The Effect of One-Year Fermentation of Fruit () Sugar Syrup on Amygdalin Level: A Natural Toxic Compound.

() is an economically important fruit in Korea. Recently, public interest in sugar syrup is increasing. However, the presence of toxic amygdalin in the fruit syrup is a concern. Thus, the current investigation aimed to observe effects of maturity, ripening methods, processing, and fermentation period on the amygdalin level in sugar syrup. Six different types of sugar syrup were prepared and amygdalin content was monitored at 3-month intervals. Higher levels (>63 mg/L) of amygdalin were found in syrups prepared from unripe fruit compared to those in syrups made from ripe fruit after 3 months of fermentation. A rapid reduction in amygdalin content was observed until 9 months in all syrups, gradually reducing to <5 mg/L at 12 months. More than 9 months of maturation is crucial for reducing the amygdalin content sugar syrup, regardless of fruit maturity, source of fruit, and processing method.