Sicilian sprouting black broccoli: advancing valorization strategies and product innovation

The Brassicaceae family, commonly known as the cruciferous family, encompasses a wide range of herbaceous, annual, and perennial plants widespread around the world. Broccolo nero (Brassica oleracea L. var. italica), is a Sicilian sprouting black broccoli, grown in two towns located on the slope of Mt. Etna Sicily, Adrano and Biancavilla. It is distinguished by distinctive morphometric traits, including the absence of plant apical dominance, young shoots, and small inflorescences. Additionally, the stem, leaves, and inflorescences are characterized by the presence of anthocyanin compounds, contributing to its typical dark violet colour. Broccolo nero can be grown in either a polyannual or annual growing cycle and can be propagated by cuttings in addition to the conventional method of using seeds. The annual crop cycle focuses on producing reproductive shoots, which include tender leaves and flowering inflorescences, typically harvested from January to March, while the polyannual cycle begins similarly to the annual cycle. However, after the harvest of the reproductive shoots, the plant is allowed to flower. During autumn and winter, the leaves become much more tender and sweeter than in summer. The average yield of Sicilian black broccoli is approximately 3 kg year-1 in terms of 30-cm bunches of flowered or vegetative shoots for the annual growing cycle and 15 kg year-1 for the perennial one. Moreover, several scientific studies have highlighted the high content of potentially health-promoting compounds, as glucosinolates (GLSs), polyphenols, ascorbic acid, and vitamins. Notably, the Sicilian black broccoli exhibits a distinctive GLSs profile, primarily comprising glucoraphanin (GRA) at 41%, gluconapin (NGBS) at 55%, and derivatives constituting 4%. Broccolo nero holds significant culinary and nutritional value, serving as a versatile ingredient in various dishes, salads, juices, and fresh preparations. Its use in pre-packaged or minimally processed foods further enhances its culinary applications. Additionally, its abundance of health-promoting antioxidant properties, as demonstrated by numerous studies, makes it a valuable asset in the prevention of chronic-degenerative human diseases.