Escaping the Flab: Why Colombard Is the White Grape Built for Tropical Thailand

The central challenge of making white wine in a tropical climate is invisible. It happens inside the berry, in the weeks before harvest, as heat dismantles the biochemical balance that determines whether a wine has life in the glass or simply collapses into sweetness.

At Skugga Estate in Mae On, Chiang Mai, the answer to that challenge is Colombard: a variety with an unusual genetic heritage, a track record in heat, and a natural resistance to the acid loss that makes tropical white wine production so technically demanding.

The Biochemical War Inside the Berry

In a temperate climate, ripening is a gradual process. Sugars accumulate slowly while acids decline at a rate the winemaker can work with. The two curves move in proportion, and harvest timing is a matter of finding the balance point where flavour development, sugar concentration, and acid retention converge.

In the tropics, that balance is disrupted by heat.

Elevated temperatures accelerate the photosynthetic production of sugars dramatically. If a winemaker waits for full flavour development, sugar levels spike to the point where fermentation produces a wine with excessive, unbalanced alcohol. That is the first problem.

The second is more damaging. Wine grape acidity is primarily composed of two organic acids: tartaric acid, which is relatively stable, and malic acid, which is not. Malic acid is actively consumed by the berry as an energy source through cellular respiration. When ambient temperatures exceed 30°C, that respiration accelerates sharply, causing total acidity to fall. The hotter the environment and the longer the fruit hangs, the more malic acid is lost.

The intersection of accelerated sugar accumulation and rapid acid depletion produces what winemakers call a flabby wine: high in alcohol, low in titratable acidity, high in pH, and lacking the structural tension that makes white wine refreshing and food-compatible. Flabby wine also has a practical problem beyond flavour. A high pH reduces the efficacy of the sulfites used to protect wine from oxidation and microbial spoilage, making the wine more fragile in bottle.

In a tropical climate, acid retention is not a stylistic preference. It is the technical precondition for making a wine that holds together.

Why Colombard

Colombard is the direct genetic offspring of a cross between Gouais Blanc and Chenin Blanc. That parentage matters. Gouais Blanc is a prolific, high-vigour parent known for imparting resilience and productivity. Chenin Blanc is one of the world's most acid-retentive white varieties, capable of maintaining fierce natural acidity even in warm growing conditions.

The result is a variety that was historically prized not as a table wine grape but as the foundational raw material for Cognac and Armagnac distillation, precisely because it holds acidity at levels other varieties lose in comparable growing conditions. That structural quality is exactly what tropical viticulture needs.

In its native southwest France, Colombard is considered a relatively neutral variety, valued for yield and acid rather than aromatic intensity. What makes it particularly interesting for Mae On is what happens when that acid structure encounters Thailand's solar radiation and tropical heat.

What Tropical Colombard Tastes Like

The environmental stressors of highland Thai viticulture push Colombard's aromatic expression well beyond the restrained profile it shows in cooler French climates. Rather than suppressing the variety's character, the intense solar radiation of Mae On drives a biochemical shift that produces a lifted, expressive aromatic bouquet: ripe gooseberry, crisp green apple, passionfruit, white peach, and vibrant lemongrass, with subtle floral undertones that reflect the variety's Chenin Blanc heritage.

On the palate, tropical Colombard carries a punchy, tropical fruit core, primarily lemon, guava, and grapefruit, anchored by the tight, resilient acidity that the variety's genetics preserve even under heat stress. That acidity prevents any sensation of flatness, gives the wine substantial length, and produces a dry, clean finish rather than the cloying sweetness that a lower-acid variety in the same conditions would leave behind.

The food compatibility implications are significant. High-acid white wines with tropical fruit character are one of the most effective pairings for the complex, spice-forward flavours of Thai cuisine. The acid cuts through the richness of green curry, balances the heat and fat in dishes like khao soi, and provides the structural counterpoint that makes the pairing work technically rather than simply as a matter of convention.

Field Grafting: Colombard onto Established Root Systems

To introduce Colombard at scale into the Mae On vineyard, Skugga Estate is planning the field grafting of approximately 250 vines. Rather than uprooting existing plants and waiting for new saplings to establish, field grafting, also called top-working, involves removing the canopy of an existing vine and grafting the new scion variety directly onto the mature trunk.

The advantage is immediate access to an established root system. A field-grafted scion does not need to develop the root infrastructure that a newly planted vine requires years to build. It is connected from day one to a mature, deep-rooted network, which drives rapid and vigorous new shoot growth and brings the vine into production significantly faster than replanting would allow.

At Skugga Estate, that root system is the IAC 572 rootstock already in the ground, selected specifically for its nematode resistance, acid soil adaptation, and acidity-inducing properties in tropical conditions. Colombard's genetic resistance to malic acid loss is reinforced at the root level by IAC 572's demonstrated ability to induce greater titratable acidity in the fruit. The two properties work in the same direction.

The estate's permaculture farming approach provides a further layer of acid protection. Heavy organic mulch applied around the vine base insulates the soil surface from direct solar radiation, lowering root zone temperatures relative to ambient air. Keeping the root system cooler reduces systemic heat stress on the vine, which further decelerates the metabolic respiration of malic acid in the fruit during the ripening period. It is a small intervention with a measurable effect on the acid profile at harvest.

Colombard in the Context of the Estate's Wine Programme

Colombard will be the primary white variety in Skugga Estate's developing wine programme, joining Pokdum and Shiraz as the core of the estate's varietal selection. Its selection reflects the same logic that underpins the estate's approach to red varieties: choose grapes whose specific genetic properties are suited to the conditions rather than forcing varieties that require extensive chemical or technical intervention to survive them.

Skugga Estate's wine programme is developing as the vines mature following planting in 2025. To visit the vineyard and learn more about the estate's growing programme, book a tasting experience at Skugga Estate or contact the team at vineyard@skuggalife.com.

Further reading on the estate's wine programme: How the Mae On Climate Shapes Tropical Viticulture, The Pokdum Grape: Thailand's Native Wine Variety, The Soils of Mae On: Decoding Thai Terroir, Cultivating Shiraz in the Tropical Highlands of Mae On, How the IAC 572 Rootstock Powers Skugga Estate, and How Tropical Viticulture Rewrites the Farming Playbook.

Frequently Asked Questions

What is Colombard and why is it suited to tropical viticulture?

Colombard is a white wine grape variety that is the genetic offspring of Gouais Blanc and Chenin Blanc. It is historically valued for its high natural acidity, which made it the foundational grape for Cognac and Armagnac distillation in southwest France. In tropical viticulture, that acid retention is its primary asset. Colombard exhibits a lower rate of malic acid degradation under heat stress than most white varieties, making it one of the most structurally suitable white grapes for high-temperature growing conditions.

What does flabby wine mean and why is it a problem in tropical climates?

Flabby is an enological term for wine with insufficient natural acidity, characterised chemically by low titratable acidity and high pH. In sensory terms, a flabby wine feels heavy, syrupy, and flat rather than crisp and refreshing. In tropical climates, heat accelerates the loss of malic acid in the ripening berry through cellular respiration, making flabbiness a structural risk for any variety that does not retain acid well under temperature stress. A high pH also reduces the efficacy of sulfites used to protect the wine from oxidation and microbial spoilage.

What is field grafting and why is Skugga Estate using it for Colombard?

Field grafting, also called top-working, involves removing the canopy of an existing vine and grafting a new scion variety directly onto the mature trunk. The grafted scion gains immediate access to an established root system, driving rapid vegetative growth and bringing the vine into production faster than replanting from scratch. At Skugga Estate, Colombard scions will be field-grafted onto the IAC 572 root systems already established in the vineyard, combining Colombard's genetic acid retention with IAC 572's acidity-inducing properties in the fruit.

How does Colombard pair with Thai food? 

Tropical Colombard's combination of high natural acidity and vibrant tropical fruit character, primarily lemon, guava, grapefruit, and passionfruit, makes it an effective pairing for Thai cuisine. The acidity cuts through the richness and fat in dishes like green curry and khao soi, and provides structural contrast to the heat and spice of dishes like som tam. High-acid white wines with tropical fruit profiles are among the most food-compatible styles for Southeast Asian cooking.

How does organic mulching help preserve acidity in Colombard grapes?

Applying heavy organic mulch around the vine base insulates the soil surface from direct solar radiation, lowering root zone temperatures relative to ambient air temperature. Keeping the root system cooler reduces systemic heat stress across the vine, which decelerates the rate of malic acid respiration in the developing fruit during the ripening period. Combined with Colombard's genetic resistance to acid loss and IAC 572's acidity-inducing properties, organic mulching provides an additional layer of acid retention management at minimal cost.