The objectives of this study were to (1) determine sugars, fructo-oligosaccharides (FOS) and inulin-type fructans of Jerusalem artichoke tuber (JAT) powder and JAT inulin extract; (2) compare the chemical compositions of JAT powder and JAT inulin powder; and (3) investigate the effect of fortifying JAT inulin powder into various commercial products on the sensorial characteristics of products. The result showed that after hot water extraction, the amounts of sugars, FOS and inulin-type fructans in JAT inulin extract significantly increased (P < 0.05) when compared with those of JAT powder. Protein and total dietary fiber contents in JAT inulin powder decreased around 1.6 and 5.7 times comparing with JAT powder. The result of fortifying JAT inulin powder into four commercial products such as rice porridge, instant cereal drink, ready mixed soya powder and chocolate malt mixed beverage showed that the addition of inulin lessened the sensorial scores of all products. JAT contains health promoting compounds such as inulin and FOS which can be applied in food as dietary fiber supplement and prebiotics. The process of inulin production from JAT was developed and might be applied in the food industry. The consumption of inulin and FOS of 5–15 g/day has been reported to be beneficial to human health and showed evidence of prebiotic activity. At present, inulin was fortified in various kinds of commercial food products in Thailand. Therefore, it was interesting to fortify minimum recommended inulin daily intake of 5 g per serving size of commercial products. The sensorial evaluation results of samples fortified with JAT inulin in this study provided useful information for product development to be realized before commercially launching these JAT inulin fortified products to the market. Moreover, the JAT powder produced from grinding dried JAT could be sold as a food supplement due to its inulin and other nutrient contents.

In this study, inulin was extracted from Jerusalem artichoke tuber (JAT) powder and then concentrated before spray drying. The aims of this study were to (1) determine the drying condition that provided high powder yield together with superior qualities of JAT inulin powder and (2) investigate the chemical and physical properties of inulin powder. The inulin extracts at different concentrations of 10, 20, and 30 °Brix were spray-dried and then compared. The spray drying experiments were conducted at the inlet/outlet air temperatures of 150/90, 170/90, and 190/90 °C for the chosen concentration of inulin extract. It appeared that spray drying of the 30 °Brix extract at the inlet/outlet drying air temperatures of 190/90 °C resulted in the highest value of powder recovery, bulk density, water solubility and the lowest moisture content and hygroscopicity in comparison with its counterparts. SEM micrographs showed that the powder produced by this condition was more stable and less sticky than others. The sugars, total fructo-oligosaccharides (1-kestose, nystose, and 1^F-β-fructofuranosyl nystose) and inulin-type fructans contents of powder were 12.88, 11.12, and 64.36 g/100 g of powder, respectively. The moisture sorption data and models developed in this work could be used for determining the suitable condition of surrounding air for inulin powder storage.