Strawberry aroma

Since I wasn t likely to be eating it, I doubted it was for seasoning, despite the strawberry aroma of the liquid. It could have been used as a preservative, but the remaining ingredients were more likely to kill microbes than salt was. 

C6Hg03, Mr 128.13, is a constituent of pineapple and strawberry aroma and is also found in other foods. It forms colorless crystals (mp 77-79 °C) with a relatively weak, nonspecific odor. Dilute solutions develop a pineapple, strawberry-like odor. It can be prepared by cyclization of hexane-2,5-diol-3,4-dione in the presence of an acidic catalyst [186]. The dione is the ozonization product of 2,5-hexynediol, which is obtained by ethynylation of acetaldehyde. 

Sugars, acids and aroma compounds contribute to the characteristic strawberry flavour [85]. Over 360 different volatile compounds have been identified in strawberry fruit [35]. Strawberry aroma is composed predominately of esters (25-90% of the total volatile mass in ripe strawberry fruit) with alcohols, ketones, lactones and aldehydes being present in smaller quantities [85]. Esters provide a fruity and floral characteristic to the aroma [35,86], but aldehydes and furanones also contribute to the strawberry aroma [85, 87]. Terpenoids and sulfur compounds may also have a significant impact on the characteristic strawberry fruit aroma although they normally only make up a small portion of the strawberry volatile compounds [88, 89]. Sulfur compounds, e.g. methanethiol. 

From the wine aromas of Pollux, Castor, and Riesling grapes, Rapp et al. and Schreier and Paroschy have isolated an undesirable strawberry aroma by GC-MS (80V13, 81MI112). This lactone was characterized as 2,5-dimethyl-4-hydroxy-2,3-dihydro-3-furanone 8 ("furaneol") having an odor threshold of 50-100 ppb. 

Maltol occurs as a white, crystalline powder with a characteristic caramel-butterscotch odor, and is suggestive of a fruity-strawberry aroma in dilute solution. One gram dissolves in about 82 mL of water, in 21 mL of alcohol, in 80 mL of glycerin, and in 28 mL of propylene glycol. 

Ulrich, D., Hoberg, E., Rapp A. and Sandke, G. (1997) Flavour analysis in plant breeding - solid phase micro extraction of strawberry aroma compounds, in H.-P. Kruise and M. Rothe (Eds) Proceed. 5th Wartburg Aroma Symp., Eisenach (Germany), Eigenverlag Univ., Postdam. 

Polesello S, Lovati F, Rizzolo A, Rovida C. Supercritical-fluid extraction as a preparative tool for strawberry aroma analysis. J High Resolut Chromatogr 1993 16 555-559. 

CH3(CH2)4CHO, C6H120, Mr 100.16, 6p10i.3kPa 128 °C, 4° 0.8139, rag0 1.4039, occurs, for example, in apple and strawberry aromas as well as in orange and lemon oil. It is a colorless liquid with a fatty-green odor and in low concentration is reminiscent of unripe fruit. 

Strawberry flavor The strawberry aroma is made up of caramel-like [ impact compounds Furaneol, mesifuran (see Furaneol )], fruity [ fruit esters, 4-decanolide (see alkanolides)], green [( )-2- hexen-l-ols, ( )-2- hexenals, 2-hexenyl acetate (see fruit esters)], and flowery notes ( linalool, methyl anthran-ilate). Particularly important fruit esters are ethyl butanoate and hexanoate as well as the corresponding methyl esters. Free acids such as 2-methylbutanoic acid (C5H,o02, Mr 102.13, CAS [116-53-0]) and trace substances, e.g., dimethyl sulfide and vanillin, round off the aroma. 

Isci A, Sahin S, Sumnu G. 2006. Recovery of strawberry aroma compounds by pervaporation. J. Food Eng. 75 36 2. 

Ozdemir E, Akgedik K, Akdogan S, Kansu E. The lollipop with strawberry aroma may be promising in reduction of infusion-related nausea and vomiting during the infusion of cryopreserved peripheral blood stem cells. Biol Blood Marrow Transplant 2008 14(12) 1425-8. 

Perez, A.G., et al. (2002) Biosynthesis of strawberry aroma compoimds through amino acid metabolism. J. Agric. Food Chem. 50, 4037-4042... 

Pineapple Ananas comosus, Bromeliaceae) aroma consists of about 200 alcohols, esters, lactones, aldehydes, ketones, monoterpenes, sesquiterpenes and other volatiles. About 80% of the total volatile substances are esters. The main components in the green fruit are ethyl acetate, ethyl 3-(methylthio)propionate (8-189) with a distinctive pineapple aroma and ethyl 3-(acetoxy)hexanoate (8-190). The ripe fruit contains, as the main esters, ethyl acetate, (2J ,3i )-butane-2,3-diol diacetate (8-191) and ketone 3-hydroxy-butan-2-one. An important compound for the typical character of pineapple aroma, as in strawberry aroma, is 2,5-dimethyl-4-hydroxy-2//-furan-3-one (furaneol), present as a glycoside, and 2,5-dimethyl-4-methoxy-2H-furan-3-one. 

B. Perceptual Interactions of Strawberry Aroma with Sugar and Acids in Solution... 

A balanced strawberry flavor was blended from 150 ppm strawberry aroma (Fraise 504877T, Firmenich SA, Geneva, Switzerland), 60g/L sucrose, 1.0 g/ L citric acid, and 0.2 g/L malic acid. 

Two syringe pumps, configured as shown in Fig. 1, were used to pump and mix solutions of strawberry aroma, sucrose, acids (citric and malic... 

In-nose release of strawberry aroma was measured by using the MS-Nose (Micromass, Manchester, UK). A pumping regimen, in which the strawberry aroma was removed after 30 sec and replaced after 3 min, was delivered to each of seven panelists, while conducting simultaneous nose-space sampling to the MS-Nose. The ion with mjz 117 (ethyl butyrate) was used to follow strawberry aroma release. The in-nose concentration of ethyl butyrate was calculated by comparison with the signal for a calibrant of known concentration [10]. 

The removal of any of the flavorings (adds, sucrose, or strawberry aroma) during the pumping experiment resulted in reduced sensory perception of strawberry flavor (Fig. 3). By far the greatest impact on overall strawberry flavor was due to sucrose. In any run in which sucrose was removed from the mixture (runs 2, 4, 6, and 7 in Fig. 3) there was a large and sudden decrease in strawberry perception, practically to zero. This effect was reversed when the flow of sucrose was switched on again after 3 min and perceived intensity returned to its original level of around 100. 

When the add and strawberry aroma were turned off either separately (runs 1 and 3) or together (run 5) they had less of an effect on the perceived strawberry intensity than sucrose. Stopping the flow of acids caused the perceived strawberry intensity to fall to just above 50%, whereas removal of the strawberry aroma caused the intensity to decline to 60% of initial perception. A minimum of 60% was also reached when both the acid and the volatile were turned off together. These three curves were considerably different from the rest. In runs in which the aroma was removed, but sucrose... 

Figure 3 Mean time-intensity curves for strawberry flavor perception, resulting from pumping and mixing solutions of citric/malic acids, sucrose, and a strawberry aroma. Initially all three components (acids, sucrose, strawberry aroma) were present. After 30 seconds either one, two, or all three of the solutions were replaced by an equivalent flow of water (see key). After 180 sec, the mixture was restored to its initial state. 1, Aroma off 2, sucrose off 3, acid off 4, aroma and sucrose off 5, aroma and acid off 6, acid and sucrose off 7, all off.

Studies on pumped mixtures of sucrose, citric/malic acids, and strawberry aroma gave evidence of the perceptual interactions among these three components in determining overall perceived strawberry flavor. Sucrose was the key driver of strawberry flavor perception and caused the most drastic and rapid reductions in perceived intensity when it was removed from the mixture. 

Finally, we comment that PTR-MS has been used to draw a link between the volatile compound release and the genetic factors through the emission of various esters from cultivated strawberries [65]. Esters, which are produced via esterification of alcohols in the presence of acyl-CoA by the enzyme alcohol acyl-transferase (AAT), are among the most important constituents of a strawberry aroma and are largely responsible for the sweet smell associated with strawberries. By detecting the esters in the headspace above strawberries by PTR-MS, a correlation was found between the expression of an AAT gene, total AAT activity, and the presence of esters. The PTR-MS data presented in this work represented a subset of a major data set collected over a 3-year period (2002-2004) to characterize the fruit quality of strawberry genotypes in northern Italy. 

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