Ester content

Pectins are generally classed according to their ester content as high methoxyl pectins (>50% of the carboxyl groups esterified) or low methoxyl pectins (<50% of carboxyl groups esterified) (pectic acid, methyl ester [9049-34-1]). Low methoxyl pectins, like algins, require calcium for gelation. 

Formylbenzoic acid and -toluic acid are deterrnined by high performance hquid chromatography or capillary electrophoresis. Gas chromatography can be used for the aldehyde ester content of dimethyl terephthalate, this being the counterpart of 4-form ylben zoic acid in terephthahc acid. 

All the additions meocioned. above considerably reduce the ester content. 

Distilled bergimot oil, oblaiued by distilling the residues from the expression proerss, is of very low odour value, liaving a specific gravity as low as 0 865 aud an ester content which may fall as low as b per cent. 

Hence, the acidity decreases in the course of vegetation the proportion of free linalol and the proportion of total linalol also decrease in the essence up to the time when the flowers are fully opened, whilst the proportion of ester increases then, when the flower fades, the essential oil becomes richer in linalol, whilst, on the other hand, its ester-content decreases. 

Specific gravity Optical rotation Refractive index Ester content... 

The Detection of Artificial Esters in Essential Oils.—The custom of valuing certain essential oils, such as lavender, bergamot, geranium, petit-grain, etc., by the determination of their ester-content, has led to the use of scientific adulterants in the form of artificial esters which have been deliberately employed for the purpose of misleading the analyst. Of course, the ester determination is not a true criterion of value, as most of this class of oUs owe their perfume value to various other bodies as well. The first compounds of this nature employed for adulteration were ethyl succinate and ethyl oxalate. For the detection of these in lavender oil the foUowing test was proposed by Guildemeister and Hoffman —... 

WAGNER J D, CEFALU W T, ANTHONY M S, LITWAK K N, ZHANG L and CLARKSON T B (1997) Dietary soy protein and estrogen replacement therapy improve cardiovascular risk factors and decrease aortic cholesteryl ester content in ovariectomized cynomolgus monkeys. ... 

The properties of ethylene-vinyl acetate copolymers vary widely with their ester content. At the lowest levels of vinyl acetate, they have physical properties that are similar to those of low density polyethylene. As the comonomer content increases, the material becomes less crystalline and more elastic. Copolymers made with the highest comonomer levels contain no measurable crystallinity. The resulting products are tough, flexible, and clear. The ester... 

FIG. 16 Alcohol and ethyl esters content before (BF) and after (AF) freezing of melon spheres cv. Rony not pretreated (RAW) or air dried at 80 °C up to 50% weight reduction without (AD) or following 60-min osmotic dehydration (OAD) in 60% (w/w) sucrose solution at 25 °C at atmospheric pressure (Lo Scalzo et al., 2001). 

Yang, L., Klang, J. and Cai, G., Process for making polyetheresters with high aromatic ester content, US Patent 5 612 444, 1997. 

Nakano, T. and Nakamura, H. (1986a). Viscoelasticity of esterified wood specimens I. Stress relaxation behaviour of caprated wood and the effect of ester content. Mokuzai Gakkaishi, 32(3), 176-183. 

Figure 7. Paint adhesion loss in salt spray exposure (ASTM B117) as a function of ester content for chain-extended epoxy-amine and epoxy-ester resin based coatings. All coatings applied at 20-25 urn film thickness to SAE 1010 steel test panels, baked, scribed and exposed for 24 hours to salt spray conditions.

A large and essentially unpredictable variability in the total oil and wax ester content of escolar was found with no clear correlation between the fish size and oil content. Also, no significant difference was found between the oil content of fish on the west coast and east coast of Australia, at least for specimens collected in summer (Ruello, 2004). 

Data from one escolar-associated outbreak found no correlation between BMI, age, health status, and amount of fish consumed to the severity and occurrence of symptoms, while other factors, such as variability in wax ester content in different fillet cut depths, could be relevant (Yohannes et al., 2002). Unlike some fish species, such as herring, which have uniform muscle oil content along the body (Brandes and Dietrich, 1953), muscle oil content in escolar and oilfish is not evenly distributed. Bone (1972) found that muscle oil content in oilfish increases from 14.5% (near vertebral column) to 24.7% (near the skin). A similar trend was also observed by Ruiz-Gutierrez et al. (1997) with higher oil content found in subcutaneous muscles than the periosteum. However, the lipid profile for... 

Ester Content (as Ethyl Acetate) — min 85 0 max 88.0%. It shall be detd in accordance with ASTM D1617-69, described in Annual Book of ASTM Standards, Part 20(1972), 736-39 Note 1 The method described in ASTM D1617— 69 applies not only to EtAcet, but also to other esters, such as N-butyl acetate, isopropyl acetate, acetate ester of ethylene glycol monoethyl ether, sec-butyl acetate, amyl acetate, dibutyl phthalate and iso butyl acetate... 

Bergamot is grown in the Italian province of Calabria, in Brazil, and in the Ivory Coast. The quality of the oil is determined by its ester content and varies with the species. Annual production is 100-200 t/yr. 

The composition of bitter orange oil differs from that of sweet orange oil i.e., its aldehyde content is lower and its ester content is higher [369-370a, 370d, 370e, 394, 423-428]. 

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