Why is spinach a bit bitter

The bitterness of spinach mainly comes from oxalic acid and natural bitter substances, which are related to the variety, growth environment, and cooking method. Spinach contains a high concentration of oxalic acid, which is one of the main sources of its bitter taste. Oxalic acid is a common organic acid in plants, distributed in both spinach leaves and stems, especially in old leaves where the content is higher. Oxalic acid can bind to taste buds receptors to produce a bitter taste perception, and may also form a slightly astringent taste. Different varieties of spinach have significant differences in oxalic acid content, and varieties with thick leaves often have more prominent bitterness. Insufficient light or excessive nitrogen fertilizer during the growth process can also promote the accumulation of oxalic acid. Some spinach varieties contain cucurbitacin compounds, which are natural phytochemicals with a distinct bitter taste. Spinach planted outdoors in spring may synthesize more defensive bitter substances due to the large temperature difference between day and night. Directly stir frying at high temperature without blanching during cooking can quickly release oxalic acid and bitter substances. When magnesium is lacking in the soil, spinach will compensate by increasing alkaloid synthesis and exacerbating bitterness. When the storage time is too long and the leaves slightly wilt, the juice released by cell rupture will also enhance the bitterness.

Choosing tender spinach leaves and blanching them quickly can effectively reduce bitterness. Adding a small amount of salt or cooking oil during blanching can help dissolve oxalic acid. Stir fry over high heat to preserve the sweet and refreshing taste, and pair with fresh ingredients such as minced garlic and mushrooms to neutralize bitterness. gastrointestinal sensitive individuals are advised to control their single consumption, as oxalic acid may affect mineral absorption. Keep the leaves dry during daily storage to avoid squeezing and damaging the cell structure. Reasonably pairing high-quality protein foods such as tofu and eggs can balance nutrition and alleviate astringency.