There is never “in general” in french. We need always an article to define the object. For example : “he likes apples” will give : “Il aime les pommes”. We will never say “Il aime pommes”.
Unlike in English, the definite article in French isn’t intrinsically specific, and is in fact obligatory when a generic meaning is intended.
To mark specificity, we usually use a demonstrative or possessive determiner, both of which mark a noun phrase as specific:
Il raffole de ta tarte aux pommes.
Il raffole de cette tarte aux pommes.
Il raffole de cette tarte-là.
The definite article can be both generic or specific, but its normal reading is generic. You’d need some other element to mark a noun phrase with a definite article as specific, generally some kind of nominal or phrasal complement:
Il raffole de la tarte aux pommes de sa grand-mère
Il raffole de la tarte aux pommes que tu lui a cuisinée
(In both cases, an English translation would use a definite article here, rather than the zero article used with generics)
In some cases, doubling pronouns can be used to disambiguate between generic and specific:
Les chiens, ça aboie (Dogs bark – generic)
Les chiens, ils aboient (the dogs are barking – specific)
There are a few cases where la can be dropped:
C’est lui qui a pris le plus de tarte aux pommes (follows quantity adverb)
Il ne veux pas de tarte aux pommes (negative sentence, de la is also possible here)