Grenadine

Ingredients

1 cup syrup:

• 113 g pomegranate juice (1/2 cup, 150 g seeds)
• 100 g sugar (just less than 1/2 cup)

Directions

• Combine juice and sugar.

• Keep at room temperature, stirring occasionally, until the sugar dissolves completely. Expect this to take several hours.

• Store in the refrigerator or freezer, preferably in an air-tight container.
  Expect a shelf-life of 3-6 months.

Notes

• [1] calls for some fancier ingredients too, but "pomegranate simple syrup" seems to be a common way to make grenadine.

• A commenter in [1] points out that it's best to avoid heating juice if possible, since doing so can affect the flavor. [2] also mentions that heating can cause sucrose to split into glucose and fructose, which affects flavor (and texture). These concerns make sense to me, so I modified the recipe to avoid heating.

• The first time I made this, I measured that 1/2 cup fresh-squeezed pomegranate juice weighs 112 g. That's 224 g/cup, which is almost identical to the density of water, which is 227 g/cup. Going forward, I'll just assume that pomegranate juice and water have the same density.

• According to the USDA, 100 g of 100% pomegranate juice has 12.6 g of sugar [3]. This is accounted for in the "1 cup" recipe above. The goal is to have a total of 200 g of sugar (see below for more details). The juice itself accounts for 14 g of sugar, so only 186 g needs to be added.

• "Rich" vs "simple" syrup:

  • This recipe was originally a "rich" syrup, or a 2:1 v/v ratio of sugar to water. Because water is slightly more dense than sugar, this corresponds to a 1.762:1 m/m ratio (e.g. 186 g sugar to 113 g juice). Note that this is relatively close to the solubility limit of sugar in water, which is 2000 g/L, or a 2:1 m/m ratio.

  • Rich syrups have significantly longer shelf life than "simple" syrups (1:1 v/v ratio), because they have less free water. This inhibits microbial growth. However, [2] mentions that cold-processing can reduce shelf life, because the boiling step kills any microbes present in the syrup to begin with.

  • 2024/11/02: I decided to switch the recipe to simple syrup:

    • With the rich recipe, I never got all the sugar to dissolve, even after several days.
    • Cocktail recipes all assume that grenadine is a simple syrup, and it's a pain to try to adjust for that.

Reference

[1] https://www.liquor.com/grenadine-recipe-5071284 [2] https://www.seriouseats.com/cocktail-science-simple-syrup-do-not-cook-it-unheated-cool-sugar-syrup-for-drinks [3] https://fdc.nal.usda.gov/fdc-app.html#/food-details/2344824/nutrients