Reichert-Meissl Value

Reichert-Meissl Value Determine as directed under Reichert-Meissl Value, Appendix YU. 

The Reichert-Meissl value is a measure of soluble volatile fatty acids (chiefly butyric and caproic). It is expressed in... 

Volatile Acids or Reichert-Meissl Value.—The separation of the volatile from the non-volatile acids is accomplished by distillation of the mixed fatty acids after they have been set free from the saponifica-... 

Flash pt 445 F (230"C) ignition temp 840"F (449I°C). Surface tension (dynes/cm) at 20 , 39.0 at 80 , 35.2. Acid value <4. Sapon no. 176-187. Iodine no. (Wijs ) 81-91. Reichert-Meissl value <0.5. Polenske value <0.5. Acetyl value 144-150. Hydroxy] value 161-169. Miscible with abs ethanol, methanol, ether, chloroform, glacial acetic acid. Dissolves in its own vol of petr ether or 95% alcohol. Does not dissolve to any extent in mineral oil, unless mixed with another vegetable oil. When heated to 300" for several hours it polymerizes and becomes miscible with mineral oil. 

Yellowish-white oil. Pleasant odor. Melting range initial 21°, complete transparency 3l . df 0,860. k 1.46757, n 1,46655 n, s 1.4646 n f 1,4636. Acid value 10-70 saponification value 220-230 iodine value 48-58 Reichert-Meissl value 16. Miscible with ether, chloroform, other vegetable oils, petrolatum, lanolin. 

Titer [7-26. Acid value 0.2-2.8. Saponification value 187-196. Iodine value 79-90. Thiocyanogen value 75-83. Hydroxy] value 4-12 Reichert-Meissl value 0.2-1.0. Unsaponifiable 0.5 -1,3%. Slightly sol in alcohnl. Miscible with ether, chloroform, carbon disulfide. 

Golden yellow oil, difficult to bleach. Not affected by temporary heating to 160 . dg 0.916-0,921. nS 1.470-1.473 n J 1.465-1 468. Titer (solidification pt) 24-28. Saponification value 1S -189. Acid value 4 120 (see above comments on the lipase content of the bran). Iodine value 99-108. Thiocyanogen value 69-76. Hydroxyl value 5-14. Reichert-Meissl value <0.5. Polenskd value <0.5. Hehner value 95.3. Unsaponifiable matter 3-5%. The high refractive index is ascribed to the presence ol squalene. Also contains other antioxidants such as tocopherols. Miscible frith hexane and other fat solvents. 

Edible drying oil, intermediate between soybean and linseed oil. dg 0.9211 -0.9215. Titer 15 -18. ng 1.472 -1.475. ng 1.4690-1.4692. Acid value 1.0-9.7. Sapotiif value 188-194. Iodine value 140-150. Thiocyanogen value 82.5-86.0. Reichert-Meissl value below 0.5. Hydroxyl value 2.9-6.0. Unsaponifiable below 1.5%. Thickens and becomes randd on prolonged exposure to air. Sol in the usual oil and fat solvents. 

Pale yellow to brownish-yellow oil. Slight characteristic odor and taste. The flavor of crude soybean oil has been described as paint-like and grass-like, and is somewhat distasteful to the palate of occidentals, djf 0.9)6-0.922. Flash pt 54Acid value 0.3 -3.0. Saponification value 189-195. Iodine value 127-138. Thiocyanogen value 77-85. Diene no. 0.7. Hydroxyl value 4-8. Reichert-Meissl value 0.2-0.7. Polenske value 0,2-1.0. Miscible with abs alcohol, ether, petr ether, chloroform, carbon disulfide. 

Reichert-Meissl value n. The number of ml of MIO potassium hydroxide solution required to neutralize the free volatile and soluble fatty acids in 5g of the sample under test. 

The test is somewhat cumbersome and can be found in all standard works on the examination of oils and fats, but the modification by Hawley of the method of Fritzsche, using digitonin, for routine examination of butter fats with border-line Reichert-Meissl values, considerably shortens the time and reduces the amount of material required and the manipulations involved. The method appears to be based on sound principles and sufficient practical detail is given in the original paper to ensure that it can be followed with ease. The procedure is ... 

Extensive data have been published on the Reichert-Meissl, Polenske, and Kirschner values of mixtures of butter fat, coconut, and palm kernel oils (Table 9) (24-26). Other average characteristics of butter fat are approximately as follows density at 60°C, 0.887 melting point, 38°C titer, 34°C and unsaponifiable matter, 0.4%. The optical properties of butter fat are misleading and are in part contributed by the nonglyceride components. 

Pale yellow oil. Bland, agreeable taste. d[ 0.922-0.926. dg 0.915-0.919. mp — IS". Titer 16-20. Acid value 0.6. Saponif value 188-194. I odine value 125-136. Thiocyano -gen value 78. Hydroxyl value 14-16. Reichert-Meissl... 

Cocoa fat and lipids In AOAC methodologies, the composition of fat and fatty acids in cocoa fat extracts are analyzed and characterized by physicochemical methods, including refractive index, melting point, saponification value and unsaponifi-able material, iodine number, Reichert-Meissl and Polenske values. 

---