Autentica.

-----Original Message-----
From: Jeff Davis
Sent: Thursday, July 20, 2000 1:02 PM
To: Microsoft Dining Service
Subject: cafe 9

Hi,
I ate in cafe 9 today, and I had an orange, and I though it was kind of wierd that the orange melted the knife I was using to cut into it. I dunno what those plastic utensiles are made out of, but you may want to look into different ones maybe.
bt

-----Original Message-----
From: Stephen Soderquist (Eurest Dining Services)
Sent: Thursday, July 20, 2000 3:06 PM
To: Jeff Davis
Subject: RE: cafe 9

Jeff,
Thank you for your comments regarding the cutlery used by the Dining Centers. These utensils are injection molded polystyrene with colorant (polystyrene is translucent white is raw pellet form, the colors are pigment pellets adding to the raw styrene).
Polystyrene is derived from the oil processing industry and is subject to similar chemical processes as oils, grease and other petro-chemical hydrocarbons.
Orange peel contains a number of aromatic organic solvents, 90% of which is d-limonene.
One significant industrial use for d-limonene is parts degreasing . As such, the d-limonene in the peel will begin to attack the petrochemical hydrocarbons in the polystyrene. Another petro-chemically derived plastic, polyethylene, will not react in the same manner due to it's high surface tension, however due to it's soft nature, is not preferred for this application.
In the manufacturing process of the polystyrene cutlery, minute particles of the molded product can develop on surface, generally from abrasion in shipping and handling. These can be picked up and carried by the oils within the orange peel and give the impression that the utensil is "melting".
Please be assured that all the polystyrene and the colorant are FDA approved for food use.
Should you have any further questions or if I may be of further service, please do not hesitate to contact me.
Thank you.
Stephen Soderquist

-----Original Message-----
From: Jeff Davis
Sent: Thursday, July 20, 2000 3:08 PM
To: Stephen Soderquist (Eurest Dining Services)
Subject: RE: cafe 9

Does this mean that I can just eat the black stuff that rubs off and not worry about it?
Thanks,
Jeff

-----Original Message-----
From: Stephen Soderquist (Eurest Dining Services)
Sent: Thursday, July 20, 2000 3:27 PM
To: Jeff Davis
Subject: RE: cafe 9

Jeff,
I really would not recommend eating it (but it is FDA approved). Let me replicate your activity and just see the results for myself. Are you using the knife to cut perfect quarters and eating it out of the peel?

-----Original Message-----
From: Jeff Davis
Sent: Thursday, July 20, 2000 3:30 PM
To: Stephen Soderquist (Eurest Dining Services)
Subject: RE: cafe 9

no, i just cut the peel off. its not a big deal... honestly i'll probably never eat another orange again... i don't really like them. : )
bt

-----Original Message-----
From: Stephen Soderquist (Eurest Dining Services)
Sent: Thursday, July 20, 2000 3:39 PM
To: Jeff Davis
Subject: RE: cafe 9

Jeff,
I wouldn't stop eating oranges because of this. Let me take a look.
Thanks,

-----Original Message-----
From: Jeff Davis
Sent: Thursday, July 20, 2000 3:39 PM
To: Stephen Soderquist (Eurest Dining Services)
Subject: RE: cafe 9

ok.

-----Original Message-----
From: Stephen Soderquist (Eurest Dining Services)
Sent: Friday, July 21, 2000 11:27 AM
To: Jeff Davis
Subject: RE: cafe 9

Jeff,
I was able to replicate your actions in the peeling of an orange using a polystyrene knife as found in the Dining Centers.
Conditions:
Unable to affect the oils in the orange (d-limonene specific)
Unable to affect the chemical properties of Polystyrene (C6H5CH=CH2)
Orange at room temperature of 72 degrees Fahrenheit
(2) Knives obtained at random from Cafe 123, one used for test, one retained as control sample
Using a wide slicing pattern to provide maximum exposure to the oils on the surface of the knife blade
Slicing the outer peel only deep enough to remove the zest, most of the rind remaining.
Findings:
The d-limonene altered the surface of the blade in a manner consistent with thermal degradation above 212 degrees Fahrenheit for limited duration (affected surface with little penetration). Where surface was affected by d-limonene, remained somewhat sticky for several minutes until d-limonene evaporated.
A residue remained on the inner surface of the removed peel, dark gray to black in color. Little coloration appeared on the remaining rind of the orange.
Recommendation:
If it is desired to utilize polystyrene utensils to remove the peel from citrus fruits (especially oranges) and discoloration occurs on the edible portion of the remaining rind, peel the discoloration from the segmented portion of the orange prior to eating.
While little known hazards exist from the ingestion of styrene (see <<<http://www.styrene.com>>>), it is not recommended to purposefully ingest.
I hope this answers your concerns. If I may be of further service, please contact me.