70 



AGRICULTURE HANDBOOK 134, U.S. DEPT. OF AGRICULTURE 



Always start with a fresh supply of the reagent 

 at the beginning of each sirup season. 



Rcrlaiininff Buddy Sirup and Sap 



Many sirupmakers make buddy sirup from 

 the late runs of sap. Although this practice 

 should not be encouraged because of the very 

 low price commanded by buddy sirup, it is 

 made — often unknowingly. ^ 



Buddy sap and buddy sirup can be treated by 

 a fermentation procedure to remove their un- 

 palatable flavor {136, 137). Because this process 

 requires special equipment and a high degree of 

 technical conti'ol, it has not been commercially 

 successful. Recently a new procedure has been 

 developed using ion-exchange resins to remove 

 the buddy off- flavor (36a). This process removes 

 the amino acids believed to be responsible for 

 the buddy flavor of maple sirup. The cost of this 

 treatment on a commercial scale is estimated to 

 be less than $1 per gallon of sirup. 



Riilo of Sirupinakin^ 



The following rules should be followed in 

 sirupmaking: 



(1) If possible, test all sap for buddiness; but 

 especially test that produced late in the spring 

 or following a warm spell. Do not use buddy 

 sap. 



(2) Do not use fermented sap. To keep the sap 

 from fermenting, collect it often. Do not allow it 

 to stand in the buckets or tanks, and keep it 

 cold. If there is a small flow of sap that does not 

 warrant collecting, dump it. At least once dur- 

 ing the season, wash the sap-gathering equip- 

 ment (buckets, pails, and tanks) and sanitize 

 the equipment with a 10-percent hypochlorite 

 solution. 



(3) Handle the sap as quickly as possible. The 

 sooner sap is evaporated after it has been 

 obtained from the tree, the higher the grade 

 and the lighter the sirup that will be produced. 

 The faster sap is evaporated to sirup, especially 

 during the last stages of evaporation when the 

 solids concentration is highest, the lighter the 

 color and the higher the grade of the sirup. 



(4) Keep sap and equipment clean. Cleanli- 

 ness is a must in maple sirupmaking for, aside 

 from its esthetic aspects, cleanliness is the only 

 way to control microbial contamination and 



subsequent growth in the sap. Sirup made from 

 sap in which growth of micro-organisms has 

 occurred tends to be dark colored and low in 

 grade. 



(5) By means of a hydrometer or other suita- 

 ble instrument, measure and record the sugar 

 content of the sap produced by each tree and 

 also the sugar content of each batch of sap in 

 the storage tanks. 



(6) Store sap in a cool place. 



(7) Store sap in tanks exposed to daylight (not 

 necessarily direct sunlight). 



(8) Cover the tanks with material transparent 

 to ultraviolet radiation, such as clear plastic. 



(9) Provide tanks having opaque covers with 

 germicidal lamps. 



Grades of Sirup 



It is generally believed that the best sirup is 

 made early in the season during the first and 

 second runs of sap. However, this is not neces- 

 sarily true, as was demonstrated in 1954 when 

 sirup made early in the season was darker than 

 some made later. The important factor is the 

 atmospheric temperature. Warm weather favors 

 microbial growth, and the byproduct of this 

 growth — invert sugar — affects the color and 

 grade of the sirup. It is only coincidental that 

 the weather is usually cooler at the beginning 

 of the season and microbial growth is low. 



Sap that is essentially sterile contains very 

 little invert sugar and will usually produce a 

 light-colored, light-flavored, fancy sirup. Some- 

 times, as in 1954, the weather at the onset of 

 the season is warm, and fermentation occurs. 

 The result is that the first-run sirup is darker 

 than expected. If conditions are reversed later 

 in the season, fancy sirup will be produced, for 

 with cold weather little or no fermentation of 

 the sap occurs. 



Making light-colored sirup with sterile sap 

 that is veiy low in invert sugar does not test a 

 sirupmaker's skill. However, skill is required to 

 produce light-colored sirup from sap rich in 

 invert sugar (with a high microbial count). This 

 skill is actually a measure of how fast the 

 sirupmaker can evaporate the sap to sirup. 



Sirup can be darkened — changed from U.S. 

 Fancy to U.S. Grade A, or from U.S. Grade A to 

 U.S. Grade B, etc.— by prolonging the heating 



