The effect of different methods of roasting on the physico-chemical properties of wild almond

Document Type : Research Article


1 PhD student, Dept. of Food Process Engineering, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran

2 Associate Professor, Food Process Engineering Gorgan University of Agricultural Sciences & Natural Resources, Iran


Roasting is one of the important processing methods which is widely used in the nut industry to improve the flavor, color, texture and overall acceptability. In this study, four different roasting methods (superheated steam, hot-air, frying and infrared) were applied to roast wild almond kernels. Effect of processing conditions including air and oil temperatures (160 and 180°C), infrared power (200 W, 300 W) during roasting (15, 25 and 35 min) on moisture content, chemical properties, color and sensory properties were investigated. The results showed that increasing the temperature in hot air roasting, infrared power and roasting time decreased pH and the moisture content. The highest moisture content and acidity was for superheated steam and infrared roasting, respectively. Frying roasting showed the highest total acceptance while infrared roasting (300 W and 35 time) showed the minimum acceptance. Finally, infrared (200 W, 15 min), hot-air (160 ͦ C, 15 min) and frying (160 ͦ C, 25 min) were the recommendable processes for the wild almond roasting.

Graphical Abstract

The effect of different methods of roasting on the physico-chemical properties of wild almond


  • Improving the sensory and physico-chemical properties of wild almond with appropriate roasting process.
  • Studying four different methods of roasting including superheated steam, hot-air, frying and infrared methods.
  • Browning index, soluble solid content and color were affected by the intensity of applied roasting process (power in infrared method and temperature in other methods).
  • pH, soluble solid content and color were significantly influenced during different roasting methods.
  • The highest moisture content and pH of wild almonds have observed in the samples treated by superheated steam and infrared roaster, respectively.  
  • The maximum and minimum score of total acceptance in sensory evaluation was correlated to the frying and infrared roasting.

Regarding the physicochemical properties and sensory evaluation, infrared, hot air, frying and superheated steam roasting were respectively chosen for roasting of wild almond


Main Subjects

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