When looking for reliable vegetarian alternatives to gelatin that can withstand outdoor summer heat, agar agar is definitely your best option. Unlike traditional gelatin, agar agar is derived from seaweed and has a much higher melting point, meaning it will stay firm even when sitting outside at a backyard barbecue.
For fruit jellies and panna cotta, the standard ratio is generally about 1 teaspoon of agar powder per cup of liquid. However, keep in mind that agar requires boiling to activate its gelling properties. You will need to boil the liquid mixture for about one to two minutes before pouring it into your molds.
Pectin is another common alternative, but it behaves differently. Pectin works best with high sugar and acid contents, making it ideal for fruit jams and glazes rather than dairy-based desserts like panna cotta. Both ingredients are widely available in the baking aisle of most standard supermarkets.