Pork flavors

Esters formed during heating of lipids are contributors to pork flavor. Raw pork contains only a small number of esters, while cooked pork contains significantly more, and acetates are the most prominent volatiles. Esters of cooked pork are derived from C1-Ci0 acids, which impart a fruity sweet note to pork meat (J16). Beef contains a higher proportion of esters derived from long chain fatty acids which possess a more fatty flavor character (16). The characteristic odor of mutton is believed to be due to the evolution of 4-methyloctanoic acid, 4-methylnonanoic acid and similar compounds during heating (17). 

Similar reactions have been used to generate pleasant pork notes from the reaction of natural Isovaleraldehyde and natural Ammonium Sulfide, as shown in the following figure. The chemistry of this pork flavor formulation has been the subject of several patents and numerous publications (equation 13). 

Textured Soy Proteins. Textured vegetable proteins, primarily textured flours and concentrates (50% protein and 70% protein, dry basis, respectfully) are widely used in the processed meat industry to provide meat-like structure and reduce ingredient costs (3-6, 9-10). Available in a variety of sizes, shapes, colored or uncolored, flavored or unflavored, fortified or unfortified, textured soy proteins can resemble any basic meat ingredient. Beef, pork, seafood and poultry applications are possible 03, 4-7, 15, 19) Proper protein selection and hydration is critical to achieving superior finished product quality. Textured proteins have virtually no solubility and, thus, no ability to penetrate into whole muscle tissue Therefore, textured soy proteins are inherently restricted to coarse ground (e.g. sausage) or fine emulsion (e.g. weiners and bologna) products, and comminuted and reformed (i.e. restructured) meat products. None are used in whole muscle absorption or injection applications (2-4, 6, 11). 

Cereal flour, buckwheat flour, soy flour, seafood allergens, pork, sesame seeds, sunflower seeds, lupin, spinach, sarsaparilla root dust, cocoa, coffee dusts, green tea, egg protein, lactalbumin, milk powder, casein, honey, a-amylase, glucoamylase, pectinase, gluconase, pepsin, pectin, spices, carmine, flavorings... 

Tikk, M. Tikk, K. T0rngren, M. A. Meinert, L. Aaslyng, M. D. Karlsson, A. H. Andersen, H. J. Development of Inosine Monophosphate and Its Degradation Products during Aging of Pork of Different Qualities in Relation to Basic Taste and Retronasal Flavor Perception of the Meat. J. Agric. Food Chem. 2006, 54, 7769-1711. 

Homstein and Crowe 18) and others (79-27) suggested that, while the fat portion of muscle foods from different species contributes to the unique flavor that characterizes the meat from these species, the lean portion of meat contributes to the basic meaty flavor thought to be identical in beef, pork, and lamb. The major differences in flavor between pork and lamb result from differences in a number of short chain unsaturated fatty acids that are not present in beef. Even though more than 600 volatile compounds have been identified from cooked beef, not one single compound has been identified to date that can be attributed to the aroma of "cooked beef." Therefore, a thorough understanding of the effect of storage on beef flavor and on lipid volatile production would be helpful to maintain or expand that portion of the beef market. 

Supercritical COj (SC-CO2) was used to reduce the lipid of meat and the cholesterol of meat and beef tallow. Lipids can be removed quantitatively from dried muscle foods by SC-CO2, but relatively high temperatures are needed. The use of SC-CO2 in conjunction with ethanol, adsorbents and multi-separators also reduced the cholesterol of beef tallow. SC-CO2 was also used to concentrate volatile flavor compounds from beef and pork fat. The volatile components in various extraction fractions were identified and quantitated. 

Four aspects of research involving the use of SFE for the improvement of quality of muscle food products are briefly discussed. These include supercritical CO2 extraction of lipids fi om fresh ground beef and from dried muscle foods the extraction and separation of lipid and cholesterol from beef tallow supercritical CO2 extraction of flavor volatiles from beef and pork lipids for use as additives in synthetic meat flavors and identification and quantitation of flavor volatiles extracted with SC-CO2. 

Flavor volatQes from beef and pork fat can be concentrated up to 30-fold by extracting with small quantities of SC-CO2 at low pressure. SC-CO2 concentrated volatile fractions from heated beef tallow have greater numbers of terpenoids, more high molecular weight ketones, more lactones, more esters, more phenols and more branched cyclic and unsaturated aldel des than similar extracts from heated pork fat, but the latter has more 2,4-dienals and higher concentrations of aldel des. 

Smoked meats, particularly processed pork products, show little loss of flavor and aroma after treatment. Since the storage properties of these products are usually adequate without radiation there is little point in discussing this area of endeavor. The same comment applies to cooked meats, whether they be cooked before, during, or after irradiation. 

Jensen, C., Flensted-Jensen, M., Skibsted, L.H., and Bertelsen, G. 1998. Warmed-over flavor in chill-stored pre-cooked pork patties in relation to dietary rapeseed oil and vitamin E supplementation. Z. Lebensm. Unters. Forsch. A 207 154-159. 

Poste, L.M., Willemot, C., Butler, G., and Patterson, C. 1986. Sensory aroma scores and TBA values as indices of warmed-over flavor in pork. J. Food Sci. 51 886-888. 

Role of Nitrite Sato and Hegarty (3) reported that 2000 ppm of nitrite completely eliminated WOF, while as little as 50 ppm greatly inhibited its development. Bailey and Swain (28) further confirmed the effectiveness of nitrite in preventing oxidation of fresh meat stored under refrigeration and verified its role in preventing WOF. A concentration of 156 ppm of nitrite has been shown to inhibit WOF development in cooked meat, with a twofold reduction of TBA values for beef and chicken and a fivefold reduction for pork (29). Table V also demonstrates that nitrite inhibits WOF development. Undoubtedly these results explain the higher flavor scores for nitrite as compared to NaCl-containing cured pork (30). 

It appears, then, that there is a general, meaty aroma, common to cooked beef, pork, and lamb (and probably poultry), attributable to the pyrolysis of the mixture of low molecular weight nitrogenous and carbonyl compounds extracted from the lean meat by cold water. But the aromas of roast beef, roast pork, roast lamb, and roast chicken are unmistakably different. The chemical composition of the muscular fat deposits of these animals differ appreciably, and it is to these lipid components that we must look to account for the specific flavor differences. Heating the carefully separated fat alone does not give a meaty aroma at all, much less an animal-specific one. It is the subsequent reactions of pyrolysis products of nonlipid components that give the characteristic aromas and flavors of roasted meats (20). 

Lipid decomposition volatiles. Reactions of sugar and amino acids give rise to odor profiles that are, at best, common to all cooked or roasted meats. The water soluble materials extracted from chicken, pork, or beef give reasonably similar meat flavor. To develop a species specific aroma one needs to study the lipid fraction and the volatiles produced from those lipids. The work of Hornstein and Crowe (10) reported that the free fatty acids and carbonyls generated by heating will establish the specific species flavor profiles. 

WOF is characterized sensorially as being "old, stale, rancid, metallic and painty". These flavors are highly related to concentrations of pentanal, hexanal, 2,3-octanedione and total volatiles in chicken, turkey and beef (21) and to twenty-one different oxidative volatiles in pork (22). The compounds were quantitated by the GLC/MS method of Suzuki and Bailey (23) and appear to be excellent markers for WOF. 

The flavor industry has introduced, over the years, methods of developing meat flavors by processing appropriate precursors under carefully controlled reaction conditions. As a result, meat flavors having a remarkably genuine meat character in the beef, chicken and pork tonalities are available for the food industry. It has repeatedly been stated that the Maillard reaction is particularly important for the formation of meat flavors. However, of the 600 volatile compounds isolated from natural beef aroma, only 12% of them find their origin in sugar/amino acid interactions and of these 70% are pyrazine derivatives. 

The average temperature of the pork in the frying pan was about 80°C. A period of 70-80 minutes was needed to remove nearly 75% water, and the average final water activity was 0.70. The partially dried and disintegrated pork bundle was further fried in the same frying pan to form the desired color, flavor and mouthfeel. In the final frying stage, wheat flour was added to absorb lard and coat the surface. 

Model systems composed of the seasoned pork bundle, sucrose and lard were used to investigate the effect of the frying temperature and lard content on flavor and color development in Chinese fried pork bundle. Seasoned pork bundles were prepared as described previously, except superheated steam was used to provide the various heating temperatures following the designs of Box and Behnken (1). 

As shown in Figure 2, the raw meaty odor of pork bundles decreased as the heating temperature increased, while increases in lard content had no significant effect. A possible explanation is that the raw meaty odor was covered by the flavor formed during heating. 

Frying temperature was found to be the crlterial parameter that determined the flavor quality in Chinese pork bundle. Cooked meat aroma increased as the heating temperature varied from 134°C to 172°C., as shown in Figure 3. Below 130°C neither cooked meat aroma nor brown color developed. Slightly higher temperatures have been reported for the optimum flavor formation in fried potato chips at 180°C (2), and roasted beans at 200°C (3). 

Lipids in foods vary from traces as in cereals to 30-50% as in nuts. The physical state and distribution of lipids vary considerably among food items. In each item lipid distributions affect its flavor as it undergoes chemical reactions and act as a flavor components vehicle or partitioning medium. Furthermore, lipids have a pronounced effect upon the structure of food items. Fatty acids of neutral (triglycerides) and polar lipids of beef and pork are tabulated in Table III. 

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