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The Effect of Different Physical and Chemical Factors on Pork Myoglobin Stability

Author: XiangDan
Tutor: LiHongJun
School: Southwestern University
Course: Agricultural Products Processing and Storage
Keywords: Rongchang Pig Myoglobin NaCl High pressure Temperature
CLC: S828
Type: Master's thesis
Year: 2010
Downloads: 188
Quote: 3
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Abstract

At home and abroad to study various physical and chemical factors on meat color-depth understanding of the the Rongchang pig pork physiological characteristics, the test subject is based on the the Rongchang pig pork raw materials selected temperature, salt concentration, sodium nitrite, handle meat like pressure and other physical and chemical factors, sensory score, colorimeter, hair color rate and Determination of myoglobin, and changes the color indicators significant, this experiment Rongchang pig objective evaluation of color research Rongchang pig pork myoglobin pork color stability under a variety of physical and chemical factors, is to promote the consumption of Rongchang pig after doing data base. The main findings are as follows: 1 sodium nitrite increases with the increase in the amount of sodium nitrite added muscle color on the Rongchang pork products color stability the impact study marinated processing process sensory score. Determination of Meat chroma value test. The longissimus muscle L * values ??and the L * value of the hind leg muscles trend. Added nitrite in three groups of L * value changes, rather than add the nitrite pork L * value changed little. 0-48h within the pickling time was not added nitrite pork a * values ??increase, and the nitrite is added, a * values ??decreased significantly. 0-48h within the pickling time, all test groups b * values ??were tested growth trends, but the effect is not obvious. Wherein the higher the content of nitrite, and b * values ??of the slower increase. Determination of meat marinated rate of hair color change can be seen within 0-150mg/kg the add greater the amount of the more obvious effects of hair color; is preserved early (0-8h), hair color increased significantly (Add 50, 100, and 150 mg / kg, respectively, from 12% to 41%, from 14% to 47% and from 18% to 58%). From the sodium nitrite to generate the nitroso hemoglobin, in the curing of the initial (0-8h), the maximum generation amount (data not listed). Not added nitrite in the curing process, in addition to the total amount of myoglobin and myoglobin proportion have undergone a significant change. Add nitrite pork, marinated the longer deoxy myoglobin (DeoxyMb) and high-speed rail myoglobin (MetMb) lower proportion of three kinds of myoglobin, oxymyoglobin (MbO2) ratio slightly , but the increase was not significant. 2 NaCl concentration of myoglobin concentration of NaCl treatment after the meat extract (pH 6.8 sodium phosphate buffer) absorption spectra and the total amount of myoglobin change the color stability of of Rongchang pork products. With the increase in the concentration of NaCl, 3% NaCl solution in the corresponding absorption spectrum curve line absorbance values ??significantly highest; NaCl concentration of 2% and 4% of the corresponding absorption spectrum curve similar approach; NaCl concentration of 5% of the corresponding absorption The spectral curve of the lowest absorbance values. Room temperature, the meat samples after different NaCl concentration (pH 6.8 sodium phosphate buffer) was extracted related changes in the proportion of myoglobin. The proportion of deoxy myoglobin (DeoxyMb), a slight decrease; proportion of high-speed rail myoglobin (MetMb), almost unchanged; the oxymyoglobin (MbO2) the ratio of the major changes: in 3% NaCl solution oxygen the aggregate the myoglobin (MbO2) have the highest proportion, followed by 4% NaCl solution of 5% NaCl solution of oxymyoglobin (MbO2) in the proportion of the lowest. The highest rate of myoglobin save 3% NaCl solution; 4% NaCl solution, followed by; the lowest preservation rate of 5% NaCl solution myoglobin. Preservation rate of 20 ~ 60 ℃, myoglobin. Different concentrations of NaCl solution, with increasing temperature, the preservation rate of myoglobin. Refinement of 2%, the NaCl concentration of between 3% and 4% of the value during the test found that the NaCl concentration is 3%, the meat-like extract absorbance maximum; in NaCI; concentration is 2% , the lowest value of the light absorption of the extract of the meat samples. 3 temperature absorption spectrum changes and the total amount of myoglobin myoglobin the Rongchang pork products color stability impact study different temperature processed meat extract (pH 6.8 sodium phosphate buffer). With increasing temperature, the temperature 20 ° C, 30 ° C and 40 ℃ extract absorbance values ??similar to the waveform of the spectrum did not change significantly when the temperature is 50 ° C and 60 ℃, meat-like heat denaturation of myoglobin , the absorption spectrum of the waveform change significantly, the absorbance value decreased. In the temperature handling test process, as the temperature increases, the amount of deoxy myoglobin (DeoxyMb), almost unchanged; the high iron myoglobin (MetMb) a slight increase in the proportion of three kinds of myoglobin; oxymyoglobin the proportion (MbO2) is significantly reduced. Refine the test temperature between 20 ℃ ~ 40 ℃, select the hind leg muscles as a test material. Extract at a temperature of 20 ℃, meat like absorbance maximum; at a temperature of 40 ℃, meat extract the lowest absorbance values. 20 ℃ -40 ℃ myoglobin characteristic absorption peaks, gradually weakened as the temperature increases, the characteristic absorption peak. UHP treated muscle color sensory score hind leg parts and the back part of the longus muscle sensory score was significantly lower with the increase in the value of high pressure treatment, 4 high-voltage color stability of of Rongchang pork products. Know, after UHP processing, meat color change trend: the red value (a *) becomes smaller, increasing the luminance value (L *), yellowness value (b *) changed little through the entire test. The three forms of myoglobin in EHV effect conversion of oxymyoglobin (bright red) ratio decreases with increasing pressure, the proportion of the rise of high-speed rail myoglobin (amber), deoxy myoglobin protein ratio remained basically unchanged in the entire process of high pressure treatment trial (hindquarters samples about 40% longissimus muscle-like 44%) at the time the color of the meat samples test meat samples after the UHP treatment of 400MPa, L * and a * values ??of the variation difference by the difference 200MPa UHP processing. Meat samples after high pressure treatment value, increased brightness value, reduced red value, yellowness values ??changed little. ,0-12min during the entire experiment curve steep ,12-18min smooth curve. In preserved on the high pressure treatment of meat-like color test, after the same high pressure treatment, the treated samples the color of pink, compared with blank meat samples marinated meat samples a * value decreases the difference smaller, and a * value curve is relatively smooth; marinated meat samples b * value decreases larger difference; marinated meat samples by the L * value increased smaller difference, and the L * value of the curve is relatively smooth.

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