32 THE PRODUCTION OF MAPLE SIRUP AND SUGAR. 



It has been popularly believed that this " buddy " condition is 

 due to changes in the composition of the sap within the trunk of 

 the tree due to the renewal of vegetative activity in the tissues, and 

 that the alteration in color and flavor is a result of this change, but 

 Edson 1 has demonstrated that this " buddy " flavor is due to a large 

 extent to the action of microorganisms. When this peculiar odor 

 or flavor is noted in the sap no more sugar or sirup is made. 



Other conditions of sap are known as stringy sap, green sap, red 

 sap, and milky sap. In the first the sap is ropy or stringy and gen- 

 erally milky in color, the second designates one with a greenish to 

 greenish-brown color, the third shows a reddish sediment, and the 

 last has a peculiar milky appearance. None of these saps produce a 

 good sirup. Although they are spoken of as " sour saps." in reality 

 they are not sour in the strict sense of the word, as the acidity is 

 seldom much above the normal acidity of the sap, but they are 

 simply changed by the microorganisms. It is claimed by Edson that 

 when holes are running this peculiar sap, if the maker will rebore 

 the tree some distance from the old hole and put in new sterile or 

 clean spouts, normal sap will be obtained. The season may be pro- 

 longed to some extent by this procedure, but tapping more than the 



second time in one season is 

 not to be recommended. 



PROCESS OF MANUFACTURE 

 OF MAPLE SIRUP. 



CONCENTRATION OF SAP. 



On frosty mornings ice is 

 often found in the sap buckets 

 and in some cases the whole 



FIG. 11. Sirup skimmer. u _e 



mass of sap may be frozen. 



Makers differ as to whether this ice should be thrown away. ' Where 

 the whole quantity of the sap is frozen it is certain that it should not 

 be thrown away, but where ice is floating the ice should be, as the 

 freezing water would include very little of the sugar, and the sap 

 would, therefore, be concentrated to some extent. This method of 

 concentration is said to have been used by the Indians. 



When the sap is heated a scum forms on the surface. This is the 

 nitrogenous matter coagulating. Should there be fine sediment in 

 the sap as it runs to the evaporator this will be caught in the 

 coagulum and brought to the surface, when it should be carefully 

 skimmed off. 



Figure 11 shows a form of metal skimmer which resembles an 

 ordinary dust pan with the bottom perforated. This may have a 

 short handle, as shown, or a long wooden pole may be attached, 

 by means of which the scum can be raked to the near edge of the pan 

 or kettle and then lifted off. As the concentration goes on there 

 is a deposition of mineral matter, which may float around in the 

 thickening sap or may be deposited on the bottoms or sides of the 



iLoc. cit. 

 516 



