In a first article in a previous issue of this journal, we considered the CDS/NPOS formalism, which was devised for the description of food colloids and also for description of the spatial organization of such matter in dishes. Here this formalism is applied to the description of the classical French sauces. It is also shown how this formalism is useful for the introduction of new dishes. Finally we consider how “comparative molecular gastronomy” could be achieved, giving one tool for the quantitative determination of the “robustness” of culinary recipes.
We identified the aroma components of fresh and dried thyme (Thymus vulgarlis L.) and also investigated the influence on aroma components of the packing method used during cold storage. A GC-MS analysis revealed that the fresh thyme aroma contained 14 components. A GC-O analysis indicated, α-pinene, linalool and borneol, which is a sweet smell like lavender and peculiar to mushrooms, to be distinctive in dried thyme. Cold storage reduced the fresh aroma components in thyme. There was little difference in the aroma components after cold storage between close-packed and vacuum-packed thyme. According to the GC-O analysis, α-pinene, which is the aroma of green leaves, and the sweet smell of linalool both retained a high odor level after cold storage.
This study clarifies the effect of vinegar addition on the salty taste of three kinds of soup stock: consommé, chicken, and bonito. The salty taste was examined with a sensory evaluation by panelists who were female students in their twenties. The panelists could significantly distinguish the salt concentration differences of the three kinds of stock between 0.8% and 0.7%, and also between 0.9% and 0.8%. But they could not significantly distinguish the differences, when 0.005-0.02% of acid concentration of vinegar had been added to the lower salt concentration stock. This result indicates the salt-reducing effect of vinegar on each of the three kinds of stock. Although there was no definite difference in the salt-reducing effect between rice vinegar and brown rice vinegar, it suggested that there were desirable kinds of vinegar suited for each stock taste.
The threshold values for dilute vinegar, salt, and mixed salt and vinegar solutions were studied by a sensory evaluation panel comprising female college students in their twenties. Although three kinds of vinegar solution converted into acetic acid concentration showed no significant difference in detection value, there was significant difference in the recognition value. The addition of salt at half the concentration of each person’s detection threshold value significantly lowered the detection threshold value for the vinegar solutions, but did not significantly affect the recognition threshold value for the vinegar solutions. The addition of vinegar at half the concentration of each person’s detection threshold value significantly lowered both the detection and recognition threshold values of the salt solutions. These results indicate that a low level of sourness strengthened the salty taste with a very low salt concentration.
The effects of the concentration and heating temperature of collagen-peptide from pig skin (CP) on the mechanical and thermal properties of agar gel (AG) were studied by measuring the rupture properties, dynamic viscoelasticity, and differential scanning calorimetry (DSC). The frequency dependence of G′ and G″ of a 50 w/w% CP solution showed that it behaved as a liquid even when cooled to 10°C. The rupture strain, stress and storage modulus of the AG-CP gel decreased with increasing CP concentration >20 w/w%. AG (5 w/w%) showed an endothermic peak at 78.8°C by heating DSC, and an exothermic peak at 32.5°C by cooling DSC. A solution of CP (30 w/w%) showed an endothermic peak at 20.2°C and an exothermic peak at 10.0°C. Mixtures of AG (5 w/w%) and CP (10~40 w/w%) showed two endothermic peaks, while AG (5 w/w%) and CP (50 w/w%) showed one endothermic peak. It is suggested that CP inhibited the gelation of AG. The molecular weight of CP was unchanged by heating at 60°C and 90°C, although the storage modulus and rupture strain of the AG-CP gel at 90°C were a little larger than the values 60°C.
Rice noodles were produced in order to expand the use of Japonica rice and to promote its consumption. To unpolished rice noodles was then added tamarind to improve the texture and preservation. Mechanical measurements were conducted by a Rheoner and the noodles tested by a sensory evaluation. The water retentivity of the noodles with added tamarind was higher than that of the unpolished rice noodles. Consequently, the hardness of the noodles was slightly changed by adding tamarind. There was no difference in hardness between the cryopreserved noodles and non-frozen noodles by adding tamarind. The radical scavenging activity of the noodles with added tamarind was higher than that of the unpolished rice noodles. The sensory evaluation disclosed no significant difference between the preference for the unpolished rice noodles and the noodles with added tamarind. The texture, preservation, and functionality of rice noodles could be improved by adding tamarind.
The quality and palatability of the F1 genotype of high-sugar-content tomato (Amashizuku) and common tomato (Reiyo) cultivated under the same standard conditions were compared with high-suger-content Amera tomato. The Brix value of Amashizuku cultivated under the same conditions as Reiyo was almost the same as that of Amera. Although Amashizuku and Amera contained more glucose and fructose than Reiyo, Amashizuku had a higher ratio of glucose to fructose than Amera, and the sweetness quality of Amera was different from that of Amashizuku. The acidity of the jelly part of Amashizuku was significantly higher, although there was no significant difference in the acidity of the flesh. The hardness was highest in the flesh with pericarp of Amashizuku, while it was highest in the flesh of Amera without pericarp. A sensory evaluation showed that Amashizuku and Amera were significantly preferred over Reiyo.
It is important to make vegetables enjoyable to eat in order to increase their consumption. Our preliminary experiment showed the possibility that steaming carrot made it sweeter. Organoleptic evaluations and physicochemical experiments were conducted on carrot slices subjected to various steaming times. Longer steaming time increased the sensory softness, juiciness and sweetness. It was not possible to explain the sweetness caused by steaming as being dependent on the sugar content of the carrot slices, because the sugar content remained unchanged by the steaming treatment. The amount of extract exuded from the steamed slices when pressing at a constant low pressure for 30 s was compared. The amount of extract increased with increasing steaming time. Moreover the extract contained about 10% sugars. We consider that the amount of the extract that was easily exuded was related to the evaluated sweetness and juiciness.