Study On The Effect Of Processing Methods On The Quality Formation Of Poria Cocos

Poria cocos(Poria cocos(Schw.)Wolf),mostly parasitic on the roots of horsetail pine and red pine,is a large herb used for both medicinal and food purposes,and is widely used in both the food and pharmaceutical industries.P.cocos is pre-processed by sweating(SW)or steaming(ST),and later by peeling,cutting and drying.P.cocos SW is the method described in the Pharmacopoeia of the People’s Republic of China in 2020,and ST is the currently prevalent method for processing P.cocos with differences between the origin processing and the pharmacopoeia process,and the differences between the two processes lacking scientific analysis and research.The current research on P.cocos mainly focuses on the identification of pharmacological active ingredients,pharmacological effects and mechanisms,ignoring the formation of flavour and changes in pharmacological active ingredients during processing.In this paper,the effects of different processing processes on flavour,pharmacological active ingredients and antioxidant activity were investigated,with the following main results.1.The effects of different processing processes on the changes in polysaccharide,ethanol-soluble extracts and total triterpene contents and antioxidant activity of P.cocos were investigated.The results showed that the ethanol-soluble extract and water-soluble polysaccharide contents were significantly increased(P < 0.05),the total triterpene content was no significantly changed(P > 0.05)and the antioxidant activity was significantly enhanced(P < 0.05)after the ST processing of fresh P.cocos.The ethanol-soluble extracts,water-soluble polysaccharides and antioxidant activity of P.cocos were significantly higher than those of P.cocos by steaming(P <0.05);the ethanol-soluble extracts,water-soluble polysaccharides and total triterpenes and antioxidant activity of P.cocos were no significantly changed by low-temperature drying(P > 0.05);the ethanol-soluble extracts,water-soluble polysaccharides and total triterpenes and antioxidant activity of P.cocos were no significantly changed by high-temperature drying(P > 0.05);high temperature drying did no significantly change the ethanol-soluble extract content(P > 0.05),while the water-soluble polysaccharide and total triterpene content significantly decreased(P < 0.05),antioxidant activity significantly reduced.The effect of processing process on the quality index of P.cocos were as follows: ethanol-soluble extract content varied as ST-LD and ST-HD > SW-LD and SW-HD > FR;water-soluble polysaccharide content varied as SW-LD and ST-LD > ST-HD > SW-HD and FR;total triterpene content varied as ST-LD and ST-HD > SW-HD and FR;total triterpene content varied as ST-LD and ST-HD.The variation of total triterpene content was ST-LD-,ST-HD and FR > SW-LD > SW-HD;the variation of antioxidant activity was ST-LD >SW-LD > SW-HD and ST-HD > FR.2.The effects of different processing processes on the triterpenoids of P.cocos were studied in detail by UPLC-MS/MS for the first time.33 triterpenoids were identified,the triterpenoids with high content were poricoic acid C,3-epi-Dehydrotumulosic acid,dehydroeburicoic acid and poricoic acid CM.Compared with FR,fresh P.cocos after steaming and processing 3,4-open-loop lanolin-7,9(11)-dienes and 3,4-open-loop lanolin-6,8-dienes triterpenoids content decreased;after sweating and processing lanolin-7,9(11)-dienes content increased and3,4-open-loop lanolin-6,8-dienes triterpenoids content decreased The drying process had less effect on the triterpenoids.3.HS-SPME-GC-MS was used to study the effect of different processing processes on the volatile components of P.cocos and the change pattern,a total of 66 volatile components were identified.Compared with freeze-dried fresh P.cocos,the results showed that the total ester,total aldehyde and total aromatic volatile components were significantly increased after SW processing of fresh P.cocos(P <0.05);after ST processing,the total aldehyde and total aromatic volatile components were significantly increased,and the total ester and total alcohol volatile components were significantly decreased(P < 0.05).Steaming P.cocos and sweating P.cocos drying process,ester and aldehyde volatile components tend to increase,alcohol volatile components tend to decrease.4.The effect of different processing processes on the aroma of P.cocos was studied in detail using OAV combined with aroma descriptions,and a total of 18 aroma substances contributing to the aroma of P.cocos were identified.The top three aroma substances contributing to the aroma of P.cocos were 1-octen-3-ol with mushroom aroma,trans-2-nonenal and hexanal with lipid aroma.After fresh P.cocos was dried by ST or SW,the content of 1-octen-3-ol decreased significantly(P < 0.05)and the mushroom aroma was reduced,while the content of trans-2-nonenal and hexanal increased significantly(P < 0.05)and the lipid aroma became stronger,resulting in a special mushroom aroma.5.The correlation between the triterpenoids and volatile components of P.cocos and their antioxidant activity was investigated in detail using PLS analysis.Triterpenoids such as tumulosic acid,3β-p-hydroxybenzoyldehydrotumulosic acid,poricoic acid AM,3-epi-dehydrotumeric acid and poricoic acid E and volatile components such as campholenic aldehyde,terpinene-4-ol,heptanal,trans-2-octenal and benzaldehyde were highly positively correlated with the antioxidant activity of P.cocos,and we suggest that these substances are important contributors to the antioxidant activity of Poria.