Accumulation Of Aromatic Compounds Research Articles

Nutrient Composition and Flavor Profile of Crucian Carp Soup Utilizing Fish Residues through Comminution and Pressure-Conduction Treatment.

In conventional fish soup processing, valuable aquatic resources like fish skins, bones, and scales are often squandered. This study was aimed at investigating if comminution combined with pressure-conduction treatment has the potential to enhance the reutilization of cooking residues. The different blending ratios of original soup (OS), made from the initial cooking of fish, and residue soup (RS), produced from processed leftover fish parts, were alternatively investigated to satisfy the new product development. Comminution combined with pressure-conduction treatment significantly increased the nutrient contents of calcium, soluble proteins and total solids in crucian carp soup (p < 0.05). With the increase in RS ratio, the decomposition of inosine monophosphate (IMP) and free amino acids was accelerated, but the accumulation of aromatic compounds was promoted simultaneously. In addition, the Maillard reaction may lead to a reduction in aldehydes, causing a diminution in the characteristic flavor of fish soup, while the formation of 1-octen-3-ol can enhance the earthiness of the fish soup. The electronic tongue test results and the sensory results showed that the blend ratio of OS and RS at 7:3 had a more significant umami and fish aroma (p < 0.05). Under this condition, the mixed soup has better nutritional values and flavor characteristics.

Behavior of glycosylated aroma precursors in Microvine fruits after guaiacol foliar application

Previous field-grown experiments were carried out to study the effect of guaiacol spraying on the accumulation of aromatic compounds in grapevine fruits and their wines. It was shown that such treatments increase guaiacol glycoconjugates in leaves, shoots and fruits of Monastrell variety (Vitis vinifera), where there was a release of aglycone compounds during wine processing, modulating the final wine aromatic profile, not only in terms of guaiacol. However, it remains unstudied the effect on the glycosylated grape aroma precursors pool and the time of their maximum expression. Nowadays, it is possible to use a model vine known as Microvine (DRCF-Dwarf Rapid Cycling and Continuous Flowering) to perform original physiological studies on fruit development in controlled environments. Therefore, the aim of this work was to use the Microvine model to study the effect of guaiacol sprays in such fraction when applied at several fruit developmental stages. The applications were carried out from phenological stage BBCH 71 (fruit set: young fruits begin to swell, remains of flowers lost) to BBCH 85 (softening of berries), to reveal stage-specific responses of the accumulation of glycosylated aroma precursors at BBCH 89 (berries ripe for harvest). Here, it is showed that guaiacol is an elicitor of the accumulation of glycosylated aromatic compounds in the fruit, with a higher efficiency when applied during ripening stages. Especially significant was the geraniol accumulation increment which was fiftyfold higher than in control ones.

Assessment of postfire soils degradation dynamics: Stability and molecular composition of humic acids with use of spectroscopy methods

AbstractThe effect of wildfires on the soils of the south taiga and forest‐steppe environments of Central Russia (Histic Spodosols and Eutric Fluvic Arenosols) was investigated in terms of the content and quality of humic acids (HAs) using instrumental spectroscopic methods (solid‐state carbon‐13 nuclear magnetic resonance and electron spin resonance). The bulk elemental composition of HAs was not essentially altered in postfire soils; however, the organic matter of fire‐affected superficial soil layers was characterized by changes in the structural composition and biochemical activity levels. Solid‐state carbon‐13 nuclear magnetic resonance spectroscopy showed that there is an intensive increase in aromatic compounds in HA molecules in soil from both the south taiga and forest‐steppe environments. There is a pronounced and statistically significant decline of aliphatic chain content in response to exposure to fire. The free radicals content and the degree of molecular stabilization assessed with electron spin resonance showed an essential alteration of the HAs, expressed in the increase in the radical's portion, in postfire soils compared with that found in soils not exposed to fire. It was also shown that the accumulation of aromatic compounds indicates only apparent stabilization of HAs due to the loss of periphery alkylic carbon species, which was confirmed by destabilization of the molecules as illustrated by the increase of free radicals.

Caractères de l’accumulation flavonique dans les tissus des organes sécréteurs des bourgeons d’ Aesculus hippocastanum L.

Summary The flavonol aglycones excreted by Aesculus hippocastanum buds are found in great quantities in the glandular hairs and in much smaller concentrations in the parenchyme, while coumarins are specially abundant in the parenchyme. In Spring and in Automn an enzymatic activity, the first step of which is the deamination of phenylalanine, is detected in the hairs; at other periods the parenchyme is characterized by a PAL activity. The correlations between these different enzyme activities and the accumulation of aromatic compounds in the tissues (flavonol secretion and coumarins) are analysed at different stages of the annual secretion cycle. The function of the different tissues is discussed.