Functional & Thermal Analysis in Food
Functional and physical testing in food is used to evaluate key properties of food products to obtain information about the quality of the food product and manufacturing process parameters that are critical for guaranteeing product consistency.
PerkinElmer is a leading supplier of advanced analytical instruments and analyzers for the food and agricultural industries. Our wide range of innovative products for quality control of grain, flour, dairy, feed and food for functional analysis are unique in the industry. Our analyzers test functionality of ingredients for product development, quality and process control and quality assurance. They are placed at field and manufacturing sites, in R&D facilities, and in laboratories. These analyzers help to develop better products, reduce waste and improve efficiency every day.
The effect of gluten quantity and quality in the flour used for breads, cookies, crackers and pasta is dramatic. The wet gluten quantity of the flour strongly influences bread volume. Using the Glutomatic® System you will be able to determine the baking quality of wheat and flour.
Falling Number is the international standard method for determination of alpha-amylase activity in grain and flour to detect sprout damage, optimize flour enzyme activity and guarantee soundness of traded grain.
The method is standardized by international bodies such as the ICC, CGA, ISO and ASBC in the standards: ICC/No. 107/1 (1968), AACC/No. 56-81.03 (1972), ISO/No. ISO/DIS 3093 (1974) and ASBC Barley 12-A.
World Standard - The Perten Falling Number models are the only validated instruments for Falling Number testing according to international standards: AACC/No. 56-81.03, ICC/No. 107/1, ISO/DIS 3093.
Among the rheological properties of dough we can mention elasticity, extensibility, resistance to deformation and viscosity. Variations in water and protein content, changes in the fibrillar structure of the protein, starch, starch damage, pentosans, gluten strength and the actions of enzymes on the dough components all affect dough behavior. Due to the complex nature of dough behavior an empirical instrument test is desirable. The doughLAB determines water absorption of flour, dough development time and other dough mixing parameters.
The Rapid Visco Analyser is a unique tool for product development, quality and process control and quality assurance. The RVA is a cooking, stirring viscometer with ramped temperature and variable shear capability optimized for testing the viscous properties of starch, grain, flour and foods. The instrument will analyze as little as two or three grams of sample using international standard methods or your own tailor-made test routines of mixing, measuring, heating and cooling.
Evaluation of texture is often based on sensory evaluation and experience. The TVT 6700 texture analyzer is rapid, objective and more sensitive and reproducible than subjective sensory judgement. The TVT 6700 applies controlled conditions of stress or strain to food and other samples to measure a complete texture profile. It accurately measures compressive and tensile force and position over time using standard test modes including single and multiple cycle compression, tensile strength, compress-and-hold, extend-and-hold, fracturability and springback to describe product texture. Data is captured as a graph and stored in separate projects/files for analysis and export to spreadsheet programs.
DSC is particularly suitable for analysis of food systems because they are often subject to heating or cooling during processing. The calorimetric information from DSC can be directly used to understand the thermal transitions that the food system may undergo during processing or storage. DSC is easy to operate and, in most cases, no special sample preparation is required.
Our comprehensive line of high-performance DSC applications, instruments and services – combined with our expertise in materials characterization -- helps you push the envelope on your research, offering deeper insights and the best user experience available.
For simultaneous, real-time measurement of sample weight change and heat flow, count on our easy-to-use simultaneous thermal analyzers (STAs).
With innovative sensor technology and a compact furnace design, you get twice the thermal capability in one compact instrument.
Measure changes in sample mass as a function of temperature with high levels of sensitivity. Our Thermogravimetric Analyzers (TGAs) combine the best available sample atmosphere control, high throughput automation, and advanced hyphenation technology for better understanding of gases evolved during experiments. Delivering the throughput and performance you need in an easy-to-use, easy-to-maintain, automated system, our TGAs are perfect for Food and Food Packaging.
Extrusion and other cooking processes of foodstuffs such as breakfast cereals, snack foods and animal feeds have marked effects on the starch in the sample. The degree of cook can be assessed by re-cooking the product in the RVA to measure the original degree of transformation in the starch.
This method is applicable to unmodified corn and other cereal starches. A 13-minute test in the RVA provides a rapid yet accurate alternative to study the cooking properties of unmodified cereal starches, making it suitable for both research and quality control applications.
The onset temperature of rice flour gelatinization has historically been estimated using AACC Method 61-01 - Amylograph method for milled rice (20% solids). This method requires a large quantity of sample, which is often not available for those involved in activities such as rice breeding or research. This RVA method follows AACC Method (pending), the objective to which is to estimate the onset temperature of rice flour gelatinization using a small quantity of sample with the Rapid Visco Analyser.
This high-temperature RVA method is designed to mimimc retorting, allowing assessment of the suitabilitu and stability of polysaccharide thickeners (eg. Gums, modified starches) in the formulation for high temperature processing.
The ability of the components of a product to withstand high-temperature processing conditions is of interest to formulators, who must balance the need for acceptable product rheology with safety and throughput. The Rapid Visco Analyser (RVA) can perform high temperature tests. The method presented in this document is applicable to any liquid or hydrated ground material including, but not limited to, unmodified starches, flours, whole meals, gums, diary ingredients, and other formulations.
This high temperature RVA method is applicable to any unmodifies and modified starches and their derivatives, including composites with hydrocolloids and lipids. High shear is used in the method to approximate typical processing conditions for these ingredients, which are commonly used as far replacers, gelling agents and stabilizers, and as paper wet end, size press and coating additives.
The method uses a maximum test temperature of 91ºC, to avoid boiling of water in the RVA canister at high altitudes (900-2100 m, or 3000-7000 ft). The pasting properties of starch and starch-containing products are readily assessed in the RVA. During the test, the starch is gelatinized with consequent rise in viscosity, subject to high temperature and controlled shear during which its stability is revealed, then cooled to provide an indication of setback during gelation. Samples can be assessed for pasting temperature, peak paste viscosity, time to peak, temperature at peak, hot and cold paste viscosity, breakdown, setback, final viscosity and other parameters.
Barley must retain high viability level in storage, typically above 95%, to be accepted for malting. The RVA Stirring Number test provides a rapid method for assessing sprout damage in malting barley.
In this work viscous properties of xanthan gum in water and other solutions at various heating and shear rates are evaluated. The Rapid Visco Analyser (RVA) is a cooking stirring viscometer with ramped temperature and variable shear profiles optimized for testing viscous properties. The instrument includes international standard methods as well as full flexibility for customer tailor-made profiles. Combining speed, precision, flexibility and automation, the RVA is a unique tool for product development, quality and process control and quality assurance.
The method is applicable to unmodified and to acid thinned dent corn starches. These food and industrial starches are used as thickeners, gelling agents, sizes and coatings in products such as puddings, gravies, sauces, confection and paper. The final temperature of 65°C (149°F) is used to rapidly stabilize viscosity and minimize retrogradation. The Rapid Visco Analyser (RVA) is a cooking stirring viscometer with ramped temperature and variable shear profiles optimized for testing viscous properties.
The method is applicable to unmodified dent corn starches. The final temperature of 65°C (149°F) is used to rapidly stabilize viscosity and minimize retrogradation. Combining speed, precision, flexibility and automation, the RVA is a unique tool for product development, quality and process control and quality assurance.
The pasting behavior of pasta depends, to a great extent, on the ingredient and process effects. The cooking properties and final quality of the pasta are affected by treatments, such as drying, sheeting or extruding, during the manufacturing process. Combining speed, precision, flexibility and automation, the RVA is a unique tool for product development, quality and process control and quality assurance.
This procedure is based on the method of Goode et al. (2005) using malted and unmalted barley, to study the effect of endogenous enzyme and added adjunct levels, respectively, on mash viscosity. This profile can be used to check the suitability of a batch of grain for mashing, or for checking the appropriate level of added adjunct in the mashing system.The RVA is used as a laboratory-scale rheological tool for the characterization of mash viscosity, allowing the brewer to monitor the processes that are taking place during mashing.
The method is first used to establish the malting potential calibration for the variety of interest. To do this, a number of malts varying in known malting potential for the selected variety are tested. From the viscograms, the peak viscosity, time to peak, breakdown, peak area, holding strength and final viscosity are measured. These parameters are fitted as dependent variables against conventional measures of malting quality using standard regression techniques. The loge transformation may be used as appropriate. The most highly correlated viscogram parameters may subsequently be measured in malts of unknown potential for the same variety, using the regression equation to predict the potential malting quality of the sample. Good correlations using loge time to peak and loge peak area have been demonstrated.
This application describes the use of an RVA to assess the effect of added ingredients on the mashing behavior of a malt. Malts are tested with and without added enzymes, adjuncts or chemicals (e.g. pH modifiers). The differences are used to determine the improvement or deterioration in mashing behavior of the malt due to the addition.
The method is applicable to cationic corn starches (waxy and dent), including those that have also been acidthinned. These industrial starches are used widely for wet end, size press and coating applications in papermaking. High shear is used during cooking to approximate typical processing conditions for thesestarches.
Raw starch pasting curves have a typical low initial (cold) viscosity, followed by a viscosity peak caused by swelling of the raw starch granules, and a relatively high setback viscosity. Processing by thermal and mechanical inputs will progressively reduce peak and setback viscosities. Cold viscosities will increase through a pre-gelatinization effect, and then eventually decrease through granule rupture and dextrinization, as the prior degree of cook increases. The RVA can therefore be used to assess how cooked a product is, with applications for system characterization, at-line process control, product development, scale-up, transfer, troubleshooting and assessment of competitive products.
The RVA can be used to assess the gluten quality in soft wheat flour. Gluten proteins increase suspension viscosity when dispersed in dilute lactic acid. This viscosity can be measured using the RVA. The method is most useful for assessing soft wheat used in pastry and biscuit manufacture. This method has limited screening value for bread making wheat where dough rheological properties are important.
Rice sensory quality is of prime importance throughout Asia where rice is a staple food. This RVA method, developed by The Food Agency in Japan, provides a longer profile than Method 10, to better discriminate between rice samples of similar quality.
Wheat gluten is used largely as an additive to improve baking quality of leavened bread, but also finds use in other products such as pet foods. During commercial preparation, wheat gluten is usually partially denatured by heat, reducing its vitality. The functionality of wheat gluten can be assessed by heating and cooling in aqueous ethanol in the RVA.
Wheat flour quality can vary greatly between samples. The quality of the gluten protein in wheat flour largely determines its suitability for use in many products including pan breads, flat breads, cakes, pastries and alkaline noodles, although each application requires a different quality. For example, strong wheat flour is preferred for commercially produced pan breads because of its good mixing tolerance and superior baking qualities. Combining speed, precision, flexibility and automation, the RVA is a unique tool for product development, quality and process control and quality assurance.
The Rapid Visco Analyser (RVA) is a cooking stirring viscometer with rampedtemperature and variable shear profiles optimized for testing viscous properties.The instrument includes international standard methods as well as full flexibilityfor customer tailor-made profiles. Combining speed, precision, flexibility andautomation, the RVA is a unique tool for product development, quality andprocess control and quality assurance.
Cheese melting temperature and viscosity are important quality characteristics for processing and consumption of cheeses such as mozzarella. The melt characteristics of grated cheese can be measured in the RVA in the presence of a small amount of propylene glycol. The RVA parameters including temperature at melting, minimum viscosity and temperature at solidification are good indicators of the meltability of a processed cheese sample.
The processing and handling behavior of food fats has been found to depend upon the solid-to-liquid fat ratio in the food sample. Many rheological or flow properties, and their resultant effect on the texture of the final product, stem fromthis fat ratio index. The Power Compensation or double furnace DSC yields excellent results for foods including thefat nature and content.The fast responsiveness of the Power Compensation DSC provides the highest possible resolution and this is critical for characterizing the various polymorphic melting forms associated with fats in foods.
This note describes a number of important food applications utilising the PerkinElmer DSC demonstrating the versatility of the technique as a tool in the food industry.