CUEING, COOLING AND BALING. 211 



subjected to a heat of over 160 degrees Fahren- 

 heit, there is visible to the naked eye, a change 

 in the appearance of the lupulin in many samples 

 that can be selected in a flooring of hops, though 

 not all will show the effect alike. We are led to be- 

 lieve from this that either the length of time after being 

 dried that the hops are subjected to the current of heated 

 air, or else some u:iKnown condition of the hops before 

 going on the kiln, governs this visible sensibility to heat; be 

 that as it may, the fact stands out prominently so that any 

 observing hop grower can demonstrate it with no expense 

 and but little trouble. As the heat is increased the 

 change becomes more apparent, until at about 180 degrees 

 the globules begin to disappear and run together, present- 

 ing a dull brown or red appearance, of all shades, according 

 to the degrees of intensity, and, as we believe, duration of 

 time the hop has been subjected to this high heat. If to the 

 naked eye there is a visible change in this delicate substance, 

 from the effects of heat, how much more apparent it becomes 

 when subjected to the rigid scrutiny of the chemist or the 

 practical test of the brewer. The extract or bitter principle 

 of the hop, according to Thausing, assumes a reddish-yel- 

 low color when heated above 140 degrees Fahrenheit, and 



when cooled off can be rubbed into a fine powder (At 



212 degrees F. the hop bitter swells up under decomposition, 

 and combustion takes place, with a sooty flame.) And yet, 

 an American authority recommends ISO degrees F. as a 

 safe temperature. We know from experience that it fair- 

 ly cooks the hops and destroys much of their value." 



Whitehead, writing in 1897, confirms his earlier 

 statements in 1893, and in still earlier years, to the 

 effect that "the merciless treatment of stewing or bak- 

 ing, to which English hops are subjected, causes an 

 absolute, visible loss of lupulin, besides the loss of 

 ethereal essences." English hops, dried slowly at a 

 temperature never rising above TOO degrees F., were 

 found on analysis to contain larger quantities of resin, 

 oil and bitter principles, and at the same time consider- 

 ably less moisture, than Spalt hops cured by the same 

 process. Worcester hops dried in this gradual man- 

 ner were found to be uniformly rich in desirable quali- 

 ties and to have far less moisture than the best brands 

 from other hop-producing regions of the continent or 

 America cured in the ordinary way. 



