Effects of brine temperature on ham and bacon processing characteristics
Prior to the invention of refrigeration, the addition of salt during meat processing was used for meat preservation. Present day, cured meats have a combination of salts and sodium nitrite that will inhibit most psychrophilic flora (spoilage bacteria) thus increasing shelf life of products. Thermal processing of meat products to an internal temperature of 65˚C to 77˚C is sufficient enough to kill most harmful microorganisms. Brine chillers are used in industry to keep cure at a cool, constant temperature. If brine temperature exceeds 10˚C, along with the addition of erythorbate, there will be a rapid reduction of nitrite to nitric oxide gas which will escape before brine injection. With brine temperatures below 10˚C, the reduction of nitrite to nitric oxide to nitrosylhemochrome will remain in the brine without evaporation, allowing a greater amount of nitrite in the brine available to cure the meat. Research has been conducted at the University of Arkansas on the effects of brine and ham temperature on injection yield, instrumental color, tenderness, and sensory characteristics of cured hams; however, no research has been conducted on the effects of brine temperature on ham and bacon processing and sensory characteristics. Therefore, two experiments were conducted to evaluate the effects of brine temperature on ham and bacon processing characteristics as well as an additional experiment designed to test the effects of a brine and ham temperature combination on processing characteristics. The objective of these experiments was twofold: 1) evaluate the effects of brine temperature on ham and bacon processing characteristics and 2) evaluate the effects of brine temperature and meat temperature on ham processing characteristics. For this set of experiments, a total of 170 pork knuckles and 60 pork bellies were used to evaluate the effects of brine temperature. In the first ham experiment, 111 ham knuckles and 60 bellies were randomly allotted to 1 of 3 brine treatment groups; 1) -1˚C (Cold), 2) 7.2˚C (Average), or 3) 15˚C (Warm). For the second portion of the experiment, 59 of the 170 ham knuckles were randomly allotted to 1 of the 3 same brine treatment groups as the previous experiment. However, each of the knuckles were tempered to equal the brine temperature in which they were allotted. In the first experiment (brine temperature with equal temperature hams), processing characteristics including initial weight, pumped weight, drained pumped weight, initial pump uptake percentage, drained pump uptake percentage, cooked weight, cooked yield, and chilled weight did not differ (P ≥ 0.32) among treatments. A trending dif teference (P = 0.06) occurred among treatments for evaporative chill loss percentage. Instrumental color differed (P < 0.02) among treatments with a 1.2 unit greater L* (lighter color) value for warm, however, the magnitude of difference was not great enough for consumers to notice a difference. A trending difference (P = 0.07) was detected for a* values, and no differences were detected in b* values. No differences were detected in moisture or extractable lipid content among brine temperature treatments. A trending difference (P = 0.07) was detected in springiness values, although there were no differences for hardness, fracturability, cohesiveness, chewiness, or resilience among treatments. No differences were observed for sensory characteristics among brine temperatures. The second experiment (brine temperature and bacon processing) produced no differences among any processing characteristics, proximate analyses, or sensory characteristics for bacon. The third experiment (brine and ham temperature at equal temperatures) produced many differences in processing characteristics including pumped weight (P = 0.01). Knuckles designated as Average and Warm temperatures were 0.15 kg heavier than knuckles designated as Cold. Similarly, initial and drained pump uptake percentage of the Average and Warm knuckles were 14% and 10% greater (P < 0.0001) than knuckles designated as Cold. Cooked weights of Cold hams were 0.12 kg less (P = 0.04) than Average temperature hams, but neither were different (P ≥ 0.16) from Warm hams. Cooked yield percentage was 10% less (P < 0.0001) in Cold knuckles compared with Average and Warm hams. Chilled ham weight was 0.13 kg less (P = 0.02) in Cold hams compared with Average hams, but neither were different (P ≥ 0.13) from Warm hams. Initial weight and evaporative chill loss percentage were not different (P ≥ 0.05) among treatments. Cold hams tended (P = 0.10) to have 1.10 greater L* (lighter) than Warm hams, but neither were different (P ≥ 0.24) from Average hams. Instrumental yellowness (b*) of Cold hams was 0.7 units greater (more yellow, P < 0.001) than Average and Warm hams. However, a* values did not differ among treatments. Differences (P < 0.0001) were detected for percent moisture, with a trending difference (P = 0.06) for extractable lipid content. No differences (P > 0.21) were detected for hardness and fracturability among treatments, a trending difference (P ≤ 0.09) was observed for springiness and chewiness, and a difference (P ≤ 0.03) was observed for cohesiveness and resilience. Overall, brine temperature did not affect ham or bacon processing characteristics when meat temperature was held constant. However, when meat temperature is manipulated to be equal with brine temperature, several processing characteristics, including initial pump uptake, are affected. However, food safety becomes an issue as meat temperature is increased. Overall, when meat temperature is held at refrigerated temperatures, brine temperature did not influence processing characteristics.
University of Illinois - Urbana-Champaign
Networked Digital Library of Theses and Dissertations
University of Illinois at Urbana-Champaign