Fruit Intelligence: Kumquat

By Michael Laiskonis, Culinary Director, Boiron Americas

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If there is a silver lining to the cold and dark winter months, perhaps it’s the appearance of peak-season citrus fruits to brighten our kitchens with flavors from sunnier domains.

While lemons, limes and oranges are firmly evergreen in their use, this peak season allows specialty citrus its time to shine – from spicy sudachi and floral bergamot to sweet blood orange and zesty kalamansi – among many other specimens, familiar and exotic. A favorite of mine, and a bit of an outlier among the citrus family, is kumquat. While botanists may argue its precise origin and taxonomic classification, for pastry chefs its unique quality is the practice of consuming the whole fruit – both the sweet rind and the tart juicy flesh within.

I am excited to introduce kumquat as the latest addition to Les verger Boiron’s citrus fruit family a puree with a high aromatic intensity and complex balance of sweetness, acidity and bitterness, all supported by a range of characteristic citrus notes. Its introduction as a puree – with visible specks of rind – opens up a wealth of opportunity for use in pastry applications.

First cultivated in Asia, our kumquats can be traced to the sun-drenched region of Andalusia, not far from the Strait of Gibraltar and the rugged wilderness of Los Alcornocales Natural Park. It’s here in the mountainous region of southern Spain where Boiron sources the Nagami kumquat. This small, oval-shaped variety is grown on a family-run farm that specializes in the fruit. Such focus is a rarity in citrus agriculture and offers us both high quality and consistent supply. Our producer partner practices certified organic methods, which is an essential factor when processing whole fruits such as kumquat. Hand-picked, fully mature kumquats offer the most complex flavor profile; the harvest season in Spain begins in February and lasts through April.

Kumquat pairs well with a wide array of complimentary fruits: mango, pineapple, strawberry, pear, blackcurrant, quince and coconut. The bold flavor stands up to buttery caramel, fragrant vanilla, honey, subtle hints of spice and chocolate – not to mention, pistachio, hazelnut and chestnut.

In kumquat’s fresh form, its applications in the pastry kitchen are often limited to candying and simple preserves, but kumquat puree allows for convenience, control and creativity in preparations from sorbet and mousse to cremeux and confections. A few of my favorite recipes include a kumquat and mango-topped pistachio financier, kumquat pâte de fruit accented with pineapple, and a sorbet pairing kumquat with Corsican clementine.

For more recipe inspiration and technical information on Les vergers Boiron’s Kumquat purée, visit: https://www.les-vergers-boiron.com and follow along as we explore all of our flavors, origins, and applications at @les_vergers_boiron_americas

Kumquat Clementine Sorbet

By Michael Laiskonis, Culinary Director, Les vergers Boiron

Because kumquat puree has a high solid content, I like to introduce other fruits to help balance the formulation and create a broader, more complex flavor profile.

Yield: 1 liter sorbet

• 140 g granulated sugar, divided
• 3 g sorbet stabilizer
• 195 g water
• 45 g glucose powder
• 150 g Les vergers Boiron PGI Corsican Clementine purée
• 350 g Les vergers Boiron Kumquat purée

1. Combine 20 grams of the of sugar with the stabilizer. Reserve.
2. In a saucepan, heat the water to 120°F (50°C.) Whisk in the stabilizer mixture, followed by the remaining 120 grams of sugar and the glucose powder. Bring just to a boil and remove from heat.
3. Chill and allow the syrup to mature for at least 4 hours.
4. Combine the purées and syrup and process in a batch freezer.
5. Extract the mix at 23°F (-5°C). Alternatively, transfer to PacoJet canisters and freeze; process as needed.
6. Continue to harden the sorbet at 0°F (-18°C) as necessary.

Kumquat Pate de Fruit

By Michael Laiskonis, Culinary Director, Les vergers Boiron

When preparing pâte de fruit, I like to use a medium-set pectin. During the cooking process, the sugar and glucose must be added slowly to ensure the cooking temperature does not fall below 85°C (185°F). This will prevent the pectin from setting prematurely and compromising the final texture. If desired, add 10 grams of corresponding fruit liqueur at the end of the cooking stage.

Yield: 50 pieces pâte de fruit

• 300 g Les vergers Boiron Kumquat purée
• 100 g Les vergers Boiron Pineapple purée
• 580 g granulated sugar  
• 9 g yellow pectin
• 80 g glucose syrup
• 12 g citric acid solution

1. Place the purée into a large, heavy saucepan and heat to 104°F (40°C).
2. Combine 60 grams of the sugar with the pectin and whisk into the purée. 
3. Bring to a boil over medium heat, stirring continually.
4. Add the remaining 520 grams of the sugar along with the glucose in multiple additions.
5. Continue to cook to a final temperature of 223°F (106°C).
6. Remove from heat and stir in the citric acid.
7. Immediately pour into prepared frames or deposit into silicon molds and allow to cool and set at room temperature.
8. To serve, toss the cut or unmolded candies in citric sugar (below).

Citric Sugar

• 100 g sugar
• 4g citric acid

1. Thoroughly combine the sugar and citric acid. Store in a sealed container.

Kumquat Pistachio Financier

By Michael Laiskonis, Culinary Director, Les vergers Boiron

A fluid gel is a versatile component that can be used in several ways, from garnishing cakes and pastries to plated desserts. The sweetness can be adjusted to taste. For more acidity, replace a portion of the liquid with lime, passion fruit or similar acidic fruit.

Yield: 48 financiers

Kumquat-Mango Fluid Gel

• 150 g Les vergers Boiron Kumquat purée
• 70 g Les vergers Boiron Mango purée
• 100 g granulated sugar
• 100 g water
• 4 g agar agar

1. Combine the purées and sugar and gently warm to 95°F (35°C). Reserve.
2. Combine the water and agar agar in a small saucepan and bring to a boil over medium heat.
3. Reduce the heat and hold a simmer for 30 seconds.
4. Remove from heat and stir in the purée mixture. Allow to cool and set to a firm gel at room temperature.
5. Break up the gel and place it into a variable-speed blender. Process until smooth. Transfer to a squeeze bottle.

Pistachio Financier

• 140 g unsalted butter
• 45 g almond flour
• 45 g all-purpose flour
• 115 g confectioner’s sugar
• 1 g salt
• 125 g egg whites
• 40 g pistachio paste

1. In a small saucepan, gently cook the butter until lightly browned, whisking occasionally; reserve and keep warm.
2. Meanwhile, combine the almond flour, all-purpose flour, confectioner’s sugar and salt.
3. In a large mixing bowl, manually whip the egg whites just until frothy. 
4. Whisk in the almond flour mixture.
5. Slowly whisk in the warm brown butter, followed by the pistachio paste, ensuring complete emulsification.
6. Transfer the batter to a pastry bag then pipe it into sprayed silicon molds. Chill for 10 minutes.

(This article appeared in the Winter 2025 issue of Pastry Arts Magazine)