Development and quality evaluation of a cereal-based breakfast product from yellow maize (Zea mays), sesame (Sesamum indicum) and mushroom (Pleurotus ostreatus) flour blends

Composite flours were prepared from blends of yellow maize (Zea mays), sesame seed (Sesamum indicum) and oyster mushroom (Pleurotus ostreatus) powder in the ratio of 80:20:0; 75:20:5; 70:20:10; 65:20:15 and 60:20:20, respectively to produce the cereal-based breakfast product coded as YSB, SMB, TMB, PMB and OMB with YSB as the control. The breakfast cereals were produced by hydration and toasting of yellow maize and sesame to 160°C for 25 min and blended together with oven-dried and packaged oyster mushroom. The developed products were analysed for proximate, vitamins, minerals and sensory properties. The proximate composition (%) of different blends ranged as moisture (4.07–7.08), ash (3.09–2.28), crude fat (16.04–12.83), crude fibre (4.30–8.22), protein (16.14–22.54), carbohydrate (56.34–47.04) and energy (434.34–393.83 Kcal). Vitamin A (7.99–5.98 mg/100 g), vitamin B₁ (0.08–0.42 mg/100 g), vitamin B₂ (0.06–0.15 mg/100 g), vitamin B₃ (1.91–4.52 mg/100 g) and vitamin C (3.55–3.32 mg/100 g) were u while minerals (mg/100 g) were calcium (75.31–58.02), potassium (0.65–4.01), magnesium (12.25–12.62), iron (1.21–4.15) and zinc (0.40–1.32). Sensory scores revealed that the cereal-based breakfast product were acceptable to the panellist with oyster mushroom supplementation up to 10%.     

Do metal grain silos benefit women in Kenya,Malawi, Zambia and Zimbabwe?

Metal silos can reduce maize losses during storage in smallholder farm systems, contributing towards international goals of reducing food waste and moving towards Sustainable Development Goal 2, Zero Hunger. However, technologies are introduced into farming systems with complex sets of relationships. These may differentially affect the ability of women and men to secure the expected benefits of metal silos. This, in turn, may affect adoption rates and expected outcomes. To better understand these relationships, a mixed methods study was conducted in Kenya, Malawi, Zimbabwe and Zambia where metal silos were introduced through the Effective Grain Storage Project (EGSP). EGSP distributed 1717 metal silos across the four countries.Quantitative surveys using random sampling were conducted in Kenya (124 respondents) and Malawi (100 respondents) with metal silo owners. Qualitative surveys, using purposive sampling, were conducted in all four countries covering 14 ethnic groups using focus group discussions (360 respondents), key informant interviews (62 respondents), and household case studies (62 respondents). The aim was to understand gendered post-harvest management and storage strategies in traditional systems and to map changes when metal silos were introduced.The findings suggest roles and responsibilities regarding the ownership and management of storage structures are strongly gendered with some differences between ethnic groups and countries. Men benefit more than women from the introduction of metal silos. Ownership of the grain storage facility, and the benefits attached to ownership, can switch from women to men with women having less scope for bargaining over their rights to use the stored grain for their own needs and the benefit of all household members. Women and men fail to fully follow guidelines for effective use of metal silos. They differ in their preferred attributes for their ideal storage system. Whilst some attributes are shared, women’s preferences were sharply differentiated from men in others.     

玉米淀粉对大蒜中大蒜素的包合及其复合物的抑菌活性

以玉米淀粉和鲜大蒜为原料,尝试高速剪切混合制备淀粉-大蒜素复合物,并对其抑菌活性进行评价。结果表明,当高速剪切混合处理时间为40 min,大蒜(干基)/淀粉质量比为3:2时,复合物中大蒜素的含量为1.17±0.02μg/mg,包埋率为89.71%±1.20%。碘结合实验表明,淀粉与大蒜中的大蒜素通过主客体相互作用形成复合物。玉米淀粉经高速剪切混合处理后颗粒形态的变化不大,但是与大蒜共同处理后淀粉颗粒的形态发生较大的变化。形成复合物后淀粉的结晶度降低;淀粉复合物比大蒜粉具有较高的热稳定性。抑菌实验表明,复合物的抑菌活性良好,当大蒜(干基)与玉米淀粉质量比为3:2时,其对E.coli,S.aureus,B.subtilis和S.Typhimurium的抑菌圈直径分别为19.92±0.03、23.02±0.03、34.51±0.20、23.21±0.15 mm。淀粉-大蒜素复合物的形成,提高了大蒜素的生物活性。     

Hypoxia-Responsive Class III Peroxidases in Maize Roots: Soluble and Membrane-Bound Isoenzymes

Flooding induces low-oxygen environments (hypoxia or anoxia) that lead to energy disruption and an imbalance of reactive oxygen species (ROS) production and scavenging enzymes in plants. The influence of hypoxia on roots of hydroponically grown maize (Zea mays L.) plants was investigated. Gene expression (RNA Seq and RT-qPCR) and proteome (LC–MS/MS and 2D-PAGE) analyses were used to determine the alterations in soluble and membrane-bound class III peroxidases under hypoxia. Gel-free peroxidase analyses of plasma membrane-bound proteins showed an increased abundance of ZmPrx03, ZmPrx24, ZmPrx81, and ZmPr85 in stressed samples. Furthermore, RT-qPCR analyses of the corresponding peroxidase genes revealed an increased expression. These peroxidases could be separated with 2D-PAGE and identified by mass spectrometry. An increased abundance of ZmPrx03 and ZmPrx85 was determined. Further peroxidases were identified in detergent-insoluble membranes. Co-regulation with a respiratory burst oxidase homolog (Rboh) and key enzymes of the phenylpropanoid pathway indicates a function of the peroxidases in membrane protection, aerenchyma formation, and cell wall remodeling under hypoxia. This hypothesis was supported by the following: (i) an elevated level of hydrogen peroxide and aerenchyma formation; (ii) an increased guaiacol peroxidase activity in membrane fractions of stressed samples, whereas a decrease was observed in soluble fractions; and (iii) alterations in lignified cells, cellulose, and suberin in root cross-sections.     

增效过磷酸钙的增效机制及其对玉米生长的影响

利用猪毛、风化煤和腐植酸钠的水解液为增效剂制备了一种增效过磷酸钙,探讨了增效过磷酸钙的增效机制及其对玉米生长的影响。结果表明,蒸馏水浸提条件下,增效过磷酸钙能减缓水溶磷的释放,具备较高的pH值缓冲性。与普通过磷酸钙相比,增效过磷酸钙处理的玉米生物量平均增加了41.9%,吸磷量和吸钙量分别增加了61.7%和27.8%,根系活力增加了24.3%。该研究结果对过磷酸钙生产的技术改进具有指导意义。     

新采收玉米籽粒中水分状态对淀粉热特性的影响

以2种中国东北地区玉米郑单958(Zd958)和先玉335(Xy335)为研究对象,采用低场强核磁共振技术(low field nuclear magnetic resonance,LF-NMR)和差示扫描量热技术分析新玉米采后60 d内籽粒水分迁移和分布变化,及其对淀粉热特性影响。结果表明,东北新采收玉米采后水分T_2弛豫时间和水分分布呈显著变化(P0.05),2种玉米淀粉凝胶焓值在40 d达到最高分别为18.54 J/g和15.06 J/g,结合水弛豫时间T_(21)与籽粒水分含量呈极显著相关(P0.01),结合水相对面积A_(21)与籽粒水分含量呈极显著负相关(P0.01),A_(21)与凝胶吸热焓值(?H)呈显著相关(P0.05),表明水分迁移和分布是影响淀粉分子晶体结构变化原因之一,利用LF-NMR技术可以有效分析采后籽粒内部水分动态变化,及其对淀粉功能特性影响。