A Study On The Quality Appraise And Fast Determination Of The Polar Compounds Of Deep Frying Oil

Frying is a common and popular process often utilized in the food industry due to its significant sales and vast quantity of products.From the consumers' standpoint fried food palatability is related to unique organoleptic and sensory characteristics,including flavour,texture and appearance.Fried foods play a significant role in the enormous growth of fast foods.But,there were complicated chemical reactions and oil deterioration during deep frying.The harmful components in deteriorated oil would make harm to pepole with the uptake of fried foods.It was important to take a further study on the effect factors to oil deterioration during deep frying,and quality changes and harm appraise of frying oil.On the bases of research papers investigation,the advance in frying process,chemical change,the quality change of edible oil during deep frying,and the quality analysis to deep frying oil and its harm to animal and human were reviewed.Then,four kinds of frying oil were processed by four common edible oil such as rapeseed oil,soybean oil,peanut oil and palm oil,and their quality analysis,harm appraise,affect factors and fast determination of the polar compounds were investigated with instrumental analysis technique,medical analysis technique, animal toxicology appraise method in this paper.The results indicated:(1) The content of polar compounds in frying oil was increased by prolonging the frying time and enhancing the frying temperature.In food processing,it is suggested that the frying temperature was 180℃,and the frying time was under 8h. Different kinds of edible oil had different frying capability.The palm oil was fit for deep frying,and its frying capability was better than the other three oils.For the different kinds of food material such as paste strip,potato strip,lotus root slice,banana and tofu processing in deep frying,they had different contribution to the content of total compounds in frying oil.The content of total compounds in frying oil increase most after the oil had fried tofu.(2) The quality of frying oil was analysed by peroxide value,polar compounds, acid value,absorbance,color,refractive index,viscosity and synchronous fluorescence spectrum.When edible oil was fried in the same condition,the color became dark,and the flavor dribbled away,and the lampblack became thick,and the changes of peroxide value,acid value and the content of polar compounds had no regularity,whereas the absorbency,total chromatism,refraction index and viscosity all increased with the increasing of frying time.When edible oil was fried in the same condition,the changes of peroxide value were decreased,and the changes of acid value and the content of polar compounds had no regularity,whereas the absorbency,total chromatism, refraction index and viscosity all increased with the increasing of frying time.The quality of deep frying oil was relation to the variety of edible oil and food material. There had similar with the synchronous fluorescence spectrum of rapeseed oil,soybean oil,peanut oil and palm oil.Compared with the fresh oil,the fluorescence intensity of the four kinds of oils had a trend of decrease after had been fried.When the oils fried for different time,the most fluorescence intensity appeared at the different wavelength,and the values of fluorescence intensity were different and their changes had no regularity.(3) The content of the polar compounds of fried soybean oil,rapeseed oil, peanut oil and palm oil had good relativity with their conductivity,and the linear regression equation of the four kinds of oil were y＝35.468x-18.027,y＝21.618x-23.110, y＝73.883x-63.344,y＝58.478x-78.067,and the four correlation coefficient were 0.9737, 0.9835,0.9611,0.9645.For 5 random frying oil samples,their repeatability of determination of their conductivity were preferable,and the relative standard deviation were in the range of 2.78%～4.27%,all less than 5%.There were good relativity between the content of the polar compounds of frying oils that determined by column chromatography and by conductivity,and the linear regression equation was y＝1.0319x-0.4901,and the correlation coefficient was 0.9262.It is indicated that the accuracy of the content of the polar compounds of frying oils determined by conductivity was preferable,and the conductivity method can be used in the fast determination of the content of the polar compounds of frying oils.(4) Feeding frying oil in the acute toxicity experimentation could bring badness reaction to mice.The hair of mice was incompact,unclean,lackluster.Few mice rufused food,and their stool became watery.These deviant phenomena would be changed gradually after two weeks.At the end of the acute toxicity experimentation,no mouse had dead,and the weight of mice feeding frying oil had no significant difference with the mice with normal diet(P＞0.05).The result showed that LD₅₀ of frying oil to mice after oral administration was higher than 55200mg/kg,and the frying oil could be considered as practical innoxious substance.(5)Biological characteristic determination of mutant strains TA97,TA98,TA100 and TA102 of salmonella typhimurium suggested that four mutant strains coincide the requirement of microsomal enzyme test(Ames test).Masculine mutagen could lead mutation effectually.The number of colony of mutant strains of 5 dose groups of frying oil had not exceed that of the normal group by two times.The experiment indicated that frying oil could not increase the number of colony of mutant strains of TA97,TA98, TA100 and TA102 of salmonella typhimurium whether action directly(not add S-9 admixture) or action after metabolism activation(add S-9 admixture).And there were no relationship between the dose and the reaction.The frying oil used in experiment do not have any mutagenicity on mutant strains TA97,TA98,TA100 and TA102 of salmonella typhimurium in vitro with 5 dose group.(6) In the experiment of micronuclear of marrow cells in mice,it appeared that different degree of micronuclear of marrow cells in all of the groups of frying oil and masculine group,and their micronuclear ratio were higher than that of the normal group. And there were no relationship between the dose and the reaction.The experiment indicated that frying oil had no darmnification effect to micronuclear of marrow cells in female mice,and had darmnification effect to the marrow cells chromosome of male mice,and had mutagenicity to male mice.(7) In the experiment of malformation of spermatozoa in male mice,it appeared that feeding frying oil to male mice could have damage to their spermatozoa,and different degree of malformation to their spermatozoa.For the different of dose and mice individual,the type of malformation of spermatozoa in male mice were different, including no-hook in tail,looking as banana and tail folding mostly.And there were no obvious relationship between the dose and the reaction.Frying oil could increase the ratio of malformation of spermatozoa in male mice.The experiment indicated that frying oil had darmnification effect to malformation of spermatozoa in male mice,and had mutagenicity to male mice.(8) In the 30 days feeding experiment,all of the rats feeding with frying oil had symptom such as stool became watery,walking unsteadily,and having no desire to move.These deviant phenomena would be changed to normal gradually after two or three days for the lower and middle dose group.However,for the highest dose group, the rats needed more time to change to normal.The deviant reaction was more serious for the rats which had lower weight.In the course of experiment,some rats eated less food after feeding frying oil,and the weight loss.There were rats dead in the three groups that feeding frying oil.Compared with the normal group,total food utilizing ratio of rats feeding frying oil was lower,and the last weight of rats in the three groups that feeding frying oil was lower,and there were significant difference.Especially,the weight of very few rats was less than the original weight.The blood routine and haemal biochemical experiment indicated that the results increase or decrease abnormally for hemoglobin(HGB),platelet(PLT),neutrophil,lymphocytes,alanine aminotransferase (ALT),triglyceride(TG) and total cholesterol(TC).These abnormity might have relationship to liver damage,immune barrier,inflammation and splenic dysfunction of rats after taking frying oil.In some groups,organ/body ratio of liver an ovary in rats were higher abnormally,whereas the ratio of heart,spleen and kidney in rats were lower abnormally.These abnormity might have relationship to organ hyperaemia,dropsy, atrophy,hyperplasia and hypertrophy,degenerative changes of rats after taking frying oil.The results of gross anatomy indicated that the appearance,color and size of heart, liver,spleen,kidney,stomach,intestines,pulmonary,ovary and testis were in the range of normal morphology basically,and there were no obviouse pathological changes such as hyperplasia,dropsy,atrophy and so on.The result of pathology slices indicated that there were different degree of pathological changes in heart,liver, pulmonary,kidney,stomach,intestines,ovary and testis.Especially,the primary organ that might occur pathological changes were heart,liver,kidney,stomach,intestines, ovary and testis.The innovations of this paper are:the quality and harm analysis of frying oil,the influencing factors and fast determination of the content of polar compounds were firstly systematically studied.The quality of frying oil as sense characteristic,total chromatism,refraction index,viscosity,acidvalue,peroxide value,the coment of polar compounds and fluorescence intensity were studied with traditional analysis methods and nowadays instrument methods The acute toxicity,mutagenicity(including Ames test,micronuclear of marrow cells and malformation of spermatozoa),30 days test of frying oil were studied with animal toxicology appraise method.The conductivity method was firstly and successfully studied in the fast determination of frying oil.