Non‐volatile cysteine sulphoxides and volatile organosulphur compounds in cloves of garlic (Allium sativum L.) and elephant garlic (Allium ampeloprasum L.) local accessions from northern and central Italy

Abstract

BACKGROUND Garlic (Allium sativum L.) and other species of genus Allium are popular vegetables and food seasonings, owing to their spicy flavour and richness in health‐promoting compounds. Several local garlic types are still grown on a small scale in different Italian regions, not being however yet properly characterized for their chemical composition. RESULTS In the present investigation ten garlic and four elephant garlic (Allium ampeloprasum L.) populations cultivated in northern and central Italy were evaluated for their alk(en)yl cysteine sulphoxide (ACSO) and volatile compound profiles. Three non‐volatile ACSOs (methiin, alliin, and isoalliin) and 27 volatile compounds were identified and quantified. A high and significant within‐type variability was detected, with total ACSOs in the range 2759–5756, 4533–15 520, and 6565–10 643 mg kg−1 of fresh weight (f.w.). in elephant, white and red garlic, respectively. Elephant garlic showed a total sulphoxide content and a relative alliin amount significantly lower than white and red garlic. Remarkable within‐type differences were also assessed for volatile compound content, ranging 260–599, 333–981, and 618–845 mg kg−1 f.w. in elephant, white, and red garlic, respectively. Diallyl trisulphide was the major individual compound, accounting for more than 0.30 mg mg−1 of volatiles in all the analysed samples. The three garlic types were clearly separated by discriminant analysis of analytical traits. CONCLUSION This study investigated for the first time different Italian garlic and elephant garlic populations with respect to non‐volatile and volatile organosulphur compound content, allowing the possibility of selecting garlic accessions according to the bioactive content. © 2022 Society of Chemical Industry.

Mechanisms underlying the formation of main volatile odor sulfur compounds in foods during thermal processing

“…Garlic and onion are common food seasonings, medicinal foods, and popular commodities worldwide. The characteristic pungent odor of garlic and the tear‐inducing properties of onion primarily result from S ‐alkyl cysteine and its oxidation product, S ‐alkyl cysteine sulfoxide (like alliin) (Ferioli et al., 2022). S ‐Alkyl cysteine sulfoxide is the oxidation product of S ‐alkyl cysteine, which is synthesized inside plant bodies through cysteine by γ‐glutamyl transpeptidase, as illustrated in Figure S1 (Wermes et al., 2017).…”

Elephant Black Garlic’s Beneficial Properties for Hippocampal Neuronal Network, Chemical Characterization and Biological Evaluation

“…This species has been cultivated on Chiloe Island for centuries and has not been crossed with other species of garlic. Therefore, even though there are other studies of Allium ampeloprasum cultivated in other countries [21,22], it is important for us to evaluate the chemical composition and potential bioactive properties of this native garlic, because growing conditions and environmental factors can cause changes in its chemical composition. In addition, here, we set out a molecular, cellular and functional characterization of the potential neuroactive properties of fresh garlic (white garlic, WG) and aged garlic (black garlic, BG) of Allium ampeloprasum from Chiloe Island.…”