MAPLE SIRUP PRODUCERS MANUAL 



TESTING MAPLE SIRl P FOR IINVERT SUGAR 



113 



The relation between the invert sugar con- 

 tent of maple sirup and its suitability for mak- 

 ing maple cream is as follows: 

 Invert sugar 

 content of 

 sirup (percent) Suitability for cream 



0.5 to 2 The right amount of invert sugar 



for making a fine-textured 

 cream — one that feels smooth to 

 the tongue. 



2 to 4 Can be made into cream if sirup is 



cooked until it is 2° to 4° F. hotter 

 than temperature called for in 

 standard recipes for cream. 

 4 or more Not suitable for cream. If used, su- 

 crose will not crystallize, or it will 

 crystallize only if sirup is heated 

 to a much higher-than-standard 

 temperature. Such cream will be 

 too fluid and probably will sepa- 

 rate a few days after it is made. 



Two tests are available for determining the 

 invert sugar content of maple sirup. The simple, 

 or short-cut, test merely shows whether the 

 sirup contains less than 2 percent of invert 

 sugar and is therefore suitable for creaming. 

 The other is a quantitative test. It measures 

 invert sugar in amounts up to 7 percent, the 

 upper limit normally found in maple sirup. 



Simple Test 



The simple test for determining the invert 

 sugar content of maple sirup has been adapted 

 from a standard test for determining the sugar 

 in urine (78, 80). The test is made by first 

 preparing a sirup-water mixture (1 part of sirup 

 to 20 parts of water) and then color testing the 

 diluted sirup. It can be made in 3 or 4 minutes. 



Equipment 



The few pieces of equipment required to 

 make the tests can be obtained from the local 

 pharmacy. The following items are required: 



(1) Clinitest tablets'" obtainable at pharmacy. 



(2) Two medicine droppers. 



(3) A test tube, about V2 inch in diameter and 



3 or 4 inches long. 



(4) A sample of the sirup to be tested (1 

 cupful). 



(5) One medicine glass, calibrated in ounces. 



(6) One glass measuring cup, calibrated in 

 ounces. 



(7) Test tube holder. 



(8) Two 8-ounce, clean and dry drinking 

 glasses. 



(9) One 1-quart glass fruit jar and cover. 



(10) One "Clinitest" color scale. 



(11) Water (20 fluid ounces). 



M„ki 



tlu- Test 



'" Trademark. This product is one of several that may 

 be used by diabetics in testing for sugar in urine. 



(1) Carefully pour enough of the test sirup 

 into a medicine glass to bring the level of the 

 sirup exactly to the 1-ounce (2 tablespoons) 

 mark. If too much (more than 1 ounce) is added, 

 empty the sirup out of the medicine glass, wash 

 and dry it, and start over. 



(2) Measure 2V2 cups of water and transfer it 

 to the quart jar. 



(3) Make the l-to-20 solution by pouring the 

 fluid ounce of sirup into the jar containing the 

 2V2 cups (20 fluid ounces) of water. 



(4) Pour some of the water-sirup mixture into 

 the medicine glass and return it to the jar. 

 Repeat this three or four times to be sure that 

 all the sirup has been transferred to the water 

 in the jar. Mix the contents of the jar thor- 

 oughly by stirring with a spoon or with a 

 portable electric mixer. 



(5) Place the test tube upright in the holder. 

 (The holder can be a 1-inch-thick block of wood, 

 2 inches square with a ''/le-inch hole ^/4 inch 

 deep.) 



(6) Fill a clean, diy medicine dropper with the 

 diluted (1:20) sirup in the fruit jar. Hold the 

 dropper upright above the test tube and let 5 

 drops of the diluted sirup fall into the test tube. 



(7) Fill another clean and dry medicine drop- 

 per with water and add 10 drops of water to the 

 test tube. 



(8) Place a Clinitest tablet, freshly removed 

 ft'om the bottle or wrapjier, in the test tube. As 

 the tablet dissolves, it causes the contents of 

 the tube to boil. Do not remove the tube from . 

 the holder while the solution is boiling. 



