Formulation is the process in which a variety of different substances are combined in precise proportions to create a specific product. The proportions of the various substances mixed together in the formulation recipe are determined in the formulation development process. The formulation development process involves repeated experimentation with the ingredient substances to achieve the desired characteristics in the final product: e.g. taste, color, shelf-life, performance, or effectiveness.

Formulation development is highly dependent upon weighing the ingredients accurately. If one step in the weighing process is wrong, the scientist is required to go through the tedious recalculation and adjustment of the other ingredients to make the correction. If this mistake goes unnoticed, products may have different properties or be out-of-specification, resulting in waste, costly reworking or may even pose a risk to the health of the end consumer, particularly in the pharmaceutical and food industries.

Developing the right formulation in the laboratory is a time and labor-intensive process and the different industries are faced with a variety of challenges such as:

• Recipe complexity / number of ingredients, variety of recipes
• Ensuring SOPs are followed
• Skill of the scientist
• Electrostatics
• Documentation and Traceability
• Data management and Data integrity (ALCOA+)

In a formulation, ingredients are typically added one by one to the selected container. The capacity of the balance must be large enough to accommodate the sum of all ingredients plus the container. Depending on the accuracy and capacity required, the use of two different balances may be necessary. 

Formulation development requires accurate execution of the formulation recipe to ensure safe, high-quality products. Selection of the right balance to meet the formulation accuracy requirements is vital, as is ensuring that weighing always takes place in the safe weighing range of the balance. To determine the safe weighing range, the balance's minimum weight must be determined.

If you need support or advice on whether your balance meets the needs of your formulation applications, please don't hesitate to contact us.

Typical sources of error in any weighing process include: Lack of weighing tolerances, use of inappropriate instrumentation, sample spills, temperature variations, air drafts, documentation errors and insufficient scientist skills. As formulation processes involve multiple weighing steps, the combined errors can become significant.

Product Consistency

Every formulation is developed to meet certain criteria, whether it be taste, color, or drug dosage. Without consistency in the formulation, the product will fail to meet expectations, leading to dissatisfied customers, and may even pose a risk to health and/or safety. It is therefore essential to ensure that the weight of each formulation ingredient meets the process tolerances defined in the formulation SOP. The balance used must be able to fulfil the desired process accuracy requirements and should have appropriate quality assurance measures in place to ensure this.

Recipe Complexity

Cosmetics formulations often consist of 50-100 different components, requiring a great deal of effort and concentration from the analyst. Overdosing just one component requires recalculations and adjustments to be made to the ingredients, or the entire formulation must be started again from scratch. The risk of an error occurring can be significantly reduced if the formulation workflow includes steps for the scientist to confirm:

• The next material to be added is the right one
• The amount required of the next material
• The tolerances for the amount to be added

Accurate Weighing of Critical Components

For small quantities of critical or expensive ingredients, it may be necessary to use a second balance with a higher readability and greater accuracy, particularly where there is a large difference between the individual ingredient amounts and the total target mass. Having two balances occupies more lab space, creates extra steps in the workflow, increases the process uncertainties and necessitates a higher investment.

Documentation

To ensure traceability, formulation documentation typically includes formulation ID, substance ID, target mass, tolerances, and actual amount dosed, as well as basic information such as date, time, and user ID. Any recalculations and adjustments must also be documented. Manual recording of all this information carries a huge risk of human error. If there is any mistake in the formulation, it may be impossible to find the source of the error if the data has been recorded incorrectly. 

METTLER TOLEDO XPR precision balances provide you with fast and accurate formulations, even under the toughest weighing conditions, both in the lab or out on the factory floor. Smart quality assurance features, such as StatusLight™, LevelControl and GWP Approved help ensure right-first-time results.

Save your formulation methods on the balance

The built-in formulation application can be tailored to your specific formulations. You can save your customized formulation methods in the method library. The intelligent methods recalculate ingredient amounts automatically depending on the total quantity you want to prepare.

Efficient weighing and documentation

The high stability provided by the unique SmartPan™ weighing pan means you get your results up to twice as fast compared to a standard weighing pan. You can connect a barcode scanner to read in substance IDs quickly and without error. Results and task data are automatically recorded on the built-in results protocol, eliminating time-consuming and error-prone manual data input/output. Multiple interfaces (4 USB, 1 LAN) make it easy to export results to a PC or other system.

Higher Performance Balances

For high accuracy demands, METTLER TOLEDO's higher performance balances are perfect when there is a low net sample weight and a requirement for exceptional repeatability. These higher performance balances enable users to weigh small ingredient quantities with a unique level of precision while still having the capacity to weigh all formulation components on one balance. The need for two separate balances is eliminated.

Comprehensive data management

Connect your XPR balance to LabX laboratory software for comprehensive data management and full traceability. The solution can be integrated with your company's existing ERP/LIMS system, enabling bi-directional transfer of recipes and results. LabX takes care of all process information and calculations automatically. All data is saved securely in a centralized database and reports can be generated at any time. Instruments, tasks and users can all be managed centrally. For highly regulated environments, LabX helps with compliance with FDA ALCOA+ data integrity requirements.

Watch the video and see how XPR balances can save you time and money when preparing formulations thanks to customizable methods, SOP user guidance, automatic calculations and the built-in results notepad.

Weighing results can only be accurate and reliable if you are weighing within the safe weighing range of your balance. Our free guide explains the science behind safe weighing and describes how you can determine the safe weighing range of your balance in three easy steps.

Learn about:

• Absolute and relative measurement uncertainty
• Minimum weight
• Safety factors

Most importantly, find out why all this is necessary to determine your safe weighing range.

METTLER TOLEDO's Advanced Level analytical and precision balances offer an alternative solution for formulation applications, by addressing the challenges faced during sample handling and final documentation.

MS-TS balances feature RS232 and USB interfaces enabling a METTLER TOLEDO P-50 printer and a barcode reader to be connected to the balance.

MS-TS balances have a built-in formulation application which provides step-by-step guidance through the whole formulation process. The recipe code and the ingredient IDs can be entered quickly, and without error, by using barcodes. The application automatically records each weight value and zeros the balance in between the addition of each ingredient. At any time, it's possible to view the ingredients added and see their weight values in a table, pie or bar chart. Once the recipe is complete, the whole formulation can be printed out or saved on a USB memory stick to ensure traceability. The printout can be customized to include up to 3 task IDs, 1 sample ID, 1 user ID, and the time and date.

The time consuming and error-prone manual recording of sample IDs and weight values is eliminated. Hence, the overall process is much faster and more secure.

The combination of a METTLER TOLEDO MS-TS balance with a printer and barcode reader is an efficient and cost-effective solution for creating and tracking formulations.

• Fill-up function
• Configurable printouts
• No more transcription errors

This application guide describes how recipe formulation can be accurately and efficiently undertaken using a simple combination of a handheld barcode reader, a METTLER TOLEDO P-52 printer, and a METTLER TOLEDO MS-TS or ML-T precision balance.

Read how you can solve typical formulation challenges and follow the step-by-step screenshots to see how easy formulation can be.

In the development of a new product, formulation is used on a small scale to create the perfect formulation recipe. For manufacturing, the formulation is scaled-up to produce the quantities required by consumers. Weighing ingredients in much larger quantities requires industrial balances.

For more information on balances suitable for large-scale formulation, please see: