Categoria: Contract Analysis

At our applications lab we do several analysis. We´d like to share an interesting example with you.

Coffee is one of the most popular and widely consumed beverages in the world today due not only to its stimulating effects on the central nervous system, but also because of its taste and aroma.

One of the crucial steps in processing coffee beans is the grinding, since different types of final use (e.g., espresso, filter coffee, mocha, capsules) require different grinding degrees to adjust specific parameters such as bitterness, acidity, sweetness, or aroma.  All these parameters are highly influenced by particle size.

It is important not only to adjust the particle size of coffee powder, but also to control the overall uniformity of the grinding process.

In the past, sieve analysis was the main method to carry out size measurements, however this technique is time consuming and quite limited. Laser Diffraction is an alternative technique that allows automation and delivers results with higher quality, quicker and in real-time, optimizing the desired product properties.

The right side graphic shows the particle size distributions of four coffee samples in capsule and one sample of soluble coffee. Through its analysis we can observe that soluble coffee has a higher D90 and D50 than coffee in capsules, which is expected considering the differences in the grinding process. Also capsule coffee present different size distributions depending on its type (expresso, decaffeinated, ristretto or lungo)

The equipment used in this work was Mastersizer 3000’s with Aero S dry powder disperser from Malvern, a laser diffraction analyzer that delivers measurements from 10 nm to 3.5 mm using a single optical measurement path, making it suitable for an extremely wide range of application. For more information, please click on the Brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

At our applications lab we do several analysis. We´d like to share an interesting example with you.

Protein is a nutrient human being needs to grow and repair cells and to work properly. Protein is found in a wide range of food and it is important to get enough protein in daily diet.

The increase in consumer demand for protein-rich foods has led to increased control of their content in various products, particularly milk and its by-products.

Whey Powder is one of the best-known supplements used by athletes as it contains the essential amino acids for muscle recovery and construction.

Milk Powder is marketed because it offers preservation advantages, since it does not need to be refrigerated due to its low moisture content. Another advantage is to reduce its transport volume.

In this study, elemental analyses by combustion were performed on milk and whey powder samples to quantify its nitrogen amount and estimate the protein content in the samples.

Table 1: Carbon and nitrogen results obtain for whey powder and milk powder and their respective Protein values.

SAMPLE	C (%)	N (%)	Protein (%)
Whey Powder	40.95 ± 0.11	1.98 ± 0.02	12.6 ± 0.1
Milk Powder	45.51 ± 0.12	5.39 ± 0.06	34.3 ± 0.3

The instrument used was the vario MACRO cube CHNS, from Elementar®, using combustion of the sample to promote an instantaneous oxidization into simpler compounds which are then detected by thermal conductivity. For more information, please click on the brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

Contract Analysis | Polymers | X-Ray Diffraction (XRD)

Insulation of electrical conductors is a critical safety feature to prevent short circuits, fire hazards or electric shocks. An insulator is a material or medium that has a high resistivity towards conducting electric current. There are numerous materials employed to achieve such insulation like polymers (typically Polyvinyl Chloride (PVC), Polyethylene (PE) and rubbers), ceramics, sand, air or vacuum.

Insulation of electrical wires and home cables can be achieved by covering them with suitable polymer layers. Its properties – mechanical behaviour, chemical stability, fire resistance and others, are usually modified or improved by additives.

In this study, identification of additives on the surface of a polymer insulator of electrical wires was performed using X-Ray Diffraction (XRD) with parallel beam geometry. The obtained diffractogram, shown below, allowed the identification of two different additives: calcite-for improved stiffness and impact resistance, and a Mg-Al layered double hydroxide- for flame retardation.

The equipment used in this work was Smartlab from Rigaku equipped with a 9kW rotating anode X-Ray generator. Smartlab is an automated multipurpose X-ray diffractometer with a theta/theta configuration. For more information, please click on the brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.
Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

The freeze-drying process is important in the pharmaceutical and biotechnology industries to stabilise, store, or increase the shelf life of formulations and other biologicals. Freeze-drying uses a process called lyophilization to lower the temperature of the product below freezing, and then vacuum is applied to extract the water in the form of vapour (sublimation). Knowing the phase diagram of the formulation is paramount to define and optimise the freeze-drying process.

Formulations may form a eutectic system which is characterized by the eutectic melting line, the lowest achievable melting temperature across the entire composition range and, at a specific homogeneous mixing ratio, they present a single melting point. Eutectic system characterization is important since the freeze-drying process conditions must be set based on the eutectic temperature.

In this study, a thermal characterization of a freeze-dried formulation was performed using Differential Scanning Calorimetry (DSC). The picture shows a DSC thermogram where two endothermic effects are visible. The first one (yellow arrow) corresponds to the transition S/S+L of the eutectic mixture, while the second one (red arrow) corresponds to the transition S+L/L, as exemplified by the phase diagram on the left.

The equipment used in this work was DSC 214 Polyma from Netzsch equipped with an intracooler (temperature range from -40ºC to 600ºC). For more information, please click on the Brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

At our applications lab we do several analysis. We´d like to share an interesting example with you.

Cereals, consumed as whole, treated grains or in milled form (flower), constitute the base of all human and farm animals feed. Worldwide, cereal production in 2017/2018 surpassed 2 700 million tons (data obtained from FAO website), with wheat and rice representing 47%.

Industrial milling is achieved by means of stainless-steel blades which, if not properly maintained, can contaminate the flower with iron, chromium and nickel.

In this study, two milled products of the same cereal were analysed to verify the possible contamination with metals during the milling process.

X-Ray Fluorescence (XRF) is a non-destructive elemental analysis technique which provides both qualitative and quantitative data ranging from sub-ppm to 100% (m/m), depending on the equipment, matrix and element considered.

The Image 1 is a zoomed view of the overlaid spectra of both samples analysed. This region evidences the presence of Chromium and Nickel in the sample identified as “Suspect” while absent in the sample identified as “Good”. Additionally, the iron amount is significantly higher in the “Suspect” sample. Both results indicate that the “Suspect” sample has indeed been contaminated by the stainless-steel blades during milling due to its wear.

The equipment used in this work was Supermini200 from Rigaku, a tabletop WD-XRF. The range of analysed elements goes from Oxygen to Uranium and can measure both solids and liquids in helium or vacuum atmosphere. For more information, please click on the Brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

At our applications lab we do several analysis. We´d like to share an interesting example with you.

Pigments are designed and produced to be insoluble particles used to impart colour in a variety of materials. The diverse range of its chemistries, the end use requirements, and the broad range of colours available create a challenge for chemists when incorporating them, being stability and settling one of the many factors to consider. The first steps in the pigment dispersion process are wetting and separation of the pigment. However, if the pigment dispersion is not properly stabilized, flocculation will result.

One of the main mechanisms to obtain pigment stabilization is charge repulsion, in which particle surfaces with like charges repel each other. Properly stabilized pigment dispersions prevent flocculation and agglomeration.

Zeta potential serves as a reference as to how stable the formula will be. Pigment dispersions with a zeta potential between +30 mV and -30 mV have a high probability of being unstable.

In this study, zeta potential was measured by Electrophoretic Light Scattering. Sample was a water dispersion of a pigment used in the automotive industry. Results obtained (image 1) are compatible with a stable dispersion as average zeta potential is -42,3 mV.

The equipment used in this work was Zetasizer from MalvernPanalytical and sample cell was a folded capillary cell. For more information, please click here.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

Metallic Alloys have always been one of the cornerstones of mankind evolution for millennia. Naturally occurring or man-made, they have been used in construction, coinage, automotive industry, jewellery, technology development, and many others. Alloys are a combination of at least one metal element with other metallic or non-metallic elements.

The chemical composition of the alloys, namely the base and alloying elements and their relative proportions (as well as the heat treatment), are decisive to define their mechanic and reactivity behaviour. Different alloys are then selected according to the desired characteristics for the intended usage. Due to the huge variety of existing alloys and due to its relevance, the chemical composition ranges of the existing alloys are established by a series of international standards. It is, therefore, of extreme importance to be able to measure the chemical composition of an alloy.

In this study, a metallic cylinder block was analysed to confirm if it was made of Stainless Steel AISI 316L. The analysis was performed using Optical Emission Spectroscopy (OES) technique, where the metal surface is hit and burned with a high voltage spark in argon medium. This produces a characteristic round black burn spot as shown in the figure (image 1). The measured chemical composition was indeed compatible with Stainless Steel AISI 316L.

The equipment used in this work was Foundry Master Pro 2 from Hitachi. For more information, please click in the brochure.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

Polymers blends are physical or mechanical mixtures of two or more polymers, analogous to the metal alloys. The purpose of the blend is to enhance or impart additional characteristics to the polymers that best suit the desired application.

The blended polymers can be miscible, immiscible, or partly miscible in certain conditions. Most polymer blends are immiscible or partly miscible and, in this case, the individual polymer characteristics remain. This means that the blends can be separated in their individual polymer constituents.

In this study, an immiscible two-polymer blend was analysed with the purpose of quantifying both polymers. Thermogravimetric Analysis (TGA) was used for this analysis. Since both polymers have close decomposition temperatures, the quasi-isothermal approach was used to separate both phenomena and allow proper quantification.

The obtained thermogram, shown in the image 1, showcases two mass loss steps. Based on the weight left on the crucible as the result of the pyrolysis (residual mass), mass losses were normalized to 100%, with one polymer being calculated as 87% and the other one as 13%.

The equipment used in this work was an STA 449 Jupiter from Netzsch®. For more information, please click on the brochure .

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.

Microcapsules are hollow microparticles composed of a solid shell surrounding and entrapping substances in their core. They are containers that are able to release their contents when appropriate or needed and in a controlled way. There are numerous substances that can be encapsulated, such as pesticides, perfumes, API’s, dyes and pigments, flavours or food additives. It all depends on the intended application.

Microcapsules find in Textiles one of its major areas of industrial application. They started being used in textile products during the 1970’s and the range of applications increased dramatically with the technological advances. One of the applications is the dispersion of microcapsules of fragrances in woven textile fibres. Such fragrances are released when the microcapsules burst due to mechanical friction, such as rubbing.

In this study, a textile impregnated with perfume microcapsules was analysed by Scanning Electron Microscopy (SEM) to verify the efficiency of the dispersion. The pictures below show that the microcapsules are well dispersed in between the woven fibres, with sizes ranging from approx. 5 to 50 µm.

The equipment used in this work was SEM Phenom ProX from Thermo Fisher Scientific. For more information, please click here.

Analysis reports can be prepared in English (default), Portuguese or Spanish.

Other services can be requested on demand. They include analytical methods development and validation, route cause analysis support, reverse engineering support and technical consultancy in material characterization.