Bioplastic and New Materials from Carob
The search for alternatives to fossil-based plastics makes plant raw materials valuable again in terms of materials science. Carob is a remarkable plant in this respect: The gum obtained from its seed is a natural polymer, the fruit flesh is a raw material rich in sugar, and the by-products produced during processing are a source of fiber and tannins. These components; It is being investigated in areas such as coatings, adhesives, hydrogels and biofuels.
In this article, we discuss why carob is of interest in terms of bio-based materials, which components are evaluated in which applications, R&D trends in this field, and realistic limits in the transition from laboratory to market, based on sources.
What is Bioplastic and Biobased Material?
Although the term "bioplastic" is frequently used in everyday language, it actually covers two different properties. A material raw material can be "biobased" because it is of plant or biological origin; it can be "biodegradable" because it can be broken down by microorganisms in nature; or it can be both. Not all biobased materials are biodegradable, and not all biodegradable materials are biobased.
Natural polymers such as vegetable polysaccharides, i.e. starch, cellulose and various gums, are the raw material for a significant part of research in this field. These polymers can interact with water, form films when dry, and can be combined with other substances to form materials with different properties. Gum, derived from carob seeds, is also a member of this natural polymer family.
In this article, the concept of "bioplastic" in a broad sense; We consider them as bio-based materials that can replace or complement plastic and similar synthetic materials.
Why Does Carob Attract Attention?
The value of carob in terms of material research comes from the fact that its different parts offer different types of raw materials:
| Carob section | The raw material it offers | Explored use |
|---|---|---|
| Nucleus endosperm | Galactomannan (carob gamut) | Coating, adhesive, film, hydrogel |
| Fruit flesh | Soluble sugars | Bioethanol, sugar platform |
| Fruit powder and processing by-products | Fiber, shell, pulp, polyphenols | Biocomposite filling, active packaging, hydrogel, biofuel |
| Leaf and bark | Tannin | Leather tanning, dyeing |
| Wood | Hard and durable wood material | Building, furniture, marquetry |
The comprehensive review by Martins-Loução et al., published in the journal Plants in 2024, discusses in detail the possibilities of utilizing these different components of carob. According to the review, carob waste can be used as a sugar platform for biofuel or as a soil improver, leaf tannins in leather tanning and dyeing, and wood in building and furniture.
In Turkey, the wide use potential of carob in industry has been emphasized at the official level. In the statement of the Ministry of Agriculture and Forestry in 2020, plastic is also counted among the industrial areas where carob is used.
Galactomannan: From Natural Polymer to Coating and Adhesive
Carob gum is known as a thickener in food with the code E410. However, the same polymer is also considered as a material outside of food. The compilation by Martins-Loução et al. counts adhesives and coatings among the non-food uses of carob gum.
Galactomannans are of interest in this area because they form viscous solutions when dissolved in water and can leave a thin layer when dry. This property forms the basis for thin films covering a surface or adhesives that bond two surfaces, for example. A similar use is seen in history: according to sources about the carob mill in Cyprus, some of the processed products were turned into pellets used to make glue.
Edible films from the carob gamut
Studies on carob gum (LBG) based films have also been carried out in Turkey. In a study published in the Turkish Journal of Chemistry in 2004, LBG films to which polyethylene glycol (PEG) was added as a plasticizer were examined. As the amount of PEG and molecular weight increased, the turbidity of the films increased, and their light transmittance, tensile strength and elongation decreased; the most suitable plasticizer among those examined was determined as PEG 200. In the same study, it was reported that LBG did not melt and remained stable up to 300 °C (Aydinli et al., 2004).
The properties of pure gum films can be improved by combining them with other polysaccharides. In the study of Kurt, Toker, and Törnük (2017), the synergy between xanthan gum and LBG was utilized; in the optimum formulation containing 89.6 percent LBG, 10.4 percent xanthan and 20 percent glycerol, tensile strength was measured as 86.97 MPa and elongation at break was measured as 33.34 percent. The authors report that the two polymers interact harmoniously and improved properties are obtained for biodegradable films and coatings. These results are laboratory scale; additional tests are required for commercial packaging.
Biocomposites from Shell, Pulp and Powder
In bioplastics research, carob is used not only as a gum, but also as a filler as ground fruit powder or processing waste:
- PVA hydrogel film: In a study conducted at Bursa Technical University, 5, 10, and 20 percent carob fruit powder by weight were added to polyvinyl alcohol films; the best tensile strength and elongation were achieved with a contribution of 10 percent, and swelling and moisture content decreased as the dust content increased (Mutlu & Eroğlu, 2025).
- Starch bioplastic: Carob powder was added to thermoplastic films produced from potato peel starch at a rate of 2–15%, and a strong adhesion was observed between the filler and the matrix (Guemmour et al., 2024).
- Biochar filler: Biochar produced from carob waste from glucose extraction was added to the biodegradable PBAT polymer at a rate of 10 and 20 percent; according to the authors, it showed a delaying effect on the polymer's degradation by light (Infurna et al., 2022).
Hydrogels are also part of this field. The compilation by Martins-Loução et al. mentions a funded project aimed at transforming carob by-products into hydrogels for sustainable agriculture. The development of water-saving materials from the by-products of a drought-tolerant tree is a meaningful example of a circular economy.
Active Packaging: Protective Coatings with Carob Ingredients
The polyphenols and volatile components of carob are also being investigated to add antioxidant properties to the packaging. In a study examining extracts prepared from carob kibble, seeds and leaves, the strongest antioxidant effect was seen in the seed extract; no substance migration was detected in the migration test in the active films obtained by adding this extract to the adhesive of a cellulose-based multi-layer film (Ouahioune et al., 2022). In another study conducted in Cyprus, a polyphenolic coating was developed from carob fruit residues; it was reported that the coating reduced lipid oxidation in salmon fillets stored in cold (Goulas et al., 2019).
Sugar, Wood, and Tannins: Other Ingredients
Carob fruit flesh is rich in natural sugars, which can be converted into biobased products by fermentation. Martins-Loução et al.'s compilation counts bioethanol among the technological and biotechnological applications related to carob and states that carob waste can be considered as a "sugar platform" for biofuel production. GRIN-Global, the U.S. Department of Agriculture's database of plant genetic resources, also lists alcohol, firewood, and charcoal among the economic uses of carob. A "sugar platform" refers to the ability of vegetable sugars to be a starting material for chemicals such as bioplastic building blocks as well as fuel.
The wood and tannins of the tree have been used as materials for centuries:
- Wood: Can be used in building and furniture; According to the Val Rahmeh Botanical Garden, its reddish wood was used in marquetry in southern France in the 19th century.
- Tannin: Leaf tannins can be used in leather tanning and dyeing. Historical sources in Cyprus state that the grain obtained from the bark and leaves was used especially in sail dyeing.
These traditional uses show that the carob tree can be evaluated almost entirely.
R&D Trends: Publications and Patents
Scientific and technological interest in carob has increased significantly in recent years. According to the compilation of Martins-Loução et al., 54 percent of the publications on carob are related to technological and biotechnological applications, and 35 percent of these publications consist of patent records. Its application areas range widely, including pharmaceuticals, food, and bioethanol.
In Turkey, the potential of carob in new areas is also being discussed. In the statements made in Alanya in 2025, it was stated that the Carob Workshop evaluated the potential of the product in many areas from agriculture to trade, from food to cosmetics.
A Realistic View: From Lab to Market
While the excitement about bioplastics and new materials from carob is understandable, a realistic assessment is necessary. Many applications in this area are still in the research stage, and there are hurdles to overcome to achieve commercial scale:
- Cost: It is not easy for biobased materials to compete with fossil-based plastics in terms of price.
- Raw material priority: Carob gum and sugars are valuable food raw materials; the use of by-products is more prominent for material production.
- Performance: The water resistance and mechanical properties of natural polymer-based materials require improvement for many applications.
- Scale: Applying a method that is successful in the laboratory on an industrial scale requires a separate engineering process.
- Supply: According to Martins-Loução et al., carob cultivation in the Mediterranean has decreased by 65 percent in the 21st century; raw material continuity is an important issue in this respect.
Therefore, instead of assertive titles such as "plastic from carob", it is more accurate to say that carob components are among the promising raw materials in biobased materials research.
Opportunities for Turkey
The fact that the LBG film, xantane-LBG film and PVA-carob powder studies mentioned above were carried out by Turkish researchers shows that there is a domestic accumulation in this field. In the statement of the Ministry dated 2020, it was stated that the demand of factories processing carob has increased; increased processing capacity means more by-products, therefore more opportunities for the utilization of shell, pulp and fiber.
Frequently Asked Questions
Can plastic be made from carob?
Edible films from the carob gamut, starch from fruit powder and PVA-based biocomposites were produced in the laboratory. However, these applications are in the research phase; it is too early to talk about common commercial carob-based plastic products.
Where is carob gamut used as a material?
Other than food, it is used in adhesives and coatings; it is being investigated for edible and biodegradable films by combining it with other polysaccharides such as plasticizers or xananthans.
What can carob by-products be made into?
Its evaluation is being explored in areas such as sugar platform for biofuel, soil amendment and hydrogels for sustainable agriculture.
What is the share of patents in carob research?
According to a 2024 review, 54 percent of carob publications are related to technological and biotechnological applications; 35 percent of these are patent registrations.
The Raw Material of the Future with Carob Türkiye
Carob is a plant that offers hope for new materials and sustainable technologies beyond traditional food uses. The realization of this potential is possible with regular, traceable and quality raw material supply.
As Carob Türkiye, we supply carob fruit, crumbs, flour/powder, seeds and extracts. For your raw material needs for R&D projects and industrial applications Our Products page, for raw materials for gamut production Carob Seed You can take a look at our page. For your wholesale and export requests Contact Now You can contact us on our page.
Domestic resources
Anadolu Agency / Habertürk, "Ministry of Agriculture and Forestry made a call for investment for carob production", 11 December 2020. haberturk.
com/ AGRICULTURE- and- forest- Ministry- Carob- production... Economy Newspaper, "Carob harvest festival in Alanya", 9 September 2025. economy newspaper.
com/ cities/ In Alanya- Carob- harvest- s… Aydinli, M., Tutas, M., Bozdemir, O. A., "Mechanical and light transmittance properties of locust bean gum based edible films", Turkish Journal of Chemistry, 28(2), 163–171, 2004. avesis.
Mediterranean. edu. en/ PUBLICATION/ E2710250- 24f6- 4bf8- A7A4- 5a3d4... Kurt, A., Toker, Ö. S., Törnük, F., "Effect of xanthan and locust bean gum synergistic interaction on characteristics of biodegradable edible film", International Journal of Biological Macromolecules, 102, 1035–1044, 2017. doi.
org/ 10. 1016/ j. ijbiomac. 2017. 04. 081 Mutlu, B., Eroğlu, M., "Incorporation of carob pod powder on polyvinyl alcohol-based biocomposite hydrogel film", Journal of Polymer Research, 32(10), 2025. doi.
org/ 10. 1007/ S10965- 025- 04590- y Foreign sources
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 USDA ARS GRIN-Global, "Ceratonia siliqua" (economic uses). npgstest.
ars- grin. gov/ gringlobal/ taxon/ taxonomydetail?id=... Jardin Botanique Val Rahmeh (MNHN), "Ceratonia siliqua – carob". jardinbotaniquevalrahmehmenton.
fr/ it/ node/ 3952 Andrews, R., "The Black Gold of Cyprus", Hampshire Mills Group Newsletter 123, 2018. Hampshiremills.
org/ Newsletters/ 123%20Winter%2018%20Newsle... History of Limassol, "The change of carob mill in the center of Limassol from then until now", All About Limassol. allaboutlimassol.
com/ en/ the- change- of- carob- mill- in- the- c… Guemmour, H., Kheffache, D., Khier, N., "Sustainable starch-based bioplastics reinforced with carob filler: characterization and biodegradability assessments", International Journal of Polymer Analysis and Characterization, 2024. doi.
org/ 10. 1080/ 1023666X. 2024. 2377648 Infurna, G., Botta, L., Maniscalco, M., Morici, E., Caputo, G., Marullo, S., D'Anna, F., Dintcheva, N. T., "Biochar Particles Obtained from Agricultural Carob Waste as a Suitable Filler for Sustainable Biocomposite Formulations", Polymers, 14(15), 2022. doi.
org/ 10. 3390/ polym14153075 Ouahioune, L. A., Wrona, M., Becerril, R., Salafranca, J., Nerín, C., Djenane, D., "Ceratonia siliqua L. kibbles, seeds and leaves as a source of volatile bioactive compounds for antioxidant food biopackaging applications", Food Packaging and Shelf Life, 31, 100764, 2022. doi.
org/ 10. 1016/ j. FPSL. 2021. 100764 Goulas, V., Hadjivasileiou, L., Primikyri, A., Michael, C., Botsaris, G., Tzakos, A. G., Gerothanassis, I. P., "Valorization of carob fruit residues for the preparation of novel bi-functional polyphenolic coating for food packaging applications", Molecules, 24(17), 3162, 2019. doi.
Scientific Resourcesorg/ 10. 3390/ molecules24173162
