
Recently edible coatings are one of the most useful innovations for extending the shelf life of fresh fruits and vegetables. Edible coatings act as barrier to gases (O 2 and CO 2 ) and moisture; produce similar effects to storage as in controlled atmosphere (Park, 1999) .

Edible coatings:-Edible coatings are thin layers that improve product quality which covers the surface of the food and it can be safely eaten as a part of the whole food. So, the composition of edible coatings has to be food grade or Generally Recognized as Safe ( (Baldwin, 1994; Ahvennainen, 1996; Kester & Fennema, 1986) . Edible coatings are new technique which is used to increase shelf life of whole or fresh-cut fruits & vegetables. Edible coatings have been developed for quality maintenance of fresh fruits and vegetables by preventing changes in color, aroma, appearance, taste & texture (Tharanathan, 2003) . Edible coatings are usually made from materials such as polysaccharides, proteins and lipids; the polysaccharides used in edible coatings are starches and modified starches, chitosan, alginates, gums, cellulose derivatives and Pectins (Krochta& Johnson, 1997).

Edible coatings provide a barrier against external elements and therefore enhance shelf life of fresh produce (Guilbert et al., 1996) by reducing water loss and gas exchange. The first kind of edible coatings were water-wax micro emulsions, used since the 1930s to increase brightness and color in fruits, as well as fungicide carriers (Saltveit, 2003) . Water loss is another problem that can be controlled with edible wax coatings. Edible waxes can also offer protection against cold damage under storage (Debeaufort et al., 1998) . . Aloe vera has medicinal properties and it is a semi-tropical plant. The Aloe vera had two type of gel one is "yellow latex (exudate)" and other is "clear gel (mucilage)", which is found in parenchymatus cells (Ni et al., 2004) .

Aloe vera containsmany beneficial complex components including glycoproteins, polysaccharides, salicylic acids, phenolic compounds, lignins, amino-acids, vitamins, saponins and enzymes which provide Aloe vera its many beneficial properties. The main component of Aloe vera extract is "Aloin and Aloe-emodin". Aloe vera extract is used as anti-fungal, anti-bacterial, anti-inflammatory (Serrano et al., 2006) . Aloe vera gel based edible coatings are good moisture and gas barrier.

Chauhan et al., (2014)analyzed theeffects of biodegradable Aloe vera gel coating on Grapes fruits and determined antifungal and antibacterial properties of Aloe veragel against pathogenic microbes. Aloe vera gel improves the texture of fruits and vegetables by suppressing respiration, reducing microbial growth and retaining volatile flavor components; it also increases the shelf-life of grapes fruits for 40 days. 
5.
Lemongrass 

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