Fats and Related Substances

The acetyl value is defined as the number of mg of potassium hydroxide required to neutralize the acetic acid obtained by saponifying 1 g of the acetylated sample. 

Saponification Weigh accurately from 2 to 2.5 g each of the acetylated oil and of the original, untreated sample into separate 250-mL Erlenmeyer flasks. Add to each flask 25.0 mL of 0.5 N alcoholic potassium hydroxide, and continue as directed in the Procedure under Saponification Value, in this Appendix, beginning with Connect an air condenser.. .. Record the saponification value of the untreated sample as S, and that of the acetylized oil as S, then calculate the acetyl value of the sample by the formula 

Unless otherwise directed, weigh accurately about 5 g of the sample into a 500-mL Erlenmeyer flask, and dissolve it in 75 to 100 mL of hot alcohol, previously boiled and neutralized to phenolphthalein TS with sodium hydroxide. Agitation and further heating may be necessary to effect complete solution 

Method H (Animal Fats and Vegetable and Marine Oils) Prepare a solvent mixture consisting of equal parts, by volume, of isopropyl alcohol and toluene. Add 2 mL of a 1% solution of phenolphthalein in isopropyl alcohol to 125 mL of the mixture, and neutralize with alkali to a faint but permanent pink color. Weigh accurately the appropriate amount of well-mixed liquid sample indicated in the table below, dissolve it in the neutralized solvent mixture, warming if necessary, and shake vigorously while titrating with 0.1 TV potassium hydroxide to the first permanent pink color of the same intensity as that of the neutralized solvent before mixing with the sample. Calculate the acid value by the formula 

---

The concentration of fats and related substances in molasses is low analytical values depend on the extracting solvent.126 These tenaciously retained materials can be removed by fractionation of blackstrap on fuller s earth clay.70 Chromatography on a calcium silicate of the fat fraction of Cuban molasses led to the isolation of melissyl alcohol, a phytosterol fraction, chlorophyll a and a fat fraction containing a glyceride of linoleic acid.70 Stigmasterol and syringic acid are reported as ether-extractable constituents of molasses.127... 

Note 7 (A.V.) Unless otherwise indicated, determine the acid value (A.V.) as directed in M-l6, using phenolphthalein TS as the indicator unless another indicator is specified for an individual substance. Where Method II is specified, determine the acid value as directed in the general method, Appendix VII, Fats and Related Substances. 

Acid Value Determine as directed for Acid Value, Method II, under Fats and Related Substances, Appendix VII. 

Cold Test Proceed as directed under Cold Test, Appendix VII. Color Proceed as directed for Color (AOCS-Wesson) under Fats and Related Substances, Appendix VII. Use a 133.4-mm cell. Erucic Acid Determine as part of Fatty Acid Composition, Appendix VII. 

Acid Phosphatase Activity, 788, 789 Acid Phthalate Buffer, 848 Acid Value (Essential Oils and Flavors), 815, (Sl)168, (S 1)106 Acid Value (Fats and Related Substances), 820... 

Oils, fats, and waxes are all insoluble in water most of them, however, dissolve in organic solvents such as chloroform, ether, petrol, benzene, or the chlorinated hydrocarbons. They also form emulsions of varying degrees of stability when shaken with water containing soap or other emulsifying agents. Fats and related substances can be removed from textiles by three methods ... 

The potency of the tocopherols as antioxidants enables them to protect many of the readily oxidizable constituents of fats, including carotene and vitamin A. Some of the work in this field was reviewed briefly by Mason in Volume 2 of this series (1944). Golumbic.(2) studied the action of tocopherols in stabilizing animal fats and related substances, and found that their antioxidant power was shared by hydroxychromans and hy-droxycoumarans. Quackenbush, Cox, and Steenbock (3) found that... 

---