Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators...Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators,free amino acids,and flavor were tested on days 0,10,20,and 30 of curing.The results indicated that curdlan increased product yield by 4.08%,slowed moisture loss during processing,and reduced pH from 6.02 to 5.21.It also decreased the hardness,chewiness,and stickiness in cured pork hind legs,yielding a softer texture.In addition,it slowed the rate of color deterioration and inhibited fat oxidation.Analysis of volatile flavor compounds revealed that curdlan increased the variety of flavor compounds in cured pork hind legs by more than twenty types.The odor activity values of key aroma components(such as linalool and nonanal)also increased to varying degrees,enriching the flavor profile of the cured meat.Thus,curdlan effectively improves the texture,color,and flavor of cured pork hind legs,providing process parameters for industrial production of low-fat cured meat.展开更多
· AIM: To explore the immunomodulatory effects of curdlan on innate immune responses against Aspergillus fumigatus(A. fumigatus) in cultured human corneal epithelial cells(HCECs), and whether C-type lectin recept...· AIM: To explore the immunomodulatory effects of curdlan on innate immune responses against Aspergillus fumigatus(A. fumigatus) in cultured human corneal epithelial cells(HCECs), and whether C-type lectin receptor Dectin-1 mediates the immunomodulatory effects of curdlan.·METHODS: The HCECs were stimulated by curdlan in different concentrations(50, 100, 200, 400 μg/m L) for various time. Then HCECs pretreated with or without laminarin(Dectin-1 blocker, 0.3 mg/m L) and curdlan were stimulated by A. fumigatus hyphae. The m RNA and protein production of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6) were determined by real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The protein level of Dectin-1 was measured by Western blot.· RESULTS: Curdlan stimulated m RNA expression of TNF-α and IL-6 in a dose and time dependent manner in HCECs. Curdlan pretreatment before A. fumigatus hyphae stimulation significantly enhanced the expression of TNF-α and IL-6 at m RNA and protein levels compared with A. fumigatus hyphae stimulation group(P 【0.05).Both curdlan and A. fumigatus hyphae up-regulated Dectin-1 protein expression in HCECs, and Dectin-1expression was elevated to 1.5- to 2-fold by curdlan pretreatment followed hyphae stimulation. The Dectin-1blocker laminarin suppressed the m RNA expression and protein production of TNF-α and IL-6 induced by curdlan and hyphae(P 【0.05).· CONCLUSION: These findings demonstrated that curdlan pretreatment enhanced the inflammatory response induced by A. fumigatus hyphae in HCECs.Dectin-1 is essential for the immunomodulatory effectsof curdlan. Curdlan may have high clinical application values in fungal keratitis treatment.展开更多
为探索可得然胶添加量对大豆分离蛋白(Soy Protein Isolate,SPI)凝胶冻融前后理化性质及结构的影响。文章采用傅里叶变换红外光谱探究大豆分离蛋白的结构变化,并通过分析冻融循环过程中SPI凝胶水分分布状态、持水性、质构特性及微观结构...为探索可得然胶添加量对大豆分离蛋白(Soy Protein Isolate,SPI)凝胶冻融前后理化性质及结构的影响。文章采用傅里叶变换红外光谱探究大豆分离蛋白的结构变化,并通过分析冻融循环过程中SPI凝胶水分分布状态、持水性、质构特性及微观结构,探讨其作用机理。结果表明,随着可得然胶添加量增加,SPI凝胶硬度、持水性和结合水含量呈先增后降趋势。5次冻融循环(5 FTCs)后,SPI凝胶硬度、持水性和水分分布状态均有显著变化。当可得然胶添加量为4 g/100 g时,与未冻融前相较,SPI凝胶硬度增加109.13 g,持水性降低24.05%。添加可得然胶后,SPI凝胶水分子可移动性减弱,维持原本水分分布状态。同时,SPI凝胶网络结构增强,有效延缓冻融循环过程中品质劣变。傅里叶变换红外光谱分析结果表明,添加可得然胶可增强SPI凝胶持水性,促进蛋白质中α-螺旋转化为β-折叠。展开更多
探讨添加可得然胶(0.3%,肉总质量计)以及不同加水量(20%、23%、26%和29%,肉总质量计)对法兰克福香肠品质特性的影响。测定蒸煮损失率、乳化稳定性、色差、质构、流变特性、微观结构以及感官评价,同时应用低场核磁共振(low field nuclear...探讨添加可得然胶(0.3%,肉总质量计)以及不同加水量(20%、23%、26%和29%,肉总质量计)对法兰克福香肠品质特性的影响。测定蒸煮损失率、乳化稳定性、色差、质构、流变特性、微观结构以及感官评价,同时应用低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术测定法兰克福香肠内部水分子的迁移规律。结果表明,在不添加可得然胶对照组中,随着加水量的增加,法兰克福香肠的蒸煮损失率和L*值显著增加(P<0.05),而乳化稳定性、硬度和总体可接受性显著降低(P<0.05)。然而,在添加可得然胶后,在相同加水量条件下显著降低法兰克福香肠的蒸煮损失率,并显著提高肉制品的乳化稳定性、硬度、弹性和总体可接受性(P<0.05)。LF-NMR研究结果表明,可得然胶的添加能够降低法兰克福香肠的弛豫时间,在较高加水量条件下增强对水分子的束缚能力。另外,肉糜的流变学测定结果表明,在相同加水量条件下,添加可得然胶能够提高肉糜在加热终点的储能模量(G’)和损失模量(G"),而且降低相位角正切值(tanδ),说明可得然胶能够在较高加水量条件下提高肉糜的黏弹性。同时,扫描电镜结果表明,较高的加水量会导致蛋白凝胶结构松散,而可得然胶的添加能够显著改善蛋白凝胶的网状结构。上述结果表明,虽然过多的加水量会导致法兰克福香肠的品质下降,但是可得然胶的添加能够在较高加水量条件下显著提高法兰克福香肠的食用品质,为可得然胶在乳化肉糜类肉制品中的应用提供理论依据。展开更多
基金Supported by Sichuan Science and Technology Program(2024ZHCG0091)National Modern Agricultural Industry Technology System Sichuan Swine Innovation Team(SCCXTD-2025-8)+1 种基金Open Fund of Sichuan Provincial Key Laboratory of Meat Processing(24-R-20)China Agricultural Industry Research System(CARS-43).
文摘Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators,free amino acids,and flavor were tested on days 0,10,20,and 30 of curing.The results indicated that curdlan increased product yield by 4.08%,slowed moisture loss during processing,and reduced pH from 6.02 to 5.21.It also decreased the hardness,chewiness,and stickiness in cured pork hind legs,yielding a softer texture.In addition,it slowed the rate of color deterioration and inhibited fat oxidation.Analysis of volatile flavor compounds revealed that curdlan increased the variety of flavor compounds in cured pork hind legs by more than twenty types.The odor activity values of key aroma components(such as linalool and nonanal)also increased to varying degrees,enriching the flavor profile of the cured meat.Thus,curdlan effectively improves the texture,color,and flavor of cured pork hind legs,providing process parameters for industrial production of low-fat cured meat.
基金Supported by National Natural Science Foundation of China(No.81170825No.81470609)+2 种基金Natural Science Foundation of Shandong Province(No.ZR2013HQ007No.ZR2012HZ001)the Specialized Research Fund for the Doctoral Program of Higher Education,2012(No.20123706110003)
文摘· AIM: To explore the immunomodulatory effects of curdlan on innate immune responses against Aspergillus fumigatus(A. fumigatus) in cultured human corneal epithelial cells(HCECs), and whether C-type lectin receptor Dectin-1 mediates the immunomodulatory effects of curdlan.·METHODS: The HCECs were stimulated by curdlan in different concentrations(50, 100, 200, 400 μg/m L) for various time. Then HCECs pretreated with or without laminarin(Dectin-1 blocker, 0.3 mg/m L) and curdlan were stimulated by A. fumigatus hyphae. The m RNA and protein production of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6) were determined by real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The protein level of Dectin-1 was measured by Western blot.· RESULTS: Curdlan stimulated m RNA expression of TNF-α and IL-6 in a dose and time dependent manner in HCECs. Curdlan pretreatment before A. fumigatus hyphae stimulation significantly enhanced the expression of TNF-α and IL-6 at m RNA and protein levels compared with A. fumigatus hyphae stimulation group(P 【0.05).Both curdlan and A. fumigatus hyphae up-regulated Dectin-1 protein expression in HCECs, and Dectin-1expression was elevated to 1.5- to 2-fold by curdlan pretreatment followed hyphae stimulation. The Dectin-1blocker laminarin suppressed the m RNA expression and protein production of TNF-α and IL-6 induced by curdlan and hyphae(P 【0.05).· CONCLUSION: These findings demonstrated that curdlan pretreatment enhanced the inflammatory response induced by A. fumigatus hyphae in HCECs.Dectin-1 is essential for the immunomodulatory effectsof curdlan. Curdlan may have high clinical application values in fungal keratitis treatment.
文摘探讨添加可得然胶(0.3%,肉总质量计)以及不同加水量(20%、23%、26%和29%,肉总质量计)对法兰克福香肠品质特性的影响。测定蒸煮损失率、乳化稳定性、色差、质构、流变特性、微观结构以及感官评价,同时应用低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术测定法兰克福香肠内部水分子的迁移规律。结果表明,在不添加可得然胶对照组中,随着加水量的增加,法兰克福香肠的蒸煮损失率和L*值显著增加(P<0.05),而乳化稳定性、硬度和总体可接受性显著降低(P<0.05)。然而,在添加可得然胶后,在相同加水量条件下显著降低法兰克福香肠的蒸煮损失率,并显著提高肉制品的乳化稳定性、硬度、弹性和总体可接受性(P<0.05)。LF-NMR研究结果表明,可得然胶的添加能够降低法兰克福香肠的弛豫时间,在较高加水量条件下增强对水分子的束缚能力。另外,肉糜的流变学测定结果表明,在相同加水量条件下,添加可得然胶能够提高肉糜在加热终点的储能模量(G’)和损失模量(G"),而且降低相位角正切值(tanδ),说明可得然胶能够在较高加水量条件下提高肉糜的黏弹性。同时,扫描电镜结果表明,较高的加水量会导致蛋白凝胶结构松散,而可得然胶的添加能够显著改善蛋白凝胶的网状结构。上述结果表明,虽然过多的加水量会导致法兰克福香肠的品质下降,但是可得然胶的添加能够在较高加水量条件下显著提高法兰克福香肠的食用品质,为可得然胶在乳化肉糜类肉制品中的应用提供理论依据。
