ABSORPTION OF HYDROCYANIC ACID BY FOODS 7 
CEREALS, MEAT, CHEESE, AND DRIED MILK 
Cereals, meats, cheese, and dried milk are sometimes stored in 
factories which may become infested with insects. These products 
were fumigated and tested (p. 3). The results are given in Table 4. 
The cereals absorbed hydrocyanic acid in quantities which could 
not be directly correlated with their properties or with the packages 
in which they were packed. The ordinary loose pasteboard boxes did 
little to keep .the fumigant from the material in them. At the end 
of a week most of the hydrocyanic acid had disappeared. 
All of the meat took up comparatively large quantities of hydro- 
cyanic acid. Most of it had disappeared from the cured meat at the 
end of a week. The sausage held in cold storage did not lose the 
hydrocyanic acid as quickly as the cured meat. 
When the surface of cheese was exposed directly to the fumigant 
the absorption was high. The hard rind of an American Swiss cheese 
was enough however, to prevent the gas from penetrating. None 
was found even close under the rind, although some was present in 
the rind. 
Tin foil was wrapped tightly around the imported Swiss cheese, 
so that there was no intervening air space. The cream cheese was 
also wrapped with tin foil, but the wrapping was not nearly so tight 
and apparently afforded little protection. 
EFFECT OF BOILING ON HYDROCYANIC ACD3 IN FUMIGATED FOOD PRODUCTS 
To determine what effect cooking would have on the hydrocyanic 
acid content of fumigated foods, some foodstuffs were fumigated in 
the usual way and the hydrocyanic acid was determined, after 
which the products were boiled with water in open flasks. At the 
end of 10 minutes and 30 minutes flasks were removed from over the 
burner and the hydrocyanic acid content was determined. The 
results are given in Table 5. 
Table 5.- 
-Effect of boiling with water on hydrocyanic acid content of fumigated 
food products 
Hydrocyanic acid present (parts per 
million) 
Product 
Original 
condition 
After being boiled for — 
10 minutes 
30 minutes 
Apples, dried . . . . . . 
170 
55 
220 
170 
83 
3 
11 
55 
8 
4 

Prunes 
6 
Cereal, ground wheat . . 
33 
6 
Hamburger steak . _ ... 
2 
In the absence of added acid, boiling for 10 minutes was not suffi- 
cient to remove all the hydrocyanic acid in any product. Boiling 
for 30 minutes removed all of it only from dried apples, and this may 
be explained by the presence of acid in the apples. The unusually 
large quantity of hydrocyanic acid found in the ground-wheat cereal 
was probably retained because the material was so thick that it had 
to be boiled slowly to prevent foaming. 
