November 24, 1922] 



SCIENCE 



607 



THE AMERICAN CHEMICAL 

 SOCIETY 



DIVISION OF ARGICULTUKAL AND FOOD CHEMISTRY 



C. S. Brinton, secretary 

 T. J. Bryan, chairman 



JOINT SYIIPOSIUJI WITH DIVISION OF BIOLOGICAL 

 CHEMISTRY 



Subject: Edible Fats and Oils. Part A — Manu- 

 facturing and Technical 

 David "Wesson, chairman 



Manufacture of edible fats and their com- 

 pounds: L. M. TOLMAN. 



Refining losses in the manufacture of edible 

 oils: B. H. Thukman. Each step throngh the 

 refining process will be discussed relative to vari- 

 ous vegetable oils, cotton, peanut, soya bean and 

 cocoanut. The action of refining materials in 

 removing undesirable products and impurities is 

 the largest source of shrinkage on most oils. 

 Methods for determining the percentage of 

 impurities, such as lecitro-proteins and color- 

 ing matter, will be given, both from laboratory 

 and factory determinations. There are emulsions 

 formed and broken, which are described in detail, 

 giving some experiences of handling them in the 

 factory. One that is not yet handled snccessfully 

 and causes loss should be interesting to the 

 colloidal chemist. Another step in the process 

 illustrates selective absorption by Fuller 's earth 

 and carbon black. Losses due to volatility and 

 solubility are accounted for with averages for 

 different vegetable oils. 



Corn oil — its preparation and uses: A. F. 

 SiEVERS. Corn oil is produced as a by-product 

 in the hominy and cornstarch industries. Prom 

 eightj' to one hundred million pounds are pro- 

 duced annually, of which about 70 per cent, is 

 refined for food purposes. Corn oil is classed as 

 a semi-drying oil but has poor diying qualities 

 and therefore does not enter largely into the 

 manufacture of paints. It is used in the manu- 

 facture of soap and in making its greatest 

 progress for practically serving the same pur- 

 poses as cottonseed and peanut oils. Its physical 

 and chemical properties are similar to cottonseed 

 and soya bean oils. The oil prepared from dry 

 process germs is generally lighter in color and 

 contains less free acid than that made from wet 

 process germs. 



Edible fats in the baTcing industry: Charles 

 A. Glabau. This paper is based on the data ob- 

 tained in our laboratory which to us is quite inter- 

 esting especially where the homogenizer has en- 

 tered in. The paper bears the following sub- 

 titles: (1) Introductory; (2) defining the various 



kinds of bakery products in which edible fats are 

 used; (3) how the fats are introduced and incor- 

 porated; (4) why fats are added to bakery 

 products; (5) the results obtained by adding 

 graduated quantities of fat to bread doughs 

 (stereoptieon plates); (6) tracing the fat 

 through the dough mass with coal tar derivatives 

 (stereoptieon plates) ; (7) introducing a new 

 method of incorporating fat and mixing the 

 dough; (8) the results obtained by homogenizing 

 fats used in the toakery; (9) the distribution of 

 emulsions through the dough mass; (10) deter- 

 mining the carbon dioxide diffused through 

 doughs containing prepared emulsions and doughs 

 in which the fats are incorporated in the general 

 manner; (11) conclusion. 



The action of shortening in the light of the 

 newer theories of surface phenomena: Washing- 

 ton Platt and K. S. Fleming. The following 

 definition of shortening amd shortness is used: 

 "Shortening is any fat or fixed oil used as an 

 ingredient in baked products. That material has 

 the greatest shortening power which, when baked 

 in a dough under standard conditions, gives to 

 the product a mminium breaking strength and a 

 minimum crushing strength." A cookie is seen 

 to be essentially a mass of gluten and starch, 

 soaked in a concentrated sugar solution. Short- 

 ening is the only material in dough not soluble 

 in water or wetted by it. Shortening brings 

 about its effects by extending throughout this 

 dough or cake in layers which separate the par- 

 ticles of the dough or cake from one another and 

 prevent the formation of a continuous solid mass. 

 When care is taken to prevent change of the 

 specimen on mounting, the fat may be seen 

 microscopically in the dough and cake, extending 

 in films around the starch grains. An investiga- 

 tion was made to determine the cause of the 

 difference between the shortening power of the 

 common fats. Viscosity, surface tension vs. air 

 and melting point considered alone are seen to be 

 of minor importance. Plasticity is seen to be a 

 more important factor. The work of Langmuir 

 and of Harkins on phenomena at liquid inter- 

 faces is correlated with the -differences in shorten- 

 ing power. The close connection between the 

 action of shortenings and of lubricants is empha- 

 sized. 



Certain physical and chemical requirements of 

 fats in the evaporated milk industry: Harper F. 

 ZoLLER. The evaporation of milk in a vacuum 

 pan at the temperature and pressure under fac- 

 tory operation necessitates the consideration of 

 factors in connection with the constitution and 

 physical make-up of fats which are uncommon in 



