Zhao Liyan

Comparison of flavour qualities of mushrooms (Flammulina velutipes) packed with different packaging materials

To clarify the dynamic changes of flavour components in mushrooms packed with different packaging materials during storage, comprehensive flavour characterization, non-volatile and volatile compounds of Flammulina velutipes were evaluated using electronic nose (E-nose), electronic tongue (E-tongue) technology and headspace solid phase micro-extraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. Results showed that volatile compounds of fresh F. velutipes mainly consisted of ketones and alcohols, with 3-octanone being the predominant compound. After storage, volatile components significantly changed in mushrooms packed with normal packaging material (Normal-PM) according to the GC-MS analysis and radar fingerprint chart of electronic nose. The ethanol accumulation was inhibited by nanocomposite packaging materials (Nano-PM). Besides, both radar graph and PCA of E-tongue signals could differentiate the samples from different packaging and storage time. In general, these results may provide a profile of flavour substances and explain mechanism of flavour changes in F. velutipes over storage period.

Comparison of osmotic dehydration and ultrasound-assisted osmotic dehydration on the state of water, texture, and nutrition of Agaricus bisporus

ABSTRACT To improve product quality and osmotic efficiency, the effects of osmotic dehydration (OD) at 120 min and ultrasound-assisted osmotic dehydration (UOD) at 45 min on the nutrient composition, flavor, texture, microstructure, and water state in button mushrooms were investigated. In terms of nutrient composition, the results showed that UOD produced samples with reducing sugar, ascorbic acid, and soluble protein content at significantly higher rates than OD process. Meanwhile, UOD reduced the losses in titratable acidity, free amino acids, and 5′-nucleotides compared to the OD process, and the UOD samples also showed a better texture and microstructure. In addition, low-field nuclear magnetic resonance data revealed that the relative signal intensity of vacuole protons declined during OD process; meanwhile, the UOD was more efficient than the OD treatment. Overall, UOD process not only retained nutrient composition and flavor material more effectively but also improved the texture and efficiency of mushrooms treated with osmosis.