[EvaH (OP)]

Hans asks:

I found several scientific papers studying spices, where I could get better estimations of the amounts of soluble and insoluble oxalates in each spice, which was very helpful, yet none of them addressed whether there was a difference between using whole or ground spices in food and drink preparation, and if it impacts the amount of oxalates available to the body.

For instance, cloves had a total of 3245–3969 (mg/100g DM) oxalates, out of which 1520–1677 is soluble according to Singh PP (1973) "The oxalic acid content of Indian spices. Am J Clin Nutr 3–4:335–347". But that was of the dried ground powder, and not of the whole clove.

Of course, adding the ground spice to your food means you're most likely to ingest the whole amount mixed and dissolved within your food, in which case all these studies can be reliable. But when whole cloves, cardamom, or cinnamon for instance are used in cooking, the spice itself is usually discarded, which is also the case when using them in herbal teas.

• So does using whole spices make any difference, is it safer than ground spices?
• Do less oxalates dissolve in water or fat using whole spices, since they have harder access to the internal cellular structure of the spice?
• And does repetitive steeping, adding hot water, and reheating, alter the way or amount of oxalates extracted? Such as the case of traditional Syrian "maghli" (A herbal tea of whole ginger, nutmeg, cinnamon, cloves, and aniseed), where water is added to the pot and reboiled over several days, or whole green cardamom added to yerba mate tea, and hot water is poured into the gourd for several steepings, drinking it over several hours.

Can you help?