酥梨膏不同贮藏期的品质比较

Comparison of the Quality of Suli Pear Paste Stored for Different Periods

摘要:

该研究为了解酥梨膏长期贮藏品质变化规律，明确酥梨膏适宜贮藏期限。该研究以不同贮藏期的酥梨膏为试材，通过测定酥梨膏的菌落总数，色差值、pH值、总糖、氨基酸态氮、总酚等外观色泽、品质指标以及挥发性成分，并采用主成分和相关性分析对各贮藏期的酥梨膏指标进行品质评价和分析，探究贮藏时长对酥梨膏品质影响。结果表明：不同贮藏时期的酥梨膏菌落总数在37.0~67.0 CFU/mL之间，均符合食品安全微生物限量标准，贮藏32个月之内的酥梨膏体系较稳定，沉淀率、澄清度、稳定性、云度值分别为2.29%、18%、0.87%和1.62；贮藏24个月酥梨膏可保持较好品质，总酚（2 060.68 mg/L）、总黄酮（754.33 mg/L）、可溶性蛋白(67.19 mg/L)含量显著增加（P<0.05），DPPH•清除率（91.62%）、氨基酸态氮（124.93 mg/L）与贮藏10个月差异不显著（P>0.05），pH值（4.71）、总糖（75.36%）与贮藏2个月差异不显著（P>0.05）；随着贮藏期延长，酥梨膏中挥发性成分种类增加，贮藏24个月之内刺激性挥发性成分不是特征物质。综合分析，贮藏24个月，酥梨膏能保持较好的品质，是酥梨膏适宜的贮藏期限。

Abstract:

This research aimed to understand the changing trend of the long-term storage quality of Suli pear paste, and determine its suitable storage period. In this research, the effects of storage period on the quality of the paste were evaluated and analyzed through measuring the total number of colonies, color difference value, pH value, total sugar, amino acid nitrogen, total phenolic content, and other appearance color, nutritional quality indexes and volatile components of the paste, and principal component analysis and correlation analysis were performed on the indexes of the paste stored for different periods. The results showed that the total number of colonies of Suli pear paste after being stored for different storage periods were 37.0~67.0 CFU/mL, which all complied with the food safety microbial limited standard. The Suli pear paste system after 32 months of storage was relatively stable, with the values of precipitation rate, clarity, stability and cloudiness value were 2.29%, 18%, 0.87% and 1.62, respectively. After 24 months of storage, the quality of Suli pear paste remained good, with the contents of total phenolics (2 060.68 mg/L), total flavonoids (754.33 mg/L) and soluble protein (67.19 mg/L) increased significantly (P<0.05). The DPPH clearance rate (91.62%) and amino acid nitrogen (124.93 mg/L) were insignificantly different from those stored for 10 months (P>0.05); The pH value (4.71) and total sugar (75.36%) were insignificantly different from those stored for 2 months (P>0.05). With the extension of storage period, the number of different types of volatile components in the paste increased, and within 24 months of storage, the irritating volatile substances were not the characteristic substances. Comprehensive analysis showed that the pear paste could maintain better quality over a 24-month storage, thus, a storage period of 24 months is appropriate for Suli pear paste.