What is Carob Peel and Where is it Used?
The expression "carob peel" is often used in everyday language for the fleshy, sweet part of the fruit that remains after the seeds are removed. In technical language, when the word "shell" is mentioned, the hard, brown cover surrounding the seed comes to mind. When these two concepts are confused with each other, both the consumer and the raw material buyer may refer to the wrong product.
In this article, we explain these two different structures, known as "shells" in carob, their proportions in the fruit, their composition and where they are used, based on scientific sources.
Why Does the Word "Shell" Cause Confusion?
Carob fruit is in the form of a long pod typical of legumes. When ripe, it turns brown, hardens and takes on the appearance of a shell when viewed from the outside. For this reason, the edible part of the fruit is often called "carob shell" among the people. However, this part is defined as the fleshy part of the fruit, that is, the "pulp", in botanical and industrial language.
On the other hand, the kernels inside the fruit also have their own shells. This seed shell (seed coat, husk, hull or peel in English sources) is the hard outer covering that needs to be peeled off in the production of carob gum. In addition, the bark on the trunk of the tree is another structure and is not the subject of this article.
In summary, when we say "carob shell", three different things can be meant:
| Daily use | Technical equivalent | Basic use |
|---|---|---|
| Fruit peel (edible part) | Pulp of the fruit | Broken, dust, molasses, must, feed |
| Core shell | Seed coat (husk) | A by-product of gamut production |
| Tree bark | Trunk bark | Beyond the scope of this article |
The fleshy part of the fruit: "carob shell" among the people
The fleshy part of the fruit makes up most of the weight of the carob. Antoniou et al. from the Cyprus Agricultural Research Institute (2020) report that the carob fruit consists of approximately 90 percent flesh and 10 percent seeds by weight at full maturity. According to the same study, the fleshy parts (kibble) remaining after the seeds are separated contain about 48–56 percent sugar, about 40 percent crude fiber, 2–7 percent protein, and 0.5–1 percent fat over dry weight.
In a study conducted on carob fruits grown in Anatolia (Ayaz et al., 2007), sugars, amino acids, organic acids, minerals and phenolic compounds were examined in the fruit; sucrose, glucose and fructose were defined as the main sugars of the fruit. The sweet taste of the fleshy part is due to these sugars, and the slightly astringent taste is due to phenolic compounds.
The tannin content of the fleshy part is also remarkable. In the international feed information system Feedipedia, the average total tannin value for seedless carob fruit meal over dry matter is given as 19.9 g/kg. Tannins contribute to the astringent taste of the fruit and are also a considered component in animal nutrition.
Where is the fleshy part of the fruit used?
This part, popularly called "shell", is the raw material for the vast majority of carob products. A study conducted in Cyprus (Papaefstathiou et al., 2018) examining 20 traditional carob products analyzed a wide variety of products such as syrup, powder, carob coffee, carob chocolate, cream, and traditional desserts. This diversity shows how different ways the succulent can be utilized in the kitchen.
The main usage areas can be summarized as follows:
- Direct consumption: Eating dried fruit as a snack
- Broken (granule) and kibble: Presenting to the industry as intermediate raw material
- Flour and powder: Raw or roasted ground, used in pastry and beverages
- Molasses, syrup and must: Products obtained by aqueous extraction and condensation
- Brewing: Drinks prepared by steeping crushed fruit in hot water
- Animal feed: Evaluation of particularly fine fractions and low-quality batches in feed
Antoniou et al. stated that fleshy part fragments were used for a long time mainly as a cocoa substitute in animal feed, confectionery and beverage industries, and as local kitchen ingredients; in recent years, products such as powder, fiber, must and molasses have attracted more attention in the food industry. For details of these products What is Carob Kibble (Granule)? and What is Carob Flour Powder? You can take a look at our articles.
Kernel Shell: The First Hurdle of Gum Production
In technical terms, the structure meant by "shell" is the outer cover of the kernel. According to Medronho et al. (2025), the locust bean kernel consists of three main parts: the shell, the germ and the endosperm. The shell is a hard and brown covering that makes up about 30–35 percent of the dry weight of the kernel. The germ makes up about 15–30 percent of the dry weight, while the endosperm makes up about 40–50 percent.
In the same study, it is stated that untreated kernels absorb more light in the visible light region, and this is due to phenolic compounds such as anthocyanins and tannins, and pigments and molecules such as lignin. The dark color of the kernel shell is also associated with these components.
The most important feature of the kernel shell is that it must be removed in the production of carob gum. In the 2017 report of the European Food Safety Authority (EFSA), it is stated that the kernel shell is very hard and durable, based on industry knowledge, so the kernels are peeled with special processes without damaging the endosperm and germ. According to the report, germ and shell residues remaining in commercial gum preparations can reduce galactomannan content.
How is the Seed Shell Separated?
There are three basic approaches to the separation of the nuclear shell. When the EFSA report and the study of Medronho et al. are evaluated together:
- Acid method: The kernels are heated with sulfuric acid to char the shell, and the residues are removed by washing and brushing.
- Roasting method: The beans are roasted in a rotary oven and the shell separates and falls off; the product becomes slightly darker in color.
- Hot water method: The kernels are kept in boiling water for about an hour, after which the shell is broken apart.
In a thesis study conducted at Süleyman Demirel University (Kıvrak, 2011), it was reported that the gums obtained by these methods showed significant differences in terms of color, protein, ash, foreign particles and viscosity. The choice of method directly affects how cleanly the shell is separated and therefore the quality of the scale. We discuss this process in detail in our article on scale production.
Can Kernel Shell Be Considered a Byproduct?
The fate of the kernel shell largely depends on the peeling method used. In the acid method, the shell is charred and broken down, making it difficult to recover as a separate product. In more moderate methods, it may be possible to collect the shell as a separate fraction.
Scientific interest in this topic is increasing. Medronho et al.'s study was conducted as part of a research project aimed at transforming carob by-products into new hydrogels. The compilation by Martins-Loução et al. (2024) also highlights that carob has high industrial value for its fruit-fleshy part and seeds, but the species is still poorly researched scientifically and has significant knowledge gaps.
Therefore, the most honest thing that can be said today about the uses of the kernel shell is that evaluation options are being investigated, but it does not have an established and widespread market such as the flesh or endosperm. For this reason, it is necessary to approach the health claims attributed to the kernel shell on the Internet with caution.
Using the Right Term in Trading
Correct use of terms in the raw material trade prevents the wrong product order. When a buyer asks for "carob shell", he is most likely referring to pitted pieces of fruit, i.e. broken or kibble. However, for a company working in the gamut industry, "shell" can mean kernel shell. It is therefore recommended to clarify the following at the order and quotation stage:
- Whether the product is the fleshy part of the fruit or the seed shell
- Whole fruit, broken, granular, or powdered form
- Whether raw or roasted
- Part size, moisture and foreign matter expectation
- Intended use (food, beverage, feed, etc.)
Frequently Asked Questions
Can carob bark be eaten?
The part called the shell among the people is the fleshy part of the fruit and is the main edible part of the carob. The seed shell, on the other hand, is not a part that is consumed directly due to its hard structure.
Is carob powder made from the bark?
Carob flour/powder is obtained by grinding the fleshy part of the fruit (colloquially "peel"); it is not made from the kernel shell.
Is the kernel shell found in gum?
It is removed by the peeling process. It is undesirable to remain a residue as it reduces the quality of the scale.
Can tea be made from carob bark?
Drinks prepared by brewing the broken fruit, that is, the fleshy part, are traditionally known. The part used here is not the seed shell, but the fleshy part of the fruit.
Carob Products with Carob Türkiye
The concept of "shell" in carob corresponds to completely different products depending on which part is meant. The fleshy part of the fruit is broken, powdered and used for products such as molasses; the kernel is the source of industrial raw materials such as gum.
At Carob Türkiye, we supply carob fruit, crumbs, flour/powder, kernels, and extracts. Carob Fruit, Carob Kibble (Granular) and Carob Seed You can review our pages, about the core What is Carob Seed? You can read our article. For your wholesale and export requests Contact Now You can contact us on our page.
Domestic resources
Kıvrak, N. E., "Determination of some physical and chemical properties of gum produced from carob seeds using different barking methods", Master's Thesis, Süleyman Demirel University Institute of Natural and Applied Sciences, 2011. I'm hungry.
SDU. edu. en/ handle/ 123456789/ 28782 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 Foreign sources
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 Medronho, B., Boutoub, O., Duarte, H., Aliaño-González, M. J., Guerra, R., Brázio, A., Gonçalves, S., Romano, A., "On the Optimization of Carob Seed Peel Extraction Using Aqueous-Based Acidic Systems", Molecules, 30(7), 1397, 2025. doi.
org/ 10. 3390/ molecules30071397 EFSA ANS Panel (Mortensen, A. et al.), "Re-evaluation of locust bean gum (E 410) as a food additive", EFSA Journal, 15(1), e04646, 2017. doi.
org/ 10. 2903/ j. efsa. 2017. 4646 Papaefstathiou, E., Agapiou, A., Giannopoulos, S., Kokkinofta, R., "Nutritional characterization of carobs and traditional carob products", Food Science & Nutrition, 6(8), 2151–2161, 2018. doi.
org/ 10. 1002/ FSN3. 776 Martins-Loução, M. A., Correia, P. J., Romano, A., "Carob: A Mediterranean Resource for the Future", Plants, 13(9), 1188, 2024. doi.
org/ 10. 3390/ plants13091188 Feedipedia (INRAE, CIRAD, AFZ, FAO), "Carob (Ceratonia siliqua), pod meal, without seeds", table update: 2012. feedipedia.
Scientific Resourcesorg/ node/ 11933
