What are the Types of Carob?
Since carob is a tree that has been cultivated in the Mediterranean basin for thousands of years, each producing country has its own local varieties. Rojal, Negra and Duraio in Spain; Mulata and Galhosa in Portugal; Amele and Gibiliana in Italy; Tillyria (Tylliria) in Cyprus are among the most well-known of these varieties. These varieties differ significantly from each other in terms of pod size, sugar content, seed ratio, earliness and disease resistance.
In this article, we introduce the important carob varieties in the world country by country, compare the pod and seed characteristics measured in research, and discuss which criteria stand out in variety selection.
What Does "Variety" Mean in Carob?
Carob (Ceratonia siliqua L.) reproduces by seed in nature, and each tree that comes from seed is genetically different. For centuries, producers have selected trees that produce large and sweet pods or are productive, and have propagated them by grafting. What we call "varieties" today are clones that have been largely selected in this way and propagated by grafting. Tous and Ferguson (1996), who evaluated Mediterranean fruits, state that carob is propagated mainly by eye grafting or pencil grafting on rootstocks grown from seeds.
Therefore, a significant part of the carob varieties are local varieties or village varieties specific to a particular region, rather than internationally registered commercial varieties. According to the compilation by Martins-Loução et al. (2024), Portugal established a gene resource collection of 44 axes in 2013, there is a gene bank in three different locations in Spain, and eleven institutions in France, Greece, Italy and Spain preserve carob material in situ and separately (in situ and ex situ).
The main characteristics that distinguish the varieties are as follows:
- Sex status: female, male or male (hermaphrodite)
- Pod weight, length, width and wall thickness
- Core ratio (share of core in pod weight)
- Sugar content and taste
- Earliness (age to bear fruit) and yield
- Tree strength and crown structure
- Susceptibility to diseases and pests
Varieties of Spain
Spain is one of the countries with the most research on carob varieties. Tous and Ferguson (1996) count Negra, Rojal, Matalafera and Duraio as important varieties of Spain.
In a trial carried out in Catalonia in dry conditions (about 500 mm of rainfall) and covering 18 years after grafting, four Spanish varieties were compared (Tous et al., 2009):
| Kinds | Average pod weight | Core ratio | Feature spotlight |
|---|---|---|---|
| Rojal | 18.9 g | %11,8 | The largest pod, the earliest |
| Duraio | 16.2 g | %17,3 | Highest cumulative core yield (95 kg per tree) |
| Banya de Cabra | 15.3 g | %15,2 | Intermediate |
| Matalafera | — | — | Lowest tree strength |
In the same study, the gum content of the seed (over dry weight) was found to be highest in Duraio (56.9%) and lowest in Rojal (54.1%); the researchers evaluated Duraio as the best performing female variety for new gardens. In cumulative pod production, no significant difference was found between the varieties.
This table shows well why the choice of variety in carob depends on the intended use: While Rojal stands out for pulp products such as flour, powder and broken with its large and fleshy pods, Duraio is advantageous in terms of gum raw material with its higher seed ratio.
Portuguese Varieties
The Algarve region of Portugal is one of the world's important carob production centers. Tous and Ferguson (1996) highlight Mulata and Galhosa as Portuguese varieties. In a study in which 13 Portuguese and 2 Spanish varieties were examined in the Algarve for seven years (1997–2003), it was stated that most of the grafted trees in the region consisted of the Mulata variety, with Galhosa coming in second place (Barracosa et al., 2007). The researchers warned that such a concentration on a single variety threatens regional biodiversity.
In the same study, it was observed that the bean yield varied widely according to the cultivars: Canela had the highest average bean yield (18.14%), followed by Alfarroba Burro (16.57%) and Pé Curto (14.73%), with the lowest value measured in Lagoinha (10.85%). Other Portuguese cultivars studied also include Costela Canela, Costela Vaca, Brava Lagoa, Spargale, Costa Loulé, Gasparinha, and Aida (Barracosa et al., 2007).
Mediterranean varieties compared in Spain
Ten varietal trials comparing six Spanish (A-19, Bugadera, Gastor-1, Gaucin-1, Sayalonga, Rojal), three Portuguese (Aida, Galhosa, Mulata) and one Italian (Albarcara) cultivars in northeastern Spain are valuable in terms of seeing different country cultivars in the same conditions (Tous et al., 2008). The findings are summarized as follows:
- Rojal and Mulata produced the largest pods (over 20 g), but the nucleus ratio of these two varieties remained in the lowest group (10–12%).
- The smallest pods were seen in Gaucin-1 (13.0 g) and Alcarcara (14.1 g); on the other hand, the nucleus proportion was highest in Gaucin-1 with 14.8% and in Albercara with 20.6%.
- In Albarcara and Aida, the cumulative seed yield exceeded 33 kg per tree.
- Aida, Rojal and A-19 were the earliest varieties.
- The researchers recommended Aida, Albarcara, Galhosa, Gaucin-1 and Mulata for the new gardens.
These results indicate that there is often an inverse relationship between pod size and kernel ratio in carob. Martins-Loução et al. (2024) also point out a negative relationship between pulp and kernel content.
Italy, Cyprus, Greece and Other Countries
Italy
Tous and Ferguson (1996) count Gibiliana and Amele as important Italian varieties. Castello et al. (2023), who compiled carob diseases in Italy, mention Amele di Bari among powdery mildew-resistant varieties.
Cyprus
Cyprus has historically been one of the important centers of carob production and export. Tous and Ferguson (1996) refer to Tylliria as the Cypriot variety. Kyratzis et al. (2021), who examined carob gene resources in Cyprus on 124 trees in nine agro-environmental regions, state that the common and dominant local variety on the island is "Tillyria" and "Kountourka" on the Karpaz peninsula; other local types such as "Apostolika", "Mavroteratsia" and "Koumpota" are also mentioned in the introduction of the study. In the same study, the average pod weight was measured as approximately 17 g, length of approximately 15 cm, and width of approximately 23 mm; genetic diversity was found to be low in the grafted material. It was found that characteristics such as core/pod ratio, pod width and thickness were mainly under genetic control, while phenolic substance and tannin content were mostly affected by the growing region.
Greece, Tunisia and California
Tous and Ferguson (1996) count Hemere as the Greek variety, Sfax as the Tunisian variety, and Santa Fe as the variety developed in California.
Balearic Islands
In Spain's Balearic Islands, local varieties are being experimented with in marginal conditions. In a trial where 13 local varieties were grown in a low-rainfall landscape without any inputs, the hermit varieties H-2-12, sa llebre, and Lloseta entered production in the fifth year and yielded the best results. In terms of yield, Granja (over 19%), H2-12 (over 16%), and Bugadera (over 15%) stood out (Barceló et al., 2023).
Male, Female and Male Varieties
Carob is mostly a separate sexual tree; however, there are also hermit varieties (bearing both male and female organs). Martins-Loução et al. (2024) state that hermaphroditic varieties are found especially on the east coast of Spain. Since hermit varieties are self-pollinating, they can also reduce the need to plant male trees in the garden; Santa Fe, developed in California, is also described as a self-fertile variety (Coit, Fruit Varieties and Horticultural Digest).
Pollinator trees are required in gardens established with female varieties. Tous and Ferguson (1996) state that in new gardens, one male or male tree is recommended for every eight female trees, while in traditional gardens, male branches are grafted on female trees. In Spanish variety trials, approximately 12% of the gardens were composed of pollinator trees (Tous et al., 2008; 2009).
It is reported that sexual status may also be related to disease susceptibility. Erbaş (2024) states that some hermad varieties tested in Spain were found to be more susceptible to aphids than female varieties.
Varieties in terms of disease susceptibility
Variety selection is an important protection tool in cultivation without pesticides or with few inputs. In the review of Castello et al. (2023) against powdery mildew:
| Status | Varieties |
|---|---|
| Those described as resilient | Rojal, Matalafera, Amele di Bari, Racemosa |
| Those defined as susceptible | Negra, Melera, Saccarata |
This information is based on observations in Italian and Spanish conditions; it should be noted that disease pressure may vary in different climates.
What to Consider When Choosing a Variety?
There is no "best variety" in carob; there is the most suitable variety for the purpose of use and the region. The findings in the sources point to the following general principles:
- If pulp products such as flour, powder and broken are targeted, varieties with large and fleshy pods come to the fore.
- If seed and gum raw materials are targeted, varieties with high seed content are advantageous.
- Varieties that are adapted to the local climate are usually a safer start.
- Sufficient pollinator trees or hermaphrodites should be planned in the garden.
- Over-reliance on a single variety can be a disadvantage in terms of both biodiversity and disease risk.
Local carob types in Turkey and the research carried out on this subject are the subject of a separate article. To put it briefly, in a study conducted in Antalya, it was reported that the local "Etli" and "Samos" genotypes were superior to the wild genotype in terms of pod characteristics, and the wild genotype was better in terms of seed characteristics (Gübbük et al., 2010).
Frequently Asked Questions
What are the most well-known carob varieties in the world? Rojal, Negra, Matalafera and Duraio in Spain; Mulata and Galhosa in Portugal; Amele and Gibiliana in Italy; Tillyria in Cyprus are the most frequently mentioned varieties.
Are varieties with large pods always better? Studies have shown that large pod varieties often have a lower seed ratio. The appropriate variety varies depending on the targeted product.
What is the advantage of the hermaculous carob variety? Since hermaden varieties can pollinate themselves, they can reduce the need for separate male trees.
Why is core ratio important? The kernel is the raw material of the carob gum. Varieties with a high kernel ratio are more valuable in terms of gum production.
The Right Raw Material with Carob Türkiye
The differences between carob varieties are also reflected in the characteristics of the product obtained at the end: Fleshy pods stand out for pulp products, pods with a high core ratio for gum raw material. At Carob Türkiye, we supply carob fruit, crumbs, flour/powder, seeds and extracts.
For more information about the kernel What is Carob Seed? You can read our article, Carob Seed and Carob Fruit You can review our product pages. For your wholesale and export requests Contact Now You can contact us on our page.
Domestic resources
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