Quantitative Performance of a Simple Tenax‐GC Adsorption Method For Use in the Analysis of Aroma Volatiles

Abstract

A simple method for obtaining ether extracts of aroma volatiles from foods for gas chromatographic analysis using single-use Tenax-CC collection tubes is described. The method was characterized quantitatively for the collection of a variety of compounds from model systems by both dynamic-purging (10 ppb level) and equilibrium displacement techniques (15 ppm level), and for collection of fractions (250 kg level) from packed gas chromatographic columns. A range of variation in reproducibility of 5-22% was found for recovery of compounds by the dynamic purging system, and less than 10% variation was encountered for ethyl esters using the equilibrium displacement system. Collection efficiencies for selected ethyl esters from packed gas chromatography column collections were about 80% of theoretical with a variation of less than 10%.

Influence of Processing on the Volatile Compounds Characterizing the Flavor of Pickled Fish

“…As has been noted earlier for a variety of fish (Josephson et al, 1983a(Josephson et al, , 1984a, the freshly harvested smelt contained enzymically formed fresh fish alcohols in greater abundance than the carbonyls (Table 1). However, the lower thresholds exhibited by the volatile carbonyls compared to the alcohols result in dominating contributions of carbonyls to the intensity and overall odor quality of freshly harvested fish (Olafsdottir, 1985). For example, the recognition threshold for 1,5-octadien-3-one (0.001 ppb; Swoboda and Peers, 1977) is five orders of magnitude lower than that for 1,5-octadien-3-01 (10 ppb; Whitfield et al, 1982).…”

“…Approximately 1OOg fresh, unwashed, gutted and deheaded smelt were blended in 500 mL saturated NaCl with an internal standard (3.7 pg ethyl heptanoate in 50 uL ethyl ether). These samples were purged under a stream of nitrogen (2 hr, 120 mL/min; 21°C) for collection onto Tenax CC (60-80 mesh, ENKA N.V., Holland) as described by Olafsdottir et al (1985). Volatiles were eluted from each Tenax trap with 1 mL ethyl ether (Mallinckrodt Inc., Paris, KY), and concentrated to approximately 10 pL under a stream of nitrogen.…”

Antioxidant Protection of Bulk Fish Oils by Dispersed Sugars and Polyhydric Alcohols

“…Volatile compounds in fish oil emulsions were quantitatively measured using the dynamic headspace procedure described by Olafsdottir et al (12).…”

Rapid Preconcentration and Enrichment Techniques for the Analysis of Food Volatile. A Review

“…After adsorption onto a sorbent, the trapped compounds are desorbed by heating and then cryofocused at the head of the GC-column (for cryofocusing methods, see Kolb, 1999). The analytes can also be eluted with a solvent (Olafsdottir et al, 1985;Burger and Munro, 1987;Rizzolo et al, 1992;Krumbein and Ulrich, 1996), but recovery is not always satisfactory (Boren, 1985). In addition, thermal desorption shows the following advantages: (i) analysis of 100% of the trap content (instead of an aliquot part), (ii) no solvent peak, (iii) no waste and (iv) no contamination from solvent.…”