【作者】 向丹；

【导师】 李洪军；

【作者基本信息】 西南大学 ， 农产品加工及贮藏工程， 2010， 硕士

【摘要】 基于国内国外研究各种理化因素对肉制品颜色的影响,为了能深入认识荣昌猪猪肉各方面的生理性特征,本试验课题是以荣昌猪猪肉为原料,选取温度、盐浓度,亚硝酸钠,高压等理化因素处理肉样,进行感官评分、色差计、发色率和肌红蛋白含量测定,并对各项颜色指标的变化情况进行显著性分析,本实验把荣昌猪的色泽评价客观化,研究荣昌猪猪肉肌红蛋白在各种理化因素下的猪肉颜色稳定性,为以后荣昌猪的推广食用做数据基础。主要研究结果如下：1亚硝酸钠对荣昌猪肉品颜色稳定性影响研究腌制处理过程中肌肉颜色的感官评分随着亚硝酸钠添加量的增加而增大。测定肉品色度值试验。背长肌肌肉的L*值与后腿肌肉的L*值变化趋势一致。添加了亚硝酸盐的三组L*值变化大,而未添加亚硝酸盐的猪肉L*值变化不大。在0-48h腌制时间内,不添加亚硝酸盐的猪肉a*值增加,而添加亚硝酸盐后,a*值明显降低。在0-48h腌制时间内,所有试验组b*值都呈增长趋势,但是效果不明显。其中亚硝酸盐含量越高,b*值变化增加的越慢。测定肉品腌制发色率变化可以看出,在0-150mg/kg的范围内,添加量越大,发色效果越明显；特别是腌制初期(0-8h),发色率明显上升(添加50、100和150 mg/kg分别从12%到41%,14%到47%和18%到58%)。从添加亚硝酸钠生成的亚硝基血色素看,在腌制初期(0-8h),生成量最大(数据未列出)。在腌制过程中,除了未添加亚硝酸盐的一组外,肌红蛋白总量和3种肌红蛋白比例都发生了明显变化。添加亚硝酸盐的猪肉,腌制时间越长,脱氧肌红蛋白(DeoxyMb)和高铁肌红蛋白(MetMb)在3种肌红蛋白的比例越低,氧合肌红蛋白(MbO2)的比例略有增加,但增加不显著。2 NaCl浓度对荣昌猪肉品颜色稳定性影响研究不同NaCl浓度处理后肉样抽提(pH 6.8的磷酸钠缓冲剂)的肌红蛋白吸收光谱和肌红蛋白总量的变化。随着NaCl浓度的增加,3%的NaCl溶液对应的吸收光谱曲线线吸光值明显最高；NaCl浓度为2%和4%的对应的吸收光谱曲线较相似接近；NaCl浓度为5%的对应的吸收光谱曲线吸光值最低。室温下,不同NaCl浓度处理后肉样抽提(pH 6.8的磷酸钠缓冲剂)的相关肌红蛋白比例的变化。脱氧肌红蛋白(DeoxyMb)的比例略有减少；高铁肌红蛋白(MetMb)的比例几乎不变；氧合肌红蛋白(MbO2)的比例发生了较大变化：在3%的NaCl溶液中氧合肌红蛋白(MbO2)所占的比例最高,4%的NaCl溶液中次之,5%的NaCl溶液中氧合肌红蛋白(MbO2)所占的比例最低。3%的NaCl溶液中,肌红蛋白的保存率最高；4%的NaCl溶液次之；5%的NaCl溶液中的肌红蛋白的保存率最低。在20～60℃时,肌红蛋白的保存率相差较大。在不同浓度NaCl的溶液中,随温度的升高,肌红蛋白的保存率都下降。在细化2%、3%和4%之间的NaCl浓度值试验过程中发现,在NaCl浓度值为3%时,肉样抽提液的吸光值最高；在NaCl;浓度值为2%时,肉样抽提液的吸光值最低。3温度对荣昌猪肉品颜色稳定性影响研究不同温度处理后肉样抽提(pH 6.8的磷酸钠缓冲剂)的肌红蛋白吸收光谱和肌红蛋白总量的变化。随着温度的增加,温度20℃、30℃和40℃时,抽提液的吸光率值相近,光谱的波形没有明显改变,当温度是50℃和60℃时,肉样肌红蛋白受热变性,吸收光谱的波形明显改变,吸光值明显下降。在温度处理试验过程中,随着温度升高,脱氧肌红蛋白(DeoxyMb)的量几乎没变；高铁肌红蛋白(MetMb)在3种肌红蛋白的比例略有增加；氧合肌红蛋白(MbO2)的比例显著减少。在细化20℃～40℃之间的温度值的试验过程中,选取后腿肌肉作为试验材料。在温度20℃时,肉样抽提液的吸光值最高；在温度40℃时,肉样抽提液的吸光值最低。在20℃-40℃时肌红蛋白的特征吸收峰明显,随着温度的升高,特征吸收峰逐渐减弱。4高压对荣昌猪肉品颜色稳定性影响研究超高压处理后肌肉颜色的感官评分变化随着超高压处理值的增加,后腿部位和背长肌部位的肌肉的感官评分明显降低。通过整个试验知道,经过超高压处理后,肉品颜色变化趋势：红度值(a*)变小,亮度值(L*)增大,黄度值(b*)变化不大。肌红蛋白的三种存在形式在超高压作用下发生转化,氧合肌红蛋白(鲜红色)的比例随压力的上升而下降,高铁肌红蛋白(黄褐色)的比例在上升,脱氧肌红蛋白的比例在整个超高压处理试验过程中基本保持不变(后腿肉样在40%左右,背长肌肉样44%左右)在处理时间的对肉样颜色的影响的试验中,肉样经过400MPa的超高压处理后,L*和a*值的变化差值比经200MPa超高压处理后的差值大。肉样经过超高压处理值时,亮度值增加,红度值减少,黄度值变化不大。整个试验过程中,0-12min间,变化曲线陡峭,12-18min,曲线变化平稳。在腌制对超高压处理肉样颜色的影响的试验中,经过同样的超高压处理,处理后样品的颜色为粉红色,与空白肉样做对比,腌制肉样a*值减小差值较小,且a*值变化曲线比较平稳；腌制肉样的b*值减小差值较大；腌制肉样L*值增加的差值较小,且L*值变化曲线比较平稳。更多还原

【Abstract】 Based on domestic and international factors in the study of various physical and chemical effects on meat color, in order to deeply understand the physiological characteristics of all aspects of pork Rongchang pig, the experimental subject chose Rongchang pig meat as raw materials, select physical and chemical factors such as the temperature, salt concentration,sodium nitrite, high pressure and so on. the experimental subject get the sensory score, color design, cured color, rate and determination of myoglobin content, and significance analysis, the experimental subject make Rongchang pig color evaluation to be objective, research stability of Rongchang pig meat myoglobin to promote consumption of Rongchang pig meat. The major findings are as follows:1 The research of sodium nitrite on the color stability of pork Rongchang pork products During Curing process, the sensory score of muscle color increases with the addition of the amount of sodium nitrite.Experimental determination of the value of meat color, The change trend of the L* value of Longissimus dorsi muscle and the L* value of hind leg musclesis is in accord. The L* value of the group which didn’t add sodium nitrite changed little; while, the other three groups which added sodium nitrite changed a lot. During 0～48h cured time, the b* value of the groups which didn’t add sodium nitrite increased; while, the a* value of the groups which added sodium nitrite decreased obviously.During 0～48 h cured time, growth trends of the b* values for all test groups increased little, the higher sodium nitrite, the more slowly the b* values increased.From the determination of the change of the rate of the color, we can know, the addition of the sodium nitrite in the 0～150 mg/kg range is larger, the color is more obvious.Espeically in the initial stage (0～8h),the rate of cured color is significantly up (Add 50,100 and 150 mg/kg, respectively from 12% to 41%,14% to 47%and 18% to 58%); nitroso-hemoglobin in in the initial stage (0～8h) generated the largest amount (data not shown).During the curing process, the three groups which added sodium nitrite. With cured time is longer, the ratio of the deoxy myoglobin (DeoxyMb) and metmyoglobin (MetMb) in three kinds of myoglobin is lower; while, the ratio of oxymyoglobin (MbO2) increased slightly.2 The research of NaCl concentration on the color stability of Rongchang pork productsThe sample extraction after different NaCl concentrations (pH 6.8 in sodium phosphate buffer), With the increase of NaCl concentration, the absorption spectrum curve of 3% NaCl solution is the maximum; the absorption curve of NaCl concentration of 2% and 4% NaCl solution is similar; the absorption spectrum curve of NaCl concentration of 5% NaCl solution is the minimum.In room temperature, NaCl concentrations of different samples of meat after the extraction (pH 6.8 in sodium phosphate buffer). The ratio of Deoxy myoglobin (DeoxyMb) decreased slightly; metmyoglobin (MetMb) almost didn’t changed; the proportion of oxymyoglobin (MbO2) significantly changed:the proportion of oxymyoglobin (MbO2) of 3% NaCl solution is the highest proportion;the proportion of oxymyoglobin (MbO2)of 4% NaCl solution followed, the proportion of oxymyoglobin (MbO2) of 5% NaCl solution is the lowest proportion.The preservation rate of myoglobin is the highest in 3% NaCl solution; 4% NaCl solution just followed by; the preservation rate of myoglobin is the lowest in 5% NaCl solution. In the 20～60℃, the preservation rate of myoglobin were quite different. at different NaCl solution concentrations, myoglobin preservation rates all decreased with the increase of temperature.This subject selected the hind leg muscle as the thinning trial test material of 2%.3% and 4% NaCl concentration. When the NaCl concentration is 3%, the absorbance value of the extraction solution is the highest; when the NaCl concentration is 2%, the absorbance of the meat sample is the lowest.3 The research of temperature on the color stability of Rongchang pork productsThe extraction of the meat sample after different temperatures (pH 6.8 sodium phosphate buffer). As the temperature increases, when the temperature is 20℃,30℃and 40℃. The absorbance values of extraction solution are similar, the wave spectrum did not change significantly; when the temperature is 50℃and 60℃. the meat-like myoglobin was heat denaturation, the wave spectrum changed significantly and the absorbance value decreased obviously.In the temperature treatment experiment, the higher the temperature, the amount of oxygen myoglobin (DeoxyMb) almost didn’t change; the ratio of the metmyoglobin (MetMb) in three kinds of myoglobin increased slightly; the ratio of oxymyoglobin (MbO2) decreased significantly.This subject selected the hind leg muscle as the thinning trial test material of 20℃～40℃.when the temperature is 20℃. the absorbance values of extraction solution is maximum; when the temperature is 40℃, the absorbance of the meat sample is minimum. At 20℃-40℃,the characteristic absorption peak of myoglobin is significant; as the temperature increases, the characteristic absorption peaks gradually weakened.4 The research of high pressure on the color stability of Rongchang pork productsWith the increase of high pressure processing value, the sensory score of the hind leg muscles and longissimus dorsi muscle decreased.Through the entire trial.wo know that after high pressure treatment, the change trend of the color of the meat:red value (a*) becomes smaller, the brightness value (L*) increased, yellow value (b*) changed little.Under high pressure, the ratio of oxymyoglobin (bright red) decreases with pressure increases, the ratio of metmyoglobin (brown) was rising, and the proportion of deoxy myoglobin remained unchanged during the the high pressure treatment test (the hind leg muscles in about 40%,44% of longissimus muscle samples or so). In the research of processing time on the color of the meat samples, the L* and a* value of the meat samples which was after high pressure treatment of 400MPa is obviously different from the L* and a* value of the meat samples which was after high pressure treatment of 200MPa. Meat samples after high pressure treatment, brightness value increased and red value decreased, and yellow value changed little. Throughout the experiment, in 0-12-minute, curve changed steeply; in 12-18 minutes, curve changed smoothly.In the test of the influence of the preserved samples after the high pressure process, after the same high pressure, the color of the treated sample were pink. CoMPared with the control of meat, the a* values of the preserved meat sample decreased smaller, and the a* value curve is relatively stable; the b* values of the preserved meat sample decreased relatively largely; the L* values of the preserved meat sample decreased less, and the L* value curve is relatively stable.更多还原