Analysis of Volatile Flavor Components in Steamed Rangia Clam by Dynamic Headspace Sampling and Simultaneous Distillation and Extraction

Abstract

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,

Effect of dietary lipid sources on odour‐active compounds in muscle of turbot (Psetta maxima)

“…This compound has been previously reported as one of the most odorous in mussels 36 and clams. 37 Prost et al 23 showed that (E)-2-penten-1-ol contributed partially to the aroma of farmed turbot. (E)-2-Hexen-1-ol was perceived by six, seven and six judges in extracts of ®sh fed FO, SO and LO diets respectively and exhibits a green and moss-like odour.…”

Identification of odour‐active compounds in muscle of brown trout (Salmo trutta) as affected by dietary lipid sources

“…This compound, which is characterised by a cucumber-like odour, has been described as an odorous compound in ®sh and other seafood products. 9,10,15,16,32 According to Milo and Grosch, 36,37 (E,Z)-2,6-nonadienal contributes strongly to the odour of brown trout and cod. Hirano et al 6 described it in ayu as the most important odorous compound, contributing to the cucumber odour of this ®sh.…”

Chemical and Sensory Changes in Flavor of Roux Prepared from Wheat Flour and Butter by Heating to Various Temperatures

“…Chemical analysis A 1-L round flask containing each roux sample prepared from 60 g of materials, 440 ml of purified water and 0.5 ml aqueous solution of 0.25 mg/ml internal standard (tridecane or 2,4,6-trimethyl pyridine) was attached to a rotary evaporator (Tanchotikul & Hsieh, 1991). The volatile components from each roux sample (roux 0-V) were collected by steam distillation under reduced pressure (20-24 mm of Hg) at 50˚C for 100 min (Kato, 1992).…”