



Produced by Chris Curnow, Eric Skeet and the Online
Distributed Proofreading Team at http://www.pgdp.net (This
file was produced from images generously made available
by The Internet Archive)





Transcriber's notes:

Italics in the original work are here represented _between underscores_,
bold face text is represented =between equal signs=. Small capitals from
the original work are here represented by ALL CAPITALS.

More Transcriber's Notes may be found at the end of this text.




  Detection of the Common
  Food Adulterants

  BY

  EDWIN M. BRUCE

  INSTRUCTOR IN CHEMISTRY, INDIANA STATE NORMAL SCHOOL


  LONDON

  ARCHIBALD CONSTABLE & CO., LTD.

  10 ORANGE STREET, LEICESTER SQUARE, W.C.

  1907




  _Copyright, 1907_
  BY D. VAN NOSTRAND CO.




PREFACE


Because of the recent agitation of the pure food question throughout the
country, health officers, food-inspectors, and chemistry teachers and
students are constantly called upon to test the purity of various foods.
And this usually involves nothing more than making simple qualitative
tests for adulterants. In view of the fact that there is now no text or
manual devoted exclusively to the qualitative examination of foods, this
little book is offered to those who are interested in this work.

Its aim is to bring together in one small book the best and simplest
qualitative tests for all the common food adulterants. It contains a
brief statement of the adulterants likely to be found and the reason for
their use. It is hoped that it will be specially valuable to chemistry
teachers in furnishing excellent supplementary work in qualitative
analysis. But it is hoped that it will find its greatest usefulness in
contributing something toward the great pure food reform.

It is impossible to make due mention of all the sources from which these
various tests have been collected, but where possible, the author's name
has been associated with the test.

  TERRE HAUTE, IND.

  _March 25, 1907._




TABLE OF CONTENTS


  CHAPTER I                                                         PAGE

  DAIRY PRODUCTS                                                       1

  =Milk=--Adulterations of--Coloring matters--Annatto--Caramel--
  Coal-tar colors--Preservatives--Formaldehyde--Boric acid--Salicylic
  acid--Gelatin--Starch.

  =Butter=--Adulterations of--Coloring matter--Preparation of sample
  --Annatto--Coal-tar colors--Saffron--Turmeric--Marigold--Process or
  renovated butter--Oleomargarine--Cottonseed oil.


  CHAPTER II

  MEATS AND EGGS                                                       8

  Adulterations of--Fresh and smoked--Preservatives--Potassium
  nitrate--Boric acid--Sulfurous acid--Salicylic acid--Benzoic acid--
  Canned--Preservatives (same as those of fresh and smoked meat)--
  Heavy metals--Coloring matter (see under sausages, etc.)--Fish,
  salt, dried and oysters--Preservatives--Boric acid (same under
  smoked and fresh meat)--Coloring matter--Aniline red and cochineal-
  carmine--In sausages, chopped meat, preparations and corned meat--
  Starch--In sausages, deviled meat and similar products--Diseased
  meats--Horse-flesh in sausages and in mince-meat.

  =Eggs=--Test for age.


  CHAPTER III

  CEREAL PRODUCTS                                                     16

  =Flour=--Adulteration of--Alum--Copper sulfate--Substituted flours
  --General test--Corn meal in wheat flour--Wheat flour in rye flour
  --Ergot in rye flour.

  =Bread=--Adulterations of--Alum--Copper sulfate.

  =Ginger Cake=--Adulterations of--Stannous chlorid.


  CHAPTER IV

  LEAVENING MATERIALS                                                 20

  =Baking Powders=--Adulterations of--Tartaric acid (free or
  combined)--Tartaric acid (free)--Sulfates (calcium, etc.)--Gypsum--
  Ammonium salts--Alum.

  =Cream of Tartar=--Adulterations of--Tartaric acid (free or
  combined)--Aluminium salts--Ammonia--Earthy materials.


  CHAPTER V

  CANNED AND BOTTLED VEGETABLES                                       24

  Adulterations of--Preservatives--Preparation of sample--
  Formaldehyde--Sulfurous acid and the sulfites--Salicylic acid--
  Saccharin--Benzoic acid--