Shallots are a perennial plant from the Alliaceae family, classified with the common onion under the name of the Allium cepa Aggregatum group. The term shallot is also used for diploid and triploid viviparous onions, known as Allium × proliferum (Moench) Schrad and Allium × cornutum Clementi ex Vis., respectively. In this study, we compared the dry matter, pyruvic acid content, sugar content, flavonoid content, antioxidant capacity and mineral composition of 34 shallot accessions falling into three shallot species (Allium × cornutum, Allium × proliferum and A. cepa Aggregatum). Shallot accessions belonging to the A.× cornutum and A. × proliferum groups are characterized by high dry matter content (around 25%), of which a little less than 50% is formed of inulin-type sugars, polysaccharides, considered an excellent prebiotic with beneficial effects on human health. On the other hand, accessions belonging to the A. cepa Aggregatum group have lower dry matter content and, as a result, lower pungency (measured as pyruvic acid content), making them more suitable for fresh consumption by a broader range of consumers, but, at the same time, abundant in phenolic compounds, especially quercetin and isorhamnetin glycosides. We also observed a greater biodiversity among accessions within the A. cepa Aggregatum group in all the analyzed physico-chemical parameters compared to the other shallot groups. The investigated shallot accessions have an excellent in vitro antioxidant capacity, as well as excellent nutritional properties.

Sauerkraut is produced by cabbage fermentation either spontaneously or by adding lactic acid bacteria. Although commercial cabbage cultivars are more desirable due to their higher yield and uniformity, traditional cultivars are highly prized for their unique sensory characteristics and suitability for fermentation. The aim of this study was to investigate the properties of sauerkrauts from traditional cabbage cultivars (‘Brgujski’ and ‘Žminjski’) compared to commercial samples, and to unravel the effects of ambient (18 °C) and cold storage (4 °C) on sauerkraut properties. Higher total phenolic contents and total antioxidant capacities measured by both FRAP and DPPH methods were observed for sauerkrauts from traditional cultivars. In total, 32 volatile compounds were identified, and differences in the volatile profile were observed among the investigated sauerkrauts. The sensory properties of traditional cabbage cultivars were on par, or even better, compared to those of commercially available sauerkraut products. The cold storage conditions characteristic of commercial environments preserved the total antioxidant capacity, the red to green color ratio (a), as well as the lightness (L) of sauerkraut compared to the ambient temperatures characteristic of domestic conditions, indicating the preservation of bioactive compounds responsible for the purple cabbage head coloration of the investigated traditional cultivars.

The aim of this study was to define optimal harvesting date of garlic cv. 'Istarski crveni' by comparing the amount of volatile compounds as one of quality indicators. In total 17 volatile compounds were determined in tested garlic samples by headspace solid-phase microextraction coupled to gas chromatography with flame ionization and mass spectrometric detection (HS-SPME-GC-FID-MS) regardless of harvesting date. Major volatiles diallyl trisulfide, diallyl sulfide, methyl allyl disulfide and diallyl disulfide representing 98.5 % of all the determined compounds have shown no significant difference between harvest dates. Significantly higher content of the two minor volatiles, allyl mercaptane and thieno[2,3-b]thiophene, was found in the last and second when compared to the first harvest date. Principal components PC1 and PC2 explained 78% of the total variance and pointed to certain relations between harvest dates and volatiles. The technological maturity had probably been reached at the first harvesting date since similar amounts of volatiles were found during the observed period.

Preservation of plant genetic resources has become crucial for agricultural sustainability, particularly for vegetatively propagated crops like garlic. Modern agricultural practices, monoculture farming, environmental degradation, and climate change have led to genetic erosion, and there is growing interest in traditional garlic varieties, which may harbor superior traits. Despite being an asexually propagated crop, garlic exhibits a diverse range of ecotypes in phenotypic and agronomic characteristics. This study analyzed 77 garlic accessions from Istria and Kvarner, Dalmatia, Continental Croatia, and other countries, examining morphological traits alongside biochemical properties, namely allicin content, total phenolic content (TPC), and antioxidant capacity (with ferric reducing antioxidant power (FRAP) assay, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay). Morphological analysis categorized the accessions into two distinct morphotypes, which did not differ significantly in any biochemical parameter. In contrast, accession provenance was associated with differences in TPC and FRAP, with the highest values in accessions from Istria and Kvarner; in 2018/2019, these reached 820.8 mg GAE/100 g DW (TPC) and 354.6 µmol TE/100 g DW (FRAP), significantly exceeding Continental Croatia (494.1 and 180.4, respectively). This regional pattern varied between the two vegetation years. DPPH and allicin content instead differed between the two vegetation years, with DPPH increasing markedly from 2018/2019 to 2019/2020 (from 358.1 to 892.2 µmol TE/100 g DW in QlG1 and from 380.6 to 836.3 µmol TE/100 g DW in QlG2). These results indicate that, in this collection, morphotype was not a reliable predictor of biochemical quality in garlic and underscore the importance of combining morphological and biochemical assessment in germplasm conservation and breeding programs.