Post-storage changes of volatile compounds in air- and sun-dried raisins with different packaging materials using HS-SPME with GC/MS was written by Javed, Hafiz Umer;Wang, Dong;Wu, Guang-Feng;Kaleem, Qari Muhammad;Duan, Chang-Qing;Shi, Ying. And the article was included in Food Research International in 2019.Formula: C9H10O3 This article mentions the following:
Free- and bound-form volatiles in sun-dried raisins (SDRs) and air-dried raisins (ADRs) of ‘Thompson Seedless’ were analyzed by gas chromatog.-mass spectrometry (GC/MS) for 0, 3, 6, 9 and 12 mo of storage. The compounds originating from glycosidically bound (GB) volatiles were significantly more abundant in bound-form than their free-form. A total of 89 and 88 free-form compounds were identified in ADRs and SDRs, resp. Overall, higher concentration of unsaturated fatty-acid-oxidation (UFAO) and Maillard reaction (MR) compounds were observed in the SDRs. The plastic and woven bags have an insignificant effect on the volatiles in the raisins. The main characteristics of ADR aroma were floral and fruity, while fatty, roasted, and chem. aromas were prominent in SDRs. With the exception of chem. aroma, the aromatic series (fruity, floral, herbaceous and roasted) increased during the storage duration and become more compelling in 12 mo. The packaging materials have similar effect on aromatic series, except fruity note, which was higher in woven bag. The main floral and fruity aroma contributors were decanal, β-ionone, Et hexanoate, β-damascenone, and 1-octen-3-ol. Herein we identified UFAO and MR compounds as the main contributors of raisin aromas. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Formula: C9H10O3).
Ethyl 2-hydroxybenzoate (cas: 118-61-6) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Formula: C9H10O3
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics