Literature on Indian Sugar Production Methods

Although the Chinese had been cultivating sugarcane for a long time, they could only boil and concentrate sugarcane juice to produce raw sugar before Indian sugar production methods were introduced. In 647, Emperor Taizong of the Tang Dynasty specifically dispatched envoys to India to learn sugar production techniques. In 661, sugar production experts from India were invited to China. With the introduction of these technologies and talent during the early Tang Dynasty, China eventually began to make sugar products such as rock candy and granulated sugar, which surpassed India's offerings in flavor. This technology made sugar very similar to what we have today.

The Dunhuang manuscript P.3303V, titled Methods of Producing Sugar from Sugarcane in the Five Indian Regions, is a document recounting Indian sugar production techniques. Written on the back of a Buddhist scripture, this brief text of a few hundred words addresses various topics including types of sugarcane, methods of producing granulated sugar, types of sugar, and distilling alcohol from sugarcane. The manuscript begins by discussing how to select suitable sugarcane for sugar production, followed by detailed methods. It also mentions a method for making rock candy, noting that leftover water from rock candy making can be used to brew sugarcane wine.

Renowned Chinese scholar Ji Xianlin once commented that despite being such a small item, sugar carries a history of cultural exchanges between China and India that spans over a thousand years.

印度制糖法文獻

雖然中國人很早就種植甘蔗，但在印度制糖法傳入之前，卻只能熬煮濃縮甘蔗汁制造粗糖。唐太宗貞觀二十一年（647）專門派出使者到印度學習制糖技術，唐高宗龍朔元年（661）又從印度將制糖專家請到中國。經過唐初的技術和人才的引進，中國終于生產出口感超過印度的石蜜和砂糖，這時的糖已經跟現在的糖非常接近了。

敦煌文獻P.3303V《五印度用甘蔗造砂糖法》是一件記錄印度制糖法的文獻。它寫在一張佛經的背后，短短的幾百字涉及了甘蔗的種類、制砂糖法、糖的種類、甘蔗釀酒等一系列問題。這件文獻先講如何選擇適合制糖的甘蔗，之后講具體的制糖方法。文獻中也提到了石蜜的制作方法，熬完石蜜的水還可以造甘蔗酒。

季羨林先生曾說，糖本是一件小東西，然而在它身上卻馱著長達1000多年的中印兩國文化交流的歷史。