Changes of Volatile Flavor Compounds in Sea Buckthorn Juice during Fermentation Based on Gas Chromatography–Ion Mobility Spectrometry

Abstract

Sea buckthorn is rich in polyphenolic compounds with antioxidant activities. However, it is very sour, and its odor is slightly unpleasant, so it requires flavor improvement. Fermentation is one potential method. Sea buckthorn juice was fermented at 37 °C for 72 h and then post-fermented at 4 °C for 10 days. The flavor-related properties of the sea buckthorn juice were evaluated during fermentation, including the pH, total soluble solids (TSS), color, sensory evaluation, and volatile flavors. The sea buckthorn fermented juice had a low pH. The total soluble solids decreased from 10.60 ± 0.10% to 5.60 ± 0.12%. The total color change was not more than 20%. Fermentation increased the sweet odor of the sea buckthorn juice, but the fruity flavor decreased and the bitter flavor increased. A total of 33 volatile flavors were identified by headspace gas chromatography–ion mobility spectrometry (GC–IMS), including 24 esters, 4 alcohols, 4 terpenes, and 1 ketone. Their total relative contents were 79.63–81.67%, 10.04–11.76%, 1.56–1.22%, and 0.25–0.55%, respectively. The differences in the characteristic volatile molecular species of the sea buckthorn juice at different fermentation stages could be visually discerned using fingerprint maps. Through principal component analysis (PCA), the total flavor difference of the sea buckthorn juice at different fermentation stages could be effectively distinguished into three groups: the samples fermented for 0 h and 12 h were in one group, the samples fermented for 36 h, 48 h, 60 h, and 72 h were in another group, and the samples fermented for 24 h were in another group. It is suggested that sea buckthorn juice be fermented for 36 h to improve its flavor. GC–IMS and PCA are effective methods of identifying and distinguishing the flavor characteristics of sea buckthorn juice. The above results can provide a theoretical basis for studying the changes in sea buckthorn’s characteristics as a result of fermentation, particularly with regard to its flavor.

The potential correlation between the succession of microflora and volatile flavor compounds during the production of Zhenba bacon

“…The results showed that the type and content of VOCs increased with increasing of fermentation time. This finding is similar to that previously reported that fermentation can increase VOCs ( Wu et al, 2022 ).…”

The consequences of fermentation metabolism on the qualitative qualities and biological activity of fermented fruit and vegetable juices

“…Esters play an important role in improving the flavor of fruit and vegetable juices, and are generally formed from the esterification of acids and alcohols produced after fermentation. The fermentation of lycium berry juice by Lactobacillus Swiss resulted in the accumulation of fruity esters, especially the highest content of ethyl acetate, which was the result of the synthesis of acetyl-CoA and acetyltransferase ( Wu et al, 2022 ) in the fermented sea buckthorn juice with four species of lactic acid bacteria, and the results showed that after fermentation by lactic acid bacteria, the acidity of sea buckthorn juice was significantly improved, while bitterness and astringency were significantly reduced. After fermentation by Lactobacillus plantarum , the volatile content in Seabuck Buckans juice was the highest, especially a large number of esters, such as ethyl caproate, isoamyl isovalerate, ethyl capryl, ethyl benzoate, ethyl butyrate, etc., and the sensory evaluation of Lactobacillus plantarum group was also the highest.…”

A Comparison of Volatile Organic Compounds in Puerariae Lobatae Radix and Puerariae Thomsonii Radix Using Gas Chromatography–Ion Migration Spectrometry

“…In the process of substance analysis, the sample requires limited pretreatment to retain the sample's smell to the maximum extent, and via signal integration in the spectrum, the visualization of flavor substances can be realized, and the types of VOCs in the sample can be rapidly analyzed [20][21][22][23]. It has been widely used in the analysis of food flavor [24][25][26][27][28][29]. He Jia used HS-GC-IMS technology to analyze VOCs in Ophiopogon from different producing areas, and these characteristics could effectively identify Ophiopogon from Sichuan and Zhejiang, as well as the two traditional main producing areas of Cixi City and Sanmen County, providing a scientific basis for the identification of Ophiopogon origin [30].…”