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961.
Meng-Ni Zhao Fang Zhang Lin Zhang Bing-Jie Liu Xiang-Hong Meng 《International Journal of Food Science & Technology》2019,54(8):2624-2631
This study was conducted aiming at improving the quality of jujube juice by mixed fermentation of lactobacilli. Selection of favourable lactobacilli and addition of nitrogen sources were explored as an efficient method to improve the viability of probiotic in jujube juice. After fermentation, the viability increased to 9.15 ± 0.10 Log CFU mL−1, while the content of lactic acid increased to 5.61 ± 0.03 mg mL−1. The total phenolic and total flavonoid content were 2663.03 ± 11.95 μg mL−1 and 163.95 ± 0.47 μg mL−1 respectively. Moreover, the stability of fermented jujube juice during refrigeration was investigated, which showed that the viability dropped to 8.84 ± 0.6 Log CFU mL−1 and the concentration of lactic acid slowly increased to 6.51 ± 0.04 mg mL−1; the ABTS value showed a 4.26% reduction and FRAP value did not significantly (P < 0.05) change during refrigerated storage. In addition to the existing knowledge, our data aid to the future applications of the jujube as a potential ingredient in novel probiotic foods formulation. 相似文献
962.
Rayssa Julliane de Carvalho Geany Targino de Souza Pedrosa Maísa Gomes Chaves Janaina Maria Batista de Sousa Evandro Leite de Souza Rafael Pagán Marciane Magnani 《International Journal of Food Science & Technology》2019,54(6):2309-2318
This study determined the compromised acceptance threshold (CAT) and rejection threshold (RT) of Mentha piperita L. essential oil (MPEO) in cajá, guava and mango juices. The MPEO concentrations below the RT values were evaluated alone or combined with mild heat treatment (MHT; 54 °C) to inactivate ≥5-log10 of Escherichia coli O157:H7 and Salmonella Enteritidis PT 4 in the same juices. The CAT of MPEO varied from 0.30 to 0.32 μL mL−1, while the RT was 1.34 or 1.36 μL mL−1 in the tested juices. Only concentrations of MPEO close, or higher than the RT caused ≥5-log10 reductions in the tested pathogens in cajá, guava and mango juices. Combined with MHT, concentrations of MPEO below the RT reduced ≥5-log10 of both pathogens in juices. These findings indicate that MPEO concentrations below the RT in combination with MHT is a feasible preservation technology to ensure the safety of tropical fruit juices. 相似文献
963.
Janam K. Pandya Maryssa DeBonee Maria G. Corradini Mary Ellen Camire David Julian McClements Amanda J. Kinchla 《International Journal of Food Science & Technology》2019,54(12):3196-3204
Tocotrienols are members of the vitamin E family that provide many nutritional benefits. Developing tocotrienol-fortified functional foods introduces vitamin E into consumers diets without changing their food habits. The purpose of this study was to compare the stability of tocotrienols in bulk form and six food matrices at a fixed dose (40 mg kg−1) under accelerated and conventional storage conditions. The delta- and gamma-tocotrienol content was measured using HPLC, and the sensory attributes were evaluated using triangle and hedonic tests. Tocotrienol in bulk powder was less stable under stressed conditions than in bulk oil, with the powders having approximately 40% and 80% reduction in δ- and γ- after storage and bulk oil with no significant degradation. HPLC analysis demonstrated that tocotrienol content remained unchanged in dry mix lemonade, yogurt, raw and UHT milk, and margarine over time; however, complete degradation of γ- and partial degradation (up to 50%) of δ-tocotrienol was observed in bread during ambient and stressed storage conditions. A significant decrease in the δ-tocotrienol relative concentration was also observed in HTST processed milk samples. Tocotrienol addition was not perceived, and no significant difference in the product attributes and overall liking was reported in the discrimination sensory testing. 相似文献
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967.
金属板料成形工艺CAD／CAM智能化集成研究 总被引：2，自引：0，他引：2
根据现行发展状况,探讨了金属板料成形CADCAE智能化集成的必要性和可行性,分析了其中要解决的一些关键技术,提出了实现CADCAE智能化集成的方法。 相似文献
968.
969.
介绍了组合机床夹具设计的研究状况,分析了企业开发应用组合机床夹具智能设计系统的必要性及该系统实现存在的难点。在分析构建该智能设计系统的系统框架的基础之上,利用三维设计软件UG的OPEN二次开发功能及其WAVE技术的相结合,开发实现了该系统,并对实现该系统的关键技术进行了详细的阐述,主要包括夹具知识库的建立及夹具体等非标准灵活性零件的设计过程等。最后进行了工程应用,结果表明该系统能提高组合机床夹具设计的效率和质量。 相似文献
970.
结合KBE技术的发展以及在机械设计中的应用,提出了一种面向产品设计流程的智能化设计方法.结合基于实例推理的设计技术和基于知识的参数化设计技术的优势,将知识融入设计流程,在总体设计、详细设计等产品设计全过程实现智能化快速设计. 相似文献