Carob Sugars: Sucrose, Glucose, and Fructose
The most distinctive feature that distinguishes carob from other leguminous fruits is the high sugar content of the pulp. Most of this sweetness comes from sucrose; glucose and fructose are found in lower proportions, but in proportions that affect the taste and processing behavior of the product.
In this article, we discuss the sugar profile of carob pulp, how this profile varies according to variety, region and ripeness, how processes such as extraction, roasting and fermentation affect sugars, and where carob is used as a natural sweetener based on scientific sources.
Where Does the Sweetness of Carob Come From?
Although carob fruit is a dry, hard-looking pod, it is distinctly sweet when taken into the mouth. This sweetness is due to the fact that the fruit flesh is rich in carbohydrates. According to a review comparing carob data from different countries in the Mediterranean basin, the total sugar content of the pulp usually ranges from 45 to 58 percent on dry weight, with the main sugars being sucrose, fructose, and glucose (Correia & Pestana, 2024). Another comprehensive review states that carob pulp contains 48–56 percent total sugar (Goulas et al., 2016).
In a doctoral study conducted in Turkey, it was stated that carob fruit contains approximately 40-70 percent sugar depending on the type, region and climate, and most of this sugar is sucrose (Yalım Kaya, 2010). This difference in spacing between sources shows that carob is not a uniform raw material; it shows that it is a product that varies according to the variety, growing conditions and analysis method.
It is also important to know in which part of the fruit the sugars are collected. According to the same review, when the seeds are separated in the ground fruit after harvest, the remaining pulp constitutes 80–90 percent of the pod by weight (Correia and Pestana, 2024). Sugars are found in this pulp; the kernel is not valuable in terms of sugar, but in terms of galactomannan, the raw material of the carob gum.
The Three Basic Sugars: Sucrose, Glucose, and Fructose
To understand the sugar profile of carob, it is necessary to first briefly get to know these three sugars:
| Sucrose | It is a disaccharide formed by the combination of a glucose and a fructose unit. The sugar known as table sugar is also sucrose. |
| Glucose | It is a single-unit (monosaccharide) sugar; it occurs naturally in fruits and products such as honey. |
| Fructose | It is also a single-unit sugar; it is also referred to as fruit sugar. |
The predominant sugar in carob is by far sucrose. In the review by Goulas et al. (2016), it is stated that sucrose is the main carbohydrate in carob and can reach up to 52 grams per 100 grams in dry matter. Correia and Pestana (2024) state that sucrose is approximately 35–45 percent, fructose is 6–7 percent, and glucose is 2–4 percent in the dry weight of the pulp.
An example from Turkey requires looking at this picture from a different perspective. Ayaz et al. (2007), who examined carob collected from Western and Southern Anatolia, reported the main sugars in the fruit as 437.3 mg/g for sucrose, 395.8 mg/g for glucose and 42.3 mg/g for fructose in dry weight. In this study, although the highest sugar was sucrose, the glucose value was well above the general ranges reported in the reviews. Since such differences may depend on sampling, variety and analysis method, it is more accurate to think in terms of ranges rather than generalizing the figures of a single study.
| Source | Material | Reported sugar information |
|---|---|---|
| Correia and Pestana, 2024 | Compilation of pulp data from Mediterranean countries | Total sugar 45–58%; sucrose 35–45%, fructose 6–7%, glucose 2–4% (dry weight) |
| Goulas et al., 2016 | Compilation | Total sugar 48–56%; sucrose up to 52 g in 100 g of dry matter |
| Ayaz et al., 2007 | Western and Southern Anatolian carob pods | Sucrose 437.3; glucose 395.8; fructose 42.3 mg/g dry weight |
| Tetik et al., 2011 | 10 carob syrups from the Turkish market | Average sucrose 385.90; glucose 152.44; fructose 162.03 g/kg dry weight |
Why Does the Sugar Profile Change?
The sugar content of carob can vary from tree to tree, even within the same country. The main reasons for this variability are:
Difference between grafted and wild trees: In a study conducted in the Mediterranean region of Turkey, the total sugar content of grafted (cultured) carob pods was found to be 53.1 percent in dry weight and 43.7 percent in pods of wild (ungrafted) trees (Biner et al., 2007; Correia and Pestana, in 2024). This difference helps to understand why grafted varieties are preferred in commercial production.
Variety and genetics: In pulp powders obtained from 19 carob varieties grown under the same conditions on the Spanish island of Majorca, the total sugar ranged from 22.5 to 62.5 grams per 100 grams of dry matter; significant differences were observed between the varieties, especially in fructose content (Garau et al., 2025). In a large-scale screening conducted in Cyprus, it was reported that the total sugar content was mostly related to genetic structure, while sucrose was mostly related to both genetic and environmental factors (Correia and Pestana, 2024).
Maturity: Sugar accumulation changes with the ripening of the fruit. In a study in Morocco that monitored immature carob pods at different developmental stages, it was observed that the total amount of sugar varied between stages, while the Brix value began to decrease in the last stages of the immature period studied (Laaraj et al., 2026). Therefore, harvest time is one of the factors affecting the sugar profile of the raw material.
Territory and soil: In the review, it was emphasized that the total sugar values reported from Algeria, Morocco, Spain, Portugal, Greece, and Cyprus were widely distributed, and studies based on multi-year sampling from the same trees were needed (Correia and Pestana, 2024).
Next to Sugars: D-Pinitol
In addition to sucrose, glucose and fructose, carob pulp also contains a cyclitol (a sugar alcohol-like compound) called D-pinitol. D-pinitol is not a sugar in the classical sense; however, since it is in the soluble fraction with sugars, it is examined together with the sugar profile.
Turhan (2014) reported that D-pinitol concentration was positively correlated with glucose concentration in wild and cultivated carob in Turkey and was found to be higher in wild trees (mean 42.6 g/kg) than in cultivated trees (mean 37.8 g/kg) (Correia and Pestana, in 2024). In other words, although wild carob contains less sugar, it may be richer in D-pinitol. D-pinitol What is D-Pinitol in Carob? We discussed it in detail in our article.
How Does Processing Affect Sugars?
Carob fruit mostly reaches the consumer in processed forms such as powder, molasses, syrup or extract. Each processing step can affect the sugar profile differently.
Extraction
The first step in the production of molasses and syrup is the extraction of sugars from the fruit with hot or cold water. A study conducted in Cyprus stated that the source of the raw material affects not only the amount of phenolic compounds but also the ratio of sucrose, glucose, and fructose in the extract to each other, which can alter the perceived sweetness of the product. In the same study, it was observed that increasing the temperature increased the dissolution of phenolic compounds more than sugars, while extending the time at low temperature improved sugar yield (Antoniou et al., 2020).
Yalım Kaya (2010) also emphasized that in conditions where sugar is well extracted, undesirable components that give turbidity, bitterness, astringency and color are also extracted; he optimized factors such as particle size, water-fruit ratio, temperature and time to find the condition in which sugar is most soluble and other components are least soluble.
Thickening: Syrup and Molasses
In syrup and molasses obtained by condensing the extract, sucrose is also the prominent sugar. The average values of 10 carob syrups purchased from the market in Turkey were found to be 385.90 g/kg for sucrose, 152.44 g/kg for glucose and 162.03 g/kg for fructose in dry weight (Tetik et al., 2011). The share of glucose and fructose in the total in these syrups is significantly higher than the ratios given in the compilations for fruit; it should be considered that the difference may be related to raw materials and processing conditions.
Roasting
Roasting is frequently used in the production of carob powder. In a study conducted in Turkey, hot air, microwave and roasting methods using them together were compared; it was reported that roasting reduced the sugar content of carob powder and increased the D-pinitol content. In the same study, it was determined that the main sugar was sucrose, followed by fructose and glucose (Gunel et al., 2020). It has been shown that Maillard reaction products and brown polymers called melanoids are formed during roasting (Grigoriou & Pinakoulaki, 2021); caramel and cocoa-like aromas in carob flour are also reported to be associated with Maillard-derived compounds (Makhlouf et al., 2026).
Fermentation
When carob flour is fermented with sourdough, a significant portion of the sugars are consumed by microorganisms. In a study conducted in Spain, the sugar content in carob-wheat sourdough decreased by 90–98 percent, while this decrease remained at the level of 60 percent in sourdough prepared only from carob flour; the pinitol content remained unchanged (Sanmartín et al., 2025). This finding indicates that the sugar profile of fermented carob products may be very different from that of raw products.
Carob as a Natural Sweetener
The high sucrose content has historically made carob a source of sweetening. A recent review also states that carob has traditionally been valued as animal feed and natural sweetener (Ben Hsouna et al., 2026). Today, this property is valued in different product groups:
| Molasses and syrups | It is the condensed form of carob's natural sugars and is used for breakfast or as a sweetener. |
| Purified sugar syrup | The production and purification of sugar syrup from carob has been a subject that has been researched for a long time (Petit and Pinilla, 1995). The syrup obtained in the process developed by Yalım Kaya (2010) was found to comply with the Turkish Food Codex Sugar Communiqué and TS 12067 Invert Sugar Syrup Standard; a product with low total polyphenol content and high clarity was obtained. |
| Baked goods | Carob flour contributes both color, aroma, and sweetness to products such as biscuits and cakes. In a biscuit study conducted with carob flour originating from Algeria, the use of 30 and 60 percent of the flour significantly increased color intensity, caramel odor, sweetness, and chocolatey flavor (Makhlouf et al., 2026). |
| Beverages | The sweetness of carob juice and similar drinks also comes from the fruit's own sugars. |
The effects of carob-based sweeteners on blood sugar are also being investigated. In a study conducted with healthy adults in Spain, the glycemic index of two commercial carob syrups was found to be 56.04 and 60.46; the authors emphasized that the results should be interpreted as preliminary evidence (Planes-Muñoz et al., 2025). Another study comparing a beverage containing pinitol, prepared with a carob-derived sweetener, to a sucrose drink is an example of research in this area (Lambert et al., 2018). These findings do not mean that carob products are "sugar-free"; carob molasses and syrup are sugar-dense products and, like other sugary foods, should be consumed in moderation. For details on blood sugar Carob and Blood Sugar You can check our article.
Practical Notes for Food Manufacturers
For manufacturers who use carob as a sweetening or flavor ingredient, the sugar profile is a direct part of the formulation:
- When carob powder or molasses is used, the total sugar value of the product increases even if there is no added sugar. When preparing the nutrition statement, the analysis values of the raw material should be taken as basis.
- Since sugar content can vary from batch to batch, requesting proof of analysis from the supplier that includes parameters such as total sugar or Brix ensures consistency.
- As the degree of roasting increases, the sugar decreases, the color and aroma become darker; the balance between sweetness and aroma should be established according to the choice of roasting.
- In products using sourdough or fermentation, a significant portion of sugar can be consumed; the sweetness expectation should be adjusted accordingly.
Added sugar in carob products and the issue of labels. Is There Added Sugar in Carob Products? In our article, general nutritional values Nutritional Values of Carob We discussed it in our article.
Frequently Asked Questions
Which sugar is most abundant in carob? Sucrose. Reviews report that sucrose makes up about 35–45 percent of the pulp dry weight and can be up to 52 grams per 100 grams in dry matter.
Is wild carob less sweet? In a study conducted in Turkey, total sugar was found to be lower in the pods of wild trees than in grafted trees. On the other hand, it has been reported that D-pinitol levels may be higher in wild carob.
Is roasted carob powder less sugary? There are studies showing that roasting reduces sugar content. However, roasted powder also remains a sugar-rich product.
Can carob molasses be used as a sugar substitute? It can be used for sweetening purposes; however, molasses also contains intense sugar. Considering that it replaces sugar, it should not be consumed too much.
The Natural Sweetness of Carob with Carob Türkiye
Carob's sugar profile makes it valuable in both traditional products and modern food formulations. At Carob Türkiye, we supply carob fruit, cracks, flour/powder, kernels, and extracts. Our Products Carob Fruit, Carob Kibble (Granular), Carob Flour / Powder and Carob Extract You can review it from the pages; For your wholesale and export requests Contact Now You can contact us on our page.
This content is for informational purposes only; it is not a substitute for medical advice.
Domestic resources
Ayaz, F. A., Torun, H., Ayaz, S., Correia, P. J., Alaiz, M., Sanz, C., Gruz, J., Strnad, M., "Determination of chemical composition of Anatolian carob pod (Ceratonia siliqua L.): sugars, amino and organic acids, minerals and phenolic compounds", Journal of Food Quality, 30(6), 1040–1055, 2007. doi.
org/ 10. 1111/ j. 1745- 4557. 2007. 00176. x Biner, B., Gubbuk, H., Karhan, M., Aksu, M., Pekmezci, M., "Sugar profiles of the pods of cultivated and wild types of carob bean (Ceratonia siliqua L.) in Turkey", Food Chemistry, 100(4), 1453–1455, 2007. doi.
org/ 10. 1016/ j. foodchem. 2005. 11. 037 Turhan, İ., "Relationship Between Sugar Profile and D-Pinitol Content of Pods of Wild and Cultivated Types of Carob Bean (Ceratonia siliqua L.)", International Journal of Food Properties, 17(2), 363–370, 2014. doi.
org/ 10. 1080/ 10942912. 2011. 631255 Tetik, N., Turhan, İ., Oziyci, H. R., Karhan, M., "Determination of D-pinitol in carob syrup", International Journal of Food Sciences and Nutrition, 62(6), 572–576, 2011. doi.
org/ 10. 3109/ 09637486. 2011. 560564 Yalım Kaya, S., "Production of high purity sugar syrup from carob fruit", PhD Thesis, Mersin University Institute of Natural and Applied Sciences, 2010 (YÖK Thesis No: 283071). Tezara.
org/ theses/ 283071 Günel, Z., Torun, M., Şahin-Nadeem, H., "Sugar, d-pinitol, volatile composition, and antioxidant activity of carob powder roasted by microwave, hot air, and combined microwave/hot air", Journal of Food Processing and Preservation, 44(4), e14371, 2020. doi.
org/ 10. 1111/ jfpp. 14371 Foreign sources
Correia, P. J., Pestana, M., "Sugars and phenols in carob tree fruits from different producing countries: A short review", Heliyon, 10(10), e30922, 2024. doi.
org/ 10. 1016/ j. helion. 2024. E30922 Goulas, V., Stylos, E., Chatziathanasiadou, M. V., Mavromoustakos, T., Tzakos, A. G., "Functional Components of Carob Fruit: Linking the Chemical and Biological Space", International Journal of Molecular Sciences, 17(11), 1875, 2016. doi.
org/ 10. 3390/ ijms17111875 Garau, C., Umaña, M., Llompart, M., Velázquez, I., Gálvez, I., Simal, S., "Potential of Carob Pulp Powder: Influence of Cultivar on Nutritional Composition, Antioxidant Activity, and Functional Properties", Molecules, 30(13), 2715, 2025. doi.
org/ 10. 3390/ molecules30132715 Laaraj, S. et al., "Maturation-Associated Physiological and Biochemical Transitions in Carob (Ceratonia siliqua L.): Optimizing Harvest Timing Toward Functional Valorization of Fruits", The Scientific World Journal, 2026, e5395647, 2026. doi.
org/ 10. 1155/ tswj/ 5395647 Antoniou, C., Kyratzis, A., Rouphael, Y., Stylianou, S., Kyriacou, M. C., "Heat- and Ultrasound-Assisted Aqueous Extraction of Soluble Carbohydrates and Phenolics from Carob Kibbles of Variable Size and Source Material", Foods, 9(10), 1364, 2020. doi.
org/ 10. 3390/ foods9101364 Sanmartín, G., Prieto, J. A., Morard, M., Estruch, F., Blasco-García, J., Randez-Gil, F., "The Effects of Sourdough Fermentation on the Biochemical Properties, Aroma Profile and Leavening Capacity of Carob Flour", Foods, 14(10), 1677, 2025. doi.
org/ 10. 3390/ foods14101677 Petit, M. D., Pinilla, J. M., "Production and purification of a sugar syrup from carob pods", LWT – Food Science and Technology, 28(1), 145–152, 1995. doi.
org/ 10. 1016/ S0023- 6438(95)80027- 1 Makhlouf, F. Z. et al., "Physicochemical and Sensory Profiling of Carob Flour and Effects of Its Incorporation on Quality Characteristics of Wheat-Based Biscuits", Foods, 15(16), 2785, 2026. doi.
org/ 10. 3390/ foods15162785 Planes-Muñoz, D., Rosell, M. L. Á., Frontela-Saseta, C., López-Nicolás, R., "Evaluation of Commercial Carob Syrups (Ceratonia siliqua L.) in Randomized Controlled Trials: Effects on Lipid, Glycaemic, and Anthropometric Parameters", Foods, 14(21), 3676, 2025. doi.
org/ 10. 3390/ foods14213676 Lambert, C., Cubedo, J., Padró, T., Vilahur, G., López-Bernal, S., Rocha, M., Hernández-Mijares, A., Badimon, L., "Effects of a Carob-Pod-Derived Sweetener on Glucose Metabolism", Nutrients, 10(3), 271, 2018. doi.
org/ 10. 3390/ nu10030271 Grigoriou, A. M., Pinakoulaki, E., "Linking the Dynamic Changes in the In Vitro Antioxidant Activity of Carob Kibbles upon Roasting to the Chemical and Structural Changes Revealed by FTIR Spectroscopy", Antioxidants, 10(12), 2025, 2021. doi.
org/ 10. 3390/ antiox10122025 Ben Hsouna, A. et al., "Ceratonia siliqua: Phytochemistry, Bioactivity, and Its Emerging Role as a Sustainable Food and Industrial Resource", Journal of Food Science, 91(10), e71527, 2026. doi.
Scientific Resourcesorg/ 10. 1111/ 1750- 3841. 71527
