At What Temperature Does Pekmez Reach the Right Consistency?

Pekmez, or grape molasses, is made by boiling grape must until the liquid reaches 104–105°C / 220°F. This is a few °C above water's boiling point at sea level, 100°C / 212°F, and indicates that the sugar has become more concentrated.

Why does temperature indicate sugar concentration? As the proportion of sugar in water increases, the boiling point rises. This principle is commonly used in candy making and syrup production. The target temperature of 104–105°C / 220°F for pekmez corresponds to a sugar concentration of about 70–75%, giving it a thick but pourable consistency.

How can you tell without a thermometer? You can use the cold-plate test: drop a little grape must onto a cold plate, wait a few seconds, and push it with a finger. If it wrinkles, it has reached the right consistency. This remains the most reliable method for traditional pekmez making when temperature cannot be measured. The total boiling time is usually 2–3 hours, depending on the starting concentration of the must and the amount being boiled. In large traditional cauldrons, it can take 4–5 hours.

Why is clay or wood-ash water added? In traditional pekmez making, clay or wood-ash water is added to the must to neutralize its acidity and help it clarify. This step does not directly affect the boiling time, but can improve the color and clarity of the final product. This step is often skipped in home production.

What happens if it boils too long? Boiling above 106–107°C / 225°F can make pekmez excessively thick, nearly solid once cooled and too firm to take with a spoon. Over-boiled pekmez can be heated with a small amount of water to make it pourable again, though its original flavor may change somewhat.

What happens if it is under-boiled? Pekmez removed from the heat below 103°C / 217°F may not be thick enough and can ferment and turn sour over time. Stopping before it reaches the target temperature shortens its shelf life. If under-boiled pekmez starts to foam within a few weeks, this is a sign of fermentation; boil it again until it reaches the target temperature.

Which grape varieties are best? Ripe, sweet grape varieties with a high sugar content, such as seedless grapes or köknar grapes, are preferred for pekmez. Sour or low-sugar grapes take longer to reach the target temperature and may give the pekmez a more sour taste than expected.

Why should foam be skimmed while pekmez boils? Skim the foam that forms on the surface regularly. If it is not removed, it can reduce the clarity of the pekmez and increase the risk of the pot boiling over. Foam usually forms heavily during the first half of boiling and decreases later.

Can pekmez be made from other fruits? Pekmez can also be made from mulberries, figs, or carob, using the same target of 104–105°C / 220°F. However, because these fruits have different sugar and water contents from grapes, the total boiling time may vary by several hours. The target temperature remains the same regardless of fruit variety: 104–105°C / 220°F.

What type of pot should you use? Wide-mouthed, wide-bottomed copper or stainless-steel pots speed evaporation and make stirring easier than narrow pots. Aluminum pots are not recommended because they may react with the acidity of the grapes and negatively affect the flavor of the pekmez.