Modeling the color evolution: insight into the browning pigmentation mechanism and bioactive compounds evaluation of coconut syrup production
-
Frederick Sarpong
,
Shadrack Donkor
Abstract
This study aims to better understand the color formation in coconut syrup production by modeling the dynamics of color evolution. Coconut sap was processed (105 ± 5 °C), with for samples intermittent analysis. Besides the modeling evaluation, bioactive compounds including total phenolic, flavonoid content and DPPH assay were also evaluated. The exponential model provided the greatest fit, with R2 values of 0.84903–0.9798, lowest Chi-square (χ2) values of 3.14 × 10−4–6.789, and root mean square error (RMSE) of 8.17305–0.1784. Heating time was found to correlate positively with both browning reactions, resulting in an increase of 15.16 and 2.44 folds in the enzymatic and non-enzymatic browning indexes, respectively. The second-order polynomials characterized the browning reactions more accurately than Weibull’s model. A rise in bioactive chemicals was detected at the conclusion of the processing period, which closely linked with a * and b * color and enzymatic browning reactions, demonstrating the nature of the reliance between them.
Acknowledgments
The authors thank the Council for Scientific and Industrial Research (CSIR) – Oil Palm Research Institute (OPRI) in Kade-Ghana for their technical assistance and provision of laboratory space and resources for the investigations.
-
Research ethics: Not applicable.
-
Informed consent: Not applicable.
-
Author contributions: FS: conceptualization, methodology, software, formal analysis, resources, data curation, drafted original manuscript, funding acquisition, project administration. SD: methodology, software, data curation, validation, investigation. CO-Y: methodology, validation, investigation, data curation, review, editing. EFB: validation, data curation, review, editing, investigation, software, visualization. JO-K: project administration, methodology, supervision, proofread, editing, resources.
-
Use of Large Language Models, AI and Machine Learning Tools: None.
-
Conflict of interest: None.
-
Research funding: No external funding was received for this study.
-
Data availability: Not applicable.
List of symbols
- a *
-
redness
- L *
-
lightness
- k; a; b
-
constants
- b *
-
yellowness
- SD
-
standard deviation
- χ2
-
reduced chi-square
- ΔE
-
total color difference
- TPC
-
total phenolic content
- RMSE
-
root means square error
- TFC
-
total flavonoids content
- R2
-
determination coefficient
- EBI
-
enzymatic browning index
- RSA
-
radical scavenging activity
- 2-FM-AA
-
2-furoylmethyl-amino acids
- DPPH
-
2,2-diphenyl-1-picrylhydrazyl
- PCA
-
principal component analysis
- NBI
-
non-enzymatic browning index
- CIELAB
-
commission international de l’eclairage’s lab
References
1. Nurhadi, B, Sukri, N, Saputra, RA, Wandhani, FI, Nurlita, AI. Physical characteristics of amorphous and crystalline coconut sugar powder with the addition of tricalcium phosphate (TCP) as an anticaking agent. Int J Food Sci 2020:1–10. https://doi.org/10.1155/2020/5320173.Suche in Google Scholar PubMed PubMed Central
2. Abdullah, WG, Rianse, U, Iswandi, RM, Taridala, SAA, Widayati, W, Rianse, IS, et al.. Potency of natural sweetener: brown sugar. Adv Environ Biol 2014;8:374–85.Suche in Google Scholar
3. Asghar, MT, Yusof, YA, Mokhtar, MN, Yaacob, ME, Ghazali, HM, Varith, J, et al.. Processing of coconut sap into sugar syrup using rotary evaporation, microwave, and open‐heat evaporation techniques. J Sci Food Agric 2020;100:4012–19. https://doi.org/10.1002/jsfa.10446.Suche in Google Scholar PubMed
4. Karseno, E, Yanto, T, Setyowati, R, Haryanti, P. Effect of pH and temperature on browning intensity of coconut sugar and its antioxidant activity. Food Res 2017;2:32–8. https://doi.org/10.26656/fr.2017.2-1-.175.Suche in Google Scholar
5. Sarpong, F, Jiang, H, Oteng-Darko, P, Zhou, C, Amenorfe, LP, Mustapha, AT, et al.. Mitigating effect of relative humidity (RH) on 2-furoylmethyl-amino acid formation. LWT 2019;101:551–8. https://doi.org/10.1016/j.lwt.2018.11.077.Suche in Google Scholar
6. Hebbar, KB, Arivalagan, M, Manikantan, MR, Mathew, AC, Thamban, C, Thomas, GV, et al.. Coconut inflorescence sap and its value addition as sugar – collection techniques, yield, properties and market perspective. Curr Sci 2015;109:1411. https://doi.org/10.18520/v109/i8/1411-1417.Suche in Google Scholar
7. Elik, A, Yanık, DK, Maskan, M, Göğüş, F. Influence of three different concentration techniques on evaporation rate, color and phenolics content of blueberry juice. J Food Sci Technol 2016;53:2389–95. https://doi.org/10.1007/s13197-016-2213-0.Suche in Google Scholar PubMed PubMed Central
8. Sarpong, F, Yu, X, Zhou, C, Hongpeng, Y, Uzoejinwa, BB, Bai, J, et al.. Influence of anti-browning agent pretreatment on drying kinetics, enzymes inactivation and other qualities of dried banana (Musa ssp.) under relative humidity-convective air dryer. J Food Meas Char 2018a;12:1229–41. https://doi.org/10.1007/s11694-018-9737-0.Suche in Google Scholar
9. Cernîşev, S. Effects of conventional and multistage drying processing on non-enzymatic browning in tomato. J Food Eng 2010;96:114–18. https://doi.org/10.1016/j.jfoodeng.2009.07.002.Suche in Google Scholar
10. Waterhouse, AL. Determination of total phenolics. Curr Protoc Food Anal Chem 2002;6:l1–1.10.1002/0471142913.fai0101s06Suche in Google Scholar
11. Ruangchakpet, A, Sajjaanantakul, T. Effect of browning on total phenolic, flavonoid content and antioxidant activity in Indian gooseberry (Phyllanthus emblica Linn.). Kasetsart J/Nat Sci 2007;337:331–7.Suche in Google Scholar
12. Alzagameem, A, Khaldi-Hansen, BE, Büchner, D, Larkins, M, Kamm, B, Witzleben, S, et al.. Lignocellulosic biomass as source for lignin-based environmentally benign antioxidants. Molecules 2018;23:2664. https://doi.org/10.3390/molecules23102664.Suche in Google Scholar PubMed PubMed Central
13. Sekhon, A, Dhillon, G, Mahajan, M, Singh, A, Kaur, K. Glycaemic index (GI) suppression of bread using polyphenols enriched karonda powder: a strategy to reduce starch digestibility and increase polyphenols retention. Int J Food Eng 2025;21:357–68. https://doi.org/10.1515/ijfe-2024-0161.Suche in Google Scholar
14. Aguiló-Aguayo, I, Gangopadhyay, N, Lyng, JG, Brunton, N, Rai, DK. Impact of pulsed light on colour, carotenoid, polyacetylene and sugar content of carrot slices. Innov Food Sci Emerg Technol 2017;42:49–55. https://doi.org/10.1016/j.ifset.2017.05.006.Suche in Google Scholar
15. Gupta, RK, Kumar, P, Sharma, A, Patil, RT. Color kinetics of aonla shreds with amalgamated blanching during drying. Int J Food Prop 2011;14:1232–40. https://doi.org/10.1080/10942911003637343.Suche in Google Scholar
16. Zielinska, M, Markowski, M. Color characteristics of carrots: effect of drying and rehydration. Int J Food Prop 2012;15:450–66. https://doi.org/10.1080/10942912.2010.489209.Suche in Google Scholar
17. Hossain, MA, Rahman, SMM. Total phenolics, flavonoids and antioxidant activity of tropical fruit pineapple. Food Res Int 2011;44:672–6. https://doi.org/10.1016/j.foodres.2010.11.036.Suche in Google Scholar
18. Mondal, MHT, Akhtaruzzaman, M, Sarker, MSH. Modeling of dehydration and color degradation kinetics of maize grain for mixed flow dryer. J Agric Food Res 2022;9:100359. https://doi.org/10.1016/j.jafr.2022.100359.Suche in Google Scholar
19. Prabhakar, H, Bock, CH, Kerr, WL, Kong, F. Pecan color change during storage: kinetics and modeling of the processes. Curr Res Food Sci 2022;5:261–71. https://doi.org/10.1016/j.crfs.2022.01.015.Suche in Google Scholar PubMed PubMed Central
20. Demiray, E, Tulek, Y. Color degradation kinetics of carrot (Daucus carota L.) slices during hot air drying. J Food Process Preserv 2015;39:800–5. https://doi.org/10.1111/jfpp.12290.Suche in Google Scholar
21. Chutintrasri, B, Noomhorm, A. Color degradation kinetics of pineapple puree during thermal processing. LWT--Food Sci Technol 2007;40:300–6. https://doi.org/10.1016/j.lwt.2005.11.003.Suche in Google Scholar
22. Arshad, RN, Buntat, ZB, Dastgheib, AM, Jusoh, YM, Munir, A, Aadil, RM, et al.. Continuous flow treatment chamber for liquid food processing through pulsed electric field. J Comput Theor Nanosci 2020;17:1492–8. https://doi.org/10.1166/jctn.2020.8829.Suche in Google Scholar
23. Topuz, A. A novel approach for color degradation kinetics of paprika as a function of water activity. LWT--Food Sci Technol 2008;41:1672–7. https://doi.org/10.1016/j.lwt.2007.10.004.Suche in Google Scholar
24. Zepka, LQ, Borsarelli, CD, da Silva, MAAP, Mercadante, AZ. Thermal degradation kinetics of carotenoids in a cashew apple juice model and its impact on the system color. J Agric Food Chem 2009;57:7841–5. https://doi.org/10.1021/jf900558a.Suche in Google Scholar PubMed
25. Sarpong, F, Oteng‐Darko, P, Golly, MK, Amenorfe, LP, Rashid, MT, Zhou, C. Comparative study of enzymes inactivation and browning pigmentation of apple (Malus domestica) slices by selected gums during low temperature storage. J Food Biochem 2018b;42:e12681. https://doi.org/10.1111/jfbc.12681.Suche in Google Scholar
26. Roobab, U, Abida, A, Afzal, R, Madni, GM, Zeng, XA, Rahaman, A, et al.. Impact of high-pressure treatments on enzyme activity of fruit-based beverages: an overview. Int J Food Sci Technol 2022;57:801–15. https://doi.org/10.1111/ijfs.15492.Suche in Google Scholar
27. Lyu, J, Liu, X, Bi, J, Wu, X, Zhou, L, Ruan, W, et al.. Kinetic modelling of non-enzymatic browning and changes of physio-chemical parameters of peach juice during storage. J Food Sci Technol 2018;55:1003–9. https://doi.org/10.1007/s13197-017-3013-x.Suche in Google Scholar PubMed PubMed Central
28. Burdurlu, SH, Karadeniz, F. Effect of storage on nonenzymatic browning of apple juice concentrates. Food Chem 2003;80:91–7.10.1016/S0308-8146(02)00245-5Suche in Google Scholar
29. Quevedo, R, Rojas, R, Pedreschi, F, Bastias, JM, Siché, R, Uquiche, E, et al.. Quantification of the browning kinetic on pita bread using fractal method. Food Bioprocess Technol 2018;11:201–8. https://doi.org/10.1007/s11947-017-2006-0.Suche in Google Scholar
30. Sarpong, F, Setorglo, J, Owusu-Kwarteng, J, Adams, B, Amenorfe, LP. Guar gum and sodium chloride coating delays chlorophyll degradation in okra during storage at 25 oC. Int J Veg Sci 2021a;27:198–208. https://doi.org/10.1080/19315260.2020.1759173.Suche in Google Scholar
31. Plaza, L, Crespo, I, de Pascual-Teresa, S, de Ancos, B, Sánchez-Moreno, C, Muñoz, M, et al.. Impact of minimal processing on orange bioactive compounds during refrigerated storage. Food Chem 2011;124:646–51.10.1016/j.foodchem.2010.06.089Suche in Google Scholar
32. Mehaya, FM, Mohammad, AA. Thermostability of bioactive compounds during roasting process of coffee beans. Heliyon 2020;6:e05508. https://doi.org/10.1016/j.heliyon.2020.e05508.Suche in Google Scholar PubMed PubMed Central
33. Bakir, S. The antioxidant activity of grapes after different drying treatments. Int J Food Eng 2025;21:437–46. https://doi.org/10.1515/ijfe-2024-0043.Suche in Google Scholar
34. Jati, IRA, Darmoatmodjo, LM, Suseno, TI, Ristiarini, S, Wibowo, C. Effect of processing on bioactive compounds, antioxidant activity, physicochemical, and sensory properties of orange sweet potato, red rice, and their application for flake products. Plants 2022;11:440. https://doi.org/10.3390/plants11030440.Suche in Google Scholar PubMed PubMed Central
35. Sarpong, F, Rashid, MT, Wahia, H, Aly, TAGA, Zhou, C. Mitigation of relative humidity (RH) on phytochemicals and functional groups of dried pineapple (Ananas comosus) slices. Int J Food Eng 2021b;17:265–74. https://doi.org/10.1515/ijfe-2020-0190.Suche in Google Scholar
36. Bastian, F, Hutabarat, OS, Dirpan, A, Nainu, F, Harapan, H, Emran, TB, et al.. From plantation to cup: changes in bioactive compounds during coffee processing. Foods 2021;10:2827. https://doi.org/10.3390/foods10112827.Suche in Google Scholar PubMed PubMed Central
37. Şimşek, A, Meraba, E, Turan, E. Effect of pomegranate (Punica granatum L.) peel and green coffee bean (Coffea arabica) extracts and their formulations on the oxidative stability of raw walnut oil under accelerated oxidation conditions. Int J Food Eng 2025;21:217–33. https://doi.org/10.1515/ijfe-2024-0206.Suche in Google Scholar
38. Kaiser, HF. The application of electronic computers to factor analysis. Educ Psychol Meas 1960;20:141–51. https://doi.org/10.1177/001316446002000116.Suche in Google Scholar
© 2025 Walter de Gruyter GmbH, Berlin/Boston
