barrett] THE MOST USEFUL HOUSE PLANT 21 



of digestibility and attractiveness which we characterize by the 

 word "done." 



Bread has been the staff of life since pre-historic times; and 

 since, because of the presence of wild yeast in the air, a mixture 

 of meal and water ferments in the course of a day in the warm 

 climates where history began to be made, we may conclude that 

 raised bread is almost as old as the unleavened form. There 

 are numerous varieties of it, different nations as well as individuals 

 having originated certain types. It is the first food whose name 

 you may learn when you study a new language and it has figured 

 in the literature of all nations. Besides being the best known 

 food it is probably the most popular in the long run, and by most 

 people is considered indispensable to a meal. There is no waste 

 in bread, and although it contains very little protein it yields per- 

 haps the greatest amount of nourishment of any food for the least 

 labor and cost. 



And yet after all this time and experimentation, voluntary 

 and involuntary, on the part of housewives, bakers, physiologists, 

 and chemists, we are still in doubt as to some of the processes 

 that go on and we still find a loaf of good bread a very difficult 

 thing to make. There remain plenty of problems to be solved, 

 and of a nature not to be despised by research workers. Let me 

 leave for your consideration and solution a few of the questions 

 to be answered in the future, as formulated by Robert Kennedy 

 Duncan in "Some Chemical Problems of To-day." ** 



What is the best yeast strain for each kind of bread ? 



What is the nature of the best soluble proteids for yeast food 

 and what should be their proportionate quantity? 



What mineral substances best accelerate the action of yeast? 



What is the actual action of yeast in the gluten ? 



What is the proper temperature of bread fermentation ? 



What is the best way to nullify the action of maleficent bacteria 

 and to accentuate or utilize the influence of bacteria that are 

 beneficent ? 



