Date of Award
Doctor of Philosophy
Food Science and Technology
Sharon Melton, John Hitchcock
Fresh, post-rigor pork was formulated to 42% fat and ground through a 4 mm plate. One half of the treatment was seasoned with a commercial spice mix which contained a mixture of butylated hydroxytoluene and butylated hydroxyanisole (BHT/BHA) at 200 ppm and the other half with rosemary oleoresin (200 ppm). Each treatment was stuffed into a natural casing to produce sausage links (SL). A Wearever Impinger Oven was used to cook one half of the treatments and a multipurpose oven (MPO) was used on the other. After leaving the oven, initial cooking yields and temperatures were recorded. The SL were stored for either 0, 45 or 90 d. Reheating yields, Warner-Bratzler shear, lipid and moisture percentages of reheated SL and thiobarbituric acid values (TBA) were determined for each treatment. A sensory panel which had received 6 h of orientation scored the SL at each storage period on the attributes of tenderness, juiciness, flavor and intensity of warmed over flavor (WOP). Flavor volatiles, collected on 0 and 90 d stored samples using simultaneously distillation extraction, were analyzed qualitatively by gas chromatography (GO/mass spectroscopy and quantitatively by GC/flame ionization.
The impingement oven had superior initial cooking yields for SL as compared to the MPO SL, This difference appeared to be due to less lipid loss The greater lipid retention may have been due to dehydration of the natural casing which may have served as a superior barrier and/or less cooking time in the impingement oven. The impingement cooked SL also tended to have higher Warner-Bratzler shear force values and were perceived by panelists as tougher than the MPO SL. Reheating yields were lower for the impingement 5L than the MPO cooked SL. No differences were found for WOF, flavor, juiciness or reheated moisture and lipid percentages between ovens.
The rosemary oleoresin SL were perceived as having a hotter flavor than the BHT/BHA SL. This may be due to a concentration of spices caused by a dispersion problem with the rosemary oleoresin. In addition, panelists made comments about a sage flavor note in rosemary SL. This sensation may have been scored as hotter on the flavor scale. Finally, the difference may have been due only to a formulation error at the production facility. The rosemary oleoresin was as effective as the BHT/BHA SL up to 45 days storage for retarding WOF. As would be expected, no consistent differences were found for tenderness, juiciness, reheated lipid percentages or reheating yields between antioxidants.
As expected, oxidative rancidity was highest at 90 days storage. Moisture percentages of reheated SL were lowest at 90 d storage and the inverse was true for lipid percentages. This is most likely due to a dehydration of the SL during storage. Reheating yields were lower for 90 d SL.
No differences in relative percentages of volatiles were found between SL cooked in the impingement oven compared to those in the MPO. More camphene, α-pinene, β-pinene and camphor were found in the rosemary oleoresin SL than in the BHT/BHA SL. Hexanal, as been reported in the literature as being associated with WOF development, increased In concentration with increasing storage; however. In contrast to other reported findings T,T-2,4 heptadienal decreased at 90 d.
Bacon, Craig D., "Effect of cooking method, antioxidant and storage on sensory characteristics and flavor volatiles of precooked sausage links. " PhD diss., University of Tennessee, 1990.