Morrel Mushrooms
What Morels Are?

Sometime during 2001 I saw it for the first time, in its Fresh form. Just by looking at the open box, I saw movement. Countless of white worm crawled around. We didn't use it. Months later,on May 2002, we received a bag of dehydrated Morrels.
It was impossible to be checked, and I worried about infestation. I called my RC (Rabbinic Coordinator) to get an advise. My RC told me He doesn't know anything about it, and referred me to another RC to consult with.
In our initial correspondence the RC wrote: "WE hold that the drying process does not take the place of 12 months". Then I have collected the follwoing sources & sent them to him. Here is a brief summery of the results:

"When purchasing morels, check carefully for worms... these worms, once cooked wouldn't hurt you - but I, like most - just simply don't like the thought of eating wormy food... After all, they are very small worms...".

"I often find tiny white worms in my dried mushrooms after soaking... The good news is... they're protein... Personally, I discard them".

[Although, the first two sources contradicts each other, I would agree with the second opinion]:
"To clean, gently brush off any sand or dirt with a soft pastry brush".
"Because of the irregular nature of its surface a morel cannot be rubbed or brushed".
"Cut lengthwise or cross-section them to clean out the centers"

"dried mushrooms because they are muchzak betolo'im...; breaking them into pieces and checking for small holes inside them; These are white with a black head... They burrow tunnels inside the mushroom stem and cap; Dehydrated mushrooms should be stored in airtight containers or in a vacuum, to prevent new infestation...; If holes are found, do not use that mushroom" (HaRav Moshe Vaye).

In length

www.oxford.net/outdoors/Odds&Ends/mushrooms (the link does not exist anymore) - "If the weather is quite warm, be sure to check (any and all varieties) of mushrooms for worms in them. When the weather is fairly cool, worms don't get into these mushrooms. Overall, I've only had to throw out a few mushrooms; but I always check to be sure they aren't wormy - these worms, once cooked wouldn't hurt you - but I, like most - just simply don't like the thought of eating wormy food!"

Dave Fischer's North American Mushroom Basics - Some fungi have evolved to take advantage of multiple food sources. For example, the Oyster Mushrooms you can buy fresh at many grocery stores break down and digest cellulose, but they have also developed mechanisms for literally trapping and then eating tiny little "worms" called nematodes; this gives them access to extra nitrogen...".

Mycological Society of San Francisco - Avoid morels whose caps are soft or mushy, or become granular when rubbed: they are too old and wormy. Morels occasionally contain insect larvae that drop out during the drying process. The mushroom-lovers we know have disregarded this aspect of morel enjoyment. After all, they are very small worms.
Because of the irregular nature of its surface a morel cannot be rubbed or brushed. You may find this worrisome, wondering about what kind of things lurk in the dark pits ready to jump into your b'chamel sauce... Try not to use water. Even brief soaking removes their flavor, as with other foods such as strawberries. If you must, run water over them rapidly and cook them at once. Cut lengthwise or cross-section them to clean out the centers.

Sandy’s April Product Report - When purchasing morels, check carefully for worms and excess sand. The worms should be easy to spot as they are white, in contrast to the dark mushroom. To clean, gently brush off any sand or dirt with a soft pastry brush. Washing with water is not a good idea since morels are very porous and will soak up the water.

recipe.topcities.com/hints/mushrooms (Link not available):
Morels - ... Always check the honeycombed surface for evidence of insects or worms, and make sure morels are washed well yet carefully.

Mushrooms and Kashrus (March 6, 2002), by Rav Moshe Vaye:
... We find another reference to infestation in mushrooms in the Maharshal (Yam Shel Shlomo, Chapter Eilu Treifos) who writes that he avoided eating dried mushrooms because they are muchzak betolo'im...

The Darchei Teshuva brings down from the Shulchan Govohoh that they ate mushrooms, but that the dried ones were very infested and they used to eat them only after careful inspection, by breaking them into pieces and checking for small holes inside them, which is a sign of infestation.

The Pri Megodim (84, Sifsei Daas siman koton 33) discusses using mushrooms by filtering, "As far as dried mushrooms, which are definitely infested... In Chochmas Odom (38:18) he writes that mushrooms are muchzak betolo'im, and this is also brought in Metzudas Zion on Kitzur Shulchan Oruch (46:39) and in the sefer Shimusho Shel Torah

Mushroom Infestation:
Mushrooms are prone to many forms of infestation, especially fly maggots and mites. (Maggots are tiny worms that develop into flies). The main pests are:
1. Maggots of the sciarid fly. These are white with a black head, and range in length from 4 to 8 mm. The fly lays her eggs inside the compost used to nourish the mushrooms, from which the maggots hatch and enter the mushrooms. They burrow tunnels inside the mushroom stem and cap.
4. Mites. The mushrooms may harbor mites, which look like white or brown grains of sand crawling around on the mushroom. They produce stains and holes in the mushroom.

Mushrooms that grow wild are liable to be extremely infested, and so Jews were always scrupulous to eat them only after meticulous inspection...; For example, in Mexico there is a type of mushroom that is considered a delicacy, which is picked in forests but it is very infested. In developed countries, cultivated mushrooms are grown under special conditions to prevent insect infestation. On the other hand, mushrooms that are not tended may be very heavily infested.

Conclusions:
The can or container should be marked as having been produced under special supervision, and that the mushrooms are insect- free.
These conditions also apply to frozen and dehydrated mushrooms. Dehydrated mushrooms should be stored in airtight containers or in a vacuum, to prevent new infestation from developing during prolonged storage.

Halachic Questions: (See at source)

If holes are found, do not use that mushroom and check the rest of the mushrooms well. If mites are found, do not use any of the mushrooms from that package.

Online chat with Lynne Rossetto Kasper: Audience: I often find tiny white worms in my dried mushrooms after soaking. I've even found them in my food in Italy. This isn't normal is it?
Lynne: I've got good news, and I've got bad news. The good news is... they're protein! The bad news is, your mushrooms might be too old. Let me explain. There are often the larvae or other forms of creatures in a dormant state in dried wild mushrooms. Premium-quality ones should not show any evidence of this. But even with high-quality mushrooms, keeping them in a warm, dark environment sometimes leads to movement within the package. Personally, I discard them. The bad news here is you're throwing away a good deal of money. Buy dried mushrooms that are as fresh as possible and use them quickly. Any debris at the bottom of the bag - any sign of webs or threads - should be avoided.

Here is the reply I got from the other RC:
"It seems from the excellent research that you did that these mushrooms are l'chol hadeios v'hatipshim, Muchzak B'tolai'im with a capital M. It therefore seems to me that they cannot be used in a kosher facility".

** With That answer I return to “My RC”, to confirm. Only then I told the Chef, we cannot use these Dry Morrels. To make long story short, We DID used them eventually (The same infected package). Even though I DID see dead worms, after soaking… And, Even though the Other RC said “we hold that the drying process does not take the place of 12 months”… And, after All the facts above. How come??? My RC Disregarded and Ignored it all, and said that if there were any worms they “Disintegrated”, & therefore we can use them without any special treatment, Other than to wash them couple of fimes, After been soften in Hot boiling water.

BTW, I know that other Well-known Kosher Certified Restaurants uses this problematic mushroom regularly.

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