58-1 |
The release of acids from a high-fat system |
K. A. HOUSE, E. H. Lavin, and T. E. Acree. Dept. of Food Science & Technology, Cornell Univ., W. North St., NYSAES, Geneva, NY 14456 The volatile composition of the aroma released from food during eating (retronasal aroma) differs from the volatile composition of the static headspace of that food. In order to more accurately simulate the composition of the headspace volatiles released from cheese during eating, the Retronasal Aroma Simulator (RAS) was used. The RAS accounts for mastication, salivation, body heat, and breathing. It produces a dynamic non-equilibrium headspace from which volatiles that are released are swept and collected. The most potent acids identified in cheddar cheese (acetic, butanoic, hexanoic, octanoic, decanoic, and dodecanoic acids) were added to a system containing soybean oil and artificial saliva at concentrations they naturally occur in cheese. The model system was sampled in the RAS. Volatile compounds were simultaneously trapped on three different Solid Phase Microextraction (SPME) fibers (Polyacrylate, Carbowax/Divinylbenzene, Polydimethylsiloxane/Divinylbenzene) then desorbed into a Hewlett Packard Gas Chromatograph/Mass Spectrometer, equipped with a HP1701 column. Compounds were identified based on their retention time and mass spectra. All acids were detected except for decanoic acid and dodecanoic acid. Similar results were found when samples of NY State Cheddar cheese (mild, sharp, and extra sharp) were sampled in the RAS, suggesting that decanoic and dodecanoic acids are released from high fat food systems below detection thresholds. In order to determine the sensory impact of each acid, a descriptive analysis test was conducted using a model cheese with omission testing (N-1). Panelists described the aroma of the model cheese by sniffing the cheese (orthonasal aroma) and after eating the cheese (retronasal aroma). By removing acids one at a time, the impact of each acid on the overall flavor was determined.
Session 58, Food Chemistry: Lipids, Emulsions and Antioxidants
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