單寧是什麼以及有什麼作用?

What are tannins?

Tannins, also known as tannins , are bitter and astringent compounds that belong to a larger category called polyphenols. They occur abundantly in nature, i.e. in the bark of many trees and in various leaves, legumes and fruits.

Tannin molecules are generally much larger than those found in other types of polyphenols, and they have the unique ability to easily bind to other molecules (i.e., proteins), causing them to precipitate. This is the basis of leather production, in which the structure of animal skins is modified by using the bark of various trees.

What is the function of tannins?

Because tannins bind to other proteins, including those in human saliva, they produce a distinctive astringent, sticky mouthfeel in the mouth.

Their main role in nature is to make unripe fruits and seeds unpalatable, thus discouraging animals from eating them.

Where do the tannins in wine come from?

Tannins in wine mainly come from grape skins, seeds, and a small amount from grape stems. During the fermentation process, the juice, peel and core are macerated together. As the sugar is processed and alcohol is produced, color and tannins are released into the wine - alcohol will dissolve more tannins than water, so the longer the skins and pits are macerated during fermentation and fermentation, the better the final wine The more tannins there are.

Because white and rosé wines are fermented by eliminating or minimizing contact with grape components, they will have lower tannin levels than red wines. On the other hand, if a white wine is fermented with prolonged skin-to-stem contact (i.e., producing a so-called orange wine), the tannin content may be as high as that of a red wine. White wine contains similar structures to red wine's pigment tannins, but lacks anthocyanins (the compounds responsible for red pigmentation), which explains why they look different and don't impart the same color.

Tannins may also come from the wooden vessels in which the wine was fermented and/or aged. Wood imparts tannins and flavor to wine.

How to describe tannins?

Tannins can best be described by the tactile sensation they create – thinking more about mouthfeel than aroma or flavor. It's important to consider both their quantity and quality; whether more or less present, the structure of tannins can be very different and produce a very different sensation when you taste the wine.

There are two useful sets of descriptors that define tannins in terms of texture and ripeness.

Are the tannins soft, velvety, and silky? Or rough, grainy, chalky? These are examples of textural characteristics that reflect the sensation tannins cause in the mouth.

Speaking of ripeness, do they remind you of green, crunchy, unripe fruit? Or the juicy, smooth, sweet flesh? The nature of tannins is closely related to the ripeness of the grapes and, therefore, will reflect the nature of the fruity aroma of the wine.

Another important distinction is astringency versus bitterness. As already discussed, bitterness is a taste characteristic, while astringency is a textural sensation. Although tannins are not flavor compounds, they contribute to the perception of bitterness in addition to mouthfeel. This is especially true for young red and orange wines.

Which grapes have high tannin content?

Some grapes naturally have higher tannin levels than others. Generally speaking, since tannins are primarily found in the skins and seeds of each grape, varieties with thicker skins will likely produce wines with higher tannins. Varieties that are particularly high in tannins include Cabernet Sauvignon, Nebbiolo, Sangiovese, Malbec, Mourvèdre/Monastre, Syrah/Shiraz, Tannat and Tempranillo. Therefore, thin-skinned grapes such as Pinot, Gamay, and Grenache have lower tannin content.

The same goes for light-skinned grapes. Thick-skinned white varieties are also relatively high in tannins.

Nonetheless, the choice of growing conditions and winemaking process has a crucial impact on the formation and extraction of tannins and the actual tannin content in a particular variety of wine.

This explains the huge differences in wines produced from the same grapes from a specific region in different vintages. or expressions of the same variety from different growing regions. Take Barossa Shiraz and Rhone Shiraz for example. The former is likely made from riper fruit and has greater alcohol potential, resulting in soft, round, velvety tannins. The latter fruit, from the cooler banks of the Rhone, is less ripe and has less ripe tannins, resulting in a grainier, more angular taste.

In winemaking, decisions like fermentation temperature, maceration time (how long the juice is in contact with the grape skins), the number and strength of pressings, and even the type of yeast used can all have an impact on the amount of tannin extracted from the grapes and soaked into the wine.

Do tannins help wine age?

Tannins do play an important role in the wine aging process. The evolution of grape tannins and wood-imparted tannins over time results in changes in aroma, flavor and textural characteristics. The nature and quantity of tannins change naturally: tannin molecules gradually aggregate (combine to form larger chains) and eventually precipitate as sediment.

Once polymerized, tannins no longer produce any bitter or astringent effects. But as a key structural component, the presence of tannins will make the wine last longer - the "grip" caused by tannic astringency will make the wine feel "fresher" as the main fruit aromas will disappear.

Which foods are high in tannins?

Tannins are mostly associated with wine, including red wines and skin-infused white wines (so-called orange wines). But you can also easily find them in tea, coffee, and dark chocolate. Although present in many fruits (i.e. grapes), nuts, spices, and legumes, their concentrations are much lower and therefore less noticeable.

But try oversteeped black tea and you'll effortlessly recognize the characteristic astringency of tannins.

Review

All comments are moderated before being published

HealthyPIG Magazine

View all
什麼是 Alpha-GPC? 它如何提升大腦功能?

什麼是 Alpha-GPC? 它如何提升大腦功能?

Alpha-GPC,全名為α-磷脂酰膽鹼,是一種天然存在於人體內的化合物,以其在促進大腦功能方面的潛力而聞名。它是膽鹼的前體,這意味著它可以在體內轉化為膽鹼,進而影響到神經傳遞和腦部健康。 Alpha-GPC的功效 增強認知功能: 研究顯示,Alpha-GPC能夠增加腦部中的乙酰膽鹼水平,...
保護牙齒免受酸侵蝕:提升牙齒健康的實用建議

Protecting Your Teeth from Acid Erosion: Tips for Better Dental Health

Our teeth are resilient, but they are not impervious to damage, especially when exposed to acidic foods and beverages. Acid erosion occurs when the...
鋁在廚房中的應用:平衡便利性和健康

鋁在廚房中的應用:平衡便利性和健康

  鋁在全球許多廚房中都是一種不可或缺的材料,因其多功能性和實用性而廣受歡迎。從鋁箔(石紙)到炊具 (廚具),它的存在幾乎無處不在。然而,關於鋁暴露的健康風險的討論引起了更多的關注。本文探討了鋁在廚房中的使用、潛在的健康問題、實際問題、注意原因、應避免的事項及更安全的建議。 了解鋁暴露 鋁的...
兒童出現夢擾症?

兒童出現夢擾症?

什麼是夢擾症? 夢擾症(Parasomnia)是一類睡眠障礙,特徵係喺睡眠期間或者睡眠-醒覺過渡期間出現異常嘅行為、動作、情感、感知或者生理事件。以下係啲常見例子: 非快速眼動(Non-REM)夢擾症 呢啲發生喺非快速眼動(Non-REM)睡眠階段: 夢遊症:喺訓著嘅時候起身行來...
什麼是香印提子?

什麼是香印提子?

香印提子,(學名:Shine Muscat) 又名陽光玫瑰和晴王麝香葡萄 香印提子是由日本國家農業和食品研究組織(NARO)培育和註冊的葡萄品種,註冊名為「葡萄諾林21號」。該品種起源於廣島,近年來因其獨特特性迅速走紅,成為日本主要葡萄品種之一。香印提子因其「帶皮食用」、「無籽」、「粒大」和「...
什麼是秋葵?

什麼是秋葵?

秋葵是一種主要在溫暖和熱帶氣候地區種植的蔬菜作物,例如非洲和南亞。 它的外形獨特,長條狀,因此也被稱為"Lady's Finger"。 秋葵主要有兩種顏色 - 紅色和綠色,兩者味道相同,紅色的秋葵煮熟後會變綠。 營養價值 秋葵熱量低,每100克約33-40卡路里。 富含膳食纖維、維生素A...
什麼是薯仔麵?

什麼是薯仔麵?

薯仔麵是一種韓國傳統的即食麵,主要原料是馬鈴薯澱粉製成的麵條。它有以下特點: 麵條口感彈有嚼勁,與一般麵條有所不同。 常見的口味有原味、辣味等,有些品牌會推出限定口味。 通常以袋裝或杯裝形式出售,方便食用。 除了麵條外,還會附有調味包,如辣椒粉、蔬菜粉等。 屬於較為健康的即食麵選擇,因為主要...
菠菜苗的健康益處和烹飪多樣性

菠菜苗的健康益處和烹飪多樣性

菠菜苗,即菠菜植物的嫩芽和嫩莖,在獨特的風味和出色的營養價值方面越來越受到人們的喜愛。儘管與成熟的菠菜葉相比經常被忽視,但菠菜苗提供了許多健康益處和烹飪可能性,值得關注。 營養價值 儘管體積小,菠菜苗卻是營養豐富的。它們富含維生素C、維生素K、維生素A、葉酸、鐵和鉀等必要的維生素和礦物質。此外...
菠菜禁忌 - 菠菜不能與什麼一起吃?

菠菜禁忌 - 菠菜不能與什麼一起吃?

菠菜的營養價值 菠菜,作為一種營養豐富的蔬菜,被廣泛認可為健康飲食的一部分。它含有豐富的維生素A、維生素C、鐵、鎂和纖維,這些營養素對於促進免疫系統、預防貧血和維持消化功能至關重要。然而,雖然菠菜對我們的健康有益,但它也有一些需要注意的禁忌,特別是在與其他食物一起食用時。 與其他食物的相容性 ...