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Nutritional analysis is the process of determining the nutritional content of food. It is a vital part of analytical chemistry that provides information about the chemical composition, processing, quality control and contamination of food. It ensures compliance with trade and food laws. There are a variety of certified methods used for performing nutritional analysis.
For this approach, food companies send samples of food to laboratories for physical analysis. By utilizing scientific methods and equipment the food sample is analyzed for the different components that compose the nutritional information needed.
The laboratory analysis measures the actual levels of nutrients in the prepared food, thus providing a high level of accuracy of the analysis. The analysis accounts for the changes in nutritional value that occur due to the cooking and processing of the food. This is of extreme value as calories tend to increase or decrease during the cooking process depending on the method used. For example, added fats increase calorie content during frying and decrease during grilling. Moreover, salt can be added during food preparation which increases the final sodium content of the dish.
Food item sampling, food analysis and results interpretation require specialized expertise.
Nutrient Analysis Software
This technique allows the user to determine the nutritional content of food. However, the quality of the analysis largely depends on how accurate and standardized the recipes are.
Standardized recipes are ones that are adapted and retrieved for use by a foodservice operation. Using the same quantity and quality of ingredients in standardized recipes yield the same results in the nutrition analysis.
This analysis is limited by the selection of ingredients available in the food database. This approach does not consider the effects of cooking and processing on the food which can dramatically alter the content.
It is of great importance, and advisable, that a food preparation and nutrition expert performs the analysis.
Laser Scanning Confocal Microscopy (LSCM)
This method is used in food analysis and research as an addition to chemical and physical analysis of food samples. As compared to the Laser Scanning (LS) method, the LSCM focuses the illumination on specific positions of the sample. A small portion is illuminated at a time which increases the contrast and decreases the out-of-focus blur. The images of the sample can be looked into individually or can be grouped forming a 3D image using image analysis software. The ability to observe optically small sections of the food sample provides an insight into the 3D structure of the product.
LSCM utilizes compound-specific fluorescent probes making it possible to image the presence, state and spatial organization of components, such as protein and fat. This technique allows for the close and detailed examination of the physical state and the movement distribution of components within multi-components food.
Immunoassays are widely used in food analysis for detecting and quantifying proteins in a given food for three reasons.
First, immunoassays are used for the detection of cheap ingredients used to substitute high-quality products. Examples of that include the addition to beef and pork of cheaper meats such as sheep, goat and rabbit or of soybean proteins; the addition of cow’s milk in goat’s milk products; the replacement of more expensive nuts such as hazelnuts with cheaper ones.
The second application of immunoassays is in the detection and quantification of proteins involved in intolerance and allergic reactions to certain foods.
The third reason for using this technique is because it provides a way to detect tissue-specific antigens present in food that might be associated with transmittable encephalopathies.
This method involves separating ionized atoms and molecules according to their difference in mass to charge ratio. Since atoms and molecules have different fragmentation patterns, mass spectrometry provides a way of identification of structural components.
Gas chromatography-mass spectrometry (GC-MS) provides the pathway for the use of mass spectrometry in food analysis. GC-MS is a method for qualitative and quantitative analysis of components such as sterols, alcohol, fatty acids and low mass carbohydrates. It is also involved in the detection of food contaminants such as pesticides, pollutants, toxins and drugs. It is considered as a major method for fatty acid compositions detection. GC-MS is used for the quantification of polyphenols in fruits and vegetables. Polyphenol is a category of chemical compound that is naturally present in plants.
Food analysis is focused on the nutritional value of the product, the additional materials added and the presence of any toxic components and the effect of processing on the food structure and quality.
These are just some of the currently available methods of food analysis. Food analysis is a complex matrix that usually involves the use of several techniques to complete a full nutritional analysis. The growing regulations surrounding food production have contributed to the growth of research in the food production industry.