Fruit waxy coatings

Prunol Urson) (ursane triterpene) Other (Ericaceae), Plantago major (Plantaginaceae), Prunella vulgaris (Labiatae), Malus sp., Pyrus sp. (Rosaceae) [fruit waxy coat] cytotoxic, anti-leukaemic] 9.7o... 

The leaves and fruit of many plants bear a waxy coating made up of alkanes that prevents loss of water In addition to being present m beeswax (see Problem 2 6) hen triacontane CH3(CH2)29CH3 is a component of the wax of tobacco leaves... 

Natural gas is an abundant source of methane ethane and propane Petro leum IS a liquid mixture of many hydrocarbons including alkanes A1 kanes also occur naturally m the waxy coating of leaves and fruits... 

VLCFAs enter the body from two sources diet and biosynthesis. There are only a few foods that are high in VLCFA (fatty meat, nuts, and the waxy coating of fruits and vegetables) so it is relatively easy to restrict dietary intake. The more difficult problem is turning off the natural biosynthetic pathway. 

Liquid alkanes with 9-17 carbon atoms have higher boiling points and are found in kerosene, diesel, and jet fnels. Motor oil is a mixture of liquid hydrocarbons and is used to lubricate the internal components of engines. Mineral oil is a mixture of liquid hydrocarbons and is used as a laxative and a lubricant. Alkanes with 18 or more carbon atoms are waxy solids at room temperatnre. Known as paraffins, these compounds are used in waxy coatings for fruits and vegetables to retain moisture, inhibit mold growth, and enhance appearance. Petrolatum, or Vaseline, is a semisolid mixtnre of liquid hydrocarbons with more than 25 carbon atoms nsed in ointments and cosmetics and as a lubricant. 

The solid alkanes that make up waxy coatings on fruits and vegetables help to retain moisture, inhibit mold, and enhance appearance. 

Waxes are mixtures of esters of long-chain carboxylic acids with long-chain alcohols. The carboxylic acid usually has an even number of carbons from 16 through 36, while the alcohol has an even number of carbons from 24 through 36. One of the major components of beeswax, for instance, is tria-conty hexadecanoate, the ester of the C30 alcohol triacontanol and the Cib acid hexadecanoic acid. The waxy protective coatings on most fruits, berries, leaves, and animal furs have similar structures. 

Waxes are common in living organisms. The feathers of birds are coated with wax to make them water repellent. Some vertebrates secrete wax in order to keep their fur lubricated and water repellent. Insects secrete a waterproof, waxy layer on the outside of their exoskeletons. Wax is also found on the surfaces of certain leaves and fruits, where it serves as a protectant against parasites and minimizes the evaporation of water. 

The fruit peel is often coated with a waxy layer. In addition to the esters of higher fatty acids with higher alcohols, these waxes contain hydrocarbons, free fatty acids, free alcohols, ketones and aldehydes. The ester fraction in apples and grapes predominantly consists of alcohols of 24, 26 and 28 carbons, but their fatty acid patterns differ. Ap-... 

Uses Food emulsifier, lubricant, solvent, plasticizer and coating material for foodstuffs (meat prods., cheese, dried fruit, nuts), and cosmetics can be combined with hydrophilic emulsifiers to increase whipping props, in shortenings/topping Regulatory EU E472a, FAOAWHO compliance Properties Ivory waxy slabs, faint char, odor misc. with fats and oils Insol. In water m.p. 34-38 C HLB 2-3 iodine no. 3 max. sapon. no. 310-340 hyd. no. 75-95 flash pt. > 100 C 100% cone. 

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