Glycerol value chain

The saponification value is the amount of alkali required to saponify a defined amount of sample. It is expressed in mg potassium hydroxide (KOH) per g sample. The procedure involves the use of excess alcoholic KOH, which catalyzes the saponification/release of the free fatty acids from the glycerol backbone. The unreacted KOH is then back-titrated with standardized hydrochloric acid (HC1) using phenolphthalein as the indicator. The amount and normality of the HC1 used for neutralization can then be used to calculate the saponification value. The saponification value provides evidence as to the relative chain lengths of the fatty acids in the system. 

Figure 24.8. Graphic presentation of the variation in specific optical rotation values for enantiopure MLM type asymmetrically structured TAG products 16a-16h, when varying the chain length of the saturated fatty acid located at the sn-3 position of the glycerol backbone.

Solvent fractionation is the term used to describe the crystallization process of a desired fat fraction from oil that is solubillized in a suitable solvent. Fat fractions may be selectively crystallized at different temperatures, after which the fractions are separated and the solvent removed. This procedure is suitable for the preparation of value-added products. The production of cocoa butter equivalents, cocoa butter substitutes, cocoa butter replacers, and medium-chain triacyl-glycerols (MCTs) are well-known applications for this type of fractionation. 

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