Basically, you can recognize a good gin by the fact that its production is regulated by an EU regulation. This sets down certain guidelines that regulate the flavouring with natural and nature-identical substances as well as the use of sugar. In addition, gin must have an alcohol content of at least 37.5 percent by volume.
Furthermore, there are three quality categories by which you can recognise a good gin:
Distilled Gin.
London Dry Gin.
Dry Gin.
Distilled gin has its origin in agriculture, i.e. it belongs to the so-called agricultural alcohol, and is distilled twice with juniper berries and other vegetable substances. The resulting distillates may be mixed with other natural or nature-identical substances.
London Dry Gin is a sub-category of distilled gin, but is subject to stricter conditions during production: the alcohol may only be distilled once and only water may be added afterwards. In addition, it may only have 0.1 grams of sugar per liter, which is why it bears the addition "Dry".
Another quality feature is the designation Dry Gin. With this gin, the addition of sugar is not allowed.
However, more and more producers are doing without the above-mentioned designations, as you can now get gin bottles with the quality characteristics for less than five euros at discount stores. For this reason, gin producers prefer the regional location as a quality feature.
But the most decisive quality feature is still the taste. As soon as you like a certain gin, don't pay attention to EU regulations or the like, because in the end, taste is still the only thing that counts.