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Flavor Development during Cocoa Roasting
Published in Hii Ching Lik, Borém Flávio Meira, Drying and Roasting of Cocoa and Coffee, 2019
Some key odorants are found to be already present in unroasted cocoa. This may arise from compounds in the cocoa pulp or formed during the fermentation process. A recent report showed that cocoa pulps have a variety of flavor and aroma traits such as soursop, mango/rose, banana, jasmine, citrus and anona (Eskes et al., 2017). Chocolate made with cocoa beans with a banana pulp flavor showed a strong and persistent cooked banana/banana jam flavor. Unroasted Criollo cocoa beans contain compounds such as 2- and 3-methylbutanoic acid, 2-phenylethanol, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 2-methyl-3-(dithio)-furan and phenylacetic acid (Table 4.1) (Frauendorfer and Schieberle, 2008). During the fermentation and drying of Forastero cocoa beans, 39 volatile chemical compounds were identified (Rodriguez-Campos et al., 2011). The volatile compounds comprised of aldehydes and ketones (8), alcohols (9), esters (11), acids (10) and pyrazines (1). The ratio of aldehydes to amyl alcohols and acetates to amyl alcohols can be used as an indicator for the degree of fermentation.
Contaminant Characteristics
Published in Stephen S. Olin, Exposure to Contaminants in Drinking Water, 2020
David A. Reckhow, Stephen S. Olin
An extensive list of C3 to C10 haloacids have been isolated as chlorination byproducts. Dichlorosuccinic acid may be the most prevalent halogenated byproduct, containing more than three carbon atoms (Christman et al., 1980). Among the unsaturated chlorinated acids, MX (which at acid pH exists mainly as its lactone, 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone) is a potent mutagen and animal carcinogen that is frequently detected at low levels (<0.01 μg/L) in chlorinated waters (Komulainen et al., 1997; Melnick et al., 1997).
Physical Constants of Organic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
6-Heptenoic acid 1-Hepten-4-ol trans-2-Hepten-1-ol Heptyl acetate Heptylamine Heptylbenzene Heptyl butanoate Heptylcyclohexane Heptylcyclopentane 5-Heptyldihydro-2(3H)furanone Heptyl formate 4-Hydroxyundecanoic acid lactone 1-Heptanamine
The bioactive properties and quality attributes of Chrysanthemum morifolium Ramat as affected by pulsed vacuum drying
Published in Drying Technology, 2022
Dongyu Sun, Min Wu, Huihuang Xu, Nan Shang, Fei Gao, Yong Wang, Zhian Zheng
According to the principal components analysis (PCA), about 80.83% variation and origin information were recognized (PC1 = 52.36%, PC2 = 18.83%, and PC3 = 9.64%). As shown in the Figure 3, the aroma component of FD sample was significantly different from others exhibited a prominent positive contribution to PC1 and PVD samples were distributed on the left side of the score plot. Most of the PVD samples were showed as the energetic factors to PC2 except samples prepared with 70 °C, 80 °C and 5 min VD times, which was mainly due to the production of the positive components during PVD drying process including propanal, 2-methyl-(C2), 3-buten-2-ol, 2-methyl-(C5), butanal, 2-methyl-(C8), 1,4-cyclohexadiene, 1-methyl-(C11), 1,3-cyclopentadiene, 5-(1,1-dimethylethyl)-(C13), 1,3-cyclopentadiene, 1,2,5,5-tetramethyl-(C14), 5-hepten-2-one, 6-methyl-(C17), acetic acid, methyl ester (C20), 2,3-pentanedione (C21), 3(2H)-furanone, dihydro-2-methyl-(C24), 1,3,3-trimethylcyclohex-1-ene-4-carboxaldehyde, (+,−)-(C25), acetic acid (C26), furan, 3-methyl-(C27) and toluene (C28). In addition, it can be seen with the PR decreased, the contribution of aroma component to PC2 increased, indicated that the rapid pressure change in drying chamber is not conducive to the retention of aroma components. Moreover, under the same PR, the positive effect of PVD dried sample on PC2 diminished with temperature enhanced, this can be due to the deterioration of the volatile components at high temperatures.
Comparison of the slow, fast, and flash pyrolysis of recycled maize-cob biomass waste, box-benhken process optimization and characterization studies for the thermal fast pyrolysis production of bio-energy
Published in Chemical Engineering Communications, 2022
B. O. Adelawon, G. K. Latinwo, B. E. Eboibi, O. O. Agbede, S. E. Agarry
In general, the biomass-derived bio-oil compositions varies widely. For example, the bio-oil derived from yellow and white corn cobs by Ogunjobi and Lajide (2013) also contained 16 and 13 chemical compounds which consisted of 2-Methyl-2-cyclo pentenone, 3-Methyl-1, 2-cyclopentanedione, phenol, 4-Ethyl phenol, guaiacol, 2, 6-Dimethoxy phenol, and 2-Methoxy-4-ethyl phenol. Acetic acid, levoglucosan, and phenols accounted for a large proportion in the bio-oil from pistachio shell pyrolysis (Açikalin et al. 2012). Bio-oil from maize stalk pyrolysis is a complex mixture of organic compounds with the major compounds found being acetic acid, 1-hydroxy-2-propanone, 2.3-dihydro-benzofuran, phenols, 3-methyl-1.2-cyclopentanedione, 1-(acetyloxy)-2-propanone, 2.3-dimethyl-cyclopenten-1-one, furfural, 2(5H)-furanone, and levoglucosan (Ali et al. 2016). Bio-oil from grape seeds pyrolysis was mainly composed of phenol, 2-furanmethanol, 2-methoxyphenol, 4-ethyl-2-methoxyphenol, 2-methoxy-4propylphenol, 2-ethylphenol, and n-hexadecanoic acid, (Z)-13-docosenamide, octadecanamide decane, tridecane, tetradecane, and pentadecane (Alper et al. 2015). These varying observed organic compounds components in bio-oil clearly revealed that the compositions of bio-oils depend on the raw feedstock compositions or characteristics as well as on the pyrolysis process conditions (Ngo et al. 2013).
Green synthesis, characterization and antimicrobial activity of zinc oxide nanoparticles using Artemisia pallens plant extract
Published in Inorganic and Nano-Metal Chemistry, 2021
The band in IR spectrum at 2970 cm−1, as shown in Fig 2(a), corresponds to asymmetric C-H stretching and a small sharp peak observed at 1641 cm−1 attributed to the presence of aromatic ring. The peak at 1628 cm−1 present in Artemisia pallens plant extract spectrum indicates the presence of ketone derivatives and can also be confirmed with the presence of 5-hepten-3-one with retention time of 17.12 min and molecular ion and base peak at m/z = 236 and m/z = 111 respectively, as given in GC-MS data (Table 1). Other ketonic derivatives given in GC-MS data are 5,5-dimethyl-2(5H)-furanone with retention time of 6.642 and molecular ion and base peak at m/z = 112 and m/z = 97.05 respectively, and ethanone with retention time of 11.45 min and molecular ion and base peak at m/z = 125 and m/z = 43 respectively. Absorption peak at 2311 cm−1 as seen from IR spectrum of Figure 2a may be due to atmospheric carbon dioxide impurity.