A frothing oil-in-water emulsion having excellent heat resistance and good meltability on the tongue, freshness and coolness, and a fat composition most suited for the production thereof. The composition is prepared by mixing a lauric fat or a hardened oil thereof with a C16-C24 fatty acid or its ester or a fat rich in glycerides having C16-C24 fatty acid residues, effecting the transesterification of the obtained mixture by the well-known method in the presence of a lipase having a specificity for the 1- and 3-positions of glycerides, and if necessary conducting extreme hardening by the conventional method, whereby a fat composition comprising glycerides having the total number of the carbon atoms of the constituent fatty acid residues of 38 or less, 42 to 46, and 48 or above, respectively, in amounts of 25-50 %, 25-40 %, and 5-25 %. The emulsion is prepared from this composition.