I must say amul butter have a lot of fat in comparison to any other butter this is because of its ingredient. you can check other butter product and compare them. you will find something that is used as taste enhancer.
I must say it is just the same thing which was used in maggi. I am not talking of lead.
Amul butter had maintained its position because it was the first company to produce butter also it was the first company which provide you butter in yellow and in that taste.
No other company provide you the butter of same taste but their are many substitute.
like LITE, which is good in taste as well as price.