不同杀菌方式对桑葚原汁品质的影响

以桑葚原汁为材料，对比分析了巴氏杀菌、超高温瞬时杀菌（ultra high temperature treated，UHT）以及静态超高压杀菌（ultra high hydrostatic pressure，UHHP）3 种不同的杀菌处理对桑葚原汁的微生物、品质和香气成分的影响。结果表明：3 种杀菌方式处理的桑葚原汁均符合GB 19297-2003《果、蔬汁饮料卫生标准》要求，UHT杀菌更彻底，未有微生物检出。与未杀菌桑葚原汁相比，可溶性固形物、总糖含量经巴氏杀菌和UHT处理后都出现了较显著下降趋势（P＜0.05）；UHHP处理对花色苷含量影响最大；总酚含量、类黄酮含量以及抗氧化能力经过不同杀菌处理后表现出不同程度的下降，UHHP处理影响最小。采用固相微萃取-气相色谱-质谱联用技术对未杀菌桑葚原汁及巴氏杀菌、UHT和UHHP桑葚原汁香气成分进行分析，分别鉴定出52、42、44、49 种挥发性香气成分。UHHP桑葚原汁各主要香气成分与未杀菌桑葚原汁最为接近。UHHP技术不仅具有良好的杀菌效果，而且能较好的保持桑葚原汁的品质。

Effect of Sterilization Methods on the Quality of Mulberry Juice

A comparative analysis of the effect of three different sterilization methods, namely pasteurization, ultra high
temperature treatment (UHT) and ultra high hydrostatic pressure (UHHP), on the microbial load, quality and aroma
composition of mulberry juice was carried out in the present investigation. The results indicated mulberry juice met the
requirement of commercial sterilization according to the Chinese national standard GB 19297—2003 after being sterilized
by the above three methods, especially by UHT treatment, which achieved complete microbial inactivation. Compared
with the blank group, soluble solids and total sugar contents significantly decreased (P < 0.05) after pasteurization and
UHT treatment. UHHP treatment had the largest impact on the content of anthocyanins. The content of total phenol
and flavonoids, and antioxidant capacity declined to different extents after different sterilization treatments, and UHHP
treatment changed the least. As indicated by solid-phase micro-extraction (SPME) coupled with gas chromatography-mass
spectrometry (GC-MS), 52, 42, 44 and 49 volatile aroma components were identified in the blank control and mulberry
juice subjected to pasteurization, UHT and UHHP treatments, respectively. UHHP treatment was the most close to the blank
group as far as the main aroma components were concerned. In general, UHHP technology has good sterilization efficiency
while effectively maintaining the quality of mulberry juice.