Research On Quality Diversity And Variation Rule Of Cross-border Sunflower Seed Oil

China is the largest consumer and importer of edible oil,of which the annual import volume of sunflower seed oil exceeds 400,000 t,higher than the yield of China.The quality and safety of imported sunflower seed oil are closely related to people’s nutrition and health.Quality evaluation and control based on simulated cooking is a hot topic in edible oil research,but non-repetitive high-temperature short-time cooking simulation which is more consistent with Chinese cooking habits is rarely reported.In addition,the time and conditions of cross-border storage and transportation of sunflower seed oil are uncertain,and there are few studies on the quality changes during the period.This project aims to construct a culinary quality evaluation plan for cross-border sunflower oil,analyze the diversity and symbolic characteristics of quality,and clarify the changes in storage and transportation quality and control schemes.The main research contents and results are as follows:(1)Study on the effect of short-time high temperature cooking on the quality of sunflower seed oil.The effects of material,temperature,time and food composition on the composition of POV,AV values and the composition of FA of sunflower seed oil were investigated.The change in POV value of sunflower oil was influenced by the interaction of the material of the appliance,cooking temperature and time.Stainless steel pot was cooked at 210 °C for 8 min,the addition of food ingredients(water,salt,sucrose,soy protein isolation)had no significant effect on POV value(P>0.05).Cooking conditions and food ingredient addition had less effect on the AV value of sunflower oil,but the AV value could be significantly increased by addition of sucrose(P<0.05).Sunflower seed oil was composed of linoleic acid(61.81%),oleic acid(31.64%),palmitic acid(2.50%)and stearic acid(1.64%),and cooking treatment under different conditions had no significant influence of FA composition.The Gas Chromatopraphy-Mass Spectrometry(GC-MS)was used to detect the effect of volatile component,sunflower seed oil extraction temperature,extraction time,extraction head type and sampling mode,and the optimization method was as follows: Headspace solid phase microextraction(HS-SPME)treatment with 75μm CAR/PDMS extraction head,extraction temperature of 60℃,extraction time of 60 min.The HS-SPME/GC-MS method was used to identify that the volatile components of sunflower seed oil mainly composed of aldehydes.(2)Evaluation and analysis of quality diversity of cross-border sunflower seed oil.Sunflower seed oils from 41 different origins with different production processes were collected and analyzed for quality diversity based on HTST cooking.The average value of POV and AV values of sunflower seed oil were 3.10mmol/kg and 0.1771mg/g,and the CV value were 36% and 146.99%,respectively.Although these values were higher after cooking,they were not exceed the limitation of national standard.The POV and AV values of domestic sunflower seed oil were generally lower than those of other sunflower seed oil producing by other countries.The POV of the products increased with the extension of shelf life,but decreased significantly after more than 24 months.The relative content CV value of C20:1,C18:3n3,C22:2 and C20:5 were higher.The content of C20:1,C18:3n3,C22:2 and C20:5 in domestic sunflower seed oil were relatively low.The FTIR models of 41 kinds of sunflower oil before and after cooking were constructed,and the similarity values were between 0.67~0.97 and 0.72~0.97,respectively.The common characteristic peaks of FTIR fingerprint were mined,and the multiple linear regression equations of FTIR fingerprint,POV value,AV value,oleic acid content and linoleic acid content were constructed respectively.The models were all extremely significant(P < 0.01),which could be used for the preliminary prediction of sunflower seed oil quality.Through multivariate statistical analysis,it was found that the volatile component GC-MS fingerprint could effectively distinguish the sunflower seed oil before and after cooking.The common characteristic peaks of fingerprints were mined respectively,corresponding to 18 and 14 substances before and after cooking,among which 11 substances were common.After statistical analysis,the Aldehydes with the largest relative content and significant cooking influence could be used as an important reference for quality evaluation.(3)The change rule of storage quality of cross-border sunflower seed oil.Modeling of cross-border shipping environment,storage temperature(room temperature and 25~70℃),length(1~11 months)of sunflower seed oil quality,illumination and so on,it was found that POV and AV values sunflower oil under the condition of different changed significantly,short-term or long-term high temperature,lighting,storage time,to influence the quality of physical and chemical quality deterioration under the room temperature away from light to save the most slowly.There was no significant difference in FA composition of sunflower seed oil during storage under different conditions.Multivariate linear regression equations of common characteristic peaks and storage quality(POV and AV values)of FTIR fingerprint were established,and the models were all extremely significant(P < 0.01),which could be used for preliminary prediction of storage quality of sunflower seed oil.Analysis of different storage conditions of sunflower oil GC-MS fingerprint of volatile components,based on the similarity analysis found that below 40℃,and the storage during the 11 months to maintain good flavor,high temperature 70℃(1 month)and light significantly influence on flavor.The common peaks of GC-MS fingerprint were dug,corresponding to 11 substances respectively.Among them,Hexanal increased significantly under different storage conditions,Octanal and Decanal first increased and then decreased,and the relative content of Heptanal also increased.In addition to the group Ⅰ(room temperature away from light)and group Ⅲ(25 ℃)under shade,during the storage(E)-2-Octene aldehyde were newly produced in other 5 groups,which can be used as a sunflower oil storage of material quality control.The relative contents of D-Limonene showed an increasing trend,however,1-Octene,Decane,Heptanoic Acid-2-Acrylic Ester and Styrax Acetate all showed a declining trend,in addition to the group Ⅰ(room temperature away from light),3-methyl-2,5-Furan Diketone in other 6 groups all decreased.In addition,2-amyl-Furan showed an increasing trend in the light group but a decreasing trend in the dark group,which could be used as a basis for the identification of storage quality of sunflower seed oil.This project established a scientific and quantitative model of cooking analyzed the diversity of cross-border sunflower seed oil and cooking quality change rule before and after cooking and analyzed the quality change rule during storage,built quality prediction model based on chemometrics method characteristic indexes and mining,for the quality of sunflower seed oil providing a scientific basis for identification and control.