Effects Of Several Additives And Legume Flours On Acrylamide And Hydroxymethylfurfural Formation In A Maillard System

Acrylamide and hydroxymethylfurfural (HMF) are food endogenous harmful substancesproduced during high-temperature processing. In this research, effects of chlorogenic acid, sevenlegumes and four additives on the formation of acrylamide and hydroxymethylfurfural inasparagine/glucose model reaction system were investigated. The main results were as follows:1. Effects of chlorogenic acid and its quinone derivative on acrylamide andhydroxymethylfurfural formation in asparagine/glucose model reaction systemQuinone derivative of chlorogenic acid was prepared using polyphenol oxidase (tyrosineoxidase). Chlorogenic acid or its quinone derivative were added in an equimolarasparagine/glucose model system and heated at160℃for15min. It was found that the additionof chlorogenic acid significantly increased acrylamide formation and inhibited its elimination. Incontrast, the quinone derivative of chlorogenic acid decreased acrylamide formation. Also, theaddition of chlorogenic acid increased HMF formation whileits quinone form decreased itsformation; however, the quinone chlorogenic acid showed less effective on decreasing of theformation of HMF than that of acrylamide.Three mechanisms may be involved for increasing acrylamide formation by chlorogenicacid. Firstly, it increased the formation of HMF, which acts as a more efficient precursor thanglucose to form acrylamide. Secondly, it decreased the activation energy for conversion of3-aminopropionammide (3-APA) to acrylamide, and enhanced deamination from3-APA. Andthirdly, it prevented attack of the produced acrylamide from free radicals by keeping high redoxpotential during the Maillard reaction.2. Effects of seven legume flours on acrylamide and hydroxymethylfurfural formation inasparagine/glucose model reaction systemSeven legume flours were added into an equimolar asparagine/glucose model system, and heatedat160℃for15min. The whole flour from five of seven varieties decreased formation ofacylamide (inhibition rate: black soybean54.9%, yellow soybean47.4%, yellow pea21.0%,mungbean16.5%, and lentil10.3%). The whole flour of chickpea and green pea increased acrylamide formation. All whole flour of seven legumes increased HMF formation. Defattedflours and defatted-dehulled flours decreased acrylamide formation with bigger inhibitioncapacity, and increased HMF formation. Defatted legume flours of5legumes(black soybean,chickpea, green pea, lentil, yellow soybean) eliminated the formed acrylamide, defatted yellowsoybean flour elimination rate was up to28.5%.3. Effects of several additives on acrylamide and hydroxymethylfurfural formation inasparagine/glucose model reaction systemGlycine, CaCl2, cysteine and cysteine monohydrochloride alone or in mixture were used to testtheir effects on the formation of acrylamide and HMF in an equimolar asparagine/glucose modelsystem (heated at160℃for15min). It was shown that the addition of these additives alonedecreased acrylamide formation, the inhibition capacity ranked in decreasing order as: cysteine,cysteine monohydrochloride, CaCl2, glycine. As for HMF, CaCl2significantly increased HMFfomation, while glycine, cysteine and cysteine monohydrochloride significantly inhibited itsformation. The addition of glycine along with CaCl2did not decrease acrylamide and HMFformation at the same time, while the mixture of cysteine and CaCl2, the mixture of glycine andcysteine or the mixture of CaCl2and cysteine monohydrochloride did.Adding the mixture of0.8mmol CaCl2and1.2mmol cysteine and the mixture of1.0mmol glycine and1.0mmol cysteinedecreased acrylamide and HMF formation at the same time with inhibition rate higher than90%.