Changes in the quality of kimchi with added prickly pear cactus (Opuntia ficus-indica var. saboten) extracts during fermentation

The effects of the addition of prickly pear cactus (Opuntia ficusindica var. saboten) extract (0, 0.4, 0.8 and 1.2%) on pH, titratable acidity, lactic acid bacteria, total bacterial populations, texture and sensory qualities of cabbage kimchi were studied to establish an optimum recipe. The total phenol content of the prickly pear cactus extract was 1 759.0 mg·kg¹. Upon the addition of prickly pear cactus extract, the pH increased compared to that of kimchi without the extract after 36 days, and the titratable acidity also increased with the addition of prickly pear cactus extract. During the fermentation period, the degree of salinity decreased with the addition of the extract, and the cutting and compression forces were higher during the fermentation period. The prickly pear cactus extract also inhibited total bacterial and lactic acid bacterial growths during fermentation. The 0.8% addition of extract improved the sensory quality (overall taste) of kimchi. Therefore, the addition rate of prickly pear cactus extract was determined to be 0.8%, and the sensory quality, such as the taste of a treated sample, could be maintained high during fermentation.