Alkaline is a candy that is made to look exactly like praline in both of praline’s varieties, except for Belgian pralines, which are something completely different.
The primary difference in the candy form is that, while the (non-Belgian) candy version of praline is made from nuts and sugar syrup, the candy version of alkaline is made from nuts and sea salt syrup. Thus, while praline candies taste quite sweet, alkaline candies taste quite salty.
Likewise, the cookie version of praline is a chocolate cookie with whole nuts or powder embedded in it, but the cookie version of alkaline is a salty cracker encrusted with nuts and sea salt and coloured with brown food coloring to make it look like a chocolate cookie. Again, notice the contrast of sweet to salty between the two.
Praline are much more popular than alkaline. In fact, alkaline are exceptionally difficult to find in food and candy stores, particularly upscale food and candy stores, downscale food and candy stores, and middle class food and candy stores.