Polyphenol Oxidase Activity from Three Sicilian Artichoke [Cynara cardunculus L. Var.scolymusL. (Fiori)] Cultivars: Studies and Technological Application on Minimally Processed Production

Abstract

Several papers helped with the development of more methods to control browning, or study thermal polyphenol oxidase (PPO) inactivation, but did not provide any solutions to technological process problems and food process improvement. Artichokes [ Cynara cardunculus L. var. scolymus L. (Fiori)] are susceptible to browning; this alteration could affect and reduce the suitability for its use, fresh or processed. Within this study, the catecholase and cresolase activities of PPO from three different Sicilian artichokes cultivar were characterized with regard to substrate specificity and enzyme kinetics, optimum pH and temperature, temperature and pH stability, and inhibitor test; all of the results were used for technological purposes, particularly to optimize minimally processed productions (ready-to-eat and cook-chilled artichokes).

Polyphenol Composition, Antioxidant, Antimicrobial and Quorum Quenching Activity of the “Carciofo di Montoro” (<i>Cynara cardunculus</i> var. <i>scolymus</i>) Global Artichoke of the Campania Region, Southern Italy

“…The amount of polyphenols was 525 GAEμg/g of product. This result are in agreement with the range observed for other cultivars, such as Green Globe or Violetto di Toscana [7], and higher than other typical Italian artichokes, such as Violetto di Sicilia, Violetto di Provenza, and Tema [17] indicating that "Carciofo di Montoro" could represent another important source of phytochemicals, capable to exhibit therapeutic activity [18]. The content of polyphenols present in such ecotype affected, with all probability, also its antioxidant activity: in fact, the amount of extract needed to inhibit 1 ml of DPPH at 50% was just 4.24 mg, more effective than other artichokes studied, for example, by Velez et al (EC 50 = 9.16 mg) [19] or Menghini (EC 50 of about 15.95 mg) [20], Ferracane et al [21] observed that the cooking process of artichokes in boiling water increased their antioxidant content and activity with respect to raw artichokes, independently of the assay used, stating that the spatial arrangement of the phenolic groups can deeply affect the antioxidant activity of the molecules.…”

Polyphenol profile and content in wild and cultivated Cynara cardunculus L.

“…Lombardo et al (2010) particularly in the floral stem for both caffeoylquinic acids and luteolin derivatives and in the receptacle for apigenin derivatives (Figure 5). Todaro et al (2010) also reported a higher TPC in spring than in winter (on average, 8.1 and 1.5 mg of CAE per g of FM, respectively), in a study carried out on heads of three globe artichoke cultivars.…”

“…The quality loss is due to the browning phenomenon, which occurs through oxidative degradation by polyphenol oxidase or to formation of iron-chlorogenic acid complexes (Lattanzio et al, 1994(Lattanzio et al, , 2009. This phenomenon is especially important in fresh-cut products, post-harvest handling and storage, and represents a limiting factor to processing artichoke for both industrial and minimally processed products (Gimenez et al, 2003;Lattanzio et al, 2003;Todaro et al, 2010;Amodio et al 2011). The food industry, in order to prevent enzymatic browning, have often used synthetic antioxidants, such as butylated hydroxyanisole and butylated hydroxytoluene, acidifying agents and calcium solutions, for extending shelf-life (Choi et al, 2000;Martin-Diana et al, 2007;Rico et al, 2007).…”

Evaluation of ‘Lorca’ Cultivar Aptitude for Minimally Processed Artichoke

“…Enzymatic browning is influenced by many variables which are dependent on the genotype, such as the specific activity of enzymes or the quantity and nature of phenolic compounds [18]. Therefore, cultivars rich in phenolic compounds and with a high enzyme activity are unsuitable for fresh-cut processing [3,19,20]. Several studies have showed that genetic material is a key determinant of phenolics content, antioxidant enzyme activities, and thus, the suitability of artichoke cultivar for fresh-cut processing, which contributes to the overall functional quality of this crop [10,21,22].…”