The Research On The Aroma Components Of Baked Torreya Nuts

Torreya is a rare fruit in China.It is a food with high nutritional value which has rich oil,protein,vitamins and minerals.It has a special aroma and is richer after baking,so it has good edible value and can be eaten as a snack food.However,there have been few reports on the aroma components produced after the baking of the Torreya nuts.In this study,the aroma components of the Torreya nuts were used as the research object,and we adopted solid phase microextraction-gas chromatography-mass spectrometry(SPME-GCMS)to compare the differences of volatile substances in the Torreya nuts;Based on the above research results,the aroma components with unique aromatic flavors were selected as experimental materials to study the characteristics and changes under different baking conditions,and cluster analysis was used to analyze the aroma components under different baking conditions.Determine preferred baking conditions;At the same time,in order to more fully grasp the characteristics of the aroma components of roasted Torreya nuts,we used comprehensive two-dimensional gas chromatography-mass spectrometry(GC×GC-TOFMS)to systematically analyze and identify the aroma components.The above research results could provide a theoretical basis for the efficient use of Torreya nuts and the development of deep processing products.The main research contents and results were as follows:1.Differences in volatile components among the varieties of Torreya nuts:A total of 122 compounds were obtained through detecting and analyzing volatile constituents of three varieties of torreya(sesame,scorpion,millet)before and after roasting by SPME-GCMS.The volatile components of the three kinds of Torreya nuts were mainly composed of alkenes,esters and alcohols.After baking,they had a unique flavor due to the formation of organic compounds such as pyrazine furan,aldehyde ketone and pyridinium pyrrole.The aroma profile analysis showed that the sesame kernels were nutty,cocoa and cooked sugary,and the caramel scent was prominent;the fruit of small round nuts was bananas and pineapples;the scent of the millet nuts was prominent,and the light pine needles were obvious.2.Characteristics and variation of aroma components of Torreya nuts under different baking conditions:(1)A total of 90 aroma components with certain aroma characteristics were identified at different baking temperatures(130,150,170,200,230?),including esters,pyrazine and furans,aldehydes and ketones,alkenes,pyrrole and pyridine,alcohols,phenols and so on.With the increased of baking temperature,the types and contents of aroma compounds increased gradually until a relatively stable trend,among them,millet nuts had the highest aroma content when baked at 170?,which was 44.38 mg/kg,1 70? was its best baking temperature.Cluster analysis of aroma components produced under different baking temperature conditions,divided into three types of characteristic substances,130? and 150? for olefinic,170? for pyrazine furans,aldehydes and ketones,200?and 230? for pyrazine furan,phenolic.The results showed that different baking temperatures corresponded to the aroma components of different characteristics of the Torreya nuts.(2)Aroma components of 73 kinds were identified under different baking time(20--60min),with the increased of baking time,the content of aroma compounds increased first and then decrease,at 40min,the content of aroma substances was the highest,it was 40mg/lkg,and 40min is the best baking time.The aroma components produced under different baking time were clustered and divided into two types.20min and 30min were olefinic aroma substances,and 40min,50min and 60min werre pyrazine furans and aldehydes and ketones.The results of the study showed that different baking times corresponded to the aroma components of different characteristics of the Torreya nuts.(3)A total of 72 compounds were identified in the baked aroma components of different degrees of brokenness(whole fruit,half kernel,four kernels,crushed kernels,broken kernels),with the increased of the brokenness,the content of the aroma compounds increased firstly to a gradual stable trend.among them,the content of aroma components reached saturation in the form of broken kernels,which was 38.56 mg/kg,and the shape of broken kernels was the best baking degree.Cluster analysis was divided into two types,one was the pyrazine furan and the alkene aroma of whole fruit,half kernel and four kernels,the other type was pyrazine furans and aldehydes and ketones of crushed kernels and broken kernels.The results showed that different degrees of fragmentation corresponded to the aroma components of different characteristics.3.Comprehensive systematic analysis of the aroma components of Torreya nuts:The flavor components of millet kernels under optimal baking conditions were analyzed by GC×GC-TOFMS.The 215 aroma substances were identified,the main components were aldehydes and ketones and pyrazine furan compounds,and pyrimidines and alkynes were detected.