— For b), when the powder contains hard lumps which do not dissolve in ammonia solution. This is noticeable by a distinct smell and the result of the determination will be too low. In such cases, a method using the Weibull-Berntrop principle is suitable, e.g. ISO 8262‑3|IDF 124‑3.

— For c), The method is not applicable to sour creams with starch or other thickening agents. When separation or breakdown of fat occurs, a method using the Weibull-Berntrop principle is suitable, e.g. ISO 8262‑3|IDF 124‑3.

— For e), to products which do not dissolve completely in ammonia solution, as the result of the determination will be too low. With such products, a method using the Weibull-Berntrop principle is suitable, e.g. ISO 8262‑3|IDF 124‑3.

— For g), to milk-based edible ices and ice mixes in which the level of emulsifier, stabilizer or thickening agent or of egg yolk or of fruits, or of combinations of these constituents, makes the Röse-Gottlieb method unsuitable. With such products, a method using the Weibull-Berntrop principle is suitable, e.g. ISO 8262‑2|IDF 124‑2.

— For h), to products which do not dissolve completely in ammonia due to the presence of starch or dextrin at mass fractions of more than 5 % (in dry matter), or to the presence of hard lumps. For such products, a method using the Weibull-Berntrop principle is suitable, e.g. ISO 8262‑1|IDF 124‑1.