CHANGES IN COLOR PARAMETERS OF HUMMUS ENRICHED WITH BLACK SEED (NIGELLA SATIVA) OIL DURING STORAGE
Keywords:
Hummus, Nigella sativa oil, color parameters, storageAbstract
Hummus is a widely consumed plant-based spread whose popularity has continuously increased due to its favorable nutritional profile and potential for functional enrichment. In such products, visual appearance, particularly color, represents one of the first and most important quality attributes shaping consumer perception and acceptance. Changes in color may also serve as an indicator of physical and chemical processes occurring during storage, especially in semi-solid plant-based matrices such as hummus.
The aim of this study was to investigate the effect of different concentrations of Nigella sativa oil (NSO) on the color characteristics and color stability of hummus during storage. Five hummus formulations were prepared, including a control sample and samples containing 4, 6, 8, and 12% NSO, expressed as a proportion of the total lipid phase. All samples were stored at 4 ± 1 °C for a period of 21 days.
Color parameters L*, a*, and b* were determined using image-based color analysis, with digital image processing followed by transformation from the RGB system to the CIE Lab color model. The total color difference (ΔE) was calculated in order to assess the visual perceptibility of color changes during storage. Statistical analysis revealed that storage time had a significant effect on all color parameters (p < 0.05), whereas the effect of NSO concentration was limited, with statistically significant differences observed only for L* values. During storage, L* values initially decreased up to day 14, indicating slight darkening of the samples, followed by a pronounced increase on day 21. The a* parameter progressively shifted toward more negative values, suggesting changes in the red–green balance, while b* values showed a continuous increase, indicating enhanced yellowish tones. The ΔE values increased throughout the storage period and reached an average value of 16.11 after 21 days, corresponding to a clearly perceptible visual color change. Higher NSO concentrations were associated with increased variability and higher ΔE values, particularly in the sample containing 12% NSO.
Overall, the results indicate that the color of hummus remains relatively stable during the first 2 weeks of storаge at 4 ± 1 °C, after which visually noticeable changes occur. The incorporation of Nigella sativa oil contributes to the evolution of color during storage, highlighting the importance of optimizing the level of functional lipid enrichment in order to maintain the visual quality of hummus-based products.
References
Andrés-Bello, A., Barreto-Palacios, V., García-Segovia, P., Mir-Bel, J., & Martínez-Monzó, J. (2013). Effect of pH on color and texture of food products. Food Engineering Reviews, 5(3), 158–170. https://doi.org/10.1007/s12393-013-9067-2
Arslan, D., & Acar, A. (2024). Effects of different postharvest storage conditions of black cumin seeds on the oxidative stability of cold pressed oil. La Rivista Italiana Delle Sostanze Grasse, 101, 165–174.
Cheikh-Rouhou, S., Besbes, S., Hentati, B., Blecker, C., Deroanne, C., & Attia, H. (2007). Nigella sativa L.: Chemicalcomposition and physicochemical characteristics of lipid fraction. Food Chemistry, 101, 673–681. https://doi.org/10.1016/j.foodchem.2006.02.022
Delinikolova, E. & Jankuloska V. (2025). Sensory analysis of chickpea hummus enriched with cold-pressed blackseed oil. Knoweledge - International Journal, 68(3), 343–347.
Dutta, K., & Nath, R. (2023). Application of colorimetry in food industries. In IntechOpen eBooks.https://doi.org/10.5772/intechopen.112099
Faridy, J. M., Stephanie, C. M., Gabriela, M. O., & Cristian, J. (2020). Biological Activities of Chickpea in Human
Health (Cicer arietinum L.). A Review. Plant Foods for Human Nutrition, 75(2), 142–153. https://doi.org/10.1007/s11130-020-00814-2
Goswami, M., Kumar, R., Teng, X. M., Jadeja, R., Scott, D., Pfeiffer, M., Mafi, G. G., Pathak, V., & Ramanathan, R.
(2025). Physicochemical, nutritional, and structural characterization of a novel Meat Based hummus. Foods, 14(14), 2507. https://doi.org/10.3390/foods14142507
Kiciak, A., Kuczka, N., Barczyńska, R., Staśkiewicz-Bartecka, W., Białek-Dratwa, A., Sapała, A., Kowalski, O., &
Kardas, M. (2025). Analysis of the quality of selected vegetarian products available on the Polish market compared to their homemade equivalents. Foods, 14(5), 891. https://doi.org/10.3390/foods14050891
Lukinac Čačić J. (2012). Mathematical modeling and optimization of the bread browning kinetics during baking,Sveuĉilište Josipa Jurja Strossmayera u Osijeku, Prehrambeno-Tehnološki fakultet Osijek (Ph.D thesis in croatian).
Macdougall, D. (2010). Colour measurement of food: principles and practice. In Elsevier eBooks (pp. 312–342).https://doi.org/10.1533/9780857090195.2.312
Martínez-Zamora, L., Castillejo, N., & Artés-Hernández, F. (2023). Ultrasound and microwave treatments preservedquality of a pepper-based hummus enriched in mustard sprouts. LWT, 185, 115178. https://doi.org/10.1016/j.lwt.2023.115178
Nakov G., Jankuloska V., Dimov, I. & Taneva I. (2019). Influence of food by-products on the color of backery products. International Conference on Technics, Technologies and Education ICTTE 2019, 478 -486.
Papanikolaou, Y., & Fulgoni, V. L. (2008). Bean Consumption Is Associated with Greater Nutrient Intake, Reduced
Systolic Blood Pressure, Lower Body Weight, and a Smaller Waist Circumference in Adults: Results from the National Health and Nutrition Examination Survey 1999-2002. Journal of the American College of Nutrition, 27(5), 569–576. https://doi.org/10.1080/07315724.2008.10719740
Pathare, P. B., Opara, U. L., & Al-Said, F. A. (2012). Colour measurement and analysis in fresh and Processed foods:a review. Food and Bioprocess Technology, 6(1), 36–60. https://doi.org/10.1007/s11947-012-0867-9
Rebello, C. J., Greenway, F. L., & Finley, J. W. (2014). Whole Grains and Pulses: A comparison of the nutritionaland health benefits. Journal of Agricultural and Food Chemistry, 62(29), 7029–7049. https://doi.org/10.1021/jf500932z
Segev, A., Badani, H., Kapulnik, Y., Shomer, I., Oren‐Shamir, M., & Galili, S. (2010). Determination of Polyphenols,Flavonoids, and Antioxidant Capacity in Colored Chickpea ( Cicer arietinum L.). Journal of Food Science, 75(2), S115-9. https://doi.org/10.1111/j.1750-3841.2009.01477.x
Shahein, M., Albawarshi, Y., Al-khamaiseh, A., El-Eswed, B., Kanaan, O., & Majdalawi, M. (2025). Non-thermalshelf-life extension of fresh hummus by high hydrostatic pressure and refrigerated storage. Discover Food, 5(111). https://doi.org/10.1007/s44187-025-00363-0
Wallace, T., Murray, R., & Zelman, K. (2016). The nutritional value and health benefits of chickpeas and hummus.Nutrients, 8(12), 766. https://doi.org/10.3390/nu8120766
Xu, B., Yuan, S., & Chang, S. (2007). Comparative analyses of phenolic composition, antioxidant capacity, and colorof cool season legumes and other selected food legumes. Journal of Food Science, 72(2), S16777. https://doi.org/10.1111/j.1750-3841.2006.00261.x
Yamani, M. I., & Mehyar, G. F. (2011). Effect of chemical preservatives on the shelf life of hummus during differentstorage temperatures. Jordan Journal of Agricultural Sciences, 7(1), 19–31.
