Carrageenan only the lambda form (and the sodium salts of the other two) are soluble. When used in food products, carrageenan has the EU additive E numbers E407 or E407a when present as "processed eucheuma seaweed". Technically carrageenan is considered a dietary fibre. In parts of Scotland and Ireland, where it is known by a variety of local and native names, "Chondrus crispus" is boiled in milk and strained, before sugar and other flavourings such as vanilla, cinnamon, brandy, or whisky are added. The end-product is a kind of jelly similar to panna cotta, tapioca, or blancmange. Although carrageenans were introduced
Simultaneously extracted metals and Acid-volatile sulfide Simultaneously extracted metals and Acid-volatile sulfide Simultaneously extracted metals/Acid-volatile sulfide (SEM-AVS) is an approach used in the field of aquatic toxicology to assess the potential for metal ions found in sediment to cause toxic effects in organisms dwelling in the sediment. In this approach, the amounts of several heavy metals in a sediment sample are measured in a laboratory; at the same time, the amount of acid-volatile sulfide (sulfide which can be liberated from the sediment by treatment with hydrochloric acid) is determined. Based on the chemical interactions between heavy metals (SEM) and acid-volatile sulfide (AVS), the concentrations of these