The aim of the present study was to investigate the quality characteristics of the aronia cultivar ‘Viking’ as affected by cultivation region. Aronia cultivated in 5 different regions (Danyang, Geochang, Gangjin, Gochang, and Ganghwa) was collected. pH, total acid, soluble solid, redness, total anthocyanin, total polyphenol, tannin, and organic acids were analyzed. Correlation analysis was also performed to determine the relationship between the quality characteristics of aronia and meteorological factors in each cultivation region. All variable assessed differed significantly among samples. pH ranged between 3.86-4.06. The highest pH was recorded in aronia cultivated in Gochang. Aronia grown in Ganghwa had the highest total acid, soluble solid, and total anthocyanin content and the highest redness. Malic acid, tartaric acid, and citric acid were detected in all aronia samples, with malic acid being the predominant organic acid in the aronia cultivars. Correlation analysis revealed pH and soluble solid content to have significant positive correlations with sunshine duration. However, redness showed a significant negative correlation with precipitation. Therefore, it can be confirmed that cultivation region play an important role in determining the quality characteristics of aronia ‘Viking’ from the results of this study.

Aspergillus luchuensis 34-1 was inoculated into wheat pellets with different conditions of raw materials to produce nuruk. The degree of substrate reactivity improvement of steam treated raw materials compared with that of non-heat treated was analyzed. The water content of the pellet was adjusted to 25% and 35%, and steam treatment for 10 minutes improved the substrate reactivity at 2.1-fold and 3.1-fold, and sterilization was also possible. The characteristics of improvement pellet nuruk were investigated according to the degree of crushing and water content of raw materials according to the temperatures and humidities (23°C, 30°C and RH 60%, RH 80%). The pH of the pellet nuruk was higher depending on the temperature, humidity and moisture content of the koji were lower, and the pH of the flour-pellet nuruk was lower than that of 2 mm milling wheat-pellet nuruk according to milling degree. It can be seen that the milling degree affects the growth of mold. The acidity and amino acid were generally higher as fermentation time increased. Also, the higher the incubation temperature, humidity and moisture content, the higher the value. Glucoamylase activity was significantly the highest in moisture content 35% D2b nuruk, cultured at 30 °C and 80% RH for 38 hours. This is higher than the previous reports on glucoamylase of rice-koji or commercial nuruk using fungi isolated from traditional nuruk. From these study, it is expected that making of improvement pellet nuruk would save the fermentation time considerably compared with traditional nuruks.

Aspergillus oryzae 83-10 (AO) was inoculated in a wheat pellet with different concentrations of raw materials to produce Nuruk. The sterilized raw material (S) was found to be stable in the production of pellet-Nuruk and was suitable for the production of high enzyme power; high enzyme activity was obtained after fermentation for 32 h. The characteristics of pellet-Nuruk were investigated and the brewing characteristics were compared with those of the commercial SongHak (SH) Nuruk. The enzyme activities (dry base, unit/g) of S-AO (sterilized material and inoculated with A. oryzae) pellet-Nuruk (32 h culture) and the commercial SH Nuruk were compared. The activities of glucoamylase, α-amylase, and acidic carboxypeptidase were significantly higher in S-AO Nuruk. In terms of brewing characteristics, the soluble solid (°Brix) and total acid (%) were significantly higher in the SH mesh, and the amino acid content and alcohol content (%) were significantly higher in the S-AO mesh. The amount of Nuruk added for yakju fermentation was set at 30 unit/g × g of rice weight based on the glucoamylase activity. The enzymatic activity immediately after preparation was 26.69 unit/mL and 17.58 unit/mL for S-AO and SH, respectively. Based on these results, preparing pellet-type Nuruk should considerably save fermentation time compared with traditional Nuruk products.