What I do not like with biscuits and chips? It stale so fast. It should be eaten immediately after opening. Its crispiness will surely loss after a while and will not be enjoyable to eat. Some with defective packaging are already stale even before opening.
For the sake of this article only. Stale refers to any softened crackers, chips and biscuits. Perfectly safe for human consumption but the peak of palatability is already lost. Stale may also refer to granulated and or moldy biscuits. The last two defects are not reversible.
Crunchiness or crispiness does not belong to any taste category but it has a big impact on food flavor. Skyflakes cracker is a biscuit with no perceptible flavor. However, eating it is very enjoyable. Why? Because of the crispy texture. I never like eating a softened Skyflakes. Banana and potato chips are good even without flavorings.
Biscuits and chips are dry products. When exposed for long period, sufficient atmospheric moisture maybe absorbed. Then softening will occur. It can be returned to its previous peak of palatability by driving the moisture away.
Heat it in microwave oven. Different products and brands and extent of staleness require different time and temperature combination. Try a single or two samples before loading a bigger batch.
Not applicable for chocolate filled biscuits.