In vitro digestibility and protein digestibility corrected amino acid scores (PDCAAS) were investigated to verify the availability of protein in various Rhizopus oligosporus fermented products of domestic soybean (Glycine max L.) cultivars. Danbaegkong (DBK), Daepung (DP), Daewonkong (DWK), Saedanbaek (SDB), Seonyu (SY), and Cheongja4ho (CJ4) were used as raw samples, which were fermented using commercially available Rhizopus oligosporus for 48 h. All cultivars showed increased crude protein content after fermentation. The crude protein content of DBK and SDB was significantly higher than that of the other samples (55.12% in DBK and 54.22% in SDB) (p<0.001). CJ4 had the highest alanine content of 28.88 mg/g (p<0.001), and no significant difference in cysteine content was detected among the cultivars. In most of the fermented samples, the in vitro digestibility was 0.9 or higher, indicating high protein in the fermented samples. However, it is considered that restrictions on digestion are low. In DWK, the amino acid content and PDCAAS, which together indicate protein quality, were 0.917 and 0.855, respectively, confirming that it was the best cultivar to provide the raw material for fermentation. In conclusion Rhizopus oligosporus fermented soybean products can be considered a prospective source of protein with high utility value.

The purpose of this study was to investigate the Maillard reaction–related physicochemical properties of three maize varieties (Kwangpyeongok, Sinhwangok2ho and Gangdaok) after roasting them for different times (0, 15, 25, 40, and 55 minutes). The Maillard reaction is a non-enzymatic browning reaction involving reducing sugars and amino compounds. The content of reducing sugar, the causative agent of the Maillard reaction, decreased as roasting time increased. Gangdaok showed the lowest reducing sugar content of 1.04 mg/g after 55 minutes of roasting. In the elapsed roasting time, chromaticity ‘L’ and ‘b’ values decreased. At 55 minutes of roasting, wherein the Maillard reaction occurred most actively, Gangdaok showed the lowest ‘L’ value of 56.37 and the highest ‘a’ value of 7.60. Gangdaok had superior conditions for inducing the Maillard reaction compared to other varieties, and it is consider that 'flint–type', an endosperm characteristic, may have been the influencing agent. This study detected a total of 52 types of volatile aroma compounds (VACs), of which 28 were produced after roasting. Of the total VACs detected, 2-Formyl-5-methylfuran and 2-Furancarboxaldehyde accounted for 43.8~45.5% and have been confirmed to be the major VACs present in roasted maize. Most of the correlations between the Maillard reaction–related characteristics showed high correlation coefficients.

This study was conducted to secure basic information for corn processing by comparing the quality characteristics according to maize cultivars and kernel types (dent, intermediate, flint-like). As a result of analyzing 15 cultivars, a range of measurements were observed: 100-kernel weight, 22.89~35.63 g; moisture, 7.57~8.42%; crude protein, 8.46~11.45%; crude lipids, 3.26~4.83%; Hunter’s L-value, 83.70~86.79; a-value, 2.61~5.49; b-value, 22.01~28.15; and total carotenoids, 6.74~17.07 μg/g. Significance among the cultivars was shown in all quality characteristics (p<0.001), but the significance among the kernel types was found only in crude protein (p<0.005), crude fat (p<0.001), and Hunter’s L-value (p<0.05). The hardness of maize was decreased proportionally to the soaking time for all maize cultivars (p<0.001). In particular, with the same soaking time for different kernel types, the hardness difference was shown in the order of flint-like > dent ≒ intermediate. It was confirmed that the decrease in the hardness of flint-like kernel of close to that of hard-type starch was slowed compare dent and intermediate kernels. So it is expected the some characteristic of kernel types will contribute to the appropriate customized use of the developed cultivars.

Amniotic membrane stem cells are considered as a good alternative to embryonic stem cells, but their use in clinical studies is still not common. Here, exosomes from canine amniotic membrane mesenchymal stem cells (cAmMSCexo) were used for dog sperm cryopreservation. Upon cryopreserved straws using cryoprotectant containing 0, 0.5, 1, or 2 μg/mL of cAmMSC-exo were thawed, motility and membrane integrity were analyzed. However, results showed no significant differences between the groups. We concluded that cAmMSC-exo with lower than 2 µg/mL have no effects on sperm cryopreservation, and further studies to get higher concentrations of cAmMSC-exo should be conducted for clinical application.

The purpose of this study was to derive the conditions for manufacturing rice porridge with optimum properties after reheating. The characteristics of rice porridge according to the soaking time, water addition rate, heating temperature, heating time, and cooling conditions were compared using the ‘Samkwang’ cultivar. In Step Ⅰ, as the heating temperature increased, the weight change decreased and the viscosity increased, and the temperature known as the main factor of the gelatinization also appeared to affect the viscosity increase. In Step Ⅱ, the viscosity and the texture properties was not significantly different as the soaking time was reduced, and 10 minutes was suitable because of due to the shortening effect of the total process time. In Step Ⅲ, the residual heat was lowered by cooling after the rice porridge production, so the viscosity could be greatly reduced. Also, it was confirmed that the water addition rate of 900% and the heating temperature of 15 minutes were optimal manufacturing conditions. The next study will investigate the porridge processability of rice cultivars using these results.

When producing rice products, it is very important to select suitable raw materials. Therefore, in this study, the quality characteristics of 16 rice cultivars were quantified to determine the criteria for evaluating the machinability of raw rice. The L value, which can affect the color of porridge prepared from rice, was the greatest for Hwaseonchalbyeo (84.17). The water-binding capacity, related to water interaction, was high in Hyangcheola (113.2%), and water solubility was high in Shingil (22.3%). Dodamssal (42.3%, 70.7 RVU) and Hwaseonchalbyeo (4.7%, 27.8 RVU) showed lower final viscosity compared to the cultivars in which the amylose content was medium groups (16.4~21.2%, 173.6~277.2 RVU). Specifically, cultivars with high or low amylose content had a low viscosity. The characteristics of the distribution of raw rice quality data were confirmed through 11 histograms. Furthermore, amylose content vs. water solubility, water solubility vs. peak viscosity, and peak viscosity vs. final viscosity showed high correlations (r=0.542, －0.569, and 0.836 respectively, p<0.01), and clear cultivar discrimination by the standard error of the mean (0.765~10.811). In conclusion, amylose content, water solubility, and peak viscosity were considered the most suitable characteristics for the quality evaluation of raw rice.