NIR-FT Raman and FT-IR spectra of the crystallized 2,6-bis (p-N,N-dimethyl benzylidene)cyclohexanone (C 24 H 28 N 2 O) have been recorded in the region 3200-500 and 4000-400 cm −1 , respectively. The spectral interpretation has been done following full structure optimization and vibrational wavenumber calculations based on the density functional theory (DFT) using the standard B3LYP/6-31G * basis set. The predicted vibrational spectra are in excellent agreement with the experiment, permitting an unambiguous assignment for the unusual downshifting of nC O caused by expanded conjugation effects in the dienone system. The optimized geometry clearly demonstrates the 'half-chair' conformation of the central nonheterocyclic ring. The ring C-H stretching vibrational modes involving aromatic hydrogen atoms participating in steric interaction have been observed with low intensities. There are valid structural and spectral bases for the enhancement of its bioactivity due to full charge transfer reaction by the substitution of the electron-donating 4-dimethylamino group into the aryl rings. The existence of intramolecular, C-H ... O, improper, blue-shifted hydrogen bond was investigated by means of the natural bonding orbitals (NBO) analysis. There are also slight dissimilarities in the bond lengths and endocyclic bond angles of both phenyl rings due to the effect of the heavy substitution. The characteristic ring modes have also been assigned in detail.

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Non-waxy and waxy rice starches adjusted to 20% moisture (wet based, w.b.) were heated in a differential scanning calorimeter to determine the optimum parameters for producing slowly digestible starch (SDS). Starches heated to the temperature of melting (T m ) and held for 60 min in the calorimeter showed a slow digestibility compared to unheated samples. Digestibility decreased by 25 and 10%, respectively, for non-waxy and waxy rice starches relative to non-treated starches. Heat-moisture treatment of waxy corn, non-waxy corn and wheat starches at the T m determined for non-waxy rice starch did not result in significant decreases in digestibility. For waxy rice starches heat-treated in microwave or conventional ovens at the T m , there were slight but significant increases in digestibility of the treated starches compared to non-treated starches at all incubation times. Digestibility was higher for starches heated for 30 min than for 60 min. Non-waxy rice starches did not show any significant changes in digestibility. Heat-moisture treatment at the T m and the holding time of sample at that temperature in a differential scanning calorimeter were found to be significant to the formation of slowly digestible heat-moisture treated starch.

Raw, freshly cooked, stored and recooked beef muscle samples were assessed by chemical, instrumental and sensory methods of analyses for flavor quality, with particular emphasis on warmed-over flavor (WOF). The character notes used by a trained sensory panel to describe WOF were cardboardy, rancid, stale, and metallic. Samples analyzed by direct gas chromatography utilizing either packed or fused silica capillary columns showed that compounds usually associated with lipid oxidation reactions could be used as marker compounds to follow the development of WOF. Of the many compounds that appeared to be markers, hexanal and 2,3-octanedione as well as total volatiles showed a highly significant degree of correlation when compared to sensory scores and 2-thiobar bituric acid (TBA) numbers. Many of the volatile compounds that were identified in WOF meat samples were also found in the distillates prepared for the TBA reaction.

Correlation of elements contributing to meat flavor quality (MFQ) were examined. Muscle structure influences generation of micro temperature environments that lead to formation of flavor-zones. Generation of such zones was also attributed to a structurally-dependent barrier to oxygen. MFQ was examined in the presence and absence of oxygen. Vacuum storage completely retarded flavor deterioration as marked by chemical markers such as thiobarbituric acid reactive substances and lipid volatiles. Vacuum storage incompletely affected changes in sensory attributes; it partially retarded development of painty, cardboard, bitter and sour flavors and limited loss of desirable flavors such as cooked beeflbrothy and browned/caramel. Bivariate plots of factor solutions resulting from multivariate principal components analysis proved a suitable method to graphically present statistical correlations between experimental treatments and sensory, chemical, and instrumental attributes.