A object of the present invention is to provide a novel system whereby an enteral nutrient or an enriched liquid food can be solidified so that it can be easily administered within a short period of time without liguefying in the body to thereby lighten a care-giver's burden in tube feeding such as gastrostomic feeding. As the results of studies, it is found out that such a nutrient or an enriched liquid food can be quickly thickened or solidified at a temperature of 40° C. or below by using a starch adhesive, which contains as the main component sodium iota-carrageenan, sodium kappa-carrageenan, sodium lambda-carrageenan or a mixture thereof, without dissolving the starch adhesive by heating. Further, it was confirmed that it is an administration method almost free from water liberation when the solidified product was administered from a syringe, thus the present invention was completed. That is, the use of the above carrageenan as a starch adhesive (a semi-solidifying agent) makes it possible to produce the desired semi-solidified enteral nutrient as described above.
