Characteristics,Stability, and Release of Peanut Sprout Extracts in Powdered Microcapsules by Spray Drying

This study was carried out to investigate the characteristics of powdered microcapsules from peanut sprout extracts prepared by spray drying. The microcapsules were made from medium-chain triglyceride (MCT) as primary coating material and whey protein concentrate (WPC) or maltodextrin (MD) as selected secondary coating materials. The microcapsule studies conducted were microphotograph, scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR), particle size, moisture contents, sorption, zeta potential, storage stability, and in-vitro study. The surface of microcapsules coated with WPC were rough and smooth, and particle size ranged from 2.86 to 8.59 µm. An FT-IR study revealed that absorption bands at 1,537 and 1,657 cm^?1 of microcapsules can be attributed to the protein amide I and II bands of WPC overlapped by the conjugated C?C. The moisture content was 1.33% in the microcapsules coated with WPC. The moisture sorption increased until 18% at the 90% RH. The yield of peanut sprout extracts from microcapsules was 89.01%. In the in-vitro study, the microcapsules released 2.48 and 6.01% at pH 2.0 and 4.0, respectively, in simulated-gastric fluid, and 61.07 and 89.24% at pH 6.0 and 8.0, respectively, in simulated-intestinal fluid. The preservation rate of the microcapsules dropped down to 60.43% from 89.01% during six months of storage. The stability of peanut sprout extracts in the microcapsules was over 80% at 4 and 20°C during 10-day storage. The zeta-potential of microcapsules was stable with ?30 mV. Based on the data obtained from the present study, the powdered peanut-sprout-extract microcapsules coated with WPC exhibited high stability during storage. Therefore, the powdered microcapsules by spray drying may be useful as a functional ingredient.     

Quality enhancement and microbial reduction of mung bean (Vigna radiata) sprouts by non-thermal plasma pretreatment of seeds

Mung bean (Vigna radiata) sprouts are widely consumed worldwide due to their high nutritional value. However, the low yield and microbial contamination of mung bean sprouts seriously reduces their economic value. This study investigates the effects of non-thermal plasma on the quality and microbial reduction of mung bean sprouts by pretreatment of seeds in water for different times (0, 1, 3 and 6 min). The quality results showed that short-time plasma treatment (1 and 3 min) promoted seed germination and seedling growth, whereas long-time plasma treatment (6 min) had inhibitory effects. Plasma also had a similar dose effects on the total flavonoid and phenolic contents of mung bean sprouts. The microbiological results showed that plasma treatment achieved a reduction of native microorganisms ranging from 0.54 to 7.09 log for fungi and 0.29 to 6.80 log for bacteria at 96 h incubation. Meanwhile, plasma treatment could also efficiently inactivate artificially inoculated Salmonella typhimurium (1.83–6.22 log) and yeast (0.53–3.19 log) on mung bean seeds. The results of seed coat permeability tests and scanning electron microscopy showed that plasma could damage the seed coat structure, consequently increasing the electrical conductivity of mung bean seeds. The physicochemical analysis of plasma-treated water showed that plasma generated various long- and short-lived active species [nitric oxide radicals (NO·), hydroxyl radicals (·OH), singlet oxygen (1O2), hydrogen peroxide (H2O2), nitrate (${{\rm{NO}}}_{3}^{-}$), and nitrite (${{\rm{NO}}}_{2}^{-}$)] in water, thus the oxidizability, acidity and conductivity of plasma-treated water were all increased in a treatment time-dependent manner. The result for mimicked chemical mixtures confirmed the synergistic effect of activity of H2O2, ${{\rm{NO}}}_{3}^{-}$ and ${{\rm{NO}}}_{2}^{-}$ on bacterial inactivation and plant growth promotion. Taken together, these results imply that plasma pretreatment of mung bean seeds in water with moderate oxidizability and acidity is an effective method to improve the yield of mung bean sprouts and reduce microbial contamination.     

两种粉碎机型式对鹰嘴豆芽超微粉食用品质的影响

目的 探讨粉碎机型式对鹰嘴豆芽超微粉食用品质的影响。方法 利用碾轧式超微粉碎机和行星式球磨仪对鹰嘴豆芽进行超微粉碎,检测鹰嘴豆芽超微粉的营养成分含量以及物理性质,探究功能成分及抗氧化活性的变化。结果 处理后的两种粉体平均粒径减至常规粉体的10.19%、8.53%;与碾轧式超微粉相比,行星式球磨粉的持水力、水溶性和溶胀力分别是其1.49、1.50和1.43倍,休止角、滑角显著增加（p＜0.05）,L值升高和a、b值降低更明显（p＜0.05）;行星式球磨粉获得多于碾轧式超微粉10.30%、15.61%的酚类物质。碾轧式超微粉营养成分含量较多（脂肪6.17%、还原糖3.82%）,具有较强的抗氧化活性。结论 两种粉碎机对鹰嘴豆芽粉具有不同的影响,行星式球磨仪促进酚类物质含量上升更显著（p＜0.05）,碾轧式超微粉碎机更好地保留粉体流动性和营养功能性。     

高效液相色谱-串联质谱测定豆芽中6-苄氨基嘌呤方法的研究

建立了豆芽中的6-苄氨基嘌呤的高效液相色谱-串联质谱法（HPLC-MS/MS）定量定性分析方法.样品经酸化甲醇2次提取后,在高效液相色谱-串联质谱仪（HPLC-MS/MS）选择反应监测（MRM）模式下测定.采用质谱定性,外标法定量.色谱柱为资生堂MGⅡ-C18（5μm2.1 mm ×150mm）色谱柱,以0.1％甲酸水-0.1％甲酸甲醇为流动相进行梯度洗脱,流速0.3 mL/min.在优化的实验条件下,得到了较宽的线性范围和较低的定量检出限：线性范围为0.1～20.0μg/L,线性相关系数在0.999以上,定量限为：7.3 μg/kg.方法的回收率和重现性较好,回收率为98.3％～106.9％之间,相对标准偏差（RSD）在1.16％～3.56％之间.该方法操作简单高效、灵敏度高、结果准确可靠,可应于豆芽中6-苄氨基嘌呤的定量及确证分析.     

史前文化时期的酿酒(一)酒的起源

酒的起源和发展应在人类社会进入到农业社会时期。从仰韶文化遗址(公元前5000年～公元前3000年)考证，当时已有酒的存在，并证明我国最早的酒是谷芽酒。这时期出土了不少酿酒发酵容器，最具有代表性的为小口尖底瓮。这种酒具有防止酒的酸败、促进酒的澄清作用。小口尖底瓮在古巴比伦及古埃及均有发现，用于酿造麦酒和葡萄酒。(陶然)     

UV-C处理抑制马铃薯贮藏期发芽及相关机理研究

为提高马铃薯的食用安全性和贮藏品质,本实验研究了短波紫外线(ultraviolet C,UV-C)处理对马铃薯贮藏过程中发芽品质的影响。采用10 kJ/m2 UV-C对马铃薯进行一次处理(贮藏前),二次处理(贮藏前及中期),并测定发芽率、还原糖、苯丙氨酸解氨酶、多酚、赤霉素、α-茄碱等指标。结果表明,UV-C处理能够有效抑制马铃薯贮藏过程中的发芽,同时延缓赤霉素和α-茄碱的上升。二次处理组贮藏至90 d时,薯皮和肉质部分的α-茄碱含量仅为对照组的71.09%、65.75%;105 d时发芽率为68.78%,还原糖含量为0.40%,失重率为4.71%,贮藏品质均优于对照组和一次处理组。综上所述,当处理剂量和方式适宜时,UV-C可在马铃薯发芽控制及品质保持方面获得良好效果,其中二次处理更具优势。