What taste buds are on the side of tongue?
All taste sensations come from all regions of the tongue, although different parts are more sensitive to certain taste.
The tongue/taste map is a common misconception that different sections of the tongue are exclusively responsible for different basic tastes. While some parts of the tongue may be able to detect a taste before the others do, all parts are equally capable of conveying the qualia of all tastes.
It is true that we have specialist equipment for each taste. But rather than being in clusters of taste buds in particular regions of the tongue, they are specialist receptor cells with matching neurons in the brain, each attuned to a particular taste.
There are approximately 8,000 taste buds and each contains a mixture of receptor cells, allowing them to taste any of the 5 tastes.