
Passion fruit liqueur is a tropical fruit liqueur made by blending passion fruit juice or pulp with a spirit base and sugar.
Nothing else gives that musky aroma, so a swap holds the sweetness and the strength and changes the fruit. Whatever you use, check the strength: this bottle carries about 17%.
Passion fruit purée or juice
Purée and juice give the fruit without the alcohol and with less sugar. Both need the strength making up and the sweetening rechecked. It brings back the aroma and the acidity and none of the strength, so the drink needs neutral spirit made up roughly on par with the syrup.
A brand inside the same category, sweeter and brighter in color: it covers the flavor, and the drink wants about a third less of its own sugar.
Passion fruit is built on sulfur-bearing esters that are extraordinary when fresh and disappear quickly. This is a bottle to buy small. Six months open and it reads as generic tropical sweetness.