Arthur M. Spanier

The effect of post-mortem aging on meat flavor quality in Brangus beef. Correlation of treatments, sensory, instrumental and chemical descriptors

The flavor of muscle foods is dependent upon factors such as the animals age, breed, sex, nutritional status and manner of cooking. Most important to the final flavor of the meat is relative age in the post-mortem aging process as it is during this time that many chemical flavor components are formed (Spanier et al., 1990). These components serve either directly as flavor components or as a pool of reactive flavors and intermediates that form many of the characteristic meat flavors after cooking. The post-mortem aging process is identified with enhancement of beef sensory quality due to enhanced tenderization. While this is true for beef texture, it is not true for the overall flavor of meat. Data is shown indicating that, during post-mortem aging, desirable flavors such as beefy, brothy, browned-caramel, and sweet decline while off-flavors such as bitter and sour increase.

Unraveling the secret of meat flavor

Abstract Meat flavor arises from the complex interactions among amino acids, peptides, sugars, thiamine, metabolites of nucleotides, lipids and products of lipid oxidation. Previous research on meat flavor has shown numerous volatile compounds to be involved in meat aroma but the identities of specific mixtures of compounds contributing to individual meat flavors are not fully known. Factors that exert significant influence on meat flavors such as the nutritional status of the animal, the animal species and the temperature at which the meat is cooked are discussed. Lastly, it is suggested that the analytical procedures and the interpretation of the data arising from such analyses of meat flavor volatiles may be hindering rather than contributing to our understanding of meat flavor.

Isolation, purification, and alteration of some functional groups of major milk proteins: A review

This review covers selected methods of isolation and purification of mainly alpha s-casein, beta-casein, kappa-casein, beta-lactoglobulin, and alpha-lactalbumin. Selected methods of alteration of some functional groups of these proteins also were reviewed. Isolation and purification of milk proteins per se are methods of modifying the individual milk proteins. Gram quantities of these proteins can now be purified in a relatively short time using ion-exchange resins. Due to the prominent use of non-food-grade reagents in the procedures for preparation of these milk proteins, individual proteins are not maximally utilized for the manufacture of food/feed and pharmaceutical products. Therefore, intensive research efforts are needed to obviate the problems associated with underutilization of milk proteins.

Preparative separation of value-added peptides from rice bran proteins by high-performance liquid chromatography

Abstract Peptides from rice bran protein were investigated because of their potential usefulness in industrial food uses. Peptides were generated from defatted rice bran by treatment with a commercial protease to 7.6% peptide bond hydrolysis. Protein hydrolysates were separated into 20 peaks by quaternary methylamine anion-exchange HPLC on a 25 mm×30 cm column with 96% recovery. Out of 12 peptide fractions, the first four contained 37 and 57% of the total protein and amide in the hydrolysate, respectively. Since glutamic acid in peptides is a potent flavor enhancer, these peptides can serve as an excellent source of flavor enhancing ingredients after further deamidation. An HPLC method was developed for the potential commercial scale-up preparation of these functional peptides for food use leading to new value-added products from the under-utilized rice bran.

Meat flavor: contribution of proteins and peptides to the flavor of beef.

While the majority of meat flavor is lipid in origin, the contribution of peptides and amino acids to overall meat flavor should not be overlooked. Amino acids and peptide levels have been shown to change with postmortem aging in muscle and with dry-curing, a process similar to PMA. Variation in protein, peptide, and amino acid composition have also been shown to occur with heating and with post-heating storage of meat. This makes a large pool of reactive components that may directly affect flavor or indirectly affect flavor by reacting with reducing sugars to form Maillard reaction products and Strecker degradation products that impact meat flavor. Further research in this area should continue with particular emphasis on natural peptide flavor enhancers, modulators, and potentiators.

Fresh-cut pineapple (Ananas sp.) flavor. Effect of storage*

Abstract Fresh-cut fruits are the fastest growing market in todays produce business. However, once a fruit is cut it becomes a different product from what it was in its uncut form. Thus, produce marketers must ensure their products flavor and texture as well as the products safety. We examined the effect of storage (4°C for 3, 7, and 10 days) on the flavor volatile profile of freshly-cut pineapples. Volatiles of fresh-cut and stored pineapple chunks were examined by gas chromatography (GC), GC olfactometry (GC-O), GC mass spectroscopy (GC-MS), and microbiological testing. GC-O data using dynamic headspace sampling techniques indicated that pineapple-like flavors increased very slightly during storage while unpleasant odors and volatiles such as fermented, cheesy, sour dough, alcohol, oily, etc., showed dramatic increases and masked the more desirable pineapple flavor. The large increases in the level of low boiling alcohols (as determined by GC and GC-MS) in stored pineapple suggest that fermentation events were ongoing. Yeast were confirmed as the source of the fermentation derived alcohols. No other microbes (aerobic plate counts, total coliforms, E. coli, and mold) were found above the range acceptable to the fresh-cut produce industry.

Effect of temperature on the analysis of beef flavor volatiles: Focus on carbonyl and sulfur-containing compounds

This paper demonstrates that the volatile flavor profiles from cooked and cooked/stored ground beef are directly affected by and related to the purge temperature for volatile isolation. Minimal analytical efficacy and recovery are seen when the samples are purged at 50°C. This is thought to arise from inefficient extraction of flavor volatiles. Different and potentially misleading chromatographic profiles are obtained when the samples are purged at 100°C. This response is thought to be due to conversion of one volatile species to another. Optimal extraction and limited conversion of the volatiles are seen at a temperature of 75°C. The data clearly suggest that a more accurate picture of food volatile composition and, therefore, potential flavor can best be appreciated by a thorough examination and understanding of the effect of temperature on the development and content of these volatile mixtures.

Flavor Differences due to Processing in Dry-Cured and Other Ham Products Using Conducting Polymers (Electronic Nose)

The origin of salting, originally used to preserve meat products in general, is lost in ancient time. However, Caton, in “De Re Agricola,” described several salted-meat recipes that today are still being used in several Mediterranean areas (Pineda, 1989). With today’s widespread availability and use of refrigeration, salting of meat for preservation has become of less importance. Today, salting has been modified and improved to dry-curing wherein additives and adjuncts such as nitrates and ascorbic acid are added to the salt; furthermore, processing time is for a long periods to permit optimal maturation and flavor development (Flores and Toldra, 1993).

Use of Electronic Nose Technology to Examine Apple Quality

Apples, traditionally an ethnic food, have become a globally desired food commodity. According to Smock and Neubert (1950), “the original home of the apple (Malus sylvestris is not know but it is thought to be indigenous to the region south of the Caucasus, from the Persian province of Ghilan on the Caspian Sea to Trezbizond on the Black Sea.)” Apples have probably existed from prehistoric times in both the wild and cultivated states in Europe from the Caspian Sea to the Atlantic Ocean (Hulme and Rhodes, 1971). Apples were available as early as 100. B.C., but “Pearmian” appears to be the first variety recorded in history appearing in 1204 in a deed relating to the lordship of Runton in Norfolk. In America, there are records as early as 1647 of apples having been grafted on seedling rootstocks in Virginia. By 1773, three years before the American War for Independence, apples from America were found in the London markets. The spread of the cultivation of apples in the United States is ascribed to Johnny Appleseed (John Chapman) who established nurseries in Pennsylvania and Ohio.