Meat aromas, analysis

The analysis of cooked meat aroma has been reported many times. Even so, there are a large number of factors that need to be considered when carrying... 

Flavorzyme is a commercially available proteolytic enzyme preparation by Novo Nordisk Bioindustrials. It can be used to obtain a meat-like process flavouring from defatted soybean meal. With the help of aroma extract dilution analysis, Wu and Cadwallader [61] showed in their study of 2002 the presence of key aroma compounds of roasty, meat-like aroma in the enzymatically hydrolysed and heated hydrolysed protein, e.g. maltol, furaneol, methanethiol and furanthiol derivatives. 

Some basic food analytical methods such as determination of °brix, pH, titratable acidity, total proteins and total lipids are basic to food analysis and grounded in procedures which have had wide-spread acceptance for a long time. Others such as analysis of cell-wall polysaccharides, analysis of aroma volatiles, and compressive measurement of solids and semi-solids, require use of advanced chemical and physical methods and sophisticated instrumentation. In organizing the Handbook of Food Analytical Chemistry we chose to categorize on a disciplinary rather than a commodity basis. Included are chapters on water, proteins, enzymes, lipids, carbohydrates, colors, flavors texture/ rheology and bioactive food components. We have made an effort to select methods that are applicable to all commodities. However, it is impossible to address the unique and special criteria required for analysis of all commodities and all processed forms. There are several professional and trade organizations which focus on their specific commodities, e.g., cereals, wines, lipids, fisheries, and meats. Their methods manuals and professional journals should be consulted, particularly for specialized, commodity-specific analyses. 

The analysis of natural compounds in foods is also assisted by the use of the purge and trap technique in methods for distinguishing strawberry varieties [100] the aroma of unprocessed foods including gherkin [101], durian [102], garlic [103] and meat [104-107] cheese [108,109] and other dairy products [110] tobacco, tea and coffee [111,112] and peanuts [112]. Food additives including sulphur dioxide [113,114] and food contaminants such as VOCs [115-126], have been recovered by PT, particularly from table-ready foods. Animal [127,128] and plant tissues [129,130] have also been subjected to PT for separation of volatile compounds. 

Despite years of research on irradiation odor, many questions remain unanswered. There is no systematic descriptive sensory analysis of irradiation-induced odor and aroma in RTE meat products. The description of off-odor has been mostly reported for raw meats. Limited studies have indicated that the off-odor is not always found in low dose irradiation-induced RTE products. The descriptive analysis may be conducted on RTE products irradiated in higher doses, so distinguished odors can be detected. 

Gasser, U., W. Grosch, Aroma extract dilution analysis of commercial meat flavorings, Zeitschrift Lebens. Untersuch. Forsch, 190, 6, p. 511, 1990. 

In general, nitrosamines arise only in very low concentrations. Since some of these compounds are a great health hazard, they should be detectable below 0.1 ppm in food for human consumption. The same procedures are available for identifying volatile nitrosamines which have been described earlier for the analysis of aroma constituents (cf. 5.2). However, precautions should be taken during the isolation step. Isolation of nitrosamines should not proceed at low pH since an acid medium in the presence of residual meat nitrites promotes further de novo synthesis of nitrosamines. Since the isolated fraction of neutral volatile confounds, which also includes nitrosamines, is highly conplex in composition, reliable nitrosamines identification by gas chromatographic retention data is not possible. Additional mass spectrometric data are needed to verify the chemical structure. 

Three commonly used extraction techniques for the analysis of aroma are simultaneous distillation/extraction (SDE), dynamic headspace adsorption on Tenax TA (Buchem N.V., Apeldoorn, The Netherlands), and solid-phase microextraction (SPME) [1,2]. All of these techniques have positive aspects and drawbacks, and these are described. In SDE the sample is boiled for 1 to 2 hr and so precooking may not be necessary, although the meat is usually minced to maximize surface area for the extraction process. The other techniques can be used to examine either a chopped or a whole piece of cooked meat. 

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