Characterization of Volatile Component Changes in Jujube Fruits during Cold Storage by Using Headspace-Gas Chromatography-Ion Mobility Spectrometry

Abstract

Volatile components in jujube fruits from Zizyphus jujuba Mill. cv. Dongzao (DZ) and Zizyphus jujuba Mill. cv. Jinsixiaozao (JS) were analyzed under different cold storage periods via headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). Results identified 53 peaks that corresponded to 47 compounds and were mostly alcohols, aldehydes, esters, and ketones. Differences in the volatile components of jujube fruits were revealed in topographic plots and fingerprints. For DZ, 3-pentanone was the characteristic component of fresh fruits. After storage for 15 days, dipropyl disulfide became the most special substance. Moreover, when stored for 30 and 45 days, the fruits had some same volatile components, like 2-pentyl furan and diallyl sulfide. However, for DZ stored for 60 days, esters were the prominent constituent of the volatile components, simultaneously, some new alcohols appeared. For JS, 2-ethyl furan was the representative of fresh fruits, and 2-butoxyethanol content was the most abundant after 15 and 30 days of storage. Different from that in DZ, the content of ester in JS increased after storage for 45 days. Substances such as amyl acetate dimer, methyl salicylate, and linalool greatly contributed to the jujube flavor during the late storage period. Principal component analysis (PCA) showed that fresh samples and refrigerated fruits were effectively distinguished. Heat map clustering analysis displayed the similarity of volatile components in different samples and was in accordance with PCA results. Hence, the volatile components of jujube fruits can be readily identified via HS-GC-IMS, and jujube fruits can be classified at different periods based on the difference of volatile components.

Characterization of Volatile Organic Compounds of Healthy and Huanglongbing-Infected Navel Orange and Pomelo Leaves by HS-GC-IMS

“…VOCs with the same name in the fingerprints are presented as monomers, dimers, or polymers. The drift time of dimers or polymers was increased due to their proton affinity and higher content [ 27 ]. The composition and contents of VOCs in HEAO and HLBO can be compared intuitively using fingerprints.…”

“…The qualitative analysis of VOCs in HEAO and HLBO is represented in Table 1 and Figure 6 . Some VOCs presented multiple signals as monomers, dimers, and polymers, due to their varying concentrations and adducts formation while moving through the IMS drift tube [ 27 ]. These VOCs had the same GC retention times, but different drift times.…”

“…The analysis method was performed as described by Yang et al [ 27 ]. Fresh leaf (1 g, without any pretreatment) was cut into small pieces and transferred to a 20 mL headspace vial and then incubated at 40 °C for 20 min.…”

“…The IMS technique has been employed widely and successfully to detect chemicals in agricultural analysis, foods, and pharmaceutics [ 26 ]. It has been proved to be a very effective technique for the identification and quantification of VOCs with different properties in the gas phase [ 27 ]. Combining IMS with GC is a more efficient method to make better use of its advantages, especially improving the analytical selectivity of complex samples [ 28 ].…”

Influence of Electrostatic Field on the Quality Attributes and Volatile Flavor Compounds of Dry-Cured Beef during Chill Storage

“…Dry-cured beef samples (n = 18) for volatile compounds analysis were collected in duplicate at 0, 3, 7, 10, and 14 days. Volatile compounds of dry-cured samples were performed using the Gas Chromatograph -Ion Mobility Spectrometer (GC-IMS) equipment (FlavourSpec®, Dortmund, Germany) in accordance with the method of Yang et al [22] with some modifications. We weighed 2.0 g of each sample, and each sample was transferred to a 20 mL headspace vial and then incubated at 60 • C for 15 min.…”