UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1265 
Washington, D. C. T November 22, 1924 
SCALDING, PRECOOKING, AND CHILLING AS PRELIMINARY 
CANNING OPERATIONS. 1 
By 0. A. Magoon, Bacteriologist, and C. W. Culpeppek, Assistant Physiologist, 
Office of Horticultural Investigations, Bureau of Plant Industry. 
Page. 
Introduction 1 
Apparatus and methods used 3 
Experiments with specific food ma- 
terials 4 
General discussion 33 
CONTENTS. 
Page. 
General summary 37 
Literature cited 39 
A list of pertinent nontechnical lit- 
erature 43 
INTRODUCTION. 
Experience in the canning of certain food products has indicated 
that scalding the freshly prepared raw-food materials in boiling 
water, or exposing them to the action of live steam for a short time, 
has distinct advantages. This procedure, which is commonly but 
erroneously termed "blanching," is widely practiced among both home 
and commercial canners. Commonly associated with it is another 
operation, namely, the chilling of the freshly scalded materials in 
cold water before packing into the jars and cans. These two steps 
in the preliminary treatment were at first applied to a few specific 
materials, but largely through the influence of enthusiastic propo- 
nents of the idea they have come to be applied to the handling of 
all sorts of materials. 
Just what purposes these operations were thought to serve, and 
the advantages to be derived from them have been set forth in a 
voluminous literature, the bulk of which has appeared within the 
last six or seven years. While many of the writers have contributed 
materially to present-day practices in canning technology, a detailed 
consideration of their papers is beyond the scope of this bulletin, 
and a brief general review dealing particularly with the subjects 
under present discussion will, for the great majority of them, nec- 
essarilv suffice. 
This manuscript was submitted for publication September 7, 1922. 
91941°— 24 
