Identification of the cooked off-flavor in heat-sterilized lychee (Litchi chinensis Sonn.) juice by means of molecular sensory science. (15th December 2019)

• Record Type: Journal Article
• Authors: An, Kejing; Liu, Haocheng; Fu, Manqin; Qian, Michael C.; Yu, Yuanshan; Wu, Jijun; Xiao, Gengsheng; Xu, Yujuan
• Is Part Of: Food chemistry. Volume 301(2019)
• Publication Date: 2019-12-15
• Subjects: FLJ Fresh lychee juice -- HLJ Heat-sterilized lychee juice -- GC–MS gas chromatograph-mass spectrometry -- HS-SPME headspace-solid-phase microextraction -- GC-O gas chromatography-olfactometry -- AEDA aroma extract dilution analysis -- FD flavor dilution -- OAV odor activity value -- SPME solid phase microextraction -- CAR-PDMS carboxyl-poly dimethyl siloxane -- VSCs volatile sulfide compounds -- DMS dimethyl sulfide -- DMDS dimethyl disulfide -- DMTS dimethyl trisulfide; Dimethyl sulfide (PubChem CID: 1068) -- Methional (PubChem CID: 18635) -- Dimethyl disulfide (PubChem CID: 12232) -- Dimethyl trisulfide (PubChem CID: 19310) -- 3-Methylbutanal (PubChem CID: 11552) -- 2, 4-Dithiapentane (PubChem CID: 15380) -- cis-Rose oxide (PubChem CID: 1361574) -- 2-Methyl-3-buten-2-ol (PubChem CID: 8258) -- β-Damascenone (PubChem CID: 5366074) -- (E)-2-Hexenal (PubChem CID: 5281168); Lychee juice -- Off-flavor -- Aroma extract dilution analysis -- Odor activity value -- Aroma recombination; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.125282
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Molecular sensory science was applied to clarify the key cooked off-flavor odorants. Five sulfides and 3-methylbutanal were identified as the main off-flavor contributors. The main cooked off-flavor odorants were further verified in other lychee varieties. Identification of the off-flavor odorants in lychee juice is the key to control of it. Abstract: The main contributors to the cooked off-flavor in heat-sterilized lychee juice (HLJ) were studied by means of molecular sensory science. The HLJ which elicited cooked cabbage/potato and onion/garlic off-flavor was compared with fresh lychee juice (FLJ) having desired sensory attributes via chemical analysis and sensory evaluation. Aroma extract dilution analysis, quantitative analysis and calculation of odor activity values (OAVs) were conducted on both FLJ and HLJ. The results showed that compared with FLJ, 15 compounds had increased OAVs in HLJ, among which, dimethyl sulfide (DMS), methional, dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and 2, 4-dithiapentane presented cooked cabbage/potato, garlic/onion and sulfurous impression. The omission experiment proved that DMS, methional, DMTS, DMDS, 3-methylbutanal and 2, 4-dithiapentane had significantly negative effects on the overall aroma of HLJ. Further studies on HLJs from other varieties of lychee confirmed that DMS, methional, DMTS, DMDS and 3-methylbutanal were responsible for the cooked off-flavor of HLJ in general.