinent as micronutrient and macronutrient contents define CCF quality and, as a result, enhance the product’s market value. While micronutrients like Fe, Zn, and Cu are favorable in metabolism (Lu et al., 2021; Shenkin, 2006), macronutrients like protein, carbohydrate, and food fiber are suitable for energy sources and body tissue restoration (Damat et al., 2019; Damat et al., 2023; Setyobudi et al., 2021b; Wu, 2016). If it should be the closest to existing commercial CCF, then Mengani is the recommended variant. This finding is in sync with Setyobudi et al. (2021b, 2022, 2024).

Heavy metal analysis

Certain heavy metals can be harmful when accumulated and deposited in the body, so their contents in raw materials must be carefully screened for human dietary food (Jairoun et al., 2020; Ramlan et al., 2022). This study has found no significant differences between the samples and the control in terms of Cr, Pb, and Hg contents (Table 1). The Hg contents were < 0.00006 mg kg–1 – below the detection limit – in all samples analyzed. The significant difference in potentially harmful metal content is only seen in Cd; however, Mengani – containing the lowest Cd rate of all samples – is not significantly different from La Boitê commercial product. This finding affirms the feasibility of Mengani CP being processed into CCF for human dietary intake.

Table 1 demonstrates a different finding from Avinash et al. (2017), testifying that Cd and Pb are not detected in CP. Another point is that heavy metal contents in Indonesian CP and La Boitê are higher – except for Pb – than in Bondesson’s study (Bondesson, 2015) based on dried CH samples gained from Honduras. Heavy metals contained in CP are generally in tiny quantities and are inconsequential. However, excessive amounts of Pb (Assi et al., 2016; Khoiroh et al., 2023; Prakash and Kashyap, 2023) and Cd (Godt et al., 2006; Tchounwou et al., 2012) in the system can cause physical detriment in some cases. Any disproportionate hazardous material indicates that CP is not viable for food or feed but acceptable for organic fertilizer.

It is noteworthy that, aside from Cd in the Ijen sample, heavy metal contents of the studied CP samples and La Boitê are all below the maximum limits regulated by Indonesia National Standard (SNI 7377-2009) (BSN, 2009) and Indonesian Drug and Food Control Agency (BPOM No. 9 2022) (BPOM, 2022).

Proximate analysis

Proximate composition indicates nutritional components in raw materials for human dietary food, and

 

Table 1: Heavy metal contents in the CCF samples from Ijen, Karangploso, and Mengani (mg kg–1).

Variables	Source				ANOVA
	Ijen farm	Kr. Ploso farm	Mengani farm	La Boitê	F value	p value
Cd	0.220 ± 0.130 a	0.030 ± 0.004 b	0.012 ± 0.005 c	0.017 ± 0.001 bc	1340.67	0.000**
Cr	0.609 ± 0.356	3.190 ± 1.200	0.747 ± 0.168	0.196 ± 0.015	2.60	0.165 ns
Pb	0.261 ± 0.095	0.867 ± 0.201	0.539 ± 0.093	0.854 ± 0.151	2.25	0.200 ns
Hg	< 0.00006	< 0.00006	< 0.00006	< 0.00006

 

The value expressed in the mean ± standard error of the mean. The mean value followed by the same letter in the row does not differ by the Tukey t student test at 5 % probability.

 

Table 2: Proximate analysis on CCF samples from Ijen, Karangploso, and Mengani (mg kg–1).

Parameter	Source				ANOVA
	Ijen farm	Kr. Ploso farm	Mengani farm	La Boitê	F value	p value
Dry matter	89.02 ± 0.01 c	89.92 ± 0.02 b	89.02 ± 0.01 c	92.92 ± 0.03 a	4 377.52	0.000 **
Organic matter	90.63 ± 0.02 b	89.47 ± 0.22 c	91.57 ± 0.09 a	72.23 ± 0.01 d	5 972.49	0.000 **
Crude protein	16.36 ± 0.24 ab	15.59 ± 0.12 b	16.03 ± 0.10 ab	16.56 ± 0.01 a	9.47	0.027 **
Crude fiber	29.13 ± 0.05 a	20.59 ± 0.26 b	18.48 ± 0.17 c	17.68 ± 0.21 c	789.83	0.000 **
Crude lipid	0.56 ± 0.01 c	2.11 ± 0.02 b	0.54 ± 0.01 c	3.03 ± 0.03 a	4 886.12	0.000 **

 

The value expressed in the mean ± standard error of the mean. The mean value followed by the same letter in the row does not differ by the Tukey t student test at 5 % probability.

 

one may differ from another depending on agro-climatic conditions, soil type, and agronomic practice. Table 2 illustrates how crude protein, crude fiber, and crude lipid contents (expressed on a dry weight basis) in all samples are significantly different. Specifically, the Mengani sample contains crude protein and crude fiber insignificantly different from the La Boitê commercial sample. It should prove that Mengani CP is a sufficient biomaterial for CCF production despite its low crude lipid content, as it is favorable in a low-fat diet (Table 2).

Further CP potentials can be derived from proximate analysis results. Dry matter corresponds to moisture content – CP is easier to process into CCF if its dry matter is not too low and moisture content is not too high. Maintaining ideal dry matter content is the main problem in CCF production, considering sun-drying CP on drying floors in farm areas of > 1 000 m asl where the sunlight is not as intense as in lower areas and the rainfall is high is less effective. Involving oven dryers – either electricity, LPG, or biogas-powered – should solve the issue, and the temperature should not be higher than 50 °C to preserve amino acid contents in CP (Setyobudi et al. 2021b, 2022, 2024).

Dietary fiber

Plant complex molecules are resistant to breakage in digestion, and dietary fibers help to avoid various diseases (BPOM, 2022; Gill et al., 2021). The fiber composition of insoluble dietary fibers (IDF) and soluble dietary fibers (SDF) is a significant variable in both food productions.

Referring to the heatmap in Figure 3, it is surmised that Mengani has the closest Total Dietary Fiber (TDF) to Ijen, while Karangploso is the farthest. Further, with a TDF of 54.5 % – consisting of 36.4 %

IDF and 18.1 % SDF – Mengani has only slightly lower food fibers than La Boitê, with 59.2 % TDF containing 41.1 % IDF and 18.1 % SDF. IDF prevents constipation and therefore promotes healthy intestine (Barber et al., 2020; Damat et al., 2019; Damat et al., 2023) by being indigestible and adding volume to feces, while SDF reduces cholesterol (Guan et al., 2023; Surampudi et al., 2016) and blood sugar (Giuntini et al., 2022; Nasiry et al., 2022) that often trigger cardiovascular problems (Chawla and Patil, 2010; Yang et al., 2017; Damat et al., 2019) by forming gel to trap excessive nutrients and take them out of the system with feces. Both fibers should be part of a healthy end-product like CCF.

As for feed production, acid-neutral fibers (ANF) and neutral detergent fibers (NDF) are vital. Fibers containing low cellulose, lignin, and hemicellulose typically take up less space in the stomach, allowing more feed intake and providing a larger amount of energy to animals Mengani CP contains 50.24 % NDF and 43.17 % ADF, affirming its practicability for feed.

Sugar content

The following key variable in the diet is sugar content. The bar graph in Figure 3 demonstrates that Mengani CCF contains a similar amount of sugar to the La Boitê commercial sample, while the Ijen sample has the least. Sugar serves as an energy source and owns its structural and functional properties, among them boosting Fe non-heme absorption as recommended by Setyobudi et al. (2021b) and (2022).

Fructose and glucose are two simple forms of sugar generally found in food. Their contents in CP affect the quality and characteristics of CCF products – the higher their rates are, the darker they will look and the sweeter they will taste. How much sugar is ideally contained in CCF depends on the purpose and market target.

 

Regarding CCF production, it is generally gathered that Mengani CP owns the best potential. This discovery is paramount in the context of environmentally friendly waste management and sustainable bioeconomy development. Transforming CP into CCF diminishes organic waste from the coffee industry and reduces pollution while also fostering additional revenue for coffee farmers and their stakeholders. Furthermore, it should promote a healthy lifestyle as CCF opens more access to nourishing food and beverages regarding fiber, protein, and iron. As heavy metals in CP may negatively impact health and the environment, safety measures in material selection and waste management should be of serious concern.

Conclusion and Recommendation

This study concludes that compared to the ones from Ijen and Karangploso, coffee pulp from Mengani farm in Bali is the best possibility for circular economy improvement by coffee byproduct processing into coffee cherry flour as its characteristics are the most similar to the currently available commercial product originated from Brazil. Mineral, heavy metal, crude protein, crude fiber, and sugar contents in the Mengani sample do not significantly differ from the La Boitê commercial sample. The only differences are that its dietary fiber content is faintly lower than for La Boitê, and its crude lipid content is significantly lower.

Acknowledgments

It is forwarded with deep regret that Yogo Adhi Nugroho, one of the authors of this article, passed away after a fight against COVID-19. The authors wish to extend their sincere appreciation for his enthusiasm and dedication to the writing process of this manuscript, especially concerning the statistical analysis. The authors would like to express their gratitude to Ricky Hendarto Setyobudi and Fitri Ramli (Arabica Coffee Factory at Mengani, Kintamani, Bali), Soni Sisbudi Harsono (University of Jember), and Pandu Prabowo (Kopi Carlos, Malang) for supplying the CCF research materials. The authors also wish to thank Yohannes Kohar Whisnu Wardhana for bringing CCF packages from La Boitê, a store at Manhattan, 724 11th Avenue, New York, NY 10019, USA, to Indonesia. Also, thanks to the Directorate of Research and Community Service, University of Muhammadiyah Malang (DPPM – UMM), which has funded this research with letter No. E.2a/811/BAA-UMM/viii/2023.

Novelty Statement

This study supports and complements previous studies (Setyobudi et al., 2019, 2021b, 2022, 2023) that Indonesian coffee pulp, especially from Kintamani, is suitable for use as a source of Coffee Cherry Flour (CCF). Concerns about the mineral content, primarily heavy metals, are also shown in this manuscript that CCF Kintamani - Bali is not higher than commercial CCF from Brazil.

Author’s Contribution

Damat Damat and Thontowi Djauhari Nur Subchi: supervision and funding

Roy Hendroko Setyobudi: conceptualization, methodology, resources, and writing – review & editing

Yogo Adhi Nugroho: formal analysis, writing – original draft preparation

Tony Liwang: heavy metal and mineral analysis

Ahmad Fauzi: writing – original draft preparation

Shazma Anwar, Zane Vincevica-Gaile, Mohammed Ali Wedyan and Hanif Alamudin Manshur: writing – review & editing

Vritta Amroini Wahyudi, and Devi Dwi Siskawardani: validation, software, and visualization

Yolla Muvika Ananda and Hemalia Agustin Rachmawati: proximate, amino acid, and sugar content analysis.

All authors have read and approved the final manuscript.

Conflict of interest

The authors have declared no conflict of interest.

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