Application Method

pH Measurement of Jam and Jelly

Application Method

Use the Right Sensor to Improve the Quality of Your Jam and Jelly pH Measurements

pH of jam and jelly
pH of jam and jelly

Measuring the pH of jam and jelly with conventional sensors is a difficult task. Conventional pH sensors with a blunt spherical tip are not able to penetrate through semi-solid samples like jams and jellies. Forcible penetration attempts into the sample are not recommended as the sensors cannot withstand the pressure of being pushed into a semi-solid sample. The delicate sensing membranes with spherical shapes can be damaged during this measurement process. This along with a few more factors cause unstable readings and longer response times.

METTLER TOLEDO's InLab Solids Pro-ISM is a specialized sensor for measuring the pH of jam and jelly with accuracy and precision. The sensor has a spear shaped tip made of toughened glass that allows direct insertion into solid samples and is resistant to breakage. The low maintenance solid XEROLYT®EXTRA polymer reference system offers a clog-free open junction, which eliminates the risk of sensor fouling. The specialized design and overall sensor technology of the InLab Solids Pro-ISM ensures direct measurements of solid jam and jelly samples, which is critical for ensuring reliability and consistency during their production.

In this application note on the pH measurement of jam and jelly find out which sensor will enable direct and reliable measurements of pH.

The following sections cover additional details about jam and jelly, its composition and importance of pH in manufacturing.


What are jam and jelly?

Jam and jelly are fruit preserves that allow for enjoying seasonal fruit throughout the whole year. These semi-solid food products are made from a variety of fruits. Depending on the flavor, either a single fruit or a com¬bination of fruit pulps are used in the making of a jam, while jelly is made from strained fruit juices.


What is the composition of jam and jelly?

The main ingredients along with fruit is comprised of 1% pectin, 65% sugar and acid concentration to bring the pH within 2.7 - 3.6 range. For a premium batch and flavor consistency, the ratio of these ingredients as per the recipe must be carefully maintained.


Does the production of jam and jelly have to comply with certain guidelines?

For a stable and safe product, the process has to be followed as per the guidelines outlined in CFR Title 21 Part 150. For instance, in sugar-free or low sugar jam or jelly products, special considerations have to be taken due to the reduction of the amount of sugar in the final product. To stabilize the flavor of jams with low sugar levels, more fruit content is required along with a reduced acidity. Hence, a different balance of sugar, acidity and fruit flavor is used. pH control in acidified food products should comply with manufacturing process regulation outlined in 21 CFR 114. Additionally, the person supervising the production needs to be FDA approved as specified in 21 CFR 114.10.


What is the importance of pH measurement in jam and jelly?

The main ingredient pectin requires a specific pH in order to solidify and create the characteristic flavor and gel texture of the final product. In order to maintain consistency in the desired quality of a product, texture and flavor, monitoring pH is important and therefore plays a vital role.

For more information on the advantages of using METTLER TOLEDO's sensors for measuring the pH of jam and jelly, download our application note for free by clicking the button above.