Characterization of commercial cultivars of artichoke, cardoon and their wild relatives for their productive and commercial optimization
- Autores: Marina Giménez Berenguer
- Directores de la Tesis: Pedro Javier Zapata Coll (dir. tes.), Maria José Giménez Torres (codir. tes.), Salvador Castillo García (tut. tes.)
- Lectura: En la Universidad Miguel Hernández de Elche ( España ) en 2025
- Idioma: español
- Tribunal Calificador de la Tesis: Daniel I. Leskovar (presid.), María Teresa Pretel Pretel (secret.), Francisco Artés Hernández (voc.)
- Programa de doctorado: Programa de Doctorado en Recursos y Tecnologías Agrarias, Agroambientales y Alimentarias por la Universidad Miguel Hernández de Elche
- Materias:
- Texto completo no disponible (Saber más ...)
- Resumen
This doctoral thesis, titled "Characterization of Commercial Cultivars of Artichoke, Cardoon, and their Wild Relatives for Productive and Commercial Optimization", provides a comprehensive investigation into the genetic, agronomic, and environmental factors influencing the quality and commercial potential of artichokes (Cynara cardunculus var. scolymus) and cardoons (Cynara cardunculus var. altilis). These species, which belong to the Asteraceae family, are economically significant crops in Mediterranean agriculture, valued not only for their culinary applications but also for their high nutritional and bioactive compound content. Despite their agronomic importance and increasing interest in their health-promoting properties, artichokes and cardoons remain relatively underexplored compared to other vegetable commodities. The characterization of their biochemical, physiological, and post-harvest properties is crucial for enhancing their competitiveness, optimizing their industrial applications, and ensuring their sustainability within modern agricultural systems.
Artichokes and cardoons play a crucial role in Mediterranean agriculture. Spain, Italy, and Egypt are the leading producers of artichokes, with Spain ranking third worldwide. The artichoke industry is particularly relevant in the Valencian Community and Murcia, where it contributes significantly to local economies. Artichoke cultivation follows both annual and perennial production systems, with vegetative propagation being the dominant method in traditional farming. However, seed-propagated cultivars have gained interest due to their potential advantages in terms of uniformity, yield, and disease resistance.
Cardoons, on the other hand, are less commonly consumed as vegetables but hold significant agronomic value due to their adaptability to marginal lands and their tolerance to drought and extreme temperatures. They are cultivated mainly in Mediterranean countries, where they are used in traditional cuisine, functional food applications, and as a source of bioactive compounds. Moreover, cardoon cultivation has been associated with soil health benefits, such as enhanced organic matter and improved microbial activity.
Both artichokes and cardoons are highly regarded for their bioactive composition. Artichokes are particularly rich in polyphenols, including chlorogenic acid, cynarin, and flavonoids, which contribute to their strong antioxidant capacity. These compounds not only enhance the nutritional value of artichokes but also play a role in determining their post-harvest stability and processing suitability. Similarly, cardoon seeds have been identified as a valuable source of minerals such as calcium, magnesium, and potassium, making them a promising ingredient for functional food and feed applications.
Despite their well-documented nutritional and agronomic benefits, both artichokes and cardoons face several research gaps that limit their commercial and productive optimization. In the case of artichokes, post-harvest browning due to enzymatic oxidation remains a significant challenge for fresh-cut processing. While polyphenols are essential for their antioxidant properties, they also act as substrates for polyphenol oxidase leading to rapid discoloration and reduced consumer acceptability. This balance between nutritional quality and post-harvest stability is crucial in determining the suitability of different cultivars for fresh or processed markets. For cardoons, research has primarily focused on their agronomic traits and medicinal properties, while fewer studies have explored the stability of their mineral composition across different genotypes and growing conditions. Understanding these variations is essential for optimizing cardoon seed utilization in food, feed, and industrial applications.
This doctoral thesis aims to address these knowledge gaps by providing a comprehensive characterization of artichoke and cardoon cultivars, focusing on their genetic, biochemical, and post-harvest properties. Through six interconnected studies, this research aims to deepen the understanding of the productive and commercial aspects of these crops, addressing key challenges related to fresh-cut processing, post-harvest quality, environmental stress tolerance, and cardoon seed nutritional composition. By integrating physiological, biochemical, and agronomic perspectives, this thesis offers valuable insights that contribute optimizing production strategies, improving post-harvest management, and enhancing the competitiveness of these crops in agricultural and industrial sectors.
The first set of studies focuses on fresh-cut artichokes, investigating enzymatic browning, phenolic content, and storage stability. A novel approach combining L-cysteine and essential oils (eugenol, thymol and carvacrol) at an equivalent concentration of 75, 150 and 300 µL, was evaluated for its efficacy in minimizing enzymatic browning while preserving the bioactive properties and sensory attributes of 'Blanca de Tudela' fresh-cut artichokes. Results of the application of cysteine and 150 µL of EOs, confirmed a significant reduction in oxidative browning, extending shelf-life and improving visual quality without compromising phenolic retention.
Further research examined the suitability of three artichoke cultivars ('Lorca,' 'Tupac,' and 'Green Queen') for fresh-cut processing, with particular emphasis on the influence of flower head order (main, secondary, tertiary). Results demonstrated that tertiary heads, particularly from the 'Green Queen' cultivar, exhibited the highest phenolic content but also showed greater susceptibility to browning. In contrast, main heads, characterized by lower polyphenol levels, especially in the 'Lorca' and 'Tupac' cultivars, displayed reduced browning indices and higher consumer acceptability. A strong negative correlation coefficient was observed between these parameters, indicating that increased browning directly reduces sensory appeal. This study underscores the significance of cultivar selection and flower head order in optimizing the quality and commercial capability of minimally processed artichoke products.
Following this line of investigation, Lorca cultivar was selected for its viability as minimally processed product. Artichokes were classified according to the flower head orders (main, secondary, and tertiary) and three internal development stages (initial, intermediate, and advanced). For the first time, internal development stage was analysed in relation to total phenolic content. The results indicated that main heads and those in the advanced development stage exhibited the lowest phenolic concentration and PPO activity, resulting in reduced browning susceptibility, and therefore, potentially enhancing its suitability for fresh-cut processing.
Another core investigation conducted a phytochemical characterization of artichoke heads based on their position on the plant (main, secondary, and tertiary heads) and harvest date throughout an entire growing season in 'Blanca de Tudela' artichoke cultivar. The results indicated that tertiary heads exhibited the highest total identified polyphenol concentration, primarily due to their elevated levels of hydroxycinnamic acid and luteolin derivatives compared to secondary and main heads. Furthermore, two postharvest storage experiments were conducted using main, secondary, and tertiary artichoke heads harvested in winter and spring. Tertiary heads demonstrated the lowest weight loss, minimal firmness reduction, and the lowest respiration rate during cold storage, which may be attributed to their higher antioxidant compound content. In conclusion, tertiary heads exhibit greater suitability for low-temperature storage from harvest to consumption, as they maintain quality attributes for a longer period and contain higher levels of bioactive compounds.
Expanding on this research, the following study explored the role of phenolic compounds and antioxidant activity in mitigating frost damage in 'Blanca de Tudela' artichokes. In northern hemisphere countries, artichoke harvesting takes place during the winter months, exposing the crop to low temperatures. This exposure can lead to frost injury, manifested as cuticle blistering and detachment of the outer bracts, which may subsequently develop brown or black discoloration. Such injuries can result in significant economic and production losses. However, to the best of our knowledge, no previous studies have specifically addressed this issue in artichokes. Several parameters were analysed, including flower head order, weight and size of the artichokes, total phenolic content, phenolic profile, and total antioxidant activity. The results indicated that tertiary heads, which are the smallest in size, contained the highest levels of total phenolic compounds and antioxidant activity. Consequently, these characteristics provided enhanced protection against frost damage. Conversely, larger artichokes, particularly primary heads, were more susceptible to frost injury. These findings suggest that a well-developed antioxidant system, characterized by elevated phenolic content, plays a key role in reducing artichoke susceptibility to frost injury.
Beyond artichokes, this thesis also evaluates the variations in mineral composition and ash content of thirteen distinct genotypes of cultivated and wild cardoon seeds (four commercial, four wild, and five self-developed genotypes from the University of Catania) over three consecutive growing seasons. The findings revealed that ash content, as well as macro- and micro-element concentrations, were significantly influenced by environmental conditions, genetic factors, and their interactions. Notably, ash content exhibited substantial fluctuations across the three seasons, with the lowest value observed in the second season, likely associated with higher rainfall levels compared to seasons one and three. The self-developed genotypes demonstrated the highest mean concentrations of all micro-mineral elements analysed. Overall, cardoon seeds were confirmed to be a valuable source of essential macro- and micro-elements, with the self-developed genotypes from the University of Catania showing particularly high nutritional potential. This study provides, for the first time, a comprehensive assessment of the long-term consistency and variability in mineral content and ash composition in cardoon seeds, offering new insights into their nutritional value and potential applications.
Collectively, the findings of this thesis contribute to a more comprehensive understanding of artichoke and cardoon quality determinants. Through a multidisciplinary perspective, this research provides practical insights for breeders, growers, and processors seeking to optimize production strategies.
Furthermore, the thesis reveals a fundamental misalignment in artichoke commercialization, where larger main heads, which exhibit lower browning susceptibility, should be prioritized for industrial applications, while tertiary heads, richer in bioactive compounds, should be directed toward fresh consumption due to their potential health benefits. These insights lay the foundation for a paradigm shift in the artichoke industry, promoting a more rational and scientifically guided approach to production, consumption, and processing strategies.
