不同澄清剂对番石榴汁品质的影响

以番石榴为实验材料,选用明胶、壳聚糖、皂土、硅藻土四种澄清剂对番石榴汁进行单因素试验,以番石榴汁的透光率、总色差值(L*、a*、b*、ΔE*)、可溶性固形物含量为指标,研究四种澄清剂对番石榴汁澄清效果和感官品质的影响,以及四种澄清剂对番石榴汁抗氧化性的影响和对番石榴汁中总黄酮、Vc含量的影响。结果表明,在25℃下使用0.1 g/100mL明胶作澄清剂澄清30分钟后的番石榴汁的品质最佳。此工艺加工后的番石榴汁透光率为4.15%,可溶性固形物含量为1.70%,明暗度L*为55.64,红绿值a*为8.38,黄蓝值b*为9.75,总色差值ΔE*为24.78,对DPPH自由基清除能力为92.99%,对羟基自由基清除能力为52.37%,对铁离子的还原能力为76.10%,澄清后的番石榴汁中Vc含量为3.460 mg/mL,总黄酮含量为1.201μg/mL。

案例教学法在“生物化学”课程教学中的应用——以川菜“回锅肉”为例

“生物化学”是烹饪营养与教育专业的专业基础必修课。课堂教学中应加强生物化学与专业的融合,通过引入食品工业及餐饮行业的具体案例调动学生课堂学习的兴趣,让学生尽早认识到专业基础课在未来职业中的重要作用,进而提升课堂教学质量。首先分析“生物化学”传统教学出现的问题,然后以川菜“回锅肉”为例,探讨案例教学法在“生物化学”课程教学中的作用。

A thermostable serralysin inhibitor from marine bacterium Flavobacterium sp. YS-80-122

Serralysin inhibitors have been proposed as potent drugs against many diseases and may help to prevent further development of antibiotic-resistant pathogenic bacteria. In this study, a novel serralysin inhibitor gene, lupI, was cloned from the marine bacterium Flavobacterium sp. YS-80-122 and expressed in Escherichia coll. The deduced serralysin inhibitor, LupI, shows 〈40% amino acid identity to other reported serralysin inhibitors. Multiple sequence alignment and phylogenetic analysis of LupI with other serralysin inhibitors indicated that LupI was a novel type of serralysin inhibitor. The inhibitory constant for LupI towards its target metalloprotease was 0.64mol/L. LupI was thermostable at high temperature, in which 35.6%-90.7% of its inhibitory activity was recovered after treatment at 100℃ for 1-60 min followed by incubation at 0℃. This novel inhibitor may represent a candidate drug for the treatment of serralysin-related infections.

基于OBE理念的“食品理化检验”课程的改革与实践——以四川旅游学院食品质量与安全专业为例

“食品理化检验”是食品质量与安全专业的专业核心课程,旨在培养学生对食品中的和卫生营养相关的指标的分析检验能力。为提高教学效果,基于OBE理念,对标本专业的毕业要求,通过调整课程教学内容、优化师资结构、新购检测仪器等改革与实践措施,改进了教学质量,并建立了基于OBE理念的考核模式,学生综合素质提升效果明显。该课程的改革与实践可为其他相关专业类课程的教学组织和持续改进提供参考。