KCl部分替代NaCl协同强化高温对干腌羊火腿品质的影响

Influence of Partial Replacement of NaCl with KCl and High Temperature Enhancement on the Quality of Dry-Cured Lamb Ham

以内蒙古羊后腿为试验原料,采用KCl部分替代NaCl(75%NaCl+25%KCl)和100%NaCl分别对羊腿进行干腌后,结合低温风干、中温发酵以及强化高温成熟工艺(温度由36℃逐渐升至40℃,速率为2℃/d,相对湿度为90%±5%,成熟30 d)制备干腌羊火腿。通过测定加工过程羊火腿的水分含量、水分活度、盐分含量、亚硝酸盐含量以及颜色变化,研究盐替代协同强化高温工艺对干腌羊火腿理化性质的影响;再利用气相色谱-质谱联用(GC-MS)技术分析加工过程干腌羊火腿挥发性风味物质的变化规律。结果表明:盐替代组与食盐组羊火腿加工过程中各理化指标变化趋势相似,其中KCl盐替代可显著降低最终产品总盐分和亚硝酸盐含量(P<0.05)。两组火腿亮度(L^(*)值)整体呈下降的趋势,a^(*)值先下降后上升,b^(*)值总体呈上升趋势,说明KCl部分盐替代在不影响干腌羊火腿色泽的情况下使钠含量降低了25%,且具有较好的感官可接受性;GC-MS结果表明,25%KCl盐替代协同强化高温能促进来自碳水化合物和氨基酸代谢、β-脂质氧化及酯化反应等挥发性化合物的形成,显著增加了产品中3-甲基丁酸、3-甲基丁醛、烷烃、烯烃及酯类物质的含量,同时降低了硫化物相对含量。总体而言,KCl部分替代NaCl能改善干腌羊火腿的风味品质。

In this study,the hind legs of Inner Mongolia sheep were used as raw materials,KCl partial salt replacement(75%NaCl+25%KCl)and 100%NaCl were used to dry marinate the lamb legs,combined with low temperature air drying,medium temperature fermentation and enhanced high temperature maturation process(the temperatures were gradually increased from 36℃to 40℃with a rate of 2℃per day,and the relative humidity was 90%±5%and mature for 30 days)for dry-cured lamb ham preparation.The effects of salt substitution and enhanced high-temperature technology on physicochemical properties of dry-cured lamb ham were studied by measuring the moisture contents,water activity,salt contents,nitrite contents and color changes during processing,and then Gas Chromatography-Mass Spectrometry(GC-MS)was used to analyze the variation of volatile flavor substances in dry-cured lamb ham.The results showed that the trends of physicochemical indices were similar between salt substitution and salt group during the processing of lamb ham,in which KCl salt substitution could significantly reduce the contents of salt and nitrite in the final products(P<0.05).The overall brightness of ham in the two groups showed a downward trend,and the a^(*)values were first decreased and then increased,while the b^(*)values showed an overall increasing trend,indicating that the partial salt substitution of KCl could reduce the sodium contents by 25%without affecting the color of dry-cured lamb ham,which presented good sensory acceptability.The results of GC-MS showed that 25%KCl salt replacement combining high temperature enhancement could promote the formation of volatile compounds from carbohydrate and amino acid metabolism,β-lipid oxidation and esterification,significantly increase the contents of 3-methylbutyric acid,3-methylbutyric aldehyde,alkanes,olefin and esters,and reduce the relative contents of sulfide.In general,KCl partial salt substitution could improve the flavor qualities of dry cured lamb ham.