Comparison of Odor-Active Compounds from Six Distinctly Different Rice Flavor Types

Abstract

Using a dynamic headspace system with Tenax trap, GC-MS, GC-olfactometry (GC-O), and multivariate analysis, the aroma chemistry of six distinctly different rice flavor types (basmati, jasmine, two Korean japonica cultivars, black rice, and a nonaromatic rice) was analyzed. A total of 36 odorants from cooked samples were characterized by trained assessors. Twenty-five odorants had an intermediate or greater intensity (odor intensity >or= 3) and were considered to be major odor-active compounds. Their odor thresholds in air were determined using GC-O. 2-Acetyl-1-pyrroline (2-AP) had the lowest odor threshold (0.02 ng/L) followed by 11 aldehydes (ranging from 0.09 to 3.1 ng/L), guaiacol (1.5 ng/L), and 1-octen-3-ol (2.7 ng/L). On the basis of odor thresholds and odor activity values (OAVs), the importance of each major odor-active compound was assessed. OAVs for 2-AP, hexanal, ( E)-2-nonenal, octanal, heptanal, and nonanal comprised >97% of the relative proportion of OAVs from each rice flavor type, even though the relative proportion varied among samples. Thirteen odor-active compounds [2-AP, hexanal, ( E)-2-nonenal, octanal, heptanal, nonanal, 1-octen-3-ol, ( E)-2-octenal, ( E, E)-2,4-nonadienal, 2-heptanone, ( E, E)-2,4-decadienal, decanal, and guaiacol] among the six flavor types were the primary compounds explaining the differences in aroma. Multivariate analysis demonstrated that the individual rice flavor types could be separated and characterized using these compounds, which may be of potential use in rice-breeding programs focusing on flavor.

Effects of Adding Unsaturated Fatty Acids on Fatty Acid Composition of Saccharomyces cerevisiae and Major Volatile Compounds in Wine

“…As shown in Table 4, 16 aroma compounds had an OAV above 1 in our study. According to previous research (Aznar et al, 2001;Buettner et al, 2003;Peinado et al, 2006;Li et al, 2008;Yang et al, 2008), these compounds are mainly associated with the attributes 'banana', 'apple', 'pear', 'strawberry', 'citrus' 'sweet', 'roses', 'fruity', 'fatty', 'cheese', 'rancid', 'nail polish', 'balsamic' and 'green' (Table 4). The OVAs of ethyl hexanoate (fruity, green apple, banana attributes) and ethyl decanoate (fruity attribute) in wine D were 6.15-and 3.62-fold higher than those of wine A.…”

Identification of aroma volatiles and understanding 2-acetyl-1-pyrroline biosynthetic mechanism in aromatic mung bean (Vigna radiata (L.) Wilczek)

“…(2E)-2-Decen-1-ol and 2-ethyl-1-dodecanol are first time reported in mung bean seeds, in which (2E)-2-decen-1-ol with Waxy type odor and 2-ethyl-1-dodecanol with citrus type odor were reported earlier in natural plant systems (Eyres et al 2005). Most of alcohol compounds were previously reported in rice (Buttery et al 1988(Buttery et al , 1999Yang et al 2008;Mathure et al 2014).…”

Karakteristik Flavor Beras Varietas Padi Aromatik dari Ketinggian Lokasi yang Berbeda

“…Komponen C2 memiliki nilai eigein 9,37%, disebut dimensi benzaldehyde yang mengintrepretasikan aroma seperti almond (Sik Yang et al 2008). Benzaldehyde merupakan golongan aldehid yang berperan besar dalam memberikan aroma pada nasi (beras aromatik).…”

“…Benzaldehyde merupakan golongan aldehid yang berperan besar dalam memberikan aroma pada nasi (beras aromatik). Benzaldehyde merupakan salah satu senyawa selain 2AP yang merupakan penanda antara beras aromatik dan nonaromatik (Petrov et al 1996) (Sik Yang et al 2008).…”

“…Heptyl alcohol memiliki aroma green (Sik Yang et al 2008). Komponen-komponen yang berkorelasi positif pada C5 adalah isoamil alcohol dan 1-hexene,3,5-dimethyl dan berkorelasi negatif dengan senyawa 2-hexanone,5-methyl, isopropil alcohol, pentanoic acid, methyl ester, dan methyl 2-furoate.…”