Apple juice and QC

Refractometry is widely used in the quality control of juice and other beverages.

Apple juice

Apple juice is one of the most common fruit juices in the world. It is produced by the pressing of apples. This juice can then be further processed by enzymatic treatment, filtering, pasteurization and/or dehydration to produce a concentrate. Additionally various supplements such vitamin C and other preservatives may be added.

Quality control

Proper quality control of juice and beverages is of major importance, both in terms of consumer experience and safety. A large variety of different components and factors can be analysed. These include, but are not limited to, salt, sugar, acidity, colour, flavor, odour, enzymes, total solids and contaminations. Some of these, like correct colour, can be measured on a standard spectrophotometer. Others, like salt and sugar, do not absorb light in the UV-visible spectrum, but can be measured using refractometry. Refractometry has the advantage of measuring the total of everything in the sample, i.e. if anything is off, it will let you know.

Principle

Traditionally, a specialized refractometer has been required for determination of the refractive index. However, with the innovative NanoCuvette™ One, a nanosensor is installed in a cuvette, allowing determination of the refractive index to be carried out in a standard spectrophotometer. This way even compounds that do not absorb light in the UV-visible spectrum can be measured with a conventional spectrophotometer.

Safety precautions

This method does not entail any safety precautions. Please refer to common laboratory practices.

Measurement