Oiganic acids functions

Oiganic colloids (mainly humic substances) also possess large specific surfaces and are generally negatively charged due to the acidic functional groups that tend to dissociate or polarize. Examples of such groups include carboxyls (R-COOH), quinones (-Ar=0), phenols (-Ar-OH), and enols (R-CH=CH-OH). (See Section 5.4.2 for a more complete discussion of humic substances.)... 

Edible films and coatings can be carriers of antioxidants (phenolic compounds such as butylated lydroxyanisole, propyl gallate, butylated hydroxytolene, tocopherol, citric acid, ascorbic acid, or natural compounds from heib extract) and antimicrobials (oiganic acids and their salts such as benzoic acid, soibic acid, propionic acid, chitosan, plant essential oil extracts, and so on.) to enhance their functional properties as active packagings (Janjarasskul and Krochta, 2010). Moreover, they can be carriers of nutrients, flavors, and colors to improve food nutritional and sensoiy quality. 

At room temperature, ca 60 wt % ethylene oxide is needed to solubilize the fatty acids. Surface activity of the ethoxylates is moderate and less than that of alcohol or alkylphenol ethoxylates (84). The ethoxylates are low foamers, a useful property in certain applications. Emulsification is the most important function. Its importance is reflected in the wide range of lipophilic solubilities available in the commercial products. Like all oiganic esters, fatty acid ethoxylates are susceptible to acid and alkaline hydrolysis. 

Divalent cations, particularly calcium, have been shown to enhance fouling of membranes with natural oiganic matter (NOM). Because is it s acidic nature, NOM can form complexes with dissolved metal ions. The strongest bonds occur with Ccdcium. This is a function of the size of the metal ion, it s electronic chaige, and the... 

Many familiar substances are oiganic compounds. Some examples include aspartame, the artificial sweetener in the sugar substitute Equal and in many diet sodas salicylic acid, found in some acne medicines and wart-removal treatments and amphetamine, a stimulant used to treat narcolepsy. attentiMi-defidt hyperactivity disorder (ADHD), and obesity. Identify the functional groupfs) in each molecule ... 

There is still no real knowledge of the precise role or roles of vitamin C in the living oiganism (Harris, 1953 Meiklejohn, 1953). The intense reducing property of ascorbic acid suggests a function in oxidation-reduction, and a relation to the oxidation of tyrosine does seem to be established. The functional activity of formative cells in the teeth... 

Fig. 2.52 Distribution of water between the aqueous phase and the oiganic phase (tri-n-octyl-amine + diluent) at 25 °C as a function of citric acid concentration in the aqueous phase [241], - methyl isobutyl ketone, m.j,Q =1.21 mol kg" - toluene, mol kg" - chloro-...

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