Subscribe Now Subscribe Today
Research Article

Effect of Natural Colorants on Color and Antioxidant Activity of "Kolang Kaling" (Sugar Palm Fruit) Jam

Rina Yenrina, Kesuma Sayuti and Tuty Anggraini
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Background: The colors of Asian melastome fruit, Java plum rind and Mangosteen rind range from red to dark purple. These fruits are also rich in anthocyanins, making them useful as natural colorants. Materials and Methods: In this study, it was evaluated that the color and antioxidant activity of jams produced with different concentrations of juice extracted from these fruits. The juice extracts were added at concentrations of 6, 8, 10 and 12% during the production of sugar palm fruit jam. Results: Analysis of sugar palm fruit jam with added juice from Asian melastome fruits, Java plum rinds and Mangosteen rinds produced colors with 0hue values of 6.90-14.00, 1.43-12.87 and 20.97-32.33, respectively and anthocyanin levels of 3.50-8.57, 3.28-11.19 and 1.61-3.73 mg L–1, respectively, the total phenol levels of 1.20-1.60, 1.32-1.94 and 0.83-3.51%, respectively. The antioxidant activity for each treatment exceeded 5,000 ppm, indicating a lack of activity. Conclusion: These results show that the addition of different amounts of natural colorants significantly affected the color of sugar palm fruit jam, as well as the total phenol and anthocyanin levels but did not improve antioxidant activity.

Related Articles in ASCI
Similar Articles in this Journal
Search in Google Scholar
View Citation
Report Citation

  How to cite this article:

Rina Yenrina, Kesuma Sayuti and Tuty Anggraini, 2016. Effect of Natural Colorants on Color and Antioxidant Activity of "Kolang Kaling" (Sugar Palm Fruit) Jam. Pakistan Journal of Nutrition, 15: 1061-1066.

DOI: 10.3923/pjn.2016.1061.1066

Received: October 03, 2016; Accepted: November 02, 2016; Published: November 15, 2016


Sugar palm fruit contains the polysaccharide galactomannan1. The main advantage of galactomannan over other polysaccharides is its ability to form highly viscous solutions at low concentration. Galactomannans are not significantly affected by pH, ionic strength or heating2. Galactomannan solutions maintain constant viscosities over a pH range of 1-10.5, which is likely due to the neutral charge of this molecule. Galactomannan is degraded only under very acidic or alkaline conditions or at high temperatures3.

Galactomannan can also act as an antioxidant. Boual et al.4 showed that a galactomannan-rich water-soluble polysaccharide mixture had antioxidant activity with an IC50 of 330 μg mL–1, which exceeds the <500 pg mL–1 IC50 value that is commonly thought to define antioxidant potential. Because of its contribution to viscosity and antioxidant properties, galactomannan from sugar palm fruit is often used as a raw material for jam production. Jam from sugar palm fruit is colorless, so natural colorants, such as those contained in Asian melastome fruit or rinds from Java plums or mangosteens are often added during jam production.

The purple color of Asian melastome (Melastoma malabathricum, L.) fruit is due to its flavonoid content. Anthocyanins are stable across a temperature range5 of 30-100°C. Between pH 1-3 and 5-9, anthocyanins are red and light blue-purple, respectively.

Anthocyanins extracted from Musa acuminata bracts are quite resistant to changes in pH (5.1 and 6.0) and temperature (20 and 30°C) both in the presence and absence of light6. Meanwhile, sorghum rich in 3-deoxyanthocyanins has a yellow to orange color in acidic media. Sorghum bran also has a high content of anthocyanins that have characteristics that are similar to those from other plants7.

However, increased temperature can decrease the total anthocyanin content in foods. For instance, during Java plum powder production, increased drying temperature and periods decrease the total anthocyanin content and the colors brighten8. Anthocyanin content in foodstuffs can be preserved by using a processing temperature below 60°C9. In addition to anthocyanins, fruits contain other bioactive compounds, including xanthones, prenylated derivatives and procyanidin10,11.

In this study, we examined how natural colorants derived from Asian melastome, Java plums and Mangosteens can affect the color and antioxidant activity in sugar palm fruit jam.


Materials: The main materials in this study are sugar palm fruit and natural colorants from Asian melastome fruit, Java plum rind and Mangosteen rind.

Design: The experimental design of this study involved 3 factors (3 natural colorants) and 4 different concentrations. Statistical analysis of data was performed using analysis of variance (ANOVA) and continued by Duncan’s New Multiple Range Test (DNMRT) at 5% significant level. The colorant concentrations were 6, 8, 10 and 12% (w/w).

Sugar palm fruit jam production: Sugar palm fruit jam was made by mixing sugar palm fruit pulp and sugar at a ratio of 45:55 (w:w) and adding fruit extracts at increasing concentrations. Natural colorants were prepared as slurries by adding water at a ratio of 1:3 (fruit:water) for Asian melastome fruit and Mangosteen rind and 1:1 for Java plum rind.

Sugar palm fruit jam characterization: To assess the resulting sugar palm fruit jam, color tests were performed according to the Hunter lab system12. Total anthocyanin content was determined using the pH differential method13. Total phenol content was assessed using the Folin-Ciocalteu method14 and antioxidant activity was determined by measuring absorbance of 2,2-diphenyl-1-picryhydrazyl (DPPH) at 517 nm15.


Raw materials: The total phenol and anthocyanin contents, as well as antioxidant activity of Asian melastome fruit juice and juice extracted from Java plum and Mangosteen rinds were assessed before use in jam production (Table 1).

The total phenol content in Asian melastome fruit juice was higher relative to juice extracted from Java plum and Mangosteen rinds (Table 1). Meanwhile, Java plum rind extracts had the highest total anthocyanin content (Table 1), which was expected given that Java plum rind juice was obtained from a 1:1 juice:water mixture, whereas Asian melastome fruit and Mangosteen rind juice was a 1:3 juice:water mixture.

Table 1:
Chemical contents and antioxidant activity of Asian melastome fruit juice and juice extracted from Java plum and Mangosteen rinds
Numbers are the Mean±SD

Table 2:Color of sugar palm fruit jam with additives
Numbers are the Mean±SD, means within the same column having different superscripted letters showed a significant difference (p<0.05) by Duncan’s New Multiple Range Test (DNMRT), L*: Value of dark and light colors. Low L* values (0-50) indicate darker color and L* >50 indicates bright colors, a*: Represents red and green. Positive and negative values indicate red and green, respectively, b*: Represents yellow and blue. Positive and negative values indicate yellow and blue, respectively

The phenol content of Asian melastome fruit was previously determined as 1.92 g gallic acid equivalent16 (GAE)/100 g and the anthocyanin level in this fruit17 is 49.90 mg L–1. Java plum rind juice had 43-64 mg GAE g–1 and an anthocyanin level of approximately 8.71 mg cyanidin g–1 extract11. Mangosteen rind juice contained 50.51-54.60 mg g–1 total phenol and had an anthocyanin level17 of 5.70-6.20 mg g–1. Antioxidant activity can be analyzed by determining IC50 values that are defined as the concentration of antioxidant compounds that cause the loss of 50% DPPH activity18. Compounds having lower IC50 values have higher antioxidant activity. Here, the IC50 value of Java plum rind juice was lower (101-250 ppm) than that of Asian melastome fruit juice and Mangosteen rind juice (>500 ppm).

Color test: Color is an essential element of food products and is important for consumer preference. Mixing thoroughness during food production is characterized by prevalent and evenly distributed color19. Here, the Hunter lab system was used to test whether the addition of natural colorants improved the color of sugar palm fruit jam (Table 2).

Sugar palm fruit jam with added Asian Melastome fruit juice or rinds from Java plum or Mangosteen rind as natural colorants had varying values for L*, a* and b*, chroma and 0hue (Table 2). The Hunter system is widely used to describe food colors20. In this system, color is divided into 3 dimensions. The symbol a* refers to the red/green component, whereas b* describes the yellow/blue component. The 3rd dimension of color L* indicates lightness or brightness.

According to Hunter system notation, a* values between 0 and +100 indicate red color and those between 0 and -80 indicate green. Meanwhile, b* color intensity expresses a chromatic mixture of blue-yellow wherein a*+b* values from 0 to +70 are yellow and values from 0 to -70 are blue. Values for 0hue represent the dominant wavelength that determines whether colors are red, green and yellow, whereas the chroma value expresses color intensity19,21. The 0hue values can be grouped as follows:

0hue 342-18:Red purple 0hue 162-198: Green
0hue 18-54: Red 0hue 306-342: Purple
0hue 54-90:Yellow red 0hue 270-306: Blue purple
0hue 90-126:Yellow 0hue 198-234: Blue green
0hue 234-270:Blue 0hue 126-162: Yellow green

The addition of Asian melastome fruit juice or juice extracted from Java plum or Mangosteen rinds to sugar palm fruit jam decreased values for L*, a* and b*, chroma and 0hue relative to jam without additives (Table 2). The decline in L* was associated with a darker color, whereas positive values for a* and b* indicated that the jam had a more yellow and red color, respectively.

The 0hue value for sugar palm fruit jam with Asian melastome juice ranged from 1.43-14.00, which translates to a purplish-red color (Table 2). Addition of juice extracted from rinds produced hue values between 20.97 and 32.33, which are associated with a red color (Table 2). The changes in color of sugar palm fruit jam were likely due to the anthocyanin content of the additives13.

Total anthocyanins: Given the change in color produced by the jam additives, we next assessed the anthocyanin content of the jam.

Table 3:Total anthocyanin content of sugar palm fruit jam with additives
Values are Mean±SD, means within the same column with different superscripted letters showed a significant difference

The palm fruit jam with added Asian melastome fruit juice had anthocyanin contents that ranged between 3.50 and 8.57 mg L–1, whereas the addition of Java plum or Mangosteen rind juice produced lower anthocyanin contents that ranged between 3.28 and 11.19 mg L–1 and 1.61 and 3.73 mg L–1, respectively (Table 3). The highest values were seen for jams that had the highest amount (12%) of additive (Table 3).

These results are in contrast to previous analyses which showed that the anthocyanin content in Java plum rind juice was 71.30 mg L–1 juice, whereas Asian melastome fruit juice and Mangosteen rind juice had lower values of 38.91 and 20.48 mg L–1 juice, respectively. The differences between this study and these values may be due to the influence of several factors, including pH, temperature, enzymes, metals and co-pigments on anthocyanin stability. Indeed, Nugraheni22 found that anthocyanin degradation could be influenced by temperature. Moreover, hydroxylated anthocyanin is less heat stable than methylated or glycosylated anthocyanin.

Total phenol: Next measured the effect on phenol content of adding natural colorants during sugar palm fruit jam production. Java plum rind juice added across the 6-12% range produced increases of about 0.6% by weight. Jam with added Asian melastome juice extract had the lowest phenol content (between 1.20 and 1.60%) and Mangosteen fruit rind juice increased the phenol content to 3.51% when added at 12% (Table 4). Jam with added 8% Asian melastome juice had the higher phenol level and then decreased with added 10 and 12% of the fruit juice (Table 4), the more Asian melastome juice added, the higher phenol in the jam, it was assumed that it does not enough solvent to extract al phenols in jam, so not all phenols present in the jam is detected.

Phenolic compounds (polyphenols) are thought to act as antioxidants in Java plums. The astringent and sour taste of Java plum fruits is due to its content of tannin polyphenols, anthocyanins, glycosylated cyanidin, petunidin, malvidin, gallic acid, delphinidin-3-gentiobioside and eyanidindicli glycoside23.

Table 4:Total phenol of sugar palm fruit jam with additives
Values are Mean±SD, means within the same column with different superscripted letters showed a significant difference

Polyphenols are also naturally present in vegetables (broccoli, cabbage, celery), fruits (apple, pomegranate, melon, cherry, pear and strawberries), bean nuts (walnut, soybean, peanut), olive oil and beverages (tea, coffee, chocolate and wine)24. Polyphenols are generally plentiful in fruit rinds. Polyphenol compounds consist of several subclasses namely, flavonol, tannin, isoflavone (soy), flavanone, anthocyanidin, catechin and biflavan. In general, the antioxidant activity of phenolic compounds depends on several factors such as the position and bonding of hydroxyl groups on the aromatic ring, the ability to act as a hydrogen or electron donor and its ability to degrade free radicals.

Phenolic compounds can react with fatty radicals due to the substitution of alkyl groups at positions 2, 4 or 6 that increases the electron density on the hydroxyl group. Radical phenols that form after phenol reacts with fatty radicals are stabilized by delocalization of unpaired electrons to the aromatic ring25. Ukieyanna et al.25 asserted that the total phenolic content accounts for 77% of antioxidant activity in plants.

Antioxidant activity: An antioxidant activity analysis was conducted to determine the IC50 values of the different jams prepared with Asian melastome fruit juice or juice extracts from Java plum or Mangosteen rinds (Table 5). As determined by a DPPH test, all sugar palm fruit jam with additive concentrations ranging from 6-12% had IC50 values >5000 ppm (Table 5). The IC50 values can be defined as the concentration needed to inhibit free radical activity of DPPH by 50%. The IC50 value is inversely proportional to the ability of a substance or substances to act as an antioxidant, wherein smaller IC50 values are associated with greater antioxidant activity19. A compound has very high antioxidant activity if its IC50 value is less than 50 ppm and is inactive if the IC50 value is >500 ppm26. Thus, the additives in this study had no antioxidant activity.

Antioxidants are low molecular weight electron donors or reductant compounds that can inactivate oxidation reactions by preventing the formation of radicals. Antioxidants study by donating an electron to compounds that are oxidized that in turn inhibits the oxidant activity of the recipient molecules.

Table 5:Antioxidant activity (IC50) of sugar palm fruit jam with additives

Antioxidant compounds also can inhibit oxidation reactions and mitigate cell damage by binding free radicals and highly reactive molecules27.

Based on the mechanism of action, antioxidants can be classified into three groups: (1) Primary antioxidants (antioxidants endogenous), which stop the chain reaction of radical formation by providing hydrogen atoms to stabilize radicals, (2) Secondary antioxidants (Exogenous antioxidants), such as metal chelate compounds containing Cu or Fe that act as a proxidant and (3) Tertiary antioxidant, which are compounds that can repair damage caused by radicals and include DNA-repair enzymes and methionine sulfoxide reductase14.

According to Swami et al.28, Java plum fruit is rich in anthocyanin compounds, glucoside and kaempferol, as well as alkaloids, jambosine and jamboline glycosides that can act as antioxidants. Asian melastome fruit has a total antioxidant activity of 5.878 μM Acid Equivalent Antioxidant Capacity (AEAC) g–1 dry weight and 157.15 mg/100 g dry weight as determined with DPPH16. Meanwhile, Mangosteen rind is rich in pectin and bioactive compounds, such as phenolic compounds, anthocyanins and xanthone, which is a powerful antioxidant compound29. Xanthone compounds are organic compounds derived from diphenyl-γ-pyron that can be grouped according to the phenol or polyphenolic type25.

The very low antioxidant activity we found in sugar palm fruit jam is likely not due to processing factors but instead may be because the additives had a very low phenolic content. Antioxidant activity can be influenced by physical factors, such as high oxygen pressure, heating or irradiation and moisture content of materials30. Thus, the temperature used in jam processing should be kept below 50°C to avoid damage to compounds with antioxidant activity.


Here we found that the addition of Asian melastome fruit juice or juice extracts from Java plum rind or Mangosteen rind added during production of sugar palm fruit jam significantly affected the color, total anthocyanin content and total phenol content of the jam that was produced. However, the antioxidant capacity of the jam was not affected (>5,000 ppm). Color test results indicated that the addition of Asian melastome fruit juice and Java plum rind juice gave a red purple color to the jam (0hue: 1:43-14:00), whereas jam made with Mangosteen rind juice was red (0hue: 20.97-32.33).

Anthocyanin levels in sugar palm fruit jam with added Asian melastome fruit juice, Java plum rind juice and Mangosteen rind juice increased with increasing amounts of additive.


This study is a Research Cluster Grant Professor for fiscal year 2016 and was funded by the University of Andalas under contract No. 99/UN.16/HKRGB/LPPM/2016.

1:  Torio, M.A.O., J. Saez and F.E. Merca, 2006. Physicochemical characterization of galactomannan from sugar palm (Arenga saccharifera Labill.) endosperm at different stages of nut maturity. Philippine J. Sci., 135: 19-30.
Direct Link  |  

2:  Sittikijyothin, W., D. Torres and M.P. Goncalves, 2005. Modelling the rheological behaviour of galactomannan aqueous solutions. Carbohydrate Polymers, 59: 339-350.
CrossRef  |  Direct Link  |  

3:  Srivastava, M. and V.P. Kapoor, 2005. Seed galactomannans: An overview. Chem. Biodiver., 2: 295-317.
CrossRef  |  Direct Link  |  

4:  Boual, Z., G. Pierre, C. Delattre, F. Benaoun and E. Petit et al., 2015. Mediterranean semi-arid plant Astragalus armatus as a source of bioactive galactomannan. Bioactive Carbohydrates Dietary Fibre, 5: 10-18.
CrossRef  |  Direct Link  |  

5:  Arja, F.S., D. Darwis and A. Santoni, 2013. Isolasi, identifikasi, dan uji antioksidan senyawa antosianin dari buah sikaduduak (Melastoma malabatricum L.) serta aplikasi sebagai pewarna alami. J. Kimia Unand., 2: 124-127.

6:  Roobha, J.J., M. Saravanakumar, K.M. Aravindhan and P.S. Devi, 2011. The effect of light, temperature, pH on stability of anthocyanin pigments in Musa acuminata bract. Res. Plant Biol., 1: 5-12.
Direct Link  |  

7:  Devi, P.S., M. Saravanakumar and S. Moh, 2012. The effects of temperature and pH on stability of anthocyanins from red sorghum (Sorghum bicolor) bran. Afr. J. Food Sci., 6: 567-573.
Direct Link  |  

8:  Sayuti, K., N. Hamzah, T. Anggraini and N. Andesta, 2011. The effect of temperature and drying time on the characteristic of reddish grey fruit instant powder (Sizyqium cumini). Pak. J. Nutr., 10: 846-850.
CrossRef  |  Direct Link  |  

9:  Sayuti, K., F. Azima and M. Marisa, 2015. The addition of Senduduk fruit (Melastoma malabathricum L.) extract as colorants and antioxidant on jackfruit straw (Artocarpus heterophyllus L.) Jam. Int. J. Adv. Sci. Eng. Inform. Technol., 5: 396-401.
Direct Link  |  

10:  Chaovanalikit, A., A. Mingmuang, T. Kitbunluewit, N. Choldumrongkool, J. Sondee and S. Chupratum, 2012. Anthocyanin and total phenolics content of mangosteen and effect of processing on the quality of mangosteen products. Int. Food Res. J., 19: 1047-1053.
Direct Link  |  

11:  Siti-Azima, A.M., A. Noriham and M. Nurhuda, 2013. Antioxidant activities of Syzygium cumini and Ardisia elliptica in relation to their estimated phenolic compositions and chromatic properties. Int. J. Biosci. Biochem. Bioinform., 3: 314-317.
Direct Link  |  

12:  Sanchez, T., H. Ceballos, D. Dufour, D. Ortiz and N. Morante et al., 2014. Prediction of carotenoids, cyanide and dry matter contents in fresh cassava root using NIRS and Hunter color techniques. Food Chem., 151: 444-451.
CrossRef  |  PubMed  |  Direct Link  |  

13:  Lee, J., R.W. Durst and R.E. Wrolstad, 2005. Determination of total monomeric anthocyanin pigment content of fruit juices, beverages, natural colorants and wines by the pH differential method: Collaborative study. J. AOAC Int., 88: 1269-1278.
Direct Link  |  

14:  Sayuti, K. and R. Yenrina, 2015. Antioksidan: Alami dan Sintetik. Unand Press, Padang.

15:  Huang, Y.C., Y.H. Chang and Y.Y. Shao, 2006. Effects of genotype and treatment on the antioxidant activity of sweet potato in Taiwan. Food Chem., 98: 529-538.
CrossRef  |  Direct Link  |  

16:  Nayak, J. and U.C. Basak, 2015. Analysis of some nutritional properties in eight wild edible fruits of Odisha, India. Int. J. Curr. Sci., 14: 55-62.
Direct Link  |  

17:  Aishah, B., M. Nursabrina, A. Noriham, A.R. Norizzah and H.M. Shahrimi, 2013. Anthocyanins from hibiscus sabdariffa, Melastoma malabathricum and ipomoea batatas and its color properties. Int. Food Res. J., 20: 827-834.
Direct Link  |  

18:  Molyneux, P., 2004. The use of the stable free radical diphenylpicrylhydrazyl (DPPH) for estimating antioxidant activity. Songklanakarin J. Sci. Technol., 26: 211-219.
Direct Link  |  

19:  Winarno, F.G., 2004. Kimia Pangan dan Gizi. [Food Chemistry and Nutrition]. PT Gramedia Pustaka Utama, Jakarta, Pages: 253.

20:  DeMann, J.M., 1989. Principle of Food Chemistry. The Avi Pub Co. Inc., Westport, Connecticut, pp: 17-18.

21:  Andarwulan, N., F. Kusnandar and D. Herawati, 2011. Analisis Pangan. Dian Rakyat, Jakarta.

22:  Nugraheni, M., 2014. Pewarna Alami Sumber dan Aplikasinya Pada Makanan dan Kesehatan. Yogyakarta Graha Ilmu, Indonesia, Pages: 182.

23:  Ayyanar, M. and P. Subash-Babu, 2012. Syzygium cumini (L.) Skeels: A review of its phytochemical constituents and traditional uses. Asian Pacific J. Trop. Biomed., 2: 240-246.
CrossRef  |  Direct Link  |  

24:  Miryanti, Y.I.P.A., L. Sapei, K. Budiono and S. Indra, 2011. Ekstraksi antioksidan dari kulit buah manggis (Garcinia mangostana L.). Res. Rep. Eng. Sci., 2: 1-52.
Direct Link  |  

25:  Ukieyanna, E., Suryani and A.P. Roswiem, 2012. Aktivitas Antioksidan kadar fenolik dan flavonoid total tumbuhan suruhan. Skripsi. Departemen Biokimia IPB., Bogor.

26:  Jun, M., H.Y. Fu, J. Hong, X. Wan, C.S. Yang and C.T. Ho, 2003. Comparison of antioxidant activities of isoflavones from kudzu root (Pueraria lobata Ohwi). J. Food Sci., 68: 2117-2122.
CrossRef  |  Direct Link  |  

27:  Winarsi, H., 2007. Antioksidan Alami dan Radikal Bebas. Penerbit Kanisius, Yogyakarta, Pages: 281.

28:  Swami, S.B., N.S.J. Thakor, M.M. Patil and P.M. Haldankar, 2012. Jamun (Syzygium cumini (L.)): A review of its food and medicinal uses. Food Nutr. Sci., 3: 1100-1117.
CrossRef  |  Direct Link  |  

29:  Chhouk, K., A.T. Quitain, D.G. Pag-asa, J.B. Maridable, M. Sasaki, Y. Shimoyama and M. Goto, 2016. Supercritical carbon dioxide-mediated hydrothermal extraction of bioactive compounds from Garcinia mangostana pericarp. J. Supercritical Fluids, 110: 167-175.
CrossRef  |  Direct Link  |  

30:  Pokorny, J., N. Yanishlieva and M. Gordon, 2001. Antioxidant in Food. Woodhead Publishing Ltd., England.

©  2020 Science Alert. All Rights Reserved