Kabosu

Kabosu is used green for its juice in Oita dishes and as a condiment; the Oita association also describes a regional availability calendar. Elizabeth Andoh describes its juice, skin and pith as culinary ingredients and gives an approximate fruit weight of 55 g with a grapefruit-orange flavor and slight lime-like bitterness. Individual video samples have been described as mildly herbal or lemon–mandarin-like. These are regional-use and general sensory accounts, not measurements of every Kabosu fruit.^{⁠[8]⁠[9]⁠[5]⁠[11]⁠[12]}

At Riverside, California, the UCR account reports Kabosu fruit evaluations from 2003 through 2007; its narrative describes formal evaluations in September and October, while the accompanying table includes September–November samples. Across those records, mean fruit weight was 71.2 g, juice content 28.2%, and acidity 3.2% citric acid. The report also describes rounded fruit averaging 5.3 cm wide by 5.2 cm high, with a pebbly rind averaging 4.2 mm thick and 17.2 seeds per fruit. These values describe the reported Riverside sample set.^⁠[1]

UCR describes Kabosu trees as dense and spreading, with moderate vigor, elliptical leaves and medium-winged petioles. Its account reports 20-year-old trees about 10 feet tall on Carrizo and C-35 citrange rootstocks without observed incompatibility; this is a rootstock-specific observation. The Oita association gives August–October as the regional season for best juice quality and quantity; storage and greenhouse production extend availability. UCR reports that tristeza in the original import was eliminated by thermotherapy; this is accession history, not a resistance claim.^⁠[1]⁠[8]

Kabosu’s origin and parentage remain unresolved. The Oita association presents the Sogen story as a legend, while UCR records competing accounts involving an Oita chance seedling, a spontaneous Yuzu mutation and an uncertain papeda–sour-orange parentage. Todolí likewise lists competing origin hypotheses. A separate DNA-marker study identifies a Kunenbo-A seed-parent × Yuzu pollen-parent result for accession A047; the study does not establish that pedigree for every plant called Kabosu or link A047 to UCR accession CRC 3943. The catalog’s existing generic parentage and ancestry proportions remain unverified.^{⁠[8]⁠[1]⁠[10]⁠[3]}