Volatile components of crayfish processing waste were analyzed by dynamic headspace/capillary gas chromatography/mass spectrometry and chromatography-coupled aroma perception analysis with simultaneous photoionization detection. One hundred seventeen compounds were identified. The majority of the flavor compounds previously identified in freshly boiled crayfish tail meat and hepatopancreas also were detected in crayfish waste. Many areas in the headspace profile contained good nutty, green woody, sweet fruity and very desirable salty meaty aromas, indicating the presence of important crayfish flavor components in the sample.

A rapid microscale steam distillation/ solvent extraction procedure was used to extract parts per billion (nanograms per gram) levels of a "popcornMike aroma compound, 2-acetyl-l-pyrroline, from milled aromatic rice (Oryza sativa, L.) samples. Improvements on the gas chromatographic separation and mass spectrometric sensitivity and specificity in the selected ion monitoring mode required only 1 g of rice for each analysis. Selected aromatic rice samples, including Della, Basmati 370, and Jasmine, were found to contain 2-acetyl-l-pyrroline in the range 76-156 ppb on the basis of equivalent weight of an internal standard, 2,4,6-trimethylpyridine, and dry weight of rice.

The volatile flavor components of steamed rangia clam (Rangia cuneafa) were extracted by dynamic headspace sampling (DHS) and simultaneous distillation/extraction (SDE) techniques, and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC-coupled aroma perception. Twenty-two heterocyclic aroma compounds were identified. Volatile flavor compounds in other chemical classes, such as aldehydes, alcohols, ketones, and terpenes, also were identified. The unique clam aromas were contributed by a combination of S-, and N-containing compounds and ketones. In general, sampling methods (DHS and SDE) complemented each other in compounds detected in the sample. However, SDE gave more information on characteristic steamed clam flavors. INTRODUCTIONLOUISIANA is a major seafood producing state including shrimp, crab, crayfish, and oyster. Less known is the abundance of rangia clam (Rangia cuneata), about 50 billion, in Louisiana brackish waters (LaSalle and de la Cruz, 1985). These clams have a musty/earthy off-flavor problem that limits their commercialization for food use. The compound responsible for this off-flavor has been identified as geosmin (trans-1, IO-dimethyl-trans-9-decalol) by . Several off-flavor reduction approaches including relaying, depuration, and feeding clams with non-geosmin producing algae have been proposed (Rusch et al., 1988). Despite the off-flavor,

Restructured beef roasts containing 0.3% sodium tripolyphosphate (SIT) and 1% soy protein isolate (SPI); or STP only; or SPI only; or no STP or SPI were cooked at 70 or 100°C to an internal temperature of 65"C, then stored at 4°C for 0 and 3 days. In control roasts, the higher cooking temperature resulted in higher (p 5 0.05) TBA values. STP and SPI inhibited oxidation but the effect was not detected sensorially. Significant interactions (p 5 0.05) indicated that STP was more effective at higher cooking temperatures and SPI at lower temperatures. Total moisture of the cooked product was significantly greater with STP but no differences in juiciness and tenderness were detected sensorially.

The concentration of geosmin was determined in freshly dredged and 2-wk relayed rangia clam (Rangin cuneata) samples in different seasons of the year. Vacuum distillation/solvent extraction using an internal standard was followed by multiple-level standard addition gas chromatography/selective ion monitoring mass spectrometry. Most coefficients of variation were lower than 10%. On a dry-weight basis, the gcosmin level in dredged clams was highest (343 rig/g)) in August and averaged 51.6 ngIg in other months. A 52% reduction of geosmin was found after two week relaying during the period of May-June. However, only 1% reduction of geosmin was observed during February-March.