The Study On The Change Of Acrylamide In Coffee Roasting Process And The Inhibition Of Antioxidants On Acrylamide

Coffee is one of the most popular beverages in the world because of its unique aroma and taste.However,coffee would produce potential harmful substances,such as acrylamide(AAM)in the process of high-temperature roasting.AAM has neurotoxicity,reproductive toxicity and potential carcinogenicity.The international agency for research on cancer listed AAM as "a possible carcinogen for human beings".The consumption of coffee is closely related to the dietary exposure to AAM.Therefore,it is of great significance to find out the changing rules of AAM in coffee and find effective measures to reduce AAM generation in coffee to ensure the safety of coffee products.Taking coffee as the research object,the changes of AAM content during roasting and the effects of antioxidants on AAM in simulated system and coffee beans were studied.The main contents of this paper are as follows:(1)Changes of AAM and its key components in coffee during roasting.The contents of AAM,5-hydroxymethylfurfural,fructose and glucose increased at first and then decreased,while the contents of sucrose and free amino acids decreased gradually.AAM content reached the maximum value(974.25 ± 29.29 μg/kg)when the temperature rose to 180 °C.The results showed that the production of AAM was positively correlated with glucose,fructose and 5-HMF,and negatively correlated with sucrose and Asn(p < 0.01).(2)The effect of free amino acids on the production of AAM by Asn-sugar pathway.In the constructed Asn-FGS simulation system,the production of AAM increased in the experimental group with 8 kinds of amino acids(tryptophan,alanine,phenylalanine,cysteine,glutamine,arginine,serine,lysine)heated at 180 °C for 5 min.However,the promotion effect became weaker as heating time extended.When heated at 180 °C for5 min,10 min,and 15 min,both glycine and aspartic acid exerted an inhibitory effect on AAM production.(3)The effect of antioxidants on AAM formation in simulated system.In the simulation system constructed by the actual proportion of sugar and free amino acid components in raw coffee beans,the five antioxidants had significant inhibitory effect on AAM production at the optimal inhibitory concentration(p < 0.05).Among them,ascorbic acid had the best inhibitory effect.The inhibitory rate was 59.42% when the concentration of ascorbic acid was 100 μmol/ m L.When the concentration of citric acid and gallic acid was 500 μmol/m L,the inhibition rate was 54.95% and 34.64%,respectively.The inhibitory effect of rosmarinic acid and luteolin on AAM was weak.(4)Study on the inhibitory effect of ascorbic acid on AAM in roasted coffee.Coffee beans were treated with ascorbic acid solution(50 g coffee beans was soaked in100 m L solution).Through single factor and response surface tests,the best treatment conditions for ascorbic acid to inhibit AAM were determined with AAM inhibition rate and sensory score as indexes.The results showed that the concentration of ascorbic acid was 150 μmol/m L,the soaking temperature was 35 °C and the soaking time was 4 h.Under the optimum conditions,the inhibition rate of AAM could reach 52.63%.