Chemical structure caramel

Melanoidins (36, 48-50) are different from melanins, humins, and caramels, but similar to humus (37), according to Maillard (4, 1 1, 19-21). Kato and Tsuchida (51) studied the possible chemical structure of melanoidins. 

The nonvolatile, high-molecular-weight fraction of caramel produced without any catalyst seems to contain three components. They are called caramelan, caramelen, and caramelin. Thus far, the problem of their chemical structure remains an intriguing, unsolved part of the chemistry of caramel. 

Lactose (98% of purity) was supplied from Fluka, octa-O-acetyl-lactose was synthesized for the purpose of this paper[ ]. The chemical structures of both investigated saccharides are presented in Fig 1. In order to avoid caramellization of lactose (this disaccharide caramelizes relatively easy) the sample was heated very quickly to its melting point and when whole sample was molten it was supercooled very quickly. Isobaric dielectric measurements at ambient pressure were carried out using a Novo-Control GMBH Alpha dielectric spectrometer (10 -10 Hz). The samples were placed between two stainless steel flat electrodes of the capacitor with gap 0.1 mm. The temperature was controlled by the Novo-Control Quattro system, with use a nitrogen-gas cryostat. Temperature stability of the samples was better than 0.1 K... 

Two important character-impact compounds of strawberry flavor are the ftiranones 2,5-dimethyl-4-hydroxy-2//-furan-3-one (FuraneoF ) and 2,5-dimethyl-4-methoxy-2/f-furan-3-one (mesifuran) (24). However, at various concentrations, FuraneoF can simulate other flavors, e.g., pineapple (11) or Muscadine grape (25) at low levels, and caramel at high levels. Mesifuran exhibits a sherry-like aroma and is a contributor to sherry and French white wine aroma. Other important character-impact compounds of strawberry flavor are methyl cin-namate and ethyl 3-methyl-3-phenylglycidate, a synthetic aroma chemical (4,26). Representative chemical structures for fruit flavor impact compounds are shown in Fig. 2. 

---