The Influence Of Drying Methods On Flavor Components Of White Hypsizygus Marmoreus

As an edible officinal fungi, white Hypsizygus marmoreus, which was rich in functional biological active substances and has a seafood-like flavor, was getting more and more attention and favor because of its delicious taste. But the research of deep processing laged behind, so there is little development and production of related products. The basic nutrients and flavor components of white Hypsizygus marmoreus was comprehensively studied, then using e-nose and SPME/GC-MS to study the influence of four drying methods (hot drying, vacuum drying, microwave vacuum drying and vacuum freeze drying) on the volatile flavor components, and using HPLC to measure and analyze the influence of four drying processes on the non-volatile flavor components. The results as follow:1、The water content (in fresh sample), crude ash, crude protein, crude fat, crude fiber and carbohydrate content of white Hypsizygus marmoreus were 92.04%、7.73%、26.83%、 2.91%、12.76%、49.78%, by GB mothod respectively. White Hypsizygus marmoreus contained Ka、Mg、Na、Ca、Fe、Mn、Cu、Se、Zn, Ka、Mg、Fe and Zn were higher in content. White Hypsizygus marmoreus had 17 kinds of free amino acids, essential amino acids was 24.72%, which was higher than egg model and WHO/FAO value. MSG-like amino acids was 30.61%, Asp and Glu were higher in content.2、Principal component analysis (PCA) and discrimination function analysis (LDA) showed that e-nose could distinguish fresh white Hypsizygus marmoreus and four drying products(HD, VD, MVD, FD) clearly. By using GC-MS, the results showed that:fresh sample mainly contained the alcohols、aldehydes and ketones,1-octene-3-alcohol, trans-2-nonene aldehyde and 3-ketone were higher in content. Different drying methods had great influence on the volatile flavor components. HD samples mainly contain alcohols and esters, benzene ethanol and 2-phenylethylester were higher in contain. VD samples mainly contained alcohols, ketones,2-3-octene-ketone and 2-methyl-3-symplectic ketone were higher in contain. MVD samples mainly containded pyrazines,3-ethyl-2,5-dimethyl pyrazine and 2,5-dimethyl pyrazine were higher in content.VD samples mainly contained hydrocarbon compounds,2,6-dimethyl undecane and 2-methyl undecane were higher in content.Four drying methods would be damage to the eight carbon compounds, especially to eight carbon alcohol greatly, extent of damage were MVD>FD>VD>HD. HD produced more ester materials, MVD produced more aldehyde materials, VD produced more ketone substances. At the same time, just VD did not detect the acids composition of four drying methods.3、By using HPLC, the results showed:trehalose、mannitol、succinic acid and 5’-IMP were higer in content, which were the mian non-volatile flavor substances white Hypsizygus marmoreus. Four drying methods had a significant impact on the non-volatile flavor substances of white Hypsizygus marmoreus. Trehalose was still the main soluble sugar in four drying samples, and succinic acid were also still the highest in content. There was no significant difference between four drying products and fresh sample, while the MSG-like、essential and non-essential amino acids were all significantly higher than fresh sample. Soluble sugar (alcohol) can be well retained by MVD, free amino acid can be well retained by VD, organic acid can be well retained by FD, flavor nucleotides can be well retained by HD.Equivalent Umami Concentration (EUC) of fresh white Hypsizygus marmoreus and four drying samples are all in the second level. There was no significant difference between FD and fresh sample, while the EUC of VD、FD and HD were significantly lower than fresh sample.