Valorization of Citrus Peel Waste

Year 2018, Volume: 5 Issue: 2, 10 - 18, 27.12.2018

Merve Deniz Köse Oğuz Bayraktar

Abstract

Citrus sinensis commercially known as an orange tree has a high pectin ratio and
valuable essential oils. The huge amount of orange peel is generated in
industries and they can be used as a raw material for essential oils and
pectin. To obtain essential oils from orange peels distillation method is used
and collected oil is analyzed to determine its d- limonene amount, also the
yield of the essential oil production is calculated. The essential oil yield
was found as 0.19%. GC results revealed that the sample had 94% d-limonene, and
the data from the literature indicated that d-limonene amount of orange
essential oil may vary between 32% and 98% depending on the variety of orange.
In addition to essential oil, pectin was also extracted from the orange peels
using two types of acids. First one was hydrochloric acid (HCl) as an inorganic
acid, and the other was tartaric acid (TA) as an organic acid. The purpose of
selecting the several types of acid was to observe the effects of acid type on
pectin yield. The pectin amount obtained with HCl usage (4.72 % g pectin/orange
fresh peel) was higher than that with TA usage (4.037 % g pectin/orange fresh
peel). The experimental results for pectin contents of samples were also
confirmed with the colorimetric test results. According to these results,
concentrations of galacturonic acid in the samples obtained with HCl (0.509 mg
galacturonic acid/mg) was found to be higher than the concentrations of
galacturonic acid in the samples obtained with TA (0.103 mg galacturonic
acid/mg).

Keywords

Essential oils, valorization, extraction of pectin, orange peel

References

• BeMiller, J. N. (1986). An Introduction to Pectins: Structure and Properties. Chemistry and Function of Pectins Fishman and Jen; Chapter 1, 2–12.
• Blumenkrantz, N., Asboe-Hansen, G. (1973). New method for quantitative determination of uronic acids. Analytical Biochemistry 54, 484-489.
• Board, N., 2011. The Complete Technology Book of Essential Oils (aromatic Chemicals). India: National Institute of Industrial Research.
• Diaz, S., Espinosa, S., Brignole, E., (2005). Citrus peel oil deterpenation with supercritical fluids optimal process and solvent cycle design. Supercritical Fluids, 35, 49-61.
• Hayat, K., Zhang, X., Chen, H., Xia, S., Jia, C., Zhong, F., (2010). Liberation and separation of phenolic compounds from citrus mandarin peels by microwave heating and its effect on antioxidant activity. Separation and Purification Technology 73, (3), 371–376.
• Georgiev, Y., Ognyanov, M., Yanakieva, I., Kussovski, V., Kratchanova, M. (2012). Isolation, characterization, and modification of citrus pectins. Journal of BioScience and Biotechnology, 1 (3), 223-233.
• Gnanasambandam, R., Proctor, A., (2000). Determination of pectin degree of esterification by diffuse reflectance Fourier transform infrared spectroscopy. Food Chemistry 68 (3), 327–332.
• Joye, D.D., Luzio, G.A., (2000). Process for Selective Extraction of Pectins from Plant Material by Different pH. Carbohydrate Polymers 43, 337-342.
• Kaya, M., Sousa, A. G., Crépeau, M.-J., Sørensen, S. O., & Ralet, M.-C. (2014). Characterization of citrus pectin samples extracted under different conditions: influence of acid type and pH of extraction. Annals of Botany, 114 (6), 1319–1326.
• Kontogiannopoulos, K.N., Patsios, S. I., Karabelas, A. J. (2016). Tartaric Acid Recovery from Winery Lees Using Cation Exchange Resin: Optimization by Response Surface Methodology. Separation and Purification Technology 165, 32–41.
• Rezzadoria, K., Benedettia, S., Amanteb., E.R. (2012). Proposals for the residues recovery: Orange waste as raw material for new products. Food and Bioproducts Processing, 90, 606-614.
• Ruiz, B., Flotats, X., (2014). Citrus Essential Oils and Their Influence on the Anaerobic Digestion Process: An Overview. Waste Management, 34, 2063-2079.
• Silverstein, R. M., Bassler, G. C., Morril, T. C. (1991). Infrared spectroscopy. In Spectrometric identification of organic compounds (5th ed., pp. 91-164). New York: JohnWiley & Sons, Inc. (Chapter3).