Asimina triloba (L.) Dunal - syn. Annona pendula Salisb.; Annona triloba L. - Annonaceae
pawpaw, Indian banana, dog banana, Papau, Indianerbanane, Dreilappiger Flaschenbaum
Small deciduous tree, up to 1om high, native to North America, also cultivated; leaves alternately, obovate-oblong, glabrous, base cuneate base, tip acute tip, prominent midrib, 15-30cm long and 10-15cm wide; flowers emerge before leaves; pendant on nodding, sturdy, pubescent peduncles up to 4cm long, petals maroon-colored, three-lobed, with fetid aroma; fruits oblong-cylindric berries, 3-15cm long, 3-10 cm wide, weight 200-400g, borne singly or in clusters that resemble the “hands” of a banana plant.
[Layne, Desmond R. „The pawpaw [Asimina triloba (L.) Dunal]: A new fruit crop for Kentucky and the United States.“ HortScience 31.5 (1996): 777-784] http://hortsci.ashspublications.org/content/31/5/777.full.pdf
„It was introduced to Japan in the 19th century but was not accepted and developed as a commercial fruit-bearing tree. One reason is that the fruit had much too strong flavor for Japanese tastes… The aroma of pawpaw fruit is very powerful and reminescent of the mixture of pineapple, bread, and butter…
Volatile components of pawpaw (Asimina triloba Dunal.) fruit were mainly ethyl esters (hexanoate, 50.2%; octanoate, 19.3%; butanoate, 8.5%; and decanoate, 1.3%) which were accompanied by methyl esters (butanoate, hexanoate, octanoate, geranate, decanoate, and farnesate). Butane-2,3-diol monoesters (butanoate, hexanoate, and octanoate) and 3-hydroxybutan-2-one (acetoin) esters (acetate, butanoate, hexanoate, and octanoate) were also detected, and these esters except 3-acetoxybutan-2-one were reported to be present in nature for the first time.“
[Shiota, Haruyasu. „Volatile components of pawpaw fruit (Asimina triloba Dunal).“ Journal of Agricultural and Food Chemistry 39.9 (1991): 1631-1635]
„Ripe fruit from four pawpaw cultivars (Asimina triloba) were analyzed for headspace volatiles and sensory properties. The volatile components of pawpaws were found to be mainly ethyl and methyl esters of fatty acids. Ethyl hexanoate was found to be in the highest concentration (31-65%) in fruit from all cultivars. Other esters found in substantial quantities were ethyl butanoate (3-11%), methyl hexanoate (1-4%), methyl octanoate (2-5%) and ethyl octanoate (4-31%). Fruit from the cultivar containing the highest total volatile concentration (101.8 ppm) and the highest ethyl hexanoate content (65%) had the highest tropical fruit-like aroma intensity.“
[McGrath, Marilyn J., and Carol Karahadian. „Evaluation of headspace volatiles and sensory characteristics of ripe pawpaws (Asimina triloba) from selected cultivars.“ Food chemistry 51.3 (1994): 255-262]
„The odors of A. triloba and baker’s yeast Saccharomyces cerevisiae shared ethanol, ethyl acetate, acetic acid, and other compounds but differed in relative amounts of 3-methyl-1-butanol, 3-OH-2-butanone, and butane-2,3-diol. Immature green flowers of A. triloba produced sesquiterpenes common to the foliage of many plants. In contrast, sexually mature flowers emitted fermentation volatiles, with additional nitrogenous compounds (androgynoecium) and butanediols (outer corolla) emitted by male flowers… Emission rates were fourfold greater in male than female flowers during the day but were comparable at night, perhaps because of overlapping gender expression. The yeasty odor of A.triloba is unusual in angiosperms and may serve to attract novel fly and beetle pollinators…
The floral scent of green, immature flowers of A.triloba was dominated by γ-terpinene (11.7%) and (E)-β-caryophyllene (49.5%), female-stage flowers produced distinctive fermentation volatiles (e.g., ethyl acetate, ethanol, acetic acid) and were dominated by 3-OH-2-butanone (also known as acetoin), which contributed 77.9% of the relative peak area…Female- and male-stage flowers emitted the same absolute amounts of acetoin (not shown), but this compound’s relative contribution to male-stage odor (58.4%) was diminished by the addition of the butanediols and nitrogenous compounds.“
Nitrogen compounds of the male-stage odor included 2-methyl butane nitrile, 3-methyl butane nitrile, nitro-2-methyl butane, nitro-3-methyl butane, 2-methyl butyraldoxime, and 3-methyl butyraldoxime.
[Goodrich, Katherine R., et al. „When flowers smell fermented: the chemistry and ontogeny of yeasty floral scent in pawpaw (Asimina triloba: Annonaceae).“ International Journal of Plant Sciences 167.1 (2006): 33-46]
Asimina triloba (L.) Dunal as Annona triloba L.
Trew, C.J., Ehret, G.D., Plantae selectae, vol.1 t.5 (1750) [G.D.Ehret]
Asimina triloba, Botanischer Garten der Universität Wien
© Rolf Marschner (2017), www.botanische-spaziergaenge.at