RESUMEN
Premature browning (PMB) was investigated in ground beef patties with (0.04%, w/w) and without erythorbate. In Experiment 1, patties were stored at 4 °C for 48 h; at -18 °C for 21 days; or at -18 °C for 21 days, thawed at 4 °C for 24 h; and cooked. Bulk ground beef was stored at -18 °C for 24 days, thawed for 24 h at 4 °C, and patties prepared and cooked immediately. In Experiment 2, fresh patties were overwrapped with oxygen-permeable film or packaged in 80% O(2)/20% N(2) (MAP), and stored for 48 h at 4 °C, or at -18 °C for 21 days, and cooked. Total reducing activity and color (L*, a* and b* values) were measured immediately prior to cooking. Patties were cooked to internal temperatures of 60, 66, 71 and 77 °C and internal cooked color was measured. Total reducing activity was higher for the erythorbate treatment than controls for all storage conditions (P<0.05). a* Values of cooked patties were higher for erythorbate than control treatments under all storage and packaging conditions at 60 and 66 °C (P<0.05). The presence of erythorbate in ground beef patties appeared to maintain red color at cooked internal temperatures of 60 and 66 °C. Frozen bulk storage appeared to increase the susceptibility of ground beef to PMB when compared to fresh and frozen patties. Patties cooked directly from frozen state appeared less susceptible to PMB than frozen-thawed and bulk storage. Ground beef appeared predisposed to PMB when stored in high-oxygen MAP at 4 °C for 48 h.
RESUMEN
Our objective was to evaluate the antioxidant capabilities of clover (CH) and wildflower honeys (WH) in delaying lipid oxidation in cooked and reheated ground beef patties stored in refrigerated and frozen states. CH and WH (5%, 10%, or 15% w/w) were each mixed separately into ground beef chuck (18% fat) and formed into 30g patties mixed with 1% salt (w/w). A control (CON) with no honey and a control with sodium tripolyphosphate (STP; 0.25% w/w) were used for comparison. Patties were cooked to 71°C, overwrapped with oxygen-permeable PVC film and either stored refrigerated (4°C) for 12 days or frozen (-18°C) for 45 days. Cook yield, pH and water activity were measured on day 0. On designated sampling days, patties were reheated to 71°C. Thiobarbituric acid-reactive substances (TBARS) and lipid hydroperoxides (LOOH) were measured spectrophotometrically to assess lipid oxidation. TBARS and LOOH of ready-to-eat (RTE) ground beef patties containing either CH or WH were lower (P<0.01) than CON patties following storage; however, STP patties had lower TBARS values than honey-containing patties (P<0.01). WH and CH at 15% were equally effective in suppressing LOOH compared to STP in refrigerated and frozen patties. All honey concentrations improved cook yield, with 10% WH being more effective than STP. Both CH and WH delayed lipid oxidation in RTE ground beef patties stored at 4°C and -18°C, with WH decreasing LOOH formation in refrigerated patties as effectively as STP. Honey may be a natural alternative to phosphates to delay lipid oxidation.
RESUMEN
Premature browning (PMB) describes cooked beef that may appear done before reaching 71 °C. Ground beef from paired Longissimus lumborum (LL) and Psoas major (PM) muscles was formed into patties. Patties were cooked immediately, and after 48 and 96 h storage at 4 °C. Total reducing activity (TRA) and external color were measured immediately prior to cooking. Patties were cooked to internal end point temperatures of 60, 66, 71 or 77 °C and internal cooked color (L(*), a(*) and b(*) values) was measured. Raw PM patties had greater L(*) values and lesser a(*) values than those from LL (P<0.05). For LL and PM, raw a(*) and b(*) values decreased with storage from 0 h to 96 h (P<0.05). At 0 and 48 h storage, cooked patties prepared from PM had greater a(*) values than those prepared from LL at all internal endpoint temperatures (P<0.05). Internal cooked a(*) values of patties from PM decreased with storage of raw patties, whereas it was stable for LL patties (P<0.05).