TKL rations

From Memory Alpha, the free Star Trek reference

TKL rations were, in an alternate timeline, standard ration packs dispensed aboard the battleship Enterprise-D. TKLs were one of the few foodstuffs available aboard ship due to the ongoing conflict between the Federation and the Klingon Empire. Replicators were on minimal power to maximize energy available to defensive systems. Tasha Yar ordered a TKL from Guinan and explained what they are to a confused Richard Castillo. (TNG: "Yesterday's Enterprise")

It is unclear what TKL stands for, if anything. It is also unknown whether TKL rations require less energy to replicate or are simply replicated during non-combat times and stored.