Metabolomics Reveals Heterogeneity in the Chemical Composition of Green and White Spears of Asparagus (A. officinalis)

Abstract

Green and white asparagus are quite different crops but can be harvested from the same plant. They have distinct morphological differences due to their mode of cultivation and they are characterised by having contrasting appearance and flavour. Significant chemical differences are therefore expected. Spears from three varieties of both green and white forms, harvested in two consecutive seasons were analysed using headspace GC-MS and LC-MS with an untargeted metabolomic workflow. Mainly C5 and C8 alcohols and aldehydes, and phenolic compounds were more abundant in green spears, whereas benzenoids, monoterpenes, unsaturated aldehydes and steroidal saponins were more abundant in white ones. Previously reported key asparagus volatiles and non-volatiles were detected at similar or not significantly different levels in the two asparagus types. Spatial metabolomics revealed also that many volatiles with known positive aroma attributes were significantly more abundant in the upper parts of the spears and showed a decreasing trend towards the base. These findings provide valuable insights into the metabolome of raw asparagus, the contrasts between green and white spears as well as the different chemical distributions along the stem.

Analysis of volatile organic compounds and metabolites of three cultivars of asparagus (Asparagus officinalis L.) using E-nose, GC-IMS, and LC-MS/MS

“…These aldehydes have been identified in asparagus. Among these, benzeneacetaldehyde, octanal, and 3-methylbutanal are regarded as vegetable VOCs, and their aroma are associated with floral, fruity, and fresh [ 8 , 34 ]. These two acids were first reported in asparagus.…”

“…In recent years, studies have reported on the metabolic profiles of asparagus, revealing differences in metabolomics between green and white spears of asparagus. Green spears mainly contained aldehydes and phenols, whereas white spears mainly contained benzenes, steroidal saponins, and unsaturated aldehydes [ 8 ]. The main differences in taste are that green asparagus is grassy and bitter, whereas white asparagus is similar to sweet corn, potatoes, and butter [ 9 , 10 ].…”

“…Volatile organic compounds (VOCs) constitute the aroma characteristics, which are key determinants of flavor in asparagus [ 12 ]. Several specific VOCs, such as methional, 2-methoxy-3-isopropyl pyrazine, and dimethyl sulfide, are considered key odorants and are used as industrial references for the odor quality of asparagus [ 8 ]. However, phytochemical characteristics, especially the differences in VOCs and metabolic profiles between purple and green asparagus, have rarely been investigated.…”

A physiological and metabolomic analysis reveals the effect of shading intensity on blueberry fruit quality

“…Different environments lead to the development of different plant traits, which can also be transformed into variations in metabolomes ( Pegiou et al, 2021 ). For example, Lee et al (2013) analyzed the effect of shade treatment on the nutritional and sensory qualities of green tea using metabolomics technology.…”

Spray drying of asparagus waste into flavour-rich ingredients

“…The semipolar compounds were extracted by mixing 0.3mL of each soup replicate with 0.9mL 32.04M methanol and 0.035M formic acid followed by sonication and centrifugation, as described previously by De Vos et al ( 2007). The LC-MS calibration and analysis settings were as previously described (Pegiou et al, 2021) using both negative and positive ionization modes of the Q Exactive™ Plus Hybrid Quadrupole-Orbitrap™ Mass Spectrometer (Thermos Fisher Scientific™, Germany). A 0.3mL from the same mixture of all samples as prepared and mentioned in 6.2.6, was used for each QC sample and analysed in the same way as the biological samples.…”