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1.
用~(31)P NMR研究猪背最长肌中3种多聚磷酸钠的水解   总被引:2,自引:0,他引:2  
试验利用31P核磁共振(NMR)技术研究了焦磷酸四钠(TSPP)、三聚磷酸钠(STPP)和六偏磷酸钠(HMP)在猪背最长肌中的水解变化。研究结果表明,TSPP和STPP的最终水解产物为正磷酸盐(Pi),TSPP在猪肉背最长肌中12h后还未完全水解,STPP在12h时已经完全水解为焦磷酸盐和正磷酸盐,派生的焦磷酸盐继续水解;HMP在肉中是稳定的,只有少量支链多聚磷酸盐能逐渐分解为Pi。  相似文献   

2.
The dynamic hydrolysis of tetrasodium pyrophosphate (TSPP), sodium tripolyphosphate (STPP) and polyphosphate compound, which was catalyzed by purified pyrophosphatase (PPase) and myosin‐ tripolyphosphatase (TPPase) from the silver carp dorsal muscle, was studied using 31P NMR spectroscopy. In the PPase + TSPP system, the pyrophosphate (PP) was hydrolyzed quickly and completely within 8 h and the hydrolysis rate of PP was 12.51%/h. In the TPPase + STPP system, the first‐order hydrolysis of tripolyphosphate (TPP) was not yet complete after 48 h, and the derived PP accumulated progressively. Given the coexistence of PPase and TPPase, only 1.20% of TPP in STPP alone remained after 48 h. However, the generation rate of Pi in the polyphosphate compound (TSPP: STPP: sodium hexametaphosphate = 1: 8: 1) was 0.76%/h, which was less than 0.88%/h in STPP alone. In the presence of polyphosphatases, the decrease of PP or TPP content in the polyphosphate compound was not as rapid as that in TSPP or STPP alone due to the inhibitory effect of PP on TPPase and the effect of low system pH on PPase. The understanding of polyphosphates hydrolysis mechanism was capable of developing the advanced polyphosphate mixture in order to reduce the phosphate residue in fish products.  相似文献   

3.
Chicken breast muscle was marinated and tumbled in solutions of 7% NaCl and 1.2% of disodium pyrophosphate (DSPP), tetrasodium pyrophosphate (TSPP), tetrapotassium pyrophosphate (TKPP), sodium tripolyphosphate (STPP), or glass phosphate. Dynamic mechanical thermal analysis was used to measure storage modulus and Tan δ as samples were heated from 25 to 75C. For untreated samples, four thermal transitions were noted with the most significant transition at 55.8C. Addition of NaCl and phosphate reduced the number of distinct events, and decreased the major transition to temperatures around 46–48C. Uncooked, marinated samples had lower G' and Tan δ. Treated samples also showed an increase in G' over the 25–45C range. Heating caused the greatest changes in treated samples, with values of G'75C and Tan δ75C similar to untreated samples. Different phosphate types resulted in significant differences in G' and Tan δ values. G' values correlated well with Young's modulus, but not with Warner-Bratzler shear values or expressible moisture. Results are discussed in terms of changes in muscle proteins resulting from exposure to NaCl and phosphates, as well as to heat.  相似文献   

4.
Survival and growth of inoculated Clostridium sporogenes PA 3679 and of natural aerobic and anaerobic bacterial flora were studied in cooked, vacuum packed bratwurst containing 0.5% phosphates during refrigerated (5°C) and subsequent temperature abuse storage (24°C). Sodium acid pyrophosphate (SAPP), sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP) and sodium polyphosphate glassy (SPG) were tested. No significant bacterial inhibition by any phosphate was observed during refrigerated storage, nor was there appreciable growth in the control bratwurst. However, SAPP significantly inhibited aerobic and anaerobic bacteria (including C. sporogenes) upon temperature abuse, followed in effect by TSPP and STPP. Cooking to 65.5°C helped retain antimicrobial properties of phosphates to some extent. Enzymatic hydrolysis of phosphates is postulated as a major factor in loss of antimicrobial properties of phosphates in processed meats.  相似文献   

5.
四种多聚磷酸钠在鸡胸肉中水解的^31P核磁共振研究   总被引:3,自引:0,他引:3  
本文利用^31P核磁共振技术(NMR)研究厂添加到鸡胸肉(CB)中的焦磷酸四钠(TSPP)、焦磷酸二氢二钠(DSPP)、三聚磷酸钠(STPP)和六偏磷酸纳(HMP)所发生的水解。研究结果表明,TSPP、DSPP、STPP和HMP在鸡胸肉中均发生水解。TSPP在10h内完全水解为正磷酸盐。DSPP水解较慢,10h后仍占核磁共振总可测磷的40%。STPP在10h时已经完全水解为焦磷酸盐和正磷酸盐,10h之后由三聚磷酸钠产生的焦磷酸盐继续水解。在HMP腌制液处理的鸡胸肉匀浆物中,没有焦磷酸盐存在,两端的磷原子到10h时的相对含量为零,内部磷原子的相对含量在10h内基本保持不变。  相似文献   

6.
Chemical and functional properties of various blends of phosphate were examined and compared with the conventional phosphate (M-CP: a mechanical blend [50:50] of sodium tripolyphosphate [STPP] and tetrasodium pyrophosphate [TSPP]). Regardless of solution temperature and brine concentration, the solubilities of various blends of phosphates, especially M-1 (a mechanical blend [50:50] of tetrapotassium pyrophosphate and STPP), M-LC (a long-chained sodium hexametapolyphosphate [SHMP] treated with trisodium phosphate [TSP]) and M-MC (a middle-chained SHMP treated with TSP), except for C-S (a chemical blend [50:50] of STPP and TSPP for faster/higher solubility) and C-V (a chemical blend [50:50] of STPP and TSPP for higher viscosity), were higher than that of M-CP. The scanning electronic microscopic image revealed that the structures of various blends of phosphate were quite different. Comparing with M-CP, C-V was superior in viscosity, water retention ability (WRA), emulsifying activity and cooking stability. M-1 was superior in WRA compared to M-CP.

PRACTICAL APPLICATIONS


Conventional blending for phosphates is typically made through simple mechanical mixing. In our study, we featured chemically blended phosphates and found that some of them demonstrated superior functional properties. With this advantage, the use of chemically blended phosphate could reduce the usage level while achieving a similar or better performance.  相似文献   

7.
The effects of 0.5% sodium acid pyrophosphate (SAPP), sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP) and sodium polyphosphate glassy (SPC) on aerobic mesophilic and psychrotrophic bacterial growth and on survival of inoculated Stuphylococcus aureus Z 88 were investigated in uncooked bratwurst stored at 5°C for 7 days. No significant microbial inhibition by phosphates was found, although SAPP addition resulted in consistently lower total aerobic plate counts. Phosphate-induced pH differences in the sausages had no effect on bacterial numbers. The possible role of meat enzymes in the hydrolysis of condensed phosphates to microbiologically inactive species is discussed.  相似文献   

8.
采用免试剂离子色谱法同时检测焦磷酸四钠(tetrasodium pyrophosphate,TSPP)、三聚磷酸钠(sodiumtripolyphosphate,STPP)和混合磷酸盐(m(TSPP)∶m(STPP)∶m(六偏磷酸钠)=3∶4∶3)在猪背最长肌、鱼背侧肌以及鸡胸大肌中的水解情况。结果表明,多聚磷酸盐在肌肉中的水解情况存在着差异。单一的TSPP在鸡胸大肌中的水解速率最快,TSPP在猪背最长肌中水解量比在鱼背侧肌中多。将STPP或混合磷酸盐加入到肌肉中,均在猪背最长肌中的水解速率最快,在鸡胸大肌中次之,在鱼背侧肌中最慢。本研究探索多聚磷酸盐在不同物种肌肉中的动态变化,为调控多聚磷酸盐的水解进程,指导多聚磷酸盐在不同物种肌肉中的合理添加提供了理论依据。  相似文献   

9.
Chemical, physical, and sensory effects of 0.4% sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP) and three commercial phosphate blends were studied in frozen beef patties over a 90-day storage period at ?20°C. Addition of phosphates significantly (P<0.05) increased pH, soluble orthophosphates, Hunter color a values, cook yields and overall acceptability scores. Phosphate addition did not affect (p>0.05) proximate analysis, texture, and flavor scores. Hunter L (lightness) and b (yellowness) values were also unaffected by phosphates. Overall quality of patties, as measured by thiobarbituric acid (TBA) numbers and cooking yields, was improved by all phosphates. There were indications that phosphates interfered with the distillation TBA test.  相似文献   

10.
Calcium chloride (CaCl2) and phosphates are important additives to improve product quality during meat processing. Response surface methodology was used to study the influence of CaCl2 and phosphates on the hardness, water‐holding capacity (WHC) and ultra‐structure of salt‐soluble goose meat protein gels. The results show that the hardness and WHC of salt‐soluble protein gels increased significantly when CaCl2 concentration was increased and phosphates were added. Scanning electron microscopy showed that tetrasodium pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) had a greater impact on the cross‐linking and pore diameter of the gel networks than sodium hexametaphosphate (SHMP). At the 0.02 m and 4:3:2 of CaCl2 concentration and the ratio of TSPP, SHMP and STPP, hardness and WHC values were 114.55 gf and 96.65%, which corresponded to the prediction value of our model. Further results showed that the hardness and WHC of gels reached the maximum with 0.3% of phosphates levels.  相似文献   

11.
Microbiological effects of 0.4% sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP), and three commercial phosphate blends were studied in frozen (90 days, ?20°C) and subsequently temperature-abused (24–25°C, 24 hr) beef patties. Phosphates did not significantly (p>0.05) reduce mesophilic, psychrotrophic, presumptive 5. aureus and lactic acid bacterial numbers during frozen storage of the patties, but one of the commercial blends and TSPP inhibited bacterial growth upon subsequent elevated-temperature abuse. However, bacterial inhibition by phosphates during temperature abuse was not sufficient to prevent spoilage of the patties.  相似文献   

12.
ABSTRACT: This study investigated the effects of 10% (w/v) salt, trisodium phosphate (TSP), sodium tripolyphosphate (STPP), and tetrapotassium pyrophosphate (TKPP) washes on removal of attached Salmonella typhimurium from sterile chicken breast patties, as well as on their injury and survival in a refrigerator for 16 d, in a –20 °C freezer for 10 mo, and after 3 freeze-thaw cycles. S. typhimurium were grown on chicken patties at 20 °C for 20 h, washed, and enumerated by plating on selective and nonselective media. Salt and phosphates washing significantly lowered the survival populations of attached S. typhimurium on patties, but did not cause any significant sublethal injury of attached S. typhimurium , irrespective of storage treatments. The TSP washes showed superior effects of removing and inactivating S. typhimurium compared to other washing treatments.  相似文献   

13.
The effect of concentration and type of phosphate on quality of pre‐rigor poultry breast was evaluated. Non‐aged breasts (NAC) and aged whole birds (AC) were non‐injected controls. Injection marination increased the final product yield and moisture content of breasts compared with AC and NAC. Tetrasodium pyrophosphate (TSPP)‐injected breast had the highest final product yield. TSPP and sodium tripolyphosphate (STPP) injection had similar effects on purge, net weight increase, moisture and expressible moisture. TSPP could only be used in low‐salt marinades. Hexametaphosphate (GLASS)‐injected breast had the highest pick‐up but the lowest retention and moisture content. The shear force of phosphate‐injected breasts was lower than that of NAC and similar to or lower than that of AC breasts. © 2000 Society of Chemical Industry  相似文献   

14.
Beef biceps femoris muscles (n=45) were used to evaluate the effect of enhancement with solutions containing sodium hexametaphosphate (SHMP), sodium tripolyphosphate (STPP), or tetrasodium pyrophosphate (TSPP) at either 0.2% or 0.4% of product weight, without sodium chloride. All solutions were injected into muscle samples at either 112% (12% pump) or 118% (18% pump) of raw product weight. Muscles enhanced with STPP or TSPP had a higher (P<0.05) pH than SHMP or untreated muscles (CNT), whereas there was no difference (P>0.05) in pH between SHMP and CNT. Muscles enhanced with STPP had less (P<0.05) free water than CNT, whereas SHMP and TSPP did not differ from CNT. However, direct comparison of phosphate types revealed no difference (P>0.05) in free water. Steaks enhanced with SHMP had greater (P<0.05) cooking losses than CNT, whereas steaks treated with STPP or TSPP did not differ (P>0.05) from CNT. Phosphate inclusion at 0.2% allowed for greater (P<0.05) cooking losses than CNT, whereas 0.4% phosphate inclusion exhibited similar (P>0.05) cooking losses as CNT. Although there were no differences (P>0.05) in cooking loss between pump rates, steaks enhanced at an 18% pump rate had greater (P<0.05) cooking losses than CNT, whereas those enhanced at 12% had similar (P>0.05) cooking losses as CNT. Enhancement with any of the three phosphate types or either concentration did not improve (P>0.05) sensory tenderness or juiciness characteristics compared to CNT, but enhancement at an 18% pump rate allowed for improved (P<0.05) overall tenderness, compared to a 12% pump rate. These results suggest that while phosphate enhancement independent of sodium chloride generally did not improve water retention, cooked yields and palatability compared to untreated samples, utilizing higher phosphate concentrations or utilizing STPP or TSPP effectively retained the additional water associated with solution enhancement, allowing for similar free water and cook yields as untreated samples.  相似文献   

15.
The hydrolysis of tripolyphosphate and pyrophosphate in comminuted chicken muscle was examined quantitatively by 31P n.m.r. Ageing the muscle before addition of phosphates resulted in a similar change of the hydrolysis rate of both species. By contrast addition of sodium chloride caused very rapid hydrolysis of tripolyphosphate and slowing of the hydrolysis of pyrophosphate. Untreated muscle showed very low levels of phosphocreatine immediately after death and complete loss of ATP within one hour.  相似文献   

16.
Improving food quality among consumers is of high importance. This case in fish meat due to its quick spoilage is the more obvious. Therefore in this study in order to maintain and improve the quality of fish meat, effect of pretreatment with three different phosphate compounds including sodium tripolyphosphate (STPP), sodium pyrophosphate (PP) and mixture of them (STPP + PP) in combination with vacuum packaging (VP) on Rutilus frisii kutum fillets stored in ice was investigated. Phosphate pretreatment showed the synergistic effect with VP on reduction of psycrophilic bacteria, chemical and sensory deterioration of Rutilus frisii kutum fillets as evidenced by the lowered microbial counts, thiobarbituoric acid and total volatile base, compared with samples stored in air and those kept under VP. Pretreatment with PP resulted in the retarded protein denaturation as evidenced by the reduced changes in sulfhydryl content during the extended storage. Increase in water holding capacity accompanied by the decrease in pH was observed in samples pretreated with phosphates, especially tripolyphosphate. No marked autolytic degradation in samples kept under VP with and without phosphate pretreatment was observed throughout the storage as indicated by no changes in electrophoresis patterns. Determined shelf life based on psychrophilic bacteria counts for Rutilus frisii kutum fillets pretreated with STPP and stored under VP, until 15 days and according to sensory analysis until 12 days compared with samples stored in air. Therefore, the effective retardation of psycrophilic bacteria, chemical and sensory deterioration of Rutilus frisii kutum fillets stored under VP could be achieved by pretreatment with tripolyphosphate.  相似文献   

17.
The effects of preblending, order of addition and the physical state of alkaline phosphates on the stability of reduced sodium chloride (0.75%) meat emulsions were determined. Preblending meat batches with reduced sodium chloride for 16 hr resulted in no significant effect upon the stability of meat emulsions, with or without the presence of alkaline phosphates. However, the addition of sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP) significantly improved emulsion stability. Neither the order of TSPP addition in relation to that of sodium chloride nor the physical state of its addition (dry or in solution) affected emulsion stability or the soluble protein level.  相似文献   

18.
Enhancement of beef biceps femoris muscles (n=45) with solutions comprising sodium hexametaphosphate (SHMP), sodium tripolyphosphate (STPP), or tetrasodium pyrophosphate (TSPP) at either 0.2% or 0.4% of product weight, with the exclusion of sodium chloride, was performed to observe the independent phosphate effects on instrumental color during simulated retail display. All solutions were injected into muscle samples at either 112% (12% pump) or 118% (18% pump) of raw product weight. All three phosphate types maintained higher (P<0.05) L* values than untreated steaks (CNT) through 5 days-of-display, and SHMP had higher (P<0.05) L* values than STPP and TSPP through 7 days-of-display. Additionally, steaks with 0.2% phosphate inclusion were lighter (L*; P<0.05) than CNT throughout display, and were lighter (P<0.05) than steaks enhanced with 0.4% phosphates through 7 days of display. Steaks enhanced with TSPP had higher (P<0.05) a* values than CNT on days 5 and 7 of display, whereas SHMP- or STPP-enhanced steaks generally had similar (P>0.05) a* values as CNT after 3d of display. Direct comparison of phosphate concentrations revealed no differences (P>0.05) in a* values. Only steaks enhanced with TSPP were more vivid (P<0.05) and had higher (P<0.05) proportions of oxymyoglobin than CNT on days 5 and 7 of display. However, direct comparison of phosphate types indicated that TSPP- and STPP-enhanced steaks had similar (P>0.05) oxymyoglobin proportions during display. Phosphate inclusion at 0.4% maintained higher (P<0.05) oxymyoglobin proportions than 0.2% phosphate inclusion through 5 days-of-display. These results indicate that while 0.2% phosphate concentrations maintain lighter color, 0.4% concentrations can more effectively retain oxymyoglobin during display. Additionally, only steaks enhanced with TSPP were redder, more vivid, and had higher oxymyoglobin proportions than untreated steaks during the latter stages of display.  相似文献   

19.
肉中添加多聚磷酸盐的研究进展   总被引:7,自引:3,他引:4  
多聚磷酸盐是世界各国广泛应用的食品添加剂,是肉制品加工中不可缺少的添加物,如焦磷酸盐、聚磷酸盐和偏磷酸盐等。磷酸盐的在改善肉品的品质中的作用很多。利用先进的31PNMR技术可以对添加到肉中的多聚磷酸盐水解过程进行动态监测,为弄清多聚磷酸盐在肉中的作用原理提供依据。另外本文还介绍了多聚磷酸盐与肌肉蛋白质的相互作用。  相似文献   

20.
Calcium is a mineral naturally present in water and may be included into meat products during processing thereby influencing meat quality. Phosphates improve myofibril swelling and meat water-holding capacity (WHC) but can be sensitive to calcium precipitation. In this study, pork shoulder meat was used to investigate the impact of calcium at 0, 250, and 500 ppm and phosphate type [sodium pyrophosphate (PP), tripolyphosphate (TPP), and hexametaphopshate (HMP)] at 10 mM on nitrite-cured protein extract color at various pH levels (5.5, 6.0, and 6.5) and crude myofibril WHC at pH 6.0. Neither calcium nor phosphates present in the curing brines significantly affected the cured color. Increasing the pH tended to promote the formation of metmyoglobin instead of nitrosylmyoglobin. The ability of PP to enhance myofibril WHC was hampered (P < 0.05) by increasing the calcium concentration due to PP precipitation. Calcium also decreased the solubility of TPP but did not influence its enhancement of WHC. On the other hand, HMP was more tolerant of calcium but the soluble Ca-HMP complex was less effective than free HMP to promote water binding by myofibrils. The depressed muscle fiber swelling responding to added calcium as evidenced by phase contrast microscopy substantiated, to a certain extent, the deleterious effect of calcium, suggesting that hardness of curing water can significantly affect the quality of cured meat products. PRACTICAL APPLICATION: Although not affecting nitrite-cured color, calcium hampers the efficacy of phosphates to promote water binding by muscle proteins, underscoring the importance of water quality for brine-enhanced meat products.  相似文献   

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