Hot-water-sterilized packaging and method for producing same

A hot-water sterilized package, comprising a container filled with contents, wherein

• the container comprises a barrier layer,
• the barrier layer comprises 96 mass % or more of a modified ethylene-vinyl alcohol copolymer based on a total amount of resin,
• the modified ethylene-vinyl alcohol copolymer is represented by a formula (I), contents (mol %) of a, b, and c based on the total monomer units satisfy formulae (1) through (3), a degree of saponification (DS) defined by a formula (4) is 99 mol % or more, and in measurement using a differential scanning calorimeter (DSC), crystalline melting enthalpy (ΔHA:
• J/g) during temperature rise in a hydrated state, wherein the hydrated state is produced by sterilization at a temperature from 60° C. to 140° C. in the presence of moisture, and crystalline melting enthalpy (ΔHB:
• J/g) during temperature rise after drying and melting followed by rapid cooling satisfy formulae (5) and (6), wherein measurement by DSC is performed by raising the temperature from 30° C. to 241° C. at a rate of 10° C./min., followed by rapid cooling to 92° C. at 10° C/min;
• wherein in the formula (I), each of R1, R2, R3, and R4 is a hydrogen atom and each of X, Y, and Z independently denotes a hydrogen atom, a formyl group, or an alkanoyl group having a carbon number from 2 to 10
• 22≤a≤40 (1)
• 0.2≤c≤1.5 (2)
• [100−(a+c)]×0.9≤b≤[100−(a+c)] (3)
• DS=[(Total Number of Moles of Hydrogen Atoms in X,Y, and Z)/(Total Number of Moles of X,Y, and Z)]×100 (4)
• ΔHA/ΔHB≥0.5 (5)
• ΔHB≥70 (6);
• and
• wherein the package has a lower oxygen transmission rate after hot-water sterilization compared to the oxygen transmission before hot-water sterilization.