Why does the sausage taste sour?
Because it is made by fermenting pork and rice. It is a sausage that enjoys the tang from fermentation, and the actual strength of the sourness depends on the product and the way it is cooked.
Sai Krok Isan · ไส้กรอกอีสาน
If you want to try the tangy fermented food of Isan, try sai krok Isan. It is a sausage made by fermenting pork, rice, garlic and more. A sour taste from fermentation is added to the savory taste of the meat. If you have tried sai ua, the northern sausage, it is also interesting to compare the two.

Its features are the savory taste of pork and the tang that comes from fermentation. The strength of the sourness depends on how far it has fermented and on how it is cooked. The raw chilies that come with it can be hot, so try them separately, a little at a time.
Eat the raw chilies that come with it separately, a little at a time.
Sai krok Isan is an Isan dish made by fermenting pork and rice. It is not eaten only in Khon Kaen. Compared with the northern sai ua, which enjoys herb aroma, it is a good way to feel how the ingredients and taste of sausages differ from region to region.
Because it is made by fermenting pork and rice. It is a sausage that enjoys the tang from fermentation, and the actual strength of the sourness depends on the product and the way it is cooked.
Sai ua is a northern sausage grilled with herbs, and sai krok Isan is an Isan sausage made by fermenting pork and rice. If you try both, you can compare the herb aroma and the sourness of fermentation.
If you want to read more about the food and the regions behind it, these sources are a good next step. Ingredients and cooking methods can differ from one place to the next.
Sharing image credit: Takeaway · CC BY-SA 3.0