Mineral and Fatty Acid Composition in Croatian Garlic (Allium sativum L.) Ecotypes

Chemical composition of garlic bulbs is influenced by genotype, agronomic, technological, and environmental factors.

The aim of this study was to determine the mineral and fatty acid composition of garlic bulbs of 27 ecotypes collected in northeast Adriatic region (Croatia). Samples were collected from 21 different locations: Brgud, Golubic, Jezero, Konavle, Kricke, Kurtovici, Ljubitovica, Metajna Pag, Metkovic, Miljevci, Obrovac Sinj, Opuzen, Polaca Knin, Primorski Dolac, Rastok, Stilja, Tinjan, Trnbusi, Vojnic and Zmijavci. Ecotypes Brgud, Konavle, Kurtovici, Ljubitovica (samples Bijeli and Sarac), Primorski Dolac (sample spring), and Rastok and Vojnic had garlic bulbs with more than 40% of dry matter. The lowest bulb dry weight (less than 34.8%) was recorded in samples from Golubic (samples 1 and 2), Metajna, Polaca Knin and Primorski Dolac (sample winter).

The highest bulb N concentration (41.3 g/kg DW) was recorded on location Metajna, while the lowest was on location Miljevci (13.1 g/kg DW). At the same location was recorded the lowest bulb P concentration (4.13 g/kg DW), while the highest was observed in both samples from Opuzen (6.49 and 6.53 g/kg DW). Highest bulb K concentration was recorded on sample Trnbusi 4 winter (15.3 g/kg DW), while the lowest on Brgud (7.3 g/kg DW).

Lowest bulb Cu concentration was recorded on Polaca Knin (0.72 g/kg FW), whereas highest on sample Opuzen winter (4.34 g/kg FW). Highest bulb Zn concentration was recorded on sample Opuzen spring (23.1 g/kg FW), while lowest concentrations (6.9 g/kg FW) were found in Golubic and Kurtovici. Lowest bulb Cd concentrations were found in ecotypes Ljubitovica White and Trnbusi 3 spring (0.06 and 0.09 g/kg FW). At locations Rastok (0.44 g/kg FW), Kozica-Vojnic (0.41 g/kg FW) and Konavle (0.39 g/kg FW) were found the highest Cd concentration in the garlic bulb. Garlic bulbs contained from 29.1 to 69.4 mg/kg DW total fatty acids. Linoleic/alpha-linolenic acid ratio is considered an important dietary factor, and an alpha-linolenic acid-rich Mediterranean diet is recommended. Croatian garlic ecotypes showed great variability, with locations Brgud (5.74), Kricke (5.79) and Golubic 1 and 2 (5.81; 5.88) having the lowest linoleic/alpha-linoleic acid ratios and location Obrovac Sinj the highest (9.46).  The study revealed that garlic bulbs had high levels of nutritionally important components, such as fatty acids and minerals, and that all quality components were strongly influenced by genotype and location.