Study On The Characteristics Of Camellia Oil In South Belt Area

Oil-tea camellia(Camellia spp.)is the group in Camellia genus with high oil content,large economic value and widely planted in the southern of China.The core producing areas are Hunan and Jiangxi province.The south belt(SB)producing camellia oil includes most areas of Guangdong,Guangxi,Hainan and Yunnan provices.Because the cultivation areas of camellia in these provinces are almostly located south of the Tropic of Cancer,the climate and environment in this area have the unique characteristics.Are there any differences with the camellia oil between different areas?This thesis should want to answer this question.The main results are showed as follow:(1)The FA and TG composition of different samples were analyzed.The ranges of oleic acid,palmitic acid,stearic acid,linoleic acid,linolenic acid are 72.8 to 85.4%,6.1 to 11.1%,2.9 to 14.5%,1.3 to 3.8%and 0.4 to 1.0%.13 kinds of TG were measured,including LLLn,LLL,LLO,PLL,OLL+SLL,POL,PPL,OOO+SLO,OOP,POP,SOO,SLS,and SLS,range from 0?0.05%?0.03?0.40%?0.12?2.28%?0.05?0.67%?1.21?17.69%?0.27?4.38%?0.01?0.26%?58.64?82.79%?8.70?19.31%?0.06?1.28%?0.17?0.56%?1.34?6.99%?0.11?0.56%.Among them,OOO+SLO and OOP are the two most common categories,the sum of which is about 90%.The samples were compared by fingerprint,PCA and correlation analysis.It is found that the difference between fingerprints is too small to distinguish the characteristics of camellia oils.From the FA,TG conponents,the content of oleic acid,unsaturated fatty acid and ECN48 in core production area is higher than that in the southern area.And by PCA,it is found that the oil samples from the SB and the core production area can be well identified,The composition of FA and TG in the SB and the middle core area is different.(2)The ranges of AV,POV,IV,SV,refractive index and relative density are 0.38 to 2.62 mg/g;2.31 to 4.96 mmol/kg;81.76 to 89.12 g/100 g;187.97 to 196.37 mg/g;1.4611 to 1.4638;0.9211 to 0.9211 kg/m3,respectively.Comparison of refractive index and iodine value of the core area samples is slightly higher than the SB.In terms of color,the red color of the sample in the SB is slightly higher.Through PCA using the indice excepted for AV and POV,It is found that the oil characteristics of the oil samples in core areas and SB can be clearly divided.(3)The polyphenols of the samples were analyzed by HPLC and the total phenolic content of the samples was determined.The total phenol content of the oil samples(40.42 g/g)of the SB is higher than that of the core area(37.99 mu g/g).The determined polyphenols were catechin,3,4-dihydroxyphenylacetic acid and quercetin,ranges are 2.29 to 2.626 ?g/g,0.286 to 0.36 ?g/g and 0.045 to 0.43 ?g/g.Correlation analysis showed that only XL1 has significant difference in polyphenol content with other samples(P>0.01).In addition,the content of catechin in oils of the SB were slightly lower than that in core area,but the quercetin content of SB(0.169 ug/g)was about 80%higher than that of core area samples(0.094 mu g/g).(4)The oxidation stability and antioxidant capacity of the samples were measured.It was found that the average time of oxidation induction of samples was 6.04 h,while core producing area(6.64 h)>SB(5.72 h).The ORAC values of the samples range from 14.95 to 28.01 ?mol TE/100g,while core area(25.32 ?mol TE/100g)>SB(18.13?mol TE/100g).It was also found that the time of oxidation induction was significantly correlated with ORAC value(P<0.01).So the longer the time of oxidation induction,the better the oxidative stability and the higher the ORAC value.Therefore,the extracts of core area has stronger antioxidant capacity and better oxidation stability.(5)The C.osmantha and CR series are both from the Guangxi Academy of forestryis,The former is a new species,and the latter is a new breed bred from Camellia oleifera.Comparative data showed that iodine value,unsaturated fatty acid,oxidation stability and ORAC value of the oil of the C.osmantha were lower than those of other Guangxi samples.The content of iodine,oleic acid,unsaturated fatty acid and ECN48 in the oil of CR series is higher than that of C.oleifera in the SB,and it also close to the C.oleifera and XL Series in the core production area,even the oleic acid content is higher.The antioxidant and oxidative stability of the oil of C.osmantha were lower than others,while the ORAC value and the oxidation induction time of the oil of CR series were higher than that of C.oleifera in the SB,which were close to the C.oleifera in the core production area,but lower than the XL series.Therefore,the overall quality of oil of the C.osmantha is lower than that of CR series.