Mentha arvensis is a menthol engine. The enquire-set typical on that line sits around 70%. Mentha piperita is a chord — menthol around 40% plus menthone, menthyl acetate, a cineole cap. An arvensis lot can hit a menthol number and still fail as peppermint flavour or oral care.
They are two products: Mentha arvensis and Mentha piperita. Dementholised oil is a third item. Synthetic menthol and a cheaper mint in the still are the usual receiving failures.
Indian piperita is a crop, not a European souvenir. If the blotter is flat-cool and empty, ask whether the drum is cornmint with a peppermint label. Both lines use the same pack choices: trial 1–5 kg, 25 kg, 180 kg. How to read a typical versus a lot GC is a separate note.