Raspberry odor threshold

The character impact compound is the raspberry ketone , i. e. l-(p-hydroxyphenyl)-3-butanone (Vn). Its concentration is 2mg/kg and its odor threshold is 5 pg/kg (water). The starting point for the biosynthesis of VII is the condensation reaction of p-cumaroyl-CoA with malonyl-CoA (cf. Formula 18.38). Additional aroma notes are provided by (Z)-3-hexenol, a- and P-ionone. 

In addition to the character impact compound of raspberry, 4-(4-hydroxy-phenyl)-butan-2-one (raspberry ketone), alpha- and beta-ionone, geraniol, and linalool were concluded to be of importance in raspberry aroma (30). Its odor threshold was measured at 1-10 ig/kg. The ionones have chemical stracture similarities and potencies comparable to P-damascenone (11). 

M. Larsen and L. Poll, Odor thresholds of some important aroma compounds in raspberries, Z. Lebensm. Unters. Forsch. 191 129 (1990). 

Several Ci 3-norisoprenoids, including p-damascenone, p-ionone, and 1,1,6-trimethyl-1,2-dihydronaphtalene (TON), are powerful odorant in wine. P-Damascenone, which can be present in young wine at up to 180 times its odour threshold of 0.05 (Jig/L, has a stewed apple, rose, honey aroma (Francis and Newton 2005). P-Ionone, which has violet, flower, and raspberry aroma, is typically present at higher concentration in red wines. TDN develops a kerosene-like odour in aged whites, particularly Riesling (Francis and Newton 2005). 

C13H20O, Mr 192.30, isomers of ionone which differ only in the position of the ring double bond (a-, /3-, Y-, S-, and c-damascone). The name damascones or rose ketones is derived from their occurrence in the essential oil of damask rose (Rosa damascena). a-D. bp. 77-80°C (0.13 Pa), [alg +487° (CHCI3) /5-D. bp. 52 °C (0.13 Pa). D. possess the common olfactory feature of a narcotic-herby odor of exotic flowers with an undertone resembling black currents. Although a- and /3-D. in rose oil have a combined content of merely ca. 0.15%, they determine the basic odor of the oil (olfactory threshold 0.009 ppb). D. occur in other flower oils as well as in tea, certain tobacco, and fruit aromas, e.g., apples and raspberries, a- and /3-D. are in-... 

CsHgOj, Mr 128.13 cryst., mp. 79-80 °C odor resembling caramel, in dilute solution pineapple- and straw-berry-like olfactory threshold in water 40 ppt. LD50 (rat p.o.) 1660mg/kg. An important flavor compound, occurring naturally in pineapples, strawberries, raspberries, etc., sometimes as the glucoside. It is also formed thermally from deoxyhexoses, e. g., in coffee. For production, see... 

P-Damascenone (343) is present in Bulgarian rose oil at a level of only 0.05%, but is a major contributor to the overall odor of the oil. Not surprisingly, it is used in reconstitutions of rose oil. It is also found in rose, apricot, beer, grape, mango, tomato, wine, rum, raspberries, passionfruit, and blackberries. Its detection threshold is one-tenth those of a- or p-damascone. 

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