Can I boil and sterilize the glass jar in boiling water before making fruit syrup?

When making pickles or homemade syrup, many people boil and sterilize storage containers in boiling water. Ishizuka Glass's Metal Cap Container glass storage jar is not a product made of heat-resistant glass ^[1]. When ordinary glass experiences sudden temperature changes, there is a high risk of cracking or breaking due to the difference in shrinkage and expansion between the inside and outside. Therefore, boiling water sterilization—such as placing it in a pot with water to boil or suddenly pouring hot water into it—is not possible ^[2].

If sterilization is necessary, you must choose another method instead of heat. The basic method is to wash it cleanly by dissolving neutral detergent in lukewarm water and drying the moisture completely. If you wish to sterilize it for hygiene, soaking a dry cloth in high-proof soju or food-grade ethanol and wiping the inside evenly is widely used. After washing, you must completely air out the internal moisture in a well-ventilated area to safely store contents without spoilage.