Abstract:To identify the most suitable carrier material and drying technology to reduce or even prevent stickiness during spray-drying of instant Chinese chestnut flour, the effects of different concentrations of carrier materials, such as maltodextrin, whey protein isolate, acacia gum, and β-cyclodextrin, on spray drying were studied. The optimum parameters during spray drying were determined in orthogonal experiments, and the properties of the instant flours were evaluated. The results showed that the optimal conditions for spray drying are as follows: inlet temperature, 190 ℃; feed rate, 20 mL/min; and 5% maltodextrin as a carrier. Range analysis and variance analysis revealed that the factors most affecting product yield are (in descending order): carrier addition, feed rate, and inlet temperature. The water and fat contents of the instant chestnut flour were as low as 1.60 g/100 g and 1.77 g/100 g, respectively, while the protein content was as high as 8.45 g/100 g. The whiteness was 82.18. A total of 38 volatile aroma components were identified, and acids, alkanes, and aldehydes accounted for 42.47%, 19.87%, and 16.81%, respectively, of the total volatile contents. Six key aroma compounds were identified by calculating the odor activity values (OAVs): hexanal, nonanal, (E,E)-2, 4-nonadienal, D-limonene, hexanoic acid, and ethyl maltol. The Instant Chinese chestnut flour produced is nutritionally rich, with a pleasant color, strong flavor, and good tonality and stability.
