The kinetics of colour degradation,chlorophylls and xanthophylls loss in pistachio nuts during roasting process  

作　　者：Ali Dini Soudeh Khanamani Falahati-pour Khosro Behmaram Nasser Sedaghat 

机构地区：[1]Pistachio Safety Research Center,Rafsanjan University of Medical Sciences,Rafsanjan,Iran [2]Department of Food Science,Engineering and Technology,Faculty of Agricultural,Ferdowsi University of Mashhad(FUM),Mashhad,Iran

出　　处：《Food Quality and Safety》2019年第4期251-263,共13页食品品质与安全研究（英文版）

基　　金：Rafsanjan University of Medical Sciences,Rafsanjan,Iran,under the ethical code of IR.RUMS.REC.1397.150 at Rafsanjan University of Medical Sciences.

摘　　要：Objectives:Colour is amongst the parameter which is used for process control during roasting.Materials and Methods:In this study,the effects of hot air roasting temperature(120,130,145,160,and 170°C)and hot air velocity(0.6,1.3,and 2 m/s)on colour change kinetics of pistachio nuts were investigated by employing image analysis and simultaneously chlorophylls and xanthophylls(lutein andβ-carotenoid)concentration were determined by spectrophotometric measurement method.Results:We found that roasting temperature and hot air velocity had significant effect on colour changes.There is a correlation between a-and b-value with chlorophylls and xanthophylls concentration,respectively.The roasting temperature was found to be the main factor affecting colour development.The variations in the pigments concentration and colour parameters of pistachio nuts were adequately simulated by quadratic and cubic polynomials.The changes in L-,b-values,and xanthophylls degradation were well-fitted to the first-order kinetic model while a-value and chlorophylls degradation followed the zero-order kinetic.The activation energy was determined at 113.9,116.7,and 117.2 kJ/mol with R2≥99.9 and 191,195,and 163.2 kJ/mol with R2≥99.5 and 73.7,71.3,and 81.6 kJ/mol with R2≥99.9 for L-,b-,and a-value in hot air velocity of 0.6,1.3,and 2 m/s,respectively.Conclusions:Activation energy of chlorophylls and xanthophylls degradation were in the range of the activation energy for the yellowness(b-value)and redness(a-value)reactions.

关 键 词：colour kinetics roasting process pistachio nuts imaging analysis 

分 类 号：P31[天文地球—固体地球物理学]