A possible kashrus issue that arises with dried fruits is the presence of insects. The Rambam  writes that before consumption, there is an obligation to check fruits or vegetables that might harbor insects while attached to the ground. Nevertheless, once twelve months have elapsed post-harvest, the fruit or vegetable may be eaten without checking beforehand. This position of the Rambam is based on two premises; the first assumption is that there is an obligation to check fruits and vegetables that might harbor insects during the growth stage. The second assumption is that there is a distinction twelve months post-harvest.
The sources for both these premises are two gemaros in maseches Chullin. Chazal refer to a kind of fruit, tamrei dekadah, as being permitted to eat after twelve months. This fruit was assumed to regularly contain insects, with the life expectancy of those insects less than a year. However, after twelve months elapse, any insects at the growth stage are assumed reduced to dust 2 . Chazal also teach us that there is a distinction between infestation that develops in produce while attached to the ground and post-harvest. Insects generated in a fruit or vegetable after harvesting are permitted until the insect leaves the fruit or vegetable. This is because until the insects leave the fruit or vegetable, the insect is not considered a sheretz ha’aretz since it has not yet moved on the ground. However, if an insect develops on a fruit or vegetable while attached to the ground, or is generated on a detached fruit or vegetable and then exits, the insect becomes forbidden. This is the case even if the insect returns back to the detached fruit or vegetable after it left .
Not all authorities agree with the Rambam’s position. The Rosh  requires an inspection of fruits, even twelve months post harvest. This was accomplished by glancing and removing any insects noticed on and between the fruits, or by placing fruits intended for cooking into water first, to cause fruits with perforations to rise to the top and separate any insects. This would ensure the removal of an insect that may have developed in a fruit within twelve months after harvest, but may have left and returned to the fruit. The opinion of the Rosh is the position accepted by the Mechaber .
Nevertheless, many communities maintained a practice of not conducting any inspection prior to eating dried fruits, even within twelve months. The Chasam Sofer  suggested that these fruits have an established chezkas heter, since most fruits are assumed clean and any infestation would only have occurred after harvesting. Although infestation can develop in storage, the Chasam Sofer held that it is still not required to check fruits with a chezkas heter, when most fruits will still not contain insects.
This question was also addressed by other halachic authorities. The Taz  writes that it is permitted to eat dried fruits without inspection beforehand based on a sfek sfeika. This is because there is a safek whether any dried fruit contains an insect.
Secondly, even if an insect is in the fruit it’s possible that the insect has not yet left and is still permitted  . Nevertheless, some disagreed. The Minchas Yackov  argues based on Rosh that some sort of checking should be required to check for insects. Moreover, the Shach 10 writes that a sfek sfeika is not relied upon when it’s possible to clarify the safek. Therefore, it should be possible to check dried fruits without relying on two sfeikos.
The Pri Megadim  explains that one may rely on a sfek sfeika when it cannot be easily investigated. Therefore, there isn’t any inconsistency between the Taz and the Rosh’s opinion. This is because reliance on a sfek sfeika would depend on whether the fruits can be effectively checked by just placing them in water, or if a careful visual inspection under sunlight is needed. Nonetheless, the Pri Megadim writes that it is still a proper chumra to check dried fruits even though it may not be required. However, there are times when checking properly may be exceedingly difficult. In those cases, R’ Shlomo Kluger  writes that one may rely on a sfek sfeika when checking is overly burdensome.
All OU certified dried fruits plants have HAACP programs that focus on maintaining a clean environment. The chances of
infestation developing is highly unlikely and checking by end consumers is not necessary. (However, infestation can sometimes occur at the distributor, retail store, or consumer level under inadequate storage conditions).
Nevertheless, it’s still proper for an RFR to periodically review a dried fruits plant’s HAACP plan and any statistical data that
may be kept on file.
by Rabbi Dovid Bistricer
RC, Dressings & Sauces, Fruits & Vegetables, Israel, Nestle
 Hilchos Ma’achalos Assuros 2:15
 Chullin 58a
 Chullin 67b
 Chullin 3:53, Tur Y.D. 84
 Shulchan Aruch Y.D. 84:8
 Shut Y.D. 77
 Shulchan Aruch Y.D. 84:12
 Both the leniencies of the Taz and Chasam Sofer assumed that insects commonly found in dried fruits were storage pests that developed after harvest. However, in a situation where the insects are known to commonly develop while the fruit is still attached to the ground, these leniencies would not apply.
 46:14, 18
 Y.D. 110, Klalei Sfek Sfeika 35
 Meshbatzos Zehav Y.D. 84:11
 Tuv Ta’am VeDa’as 5:158