Anti-oxidant effect of extracts of kinnow rind,pomegranate rind and seed powders in cooked goat meat patties

To overcome the disadvantages of using synthetic anti-oxidants in meat products, an investigation was carried out to evaluate the anti-oxidant effect of extracts of fruit by-products viz., kinnow rind powder (KRP), pomegranate rind powder (PRP) and pomegranate seed powder (PSP) in goat meat patties. Total phenolics content, DPPH radical scavenging activity and effect of these extracts on instrumental color, sensory attributes and TBARS values during storage (4 ± 1 °C) of goat meat patties were evaluated. Results showed that these extracts are rich sources of phenolic compounds having free radical scavenging activity. Hunter Lab L value significantly (P < 0.05) lowered in PRP followed by PSP and KRP patties. Sensory evaluation indicated no significant differences among patties. Further, a significant (P < 0.5) reduction in TBARS values (lipid oxidation) during storage of goat meat patties was observed in PRP, PSP and KRP as compared to control patties. Average TBARS values (mg/kg meat) during refrigerated storage (4 ± 1 °C) were significantly lower in PRP, followed by PSP and KRP as compared to control. The overall anti-oxidant effect was in the order of PRP > PSP > KRP. It was concluded that extracts of above fruits by-product powders have potential to be used as natural anti-oxidants in meat products.     

Antioxidative effect of dietary grape pomace concentrate on lipid oxidation of chilled and long-term frozen stored chicken patties

Grape pomace concentrate (GPC) is a natural source of phenolic compounds with high antioxidant capacity. The effect of a diet containing GPC on lipid peroxidation levels (TBARS) and antioxidant capacity (ABTS method) of raw and cooked chicken breast meat patties stored in chilled conditions (4 °C) for 0, 3, 6, 13 and 20 days, and long-term frozen storage (6 months) was investigated. Chickens were fed GPC at levels of 0, 30 and 60 mg/kg from 3 to 6 weeks of age. Dietary GPC did not affect chicken performance. Lipid oxidation (TBARS value) was significantly increased by the storage time (0–20 days and 6 months of storage, respectively) in raw and cooked samples. Dietary GPC significantly caused an inhibitory effect on lipid oxidation of raw and cooked breast chicken patties compared with samples obtained from birds fed the control diet at 20 days and long-term frozen storage (6 months). Radical scavenging capacity was significantly increased at 20 days in cooked samples and significantly reduced at 6 months of storage in raw and cooked samples. The higher concentration of dietary GPC increased the ABTS values only in the raw samples. These results indicated that dietary grape pomace concentrate could be effective in inhibiting lipid oxidation of chilled and long-term frozen stored chicken patties.     

Antioxidative activity of carnosine in gamma irradiated ground beef and beef patties

The activity of carnosine as a natural antioxidant in gamma irradiated ground beef and beef patties was studied. Samples of ground beef, in the absence and presence of 0.5% or 1.0% carnosine, as well as raw and cooked beef patties prepared with 1.5% salt (NaCl), in the absence and presence of 0.5% or 1.0% carnosine, were gamma irradiated at doses of 0, 2, and 4 kGy. The extent of oxidation in irradiated and non-irradiated samples of ground beef and raw beef patties was then determined during refrigerated (4 ± 1 °C) and frozen (−18 °C) storage, while determined for cooked beef patties during refrigerated storage only. Moreover, the determination of metmyoglobin (MetMb) accumulation and sensory evaluation for the visual color were carried out for samples of ground beef and raw patties. The results indicated that salt or salt and cooking accelerated the oxidative processes and significantly increased the peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) in the prepared non-irradiated samples. However, salt slowed down the accumulation of MetMb in raw patties. Irradiation treatments and storage in the absence of carnosine significantly (P < 0.05) increased the PV and TBARS in samples, at higher rates in salted or salted and cooked beef. Moreover, irradiation and storage significantly (P < 0.05) increased the formation of MetMb in ground beef and raw patties in the absence of carnosine. Addition of carnosine significantly (P < 0.05) reduced the oxidative processes and MetMb formation (proportionally to the used concentration) in samples post-irradiation and during storage. Furthermore, carnosine exerted significant efficacy in maintaining an acceptable visual red color post-irradiation and during storage of ground beef and raw patties. These results demonstrate that carnosine can be successfully used as a natural antioxidant to increase the oxidative stability in gamma irradiated raw and cooked meat products.     

Effects of lactate and modified atmospheric packaging on premature browning in cooked ground beef patties

Our objectives were to determine the effects of lactate and modified atmosphere packaging on raw surface color, lipid oxidation, and internal cooked color of ground beef patties. Eight chubs (85% lean) were divided in half and each half was either assigned to the control (no lactate) or mixed with 2.5% lactate (w/w). Following treatment, patties were prepared and packaged in either vacuum, PVC (atmospheric oxygen level), high-oxygen (80% O₂ + 20% CO₂), or 0.4% CO (30% CO₂ + 69.6% N₂) and stored for 0, 2, or 4 days at 2 °C. After storage, raw surface color and lipid oxidation were measured and patties were cooked to either 66 °C or 71 °C. Lactate improved (p < 0.05) color stability of PVC, high-oxygen, and vacuum packaged raw patties, but had no effect (p > 0.05) on the a∗ values and visual color scores of patties in 0.4% CO. Lactate decreased (p < 0.05) lipid oxidation in all packaging atmospheres. Nevertheless, high-oxygen and PVC-packaged patties had more (p < 0.05) lipid oxidation than patties in CO and vacuum. Lactate had no effect (p > 0.05) on premature browning, whereas patties packaged in high-oxygen demonstrated premature browning. Conversely, cooked patties in 0.4% CO and vacuum were more red (p < 0.05) than both high-oxygen and PVC-packaged patties. Although lactate improved raw color stability, it did not minimize premature browning in cooked ground beef patties.     

Quality evaluation of beef patties formulated with bambara groundnut (Vigna subterranean L.) seed flour

This study evaluated composite beef–bambara groundnut (Vigna subterranean L.) seed flour patties to determine the effect of bambara groundnut flour (BGF) inclusion on the quality and acceptability of the products. The effect of different levels of BGF (0%, 2.5%, 5.0% and 7.5%) on the proximate composition and pH indicate that BGF had no significant (p ? 0.05) effect on moisture, protein and carbohydrate of raw patties except ash and pH whereas there was significant (p ? 0.05) effect on all the parameters for the cooked patties. BGF significantly (p ? 0.05) reduced the shrinkage of the cooked patties from 9.13% to 6.76%, while percentage cooking yield, moisture retention, and fat retention increased significantly (p ? 0.05) with increasing BGF levels from 79.1% to 87.2%, 67.51% to 78.05% and 73.51% to 88.34%, respectively. The use of BGF significantly (p ? 0.05) increased the pH of cooked patties from 6.16 to 6.23. Beef patties extended with BGF up to 5% addition exhibited good quality attributes most acceptable to the consumers. The pH of the 0% BGF–beef patties decreased significantly during storage, up to day 14, and increased thereafter. However, the pH of the patties with BGF consistently decreased significantly up to day 21. The TBA values of both (0% and 5% BGF–beef patties) increased significantly (p ? 0.05) from 0.054 to 0.25 and from 0.05 to 0.24 mg malonaldehyde/kg, respectively. All sensory attributes decreased significantly (p ? 0.05) as storage time progressed. The physico-chemical, microbiological and sensory characteristics of the patties were found to be acceptable after 21 days refrigerated storage.     

Effects of potassium lactate,sodium metasilicate,peroxyacetic acid,and acidified sodium chlorite on physical,chemical, and sensory properties of ground beef patties

Beef trimmings were treated with 3% potassium lactate (KL), 4% sodium metasilicate (NMS), 0.02% peroxyacetic acid (PAA) or 0.1% acidified sodium chlorite (ASC) or left untreated (CON). Beef trimmings were ground, pattied, and sampled for 7 days. Under simulated retail display, instrumental color, sensory characteristics, TBARS, pH, and Lee–Kramer shear force were measured to evaluate the impact of the treatments on the quality attributes. The NMS and PAA patties were redder (a^∗, P < 0.05) than CON on days 0–3. Panelists found KL, NMS, PAA, and ASC patties to have less (P < 0.05) or similar (P > 0.05) off odor to CON on days 0–3. The NMS and PAA treated patties had lower (P < 0.05) lipid oxidation than the CON at days 0, 3, and 7. Therefore, KL, NMS, PAA, and ASC treatments on beef trimmings can potentially improve or maintain quality attributes of beef patties.     

Antioxidant activity of pomegranate rind powder extract in cooked chicken patties

The radical scavenging activity, reducing power and phenolic composition of pomegranate rind powder extract (RP) were determined and antioxidant properties of RP was evaluated in cooked chicken patties compared with vitamin C (VC) during refrigerated storage. Freshly minced chicken meat were assigned to one of the following six treatments: control (meat without any antioxidant); RP 5, RP 10, RP 15 and RP 20 (5, 10, 15 and 20 mg equivalent RP phenolics 100 g^?1 meat, respectively) and VC 50 (50 mg VC 100 g^?1 meat). The RP exhibited significantly (P < 0.05) higher reducing power and 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity. Incorporation of RP into chicken patties significantly (P < 0.05) reduced the HunterLab L* values compared with control and VC patties. Total phenolic content (as tannic acid equivalent) significantly (P < 0.05) increased from 308 in control to 441 μg g^?1 in RP 20 patties. Addition of RP to chicken patties did not affect any of the sensory attributes. The values of thiobarbituric acid reactive substances were significantly (P < 0.05) reduced from 1.530 in control patties to 0.135 mg malonaldehyde kg^?1 samples in RP patties. Pomegranate rind powder extract treatment (RP 10, RP 15 and RP 20) substantially inhibited (P < 0.05) lipid oxidation in cooked chicken patties to a much greater extent than VC treatment. Therefore, pomegranate rind powder can be utilized as an excellent natural antioxidant source.     

Effect of a brown seaweed (Laminaria digitata) extract containing laminarin and fucoidan on the quality and shelf-life of fresh and cooked minced pork patties

A spray-dried seaweed extract containing laminarin (L, 9.3%) and fucoidan (F, 7.8%) (L/F extract) from brown seaweed (Laminaria digitata) was added directly to minced pork (M. longissimus dorsi) (LD) at levels of 0.01%, 0.1% and 0.5% (w/w). Fresh and cooked minced pork patties were stored in modified atmosphere packs containing 80% O₂:20% CO₂ and 70% N₂:30% CO₂, respectively, for up to 14 days at 4 °C. The L/F extract reduced the surface redness (‘a*’ values) of fresh patties as a function of concentration. The L/F extract (0.5%) exerted the greatest lipid pro-oxidant activity in fresh patties. The L/F extract (0.5%) significantly decreased (P < 0.05) lipid oxidation in cooked patties. The L/F extract had no effect on the microbiological status, pH, water holding capacity (WHC) or cook loss of patties. Pork patties containing 0.01% L/F were preferred by sensory panellists. Further research will focus on the use of refined purified seaweed extracts in functional meat products.     

Evaluation of the antioxidant activities and nutritional properties of ten edible plant extracts and their application to fresh ground beef

In this study, we assessed the antioxidant efficacy and nutritional value of 10 leafy edible plants and evaluated their potential as natural antioxidants for meat preservation. We measured total phenolic content, 2,2-diphenyl-1-picryl-hydrazil (DPPH) radical scavenging activity, and vitamin C, chlorophyll, and carotenoid contents of 70% ethanol and water extracts of the edible plants. Based on these results, we investigated the effects of butterbur and broccoli extracts on lipid oxidation in ground beef patties. Plant extracts and butylated hydroxytoluene (BHT) were individually added to patties at both 0.1% and 0.5% (w/w) concentrations. Thiobarbituric acid reactive substance (TBARS) values and color parameters were tested periodically during 12 days of refrigerated storage. TBARS levels were significantly lower (p ≤ 0.05) in the samples containing plant extracts or BHT than the non-treated control. In addition, the beef patties formulated with the selected plant extracts showed significantly (p ≤ 0.05) better color stability than those without antioxidants. These results indicate that edible plant extracts are promising sources of natural antioxidants and can potentially be used as functional preservatives in meat products.     

Enhancing the thermal destruction of Escherichia coli O157:H7 in ground beef patties by trans-cinnamaldehyde

The effect of trans-cinnamaldehyde (TC) on the inactivation of Escherichia coli O157:H7 in undercooked ground beef patties was investigated. A five-strain mixture of E. coli O157:H7 was inoculated into ground beef (7.0 log CFU/g), followed by addition of TC (0, 0.15, and 0.3%). The meat was formed into patties and stored at 4 °C for 5 days or at −18 °C for 7 days. The patties were cooked to an internal temperature of 60 or 65 °C, and E. coli O157:H7 was enumerated. The numbers of E. coli O157:H7 did not decline during storage of patties. However, cooking of patties containing TC significantly reduced (P < 0.05) E. coli O157:H7 counts, by >5.0 log CFU/g, relative to the reduction in controls cooked to the same temperatures. The D-values at 60 and 65 °C of E. coli O157:H7 in TC-treated patties (1.85 and 0.08 min, respectively) were significantly lower (P < 0.05) than the corresponding D-values for the organism in control patties (2.70 and 0.29 min, respectively). TC-treated patties were more color stable and showed significantly lower lipid oxidation (P < 0.05) than control samples. TC enhanced the heat sensitivity of E. coli O157:H7 and could potentially be used as an antimicrobial for ensuring pathogen inactivation in undercooked patties. However detailed sensory studies will be necessary to determine the acceptability to consumers of TC in ground beef patties.     

Comparative efficacy of pomegranate juice, pomegranate rind powder extract and BHT as antioxidants in cooked chicken patties

A study was carried out to evaluate the antioxidant potential of pomegranate juice (PJ), rind powder extract (RP) and butylated hydroxyl toluene (BHT) in cooked chicken patties during refrigerated storage. Freshly minced chicken meats were assigned to one of the following four treatments: control (meat treated with no antioxidants); 10 mg equivalent PJ phenolics per 100 g meat; 10 mg equivalent RP phenolics per 100 g meat; 10 mg BHT per 100 g meat. The patties formed from the minced meats were grilled for 20 min and stored under aerobically at 4 °C for 15 days. Total phenolic content (as tannic acid equivalent) significantly (P < 0.05) increased from 152 in control to 195 and 224 μg/g in PJ and RP patties. Addition of PJ or RP did not affect any of the sensory attributes. The TBARS values were significantly (P < 0.05) reduced from 1.272 in control patties to 0.896, 0.763 and 0.203 mg malonaldehyde per kg samples in BHT, PJ and RP patties, respectively. The RP treatment substantially inhibited (P < 0.01) lipid oxidation in cooked chicken patties to a much greater extent than BHT treatment. The PJ or RP at a level of 10 mg equivalent phenolics/100 g meat would be sufficient to protect chicken patties against oxidative rancidity for periods longer than the most commonly used synthetic antioxidant like BHT.     

Culinary herbs inhibit lipid oxidation in raw and cooked minced meat patties during storage

The effect of dried spices and the ethanol extract of those spices was studied on the stability of fresh chicken minced meat, and fresh and cooked pork patties pretreated with NaCl during refrigerated and frozen storage. The antioxidant activities of the spices were measured by thiobarbituric acid reactive substances (TBARS) and peroxide value (POV) in meat samples. The lipid oxidation was effectively inhibited in the chicken meat treated with several dry spices diminishing the TBARS to a range of 32% and 83% of those found in the control samples in frozen stored meat for 6 months. Marjoram, wild marjoram and caraway were the most effective dry spices. Ethanolic extracts of the same spices were more potent as antioxidants by lowering the concentration of the TBARS to a range of 20–27% of those found in the control samples. Addition of sodium salt to the minced pork resulted very high concentrations of the oxidation products originated from the polyunsaturated fatty acids. The treatment with ethanolic extract of spices (sage, basil, thyme and ginger) significantly inhibited the lipid peroxidation in refrigerated and chilled pork patties pretreated with NaCl by reducing both POV and TBARS. Heat treatment with microwaves produced significantly elevated levels of both lipid peroxides and TBARS, but the amount of these oxidation products was less than 10% in spice‐treated salted meat samples compared to that in untreated ones. Lipid peroxidation also grew continuously during the storage period at −18°C in raw and cooked samples. Ethanolic extracts of spices had a very strong antioxidative effect inhibiting lipid peroxidation in heat‐treated meat products during frozen storage. The highest antioxidant activity was observed in the case of ginger. High correlation coefficients were found between TBARS and POV both in raw and cooked pork patties (0.86, 0.91, respectively) during frozen storage. It is supposed that these compounds originated from the polyunsaturated fatty acids during oxidation processes but at different stages. Utilization of spices, spice mixtures or spice extracts in semi‐prepared meat products intended to be frozen for up to 6 months or more before consumption is proved to be advantageous in regard of shelf life of the food, as well as of human health, because of the beneficial effect of spices in inhibition of lipid peroxidation during heat treatment and chilling storage. © 1999 Society of Chemical Industry     

Antioxidant activity of Carob fruit extracts in cooked pork meat systems during chilled and frozen storage

The purpose of this study was to evaluate the effect of adding condensed tannins in the form of non-purified (Liposterine^®) or purified (Exxenterol^®) extracts obtained from Carob fruit to prevent lipid cooked pork meat systems from oxidising during chilling and frozen storage. The antioxidant activity of these extracts was compared with that of α-tocopherol. Meat lipid alteration was evaluated as thiobarbituric acid reactive substances content (TBARS) and polar material-related triglyceride compounds followed by high-performance size-exclusion chromatography (HPSEC). TBARS levels were lower (P < 0.05) in samples containing Liposterine (LM), Exxenterol (EM), and α-tocopherol (TM) than in control sample (CM) under chilled storage. TBARS formation was similar (P > 0.05) for LM and EM but lower (P < 0.05) than for TM. Polar material increased several times in all samples, but significantly less in TM and EM than in LM. Thermal oxidation compounds determined by HPSEC were lower (P < 0.05) in EM than in LM or TM. The changes in polar material were proportionally smaller after six months frozen storage than after chilled storage, with Exxenterol displaying the highest antioxidant protection. Therefore Carob fruit extracts can be successfully used to reduce fat alteration in cooked pork meat at chilled and frozen temperatures.     

Effects of gamma irradiation and electron beam irradiation on quality,sensory, and bacterial populations in beef sausage patties

This study compared effects of gamma ray (GR) and electron beam (EB) irradiation on quality (TBARS value, hardness, color), sensory characteristics, and total bacterial populations in beef sausage patties during accelerated storage at 30 °C for 10 days. Beef sausage patties were vacuum-packaged and irradiated by GR and EB at 0, 5, 10, 15, and 20 kGy at room temperature. The results of quality evaluation showed that the effects of GR irradiation were similar (p ? 0.05) to EB irradiation on lipid oxidation, hardness, color and sensory scores of the beef sausage patties. However, GR-irradiated samples had lower (p < 0.05) total bacterial counts than EB-irradiated samples after irradiation, and during storage regardless of irradiation dose. The results indicate that use of GR irradiation up to 10 kGy on patties should be useful in reducing bacterial populations with no adverse effect on quality and most of sensory characteristics (color, chewiness, and taste).     

Suitability of the TBA method for assessing lipid oxidation in a meat system with added phenolic-rich materials

Numerous protocols and modifications of the thiobarbituric acid (TBA) test are available in the literature. The present paper compares the effectiveness of different TBA tests in minimizing the interferences caused by the addition of phenolic-rich materials (wild fruits) as antioxidants in cooked burger patties. The aqueous acid extraction procedure (EM) and a modified distilation TBA method (DM) were tested with different conditions of incubation – boiling (B) vs. room temperature (RT) – for monitoring lipid oxidation in cooked burger patties during refrigerated storage. DM-B and DM-RT were more suitable than EM procedures for assessing TBA-reactive substances (TBA-RS) in meat samples containing compounds such as anthocyanins, with similar spectral properties than that of the TBA–malondialdehyde (MDA) adduct. Additionally, interferences caused by browning development during incubation were avoided by DM procedures or by performing RT incubations. Correlations between TBA-RS numbers and hexanal contents in cooked pork burger patties were calculated in order to corroborate the suitability of the tested TBA procedures. The DM-RT procedure showed the highest correlation with hexanal content (R² = 0.90; p < 0.001).     

Inhibitory effect of marinades with hibiscus extract on formation of heterocyclic aromatic amines and sensory quality of fried beef patties

Heterocyclic aromatic amines (HAA) are carcinogenic compounds found in the crust of fried meat. The objective was to examine the possibility of inhibiting HAA formation in fried beef patties by using marinades with different concentrations of hibiscus extract (Hibiscus sabdariffa) (0.2, 0.4, 0.6, 0.8 g/100 g). After frying, patties were analyzed for 15 different HAA by HPLC-analysis. Four HAA MeIQx (0.3–0.6 ng/g), PhIP (0.02–0.06 ng/g), co-mutagenic norharmane (0.4–0.7 ng/g), and harmane (0.8–1.1 ng/g) were found at low levels. The concentration of MeIQx was reduced by about 50% and 40% by applying marinades containing the highest amount of extract compared to sunflower oil and control marinade, respectively. The antioxidant capacity (TEAC-Assay/Folin–Ciocalteu-Assay) was determined as 0.9, 1.7, 2.6 and 3.5 μmol Trolox antioxidant equivalents and total phenolic compounds were 49, 97, 146 and 195 μg/g marinade. In sensory ranking tests, marinated and fried patties were not significantly different (p > 0.05) to control samples.     

Roselle (Hibiscus sabdariffa L.) and soybean oil effects on quality characteristics of pork patties studied by response surface methodology

Response surface methodology was used to investigate the effect and interactions of processing variables such as roselle extract (0.1–1.3%), soybean oil (5–20%) on physicochemical, textural and sensory properties of cooked pork patties. It was found that reduction in thickness, pH, L* and b* values decreased; however, water-holding capacity, reduction in diameter and a* values increased, respectively, as the amount of roselle increased. Soybean oil addition increased water-holding capacity, reduction in thickness, b* values of the patties. The hardness depended on the roselle and soybean oil added, as its linear effect was negative at p < 0.01. The preference of color, tenderness, juiciness, and overall quality depend on the addition of roselle and soybean oil. The maximum overall quality score (5.42) was observed when 12.5 g of soybean oil and 0.7 g of roselle extract was added. The results of this optimization study would be useful for meat industry that tends to increase the product yield for patties using the optimum levels of ingredients by RSM.     

Effect of plant phenolics,tocopherol and ascorbic acid on oxidative stability of pork patties

BACKGROUND: There is great interest in the use of naturally occurring antioxidants to delay oxidation in meat products. The effect of rosemary extract (RE), green tea extract (TE), tocopherol, trolox, ascorbic acid (AA) and ascorbyl palmitate (AP), at levels of 50–200 ppm of antioxidant components, on colour (CIE L*a*b*), lipid (TBARS) and protein oxidation (thiol groups) in fresh, frozen and cooked pork patties during illuminated chill storage was investigated. Individual components of RE and TE were also tested. RESULTS: RE, TE, AP, tocopherol and trolox equally inhibited lipid oxidation in fresh and frozen patties, whereas for cooked patties RE was most effective. AA stimulated lipid oxidation. No dose effect in the range of 50–200 ppm was found for fresh and frozen patties, whereas for cooked patties higher doses of RE and TE more efficiently prevented lipid oxidation. Protein oxidation was hardly influenced by antioxidant treatment. Colour stability decreased as follows: tocopherol, AA and AP > RE and TE > trolox. Antioxidant properties of the extracts and their major antioxidant components were comparable. CONCLUSION: The relative effect of the antioxidants depends on the oxidation parameter assessed, the applied dose and the hydrophilic/lipophilic character. Copyright © 2009 Society of Chemical Industry     

Effect of freeze-thaw cycles on physicochemical properties and color stability of beef semimembranosus muscle

The effects of freeze-thaw cycle on the physicochemical properties and color stability of beef semimembranosus muscle during cold storage were investigated. Meat was tested for effects on color (CIE L^?, a^?, b^?), myoglobin content (%), metmyoglobin reducing ability (MRA), thiobarbituric acid reactive substances (TBARS), heme pigment content (ppm), SDS-PAGE profile, and tissue microstructure. Fresh meat showed significantly (p < 0.05) higher values of CIE a^?, CIE b^?, and oxymyoglobin content (%) compared to freeze-thawed meat during cold storage. However, metmyoglobin content (%) was higher in freeze-thawed meat than in fresh meat during 7 days of cold storage. There were no significant differences (p > 0.05) in MRA among the treatments during cold storage. The TBARS value (0.387 mg/kg) of fresh meat was significantly (p < 0.05) higher than those of freeze-thawed meats after 5 days of cold storage. These results suggest that the freeze-thaw process could accelerate the deterioration of meat color.