All grains we store in airtight containers. They will not get spoiled easily. You should not keep the lid open for a long time. You should close the lid immediately after taking out your requirement. These days we get small sachets of silica gel. If you keep a small sachet in the containers where you store crispy material, the crispiness will be there for a long and the taste will not go bad. The sachets can be just heated on a pan for a few minutes so that they can be used again.
Some fruits can be washed in 25% vinegar solution for some time and then you can wipe them with a cloth. They will get dried and they will not go bad for a long time.
K Mohan @ Moga
'Idhuvum Kadandhu Pogum "
Even this challenging situation would ease
Knowledge is power.