2025 Volume 51 Issue 4 Pages 96-102
By pressurized hot water treatment, total polyphenols, hydroxytyrosol and tyrosol were extracted from olive pomace, and the agricultural use of the extraction residue was examined. As a result of extracting components with a batch-type reactor with a volume of 500 mL, the total polyphenols, hydroxytyrosol and tyrosol were extracted under the condition that the reaction temperature was 20–280°C, the reaction time was 30 min, and the amount of extraction of each component increased markedly when it exceeded 160°C. The recovery rate of each component was almost 100% for total polyphenols, 84% for hydroxytyrosols and 63% for tyrosols. As a result of treatment with a batch-type reactor with a volume of 3.2 L, the extraction amount and recovery rate of each component increased from that of a reactor with a volume of 500 mL, and the tendency to produce unknown components was similar. The amount of extraction of each component is large, and the processing temperature of 240°C was considered optimal as a condition to minimize the influence of unknown components. Komatsuna (Japanese Mustard Spinach, Scientific Name: Brassica rapa L. cv. Rakuten) was developed using the extraction residue from pressurized hot water treatment at the condition (reaction temperature of 240°C and a reaction time of 30 min). In the condition that the mixing rate of the dry powder of the extraction residue is less than 1%, Komatsuna is grown as the chemical fertilizer zone.
