Abstract: High- temperature modification of insoluble dietary fiber from lotus seedpod( LIDF) was optimized by response surface methodology. Effects of modification on the physicochemical properties and application of LIDF were analyzed. The content of soluble dietary fiber( SDF) was used as the evaluation index for technology optimization.The optimized technological parameters were as follows: ratio of material to liquid 1 ∶ 6.75( g / m L),processing temperature 115 ℃,and processing time40 min. Under this condition,the modified LIDF contains 4.33% SDF. Physicochemical analysis confirmed that high temperature modification could significantly enhance the swelling rate,eater binding capacity and adsorption capacity on sodium cholate of LIDF( p < 0.05),but the oil- holding capacity were obviously decreased( p < 0.05).In addition,the microstructure of LIDF was changed to be peeled layers.The addition of LIDF could significantly improve the hardness and cohesion of noodles( p < 0.05),but showed insignificant effect on the hardness and brittleness of biscuit( p > 0.05).Adding 3% ~5% modified LIDF in noodles,or 6% ~ 8% in biscuit did not significantly change the texture of products( p > 0.05). The adding of LIDF could enhance the bitterness,astringency,and aftertaste- B of product,but the modification was on the contrary. The results indicated that high- temperature modification could increase the application value of LIDF as nutrient supplement in noodle and biscuit.