Banana aroma

Wp 1.4017, is a strongly fruity smelling liquid and has been identified in many fruit aromas. It is the main component of banana aroma and is, therefore, also used in banana flavors. 

Banana (Musa sapientum L.) is one of the most common tropical fruits, and one of Central America s most important crops. It is grown in all tropical regions and is one of the oldest known fruits [45]. From a consumer perspective, bananas are nutritious with a pleasant flavour and are widely consumed throughout the world [57]. Esters predominate in the volatile fraction of banana (Fig. 8.2). Acetates are present in high concentrations in the fruit and generally possess a low threshold. Isopentyl acetate and isobutyl acetate are known as the two most important impact compounds of banana aroma. Alcohols are the second most important group of volatiles in banana extracts. 3-Methyl-1-butanol, 2-pentanol, 2-methyl-1-propanol, hexanol, and linalool are the alcohols present in higher concentrations in the fresh fruit [45]. 

From the data presented, we conclude that most of the aroma descriptors detected in homogenized unblanched broccoli are due to the action of lyase. However, it appears that lipase may also contribute. None of the three enzymes, alone or in combination, gave the unripe banana aroma detected only in the unblanched sample. 

Mayr, D., Mark,T., Lindinger, W., Brevard, H., Yeretzian, C. (2003) Breath-by-breath analysis of banana aroma by proton transfer reaction mass spectrometry. International Journal of Mass Spectrometry, 223,743-756. 

Volatile flavor compounds may be formed from lipids via several different pathways. The primary pathways include a- and P-oxidation, and oxidation via lipoxygenase enzymes [8,9]. Some of the earliest work in this area was on the development of banana aroma by Tressl and Drawert [10]. Recent work showing pathways for the formation of several key volatiles derived from apple lipids are illustrated in Figure 4.2. They demonstrated the conversion of labeled acetate to acetate esters and labeled butanoate to butanoate esters by postchmacteric banana slices. They have further shown the conversion of hexanoic acid to hexanol by these tissues. 

Here are some additional examples of esters as aromas or flavors propyl acetate is the aroma of pears pentyl acetate is the aroma of bananas octyl acetate is that for oranges. 

Later, another research group suggested that not all of the volatile components found in large concentration in the commercial banana essence contributed to the aroma, such as 2-pentanone, 2-pentanol, butanol, and isobutyl acetate. However, isoamyl acetate, 2-pentanol acetate, 2-methyl-1-propanol, 3-methyl-... 

Aroma compounds of fresh banana from different countries (Martinique, Canary Islands, and Cote d Ivoire) were examined using the same extraction technique. As expected, differences in aroma composition were detected in the fruits of different origins. Isoamyl alcohol, isoamyl acetate, butyl acetate, and elemicine were detected by olfactometric analyses as characteristics of banana odour [7]. 

Esters also constitute a group of important flavour compounds. They are the main aroma components found in fruits (apples, pears,. ..). For example, bananas contain 12-18 ppm acetates. The price of the pure flavour compounds, when isolated from fruit, can range between 10,000 and 100,000 US /kg In the past, research has been carried out by our group about the microbial production of fruity esters by the yeast Hansenula mrakii and the fungus Geotrichum penicillatum [10]. A fermentation was developed whereby fusel oil was continuously converted into a mixture of 3-methylbutyl acetate (isoamyl acetate) and 2-methylbutyl acetate, the character impact compounds of banana flavour. 

White ports vary in style, depending on the duration of maturation. When aged in oak barrels for many years, the wine acquires a golden color that resembles a very old tawny wine and picks up a nutty character from the wood (Mayson, 2003). White ports destined to be drunk young are crisp, with an intense bouquet that combines aromas of melons and peach, with hints of citrus fruit, camomile, and lemon balm flowers. In contrast, white ports aged in wood present a complex aroma of tropical fruits, such as pineapple and banana, with a touch of almond and vanilla. 

Esters are among the most common acid derivatives. They are found in plant oils, where they give the fruity aromas we associate with ripeness. For example, the odor of ripe oil ITIITI3 ry OT thG bananas comes mostly from isoamyl acetate. Oil of wintergreen contains methyl sali- ChGlTI istfV Of Esters... 

Aroma components of citrus fruit juice128-132 are different from that of essential oils (see Section 4.15.4.5 for composition of the latter).133-135 Other familiar fruits like apples,136 grapes,137 strawberries,129 138 bananas,139 and pineapples140 were analyzed as well. Place of origin (e.g., grapes) and ripeness of the obtained fruit (e.g., pineapples), in many cases, bring substantial difference in its composition and enantiomeric properties (Table 14).141... 

The development of modern analytical methods has permitted the examination of volatiles from fresh fruit to determine when to pick the fruit. It is the usual concept that fruits are at their best when picked "tree-ripe". However, in extreme cases, as with bananas and pears, these fruits must be picked when hard and green and be permitted to soften and ripen off the tree. If these fruits are permitted to ripen on the tree, they become mealy and unacceptable. Some fruit, like strawberries and peaches, are of best quality when left to ripen on the plants. Apples have been shown to have the best aroma if picked almost ripe and develop the most aroma about a week or two after picking. 

Esters are responsible for the flavors and aromas of many fruits. Pentyl pentanoate smells like ripe apples. Ethyl butanoate has the aroma of pineapples, and 3-methylbutyl acetate smells like bananas although it imparts a pear flavor to foods. Most natural aromas and flavors are mixtures of esters, aldehydes, and alcohols. 

Natural fruit aromas are mixtures of certain organic compounds and esters. Synthetic aromas prepared in laboratories are simple mixtures of these same esters and organic compounds. They are used in perfumes, foods and drinks to give taste and pleasant smells. Ethyl acetate, for example, is a colorless liquid with an apple flavour it is known as apple ester and is used in perfumery as a fruit essence. Propyl acetate has the smell of pears, isopentyl acetate that of bananas and ethyl butyrate smells of pineapples. All are colorless liquids. Higher molar mass esters are odorless. 

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