Study Of Inhibitory Effect Of Flavonoids On Harmful Products From Maillard Reaction In Cakes

Chiffon Cake is one of the common cakes,the main components of it are wheat flour,egg white,sugar,vegetable oil.A series of chemical reactions can occur among the oil,protein and sugar in the cake under high temperature,including Lipid oxidation,Maillard reaction and caramelization,which can produce high activity 1,2-dicarbonyl compounds,such as glyoxal(GO)/methylglyoxal(MGO)and advanced glycation end products(AGEs).When these substance were ingested,they will be accumulated in the body and cause Diabetes complications,cardiovascular and cerebrovascular diseases and other chronic diseases,which can do harm to human health.Oil system,ovalbumin(OVA)-sugar system,chiffon cake system are established in this paper,To study the influence factors of MGO/GO and AGEs in the process of cake processing and adding inhibitor(mainly five kinds of flavonoids:quercetin,rutin,genistein,catechin,luteolin).The formation of GO/MGO and AGEs in the system is effectively controlled,so as to improve the safety of baking food.1.Oil system:indicating the stability at different tempeture of several commonlyused oil(corn oil,soybean oil,palm oil,margarine)through Rancimat,studying the changes of induction time of oil,peroxide value(POV),content of GO and MGO,and study the effect of flavonoids(quercetin,rutin,genistein,catechin,luteolin)and antioxidant TBHQ on lipid oxidation and the formation of GO/MGO process.The results showed that:(1)As the temperature rises,the induction time decreased in same oil;The order of induction time of different kinds of oil in the same temperature is soybean oil,corn oil,margine,palm oil.With the extension of time,the POV of oil is increased to a maximum value and then maintain at the maximum value or gradually reduce.(2)At the same temperature,Corn oil reach to the extreme point of POV is the fastest,which show corn oil is the most easy to oxidation;The POV value of the same kind of oil at different temperature was higher than that of the induction time,and the induction time was gradually close with the increase of the temperature.(3)Oil heating in high temperature(130-210?)will produce GO and MGO,which go is much higher than that of MGO.(4)Flavonoids can slow down the process of lipid oxidation,such that the induction time delay 2-3 times;when the addition amount is 1.00 mmol/L and react 1 h,the inhibition rate of GO/MGO respectively reach 64.80%and 21.96%,TBHQ compared to the selected flavonoids in this experiment has strongest antioxidant effect on lipid oxidation,but the inhibition effect on GO/MGO is weaker.2.OVA-sugar system:Simulating baking cake system,investigate the influence factors of generating GO/MGO and AGEs:the substrate,substrate concentration,temperature,pH value and flavonoids.Above factors have effect on the formation of GO/MGO and AGEs.(1)The total amount of GO and MGO which produced from OVA glycosylation by different sugar from high to low in order is xylose,arabinose,fructose,glucose,maltose,lactose,sucrose,xylitol,and AGEs formation is generally consistent.(2)With the increase of substrate concentration,temperature and reaction time,the amount of GO/MGO and AGEs increased gradually to a certain amount.(3)At high temperature(? 150?)conditions,after the reaction to a certain time,the content of GO and AGEs show a downward trend.It is obvious to see the decrease time of the content of GO and MGO will be more obvious with the increase of temperature and substrate concentration.(4)The stronger the alkalinity,the shorter the time to reach the equilibrium phase of GO/MGO and AGEs.(5)With the adding concentration of natural flavonoids increased,inhibitory effect continuously enhance,the inhibition effect on the fluorescence of advanced glycation end products is consistent with GO+MGO,from high to low as follows:Quercetin,rutin,luteolin,dye lignin,catechin.When the content of quercetin was 1.00 mmol/L,the inhibition rate of AGEs and GO+MGO were 80.02%and 50.59%respectively.3.The content of GO in cakes on sale range from 12.2 to 36.O?g/g DW,the average value is 21.3 ?g/g DW;the content of MGO range from 16.6 to 97.8p.g/g DW,the average value is 44.3?g/g DW.In order to analyse the changes of GO,MGO and AGEs contents in the cake,chooseing Chiffon Cake as research object and select different processing techniques(steaming,baking,temperature,time)and formula(sugar type,oil type,acidity regulator,egg yolk ratio).Flavonoids(quercetin,rutin,genistein,luteolin,catechin)can inhibit the content of GO/MGO/AGEs in cakes.(1)Temperature:The content of GO/MGO/AGEs in the system with the increase of temperature(150-190?)and time(20-35 min)was positively related to the upward trend,the content of MGO was higher than GO with the increase of temperature.At the same temperature,the content of MGO were higher than those of GO.(2)The effect of the type of sugar on the GO/MGO and AGEs in the cake was consistent with that of the OVA-sugar system.(3)The effects of oil on GO/MGO and AGEs formation were from high to low as follows:corn oil,soybean oil,palm oil,margine,which is consistent with the amount of GO/MGO generated in the oil system.(4)The content of GO/MGO and AGEs showed a decreasing trend with the increase of acidity regulator and the decrease of pH(8.5-5.4)value of the cake system.(5)Adding egg yolk below 40%,with the egg yolk to reduce the amount of harmful indicators can significantly reduce.(6)Due to the high tempeture,the cake which baked produced more GO/MGO and AGEs then the cake steamed.(7)The total inhibitory effect of GO+MGO and AGEs are consist with OVA-glucose system among quercetin,rutin,genistein,luteolin,catechin.The best adding amount of cake system was 0.3%.Under the premise of considering the taste of the cake,preferred choose rutin,genistein,catechin,luteolin.The stability of flavonoids decreased under high temperature condition,The residual rate is genistein(97.79%),rutin(90.73%),Catechin+catechin isomers(42.84%+21.59%)(part of catechin transform into isomers by heating);LC-MS analysis on the structural changes of rutin and catechin in cake,these two kinds of flavonoids were found to capture MGO and form adducts(rutin-MGO and catechin-MGO).