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



Brix ° Baume ° Brix ° Baume " Brix ° Baume 



Measuring Solids (Content 



32.0 17.7 58.0 31.5 64.8 34.9 The effect of temperature on density is more 



32.5 17.9 58.5 31.7 64.9 35.0 pronounced in siruD than in sap {H6). Since 



33.0 18.2 59.0 32.0 . . ■ ' ^u \.u e u 



33.5 18.5 59.5 32.2 65.0 35.0 ^^^"P '^ "'^^^ viscous than sap, the followmg 



34.0 18.7 65.1 _ __ 35.1 precautions should be observed: 



34.5 19.0 gQQ ^2 5 65.2 35.1 No sirup must be allowed on the part of the 



35.0 19.3 gjj J 32.5 -~^^-^ ^^-^ hydrometer stem that is exposed above the 



35.5 19.6 gQ2 32.6 ^^■'^ ^^-^ surface of the sirup being tested. The hydrome- 



60.3 32.6 • • ter must be clean and dry, and it must be 



36 n 19 8 fin 4 "^9 1 oo.b 35. o 



365 ' ' 20 1 qp 7 65.7 35.4 inserted with clean fingers. Also, it must not be 



37.0 V. ... 2QA 606 32 8 ^^-^ ^^-^ submerged below its floating position and per- 



37.5 20.6 60.7 32.9 ^^'^ ^^-^ mitted to rise. The sirup on the exposed stem of 



38.0 20.9 60.8 32.9 the hydrometer would add weight, the hydrom- 



38.5 21.2 60.9 33.0 ^^'^ ^^-^ 



39.0 21.4 



60.9 33.0 • • eter would float too deep in the sirup, and the 



48.5 26.5 



49.0 26.8 



66.1 35.6 



go g 21 7 66.2 __ 35.7 observed reading would be too low. 



4o!o ~ ~- 22^0 ^^'^ ^^'^ 66.3 35.7 Sirup at room temperature is viscous, and 



40.5 22.2 „ ■ „ „■ 66.4 35.8 therefore 30 seconds or more will be required 



61 3 V 33 2 ^^'^ ^^'^ fo^ ^^^ hydrometer to settle to its point of rest. 



41.0 22.5 61.4 33.2 gg",, org If the observed hydrometer readings are made 



41.5 22.8 61.5 33.3 gg'g gg^^ too soon, they will be too high. Also, if the 



42.0 23.0 61.6 33.3 gg g gg q diameter of the hydrometer cup is too small, or 



43 23 6 618 33 4 if the hydrometer is floated too close to the wall 



43.5 23.8 619 ... 33^5 ^'"^ ^^'^ of the cup, or if the cup is tilted, the movement 



44.0 24.1 ^'^■^ 36.1 of i]]Q hydrometer will be restricted and the 



44.5 24.4 g2(, gg g 67.2 36.2 observed reading will be incorrect. 



45.0 24.6 g2^ gg g ^^-^ ^^-^ rpQ determine accurately the sugar content of 



• • 62.2 33.6 67.5 36.3 maple sirup, use a hydrometer calibrated in 0.1° 



4gjj 62.3 33.7 67.6 36.4 Brix (7.46). Place the sirup in a hydrometer cup 



46.5 '/.'".'. 2bA 625 33 8 ^''"^ ^^'^ whose depth is equal to, or slightly greater 



47.0 25.7 62^6 33.8 67 9 365 than, the overall length of the hydrometer and 



47.5 26.0 g2 7 339 ' ' whose diameter is at least IV2 times larger than 



'!?■? ??■? 62.8 33.9 ggQ ggg the diameter of the hydrometer bulb. Fill the 



62.9 34.0 



;.l 36.6 hydrometer cup to the top with sirup, gently set 



495 """"'" 27^^ 68.2 36.7 the hydrometer into the sirup, and allow it to 



50.0 27.3 ^^"^ ^^-^ 68.3 36.7 settle unaided until it comes to rest. When the 



50.5 27.5 f^\ l^-\ 68.4 36.8 hydrometer comes to rest, at least 30 seconds 



63.3 34.2 68.6 36 9 after it IS placed m the cup, carefully hit the 



51.0 27.8 63.4 34.2 68.7 36.9 cup SO that the liquid surface is at eye level and 



51.5 28.1 63.5 34.3 68.8 37.0 read the mark on the hydrometer scale at the 



52.0 28.3 63.6 34.3 68.9 37.0 point of intersection of the hydrometer stem 



«A fA MS ^11 and the liquid surface (fig. 99). This value is the 



53.0 28 9 00.0 o4.4 fiQO '^7 1 <^ n • c \ 



53.5 29.1 63.9 34.5 egj gfj observed hydrometer reading ( Brix) of the 



54.0 29.4 6a2 __"."'" 37^2 ^irup. 



54.5 29.6 64.0 34.5 69.3 37.2 Although most hydrometers are calibrated 



55.0 29.9 64.1 34.6 69.4 37.3 for use at 68" F., this does not mean that sirup 



55.5 30.2 64.2 34.6 69.5 37.3 ^lust be heated or cooled to 68° before its 



56.0 ._.... 30.4 61:4 " - 1^1 Z VZ" 111 density can be measured. Actually, the ob- 



56.5 30 7 64 5 34 8 69.8 37 5 served density can be measured at any temper- 



57.0 30.9 64.6 34.8 69.9 37.5 ature and the true density, or Brix value, calcu- 



57.5 31.2 64.7 34.9 70.0 37.6 lated, if the exact temperature of the sirup at 



