Minerals in vitro bioaccessibility and changes in textural and structural characteristics of uncooked pre-germinated brown rice influenced by ultra-high pressure

Ultra-high pressure (UHP) is considered as an effective processing method to enhance micronutrients utilization efficiency in germinated brown rice (GBR), but there is little information available for the effects of UHP treatments on mineral bioaccessibility and related structural characteristics. Therefore, this work examined the changes induced by UHP in the in vitro bioaccessibility of selected minerals and structural and textural properties at pressures, as well as their potential relationship. UHP treatments were applied at 100, 300 and 500 MPa for 10 min, and 0.1 MPa as control. Proximate analysis showed that free fatty acids (FFA) and moisture in GBR greatly increased after UHP treatment. Three representative minerals with different levels were chosen to assess the bioaccessibility, including phosphorus (P), magnesium (Mg) and manganese (Mn). The results demonstrated that the minerals bioaccessibility, measured by percentage solubility, were the highest when at 300 MPa whereas it decreased at 500 MPa. Correspondingly, microstructure imaging by scanning electron microscope (SEM) showed that the gelatinization of starch granule occurred at 300 MPa and it became more obvious when increased to 500 MPa. Starch gelatinization significantly lowered the hardness of GBR grains, simultaneously accompanied with the decrease of cohesiveness, gumminess and resilience through texture profile analysis (TPA). Multivariate analysis by principal component analysis and canonical correspondence analysis indicated a highly intra-associated (p < 0.01) TPA parameters and a close correlation between the bioaccessibility and hardness, chewiness and springiness. These results provide information on minerals bioaccessibility and structural properties of uncooked GBR after UHP treatment, which could lay the foundation for further elucidating the correlation between structure and micronutrients bioaccessibility.     

Lowland rice response to potassium fertilization and its effect on N and P uptake

Not much is known about the response of lowland rice to K fertilization under Brazilian conditions. A field experiment was conducted during four consecutive years to determine the response of three lowland rice (Oryza sativa L.) cultivars to K fertilization on a Low Humic Gley soil. In the first two years, K was broadcast at rates of 0, 42, 84, 126, and 168 kg K ha^–1. In the last two years K rates were reduced to 0, 25, 50, 75, and 100 kg K ha^–1 and applied in a band. Potassium significantly (P < 0.01) increased grain yields but the response varied from cultivar to cultivar and year to year. Yield responses to K fertilization were superimposed on a general trend of increasing grain yields across the four growing seasons. Mean grain yields increased 14.3% with broadcast application of K in the first two years and 10.4% with banded application of K in the last two years when compared to the control treatments. Extractable soil K increased with K application rate and decreased with soil depth. Potassium was rapidly removed from the soil and yearly broadcast or banded application of K can be expected to result in a significant increase in grain yield of lowland rice in these soils.     

Degradation of cell wall material of apple and wheat bran by human faecal bacteria in vitro

The effect of the structures of plant cell walls and their component polymers on the degradability of dietary fibre by bacteria of the human colon was investigated by inoculating culture media containing cell wall materials of apple and wheat bran with slurries of human faeces which were then incubated for periods of up to 72 h. In the apple substrates the amounts of pectic polysaccharides were extensively depleted after 12 h, and after 24 h over 90% of the initial carbohydrate had been degraded. Material which remained after incubation was probably comprised of highly branched fragments of rhamnogalacturonans, cross-linked by phenolics and proteins, highly branched fragments of cross-linked xyloglucans, and degraded cellulose. In wheat bran the aleurone layer was preferentially degraded, but the glucuronoarabinoxylans, which were cross-linked by phenolic groups, and the lignified outer layers of the bran were very resistant to attack. Bacteria adhered mainly to the broken or damaged surfaces of the plant cell walls, and in the more resistant tissues only penetrated the intercellular regions.     

Effect of steam distillate extract of resistant wild riceOryza officinalis on behavior of brown planthopperNilaparvata lugens (Stal) (Homoptera: Delphacidae)

Rice plant volatiles extracted as steam distillates significantly affected the behavior of the brown planthopperNilaparvata lugens (Stal). In a choice test, significantly more females settled and fed on tillers of a susceptible rice variety, Taichung Native 1 (TN 1), sprayed with acetone or untreated TN 1 plants than on TN 1 tillers sprayed with the extracts of resistant wild riceOryza officinalis. O. officinalis steam distillate was highly toxic to first-instar nymphs ofN. lugens. Ingestion and assimilation of food by females was significantly reduced on TN 1 plants sprayed withO. officinalis distillate compared to TN 1 plants sprayed with acetone. Application of0. officinalis distillate on TN 1 plants adversely affected hatchability of eggs ofN. lugens.     

ECMP麻浆用于配抄稻草板护面纸板的研究

研究了将ECMP麻浆配用国内废纸浆,抄造稻草板护面纸板的可行性,并对外层、里层施胶度、以及干燥前压榨压力、经济成本等进行了讨论,结论认为:ECMP麻浆配抄稻草板护面纸板可以满足护面纸企业标准要求,并可取得良好的经济效益。     

大米淀粉制备及其综合利用研究进展

大米淀粉以其独特物理化学性质广泛用于食品、纺织等行业,该文综述近年来大米淀粉制备及其性质和应用研究概况。     

黑血糯米粉的物化性质研究

研究了黑血糯的营养成分,黑血糯淀粉的颗粒形貌和结晶性质,糊的凝沉性,冻融稳定性以及糊的粘度曲线。结果表明黑血糯的蛋白质含量高,氨基酸组成合理,结晶度高,糊化温度高,糊的凝沉性低,冻融稳定性一般。可知酸、碱可以促进黑血糯的糊化,而蔗糖则有一定的抑制作用。     

米糠油生理功能及制取工艺的研究

概述了米糠油的营养价值及生理功能,详细介绍了米糠制油技术及米糠油精炼技术,并分析了各种米糠油精炼技术的优缺点.     

复合面窝粉的研制

以大米、黄豆为主要原料,适当添加变性淀粉等辅料,采用超微粉碎方法、复配技术和正交试验,优化配方,开发工艺简单、使用方便、营养丰富的大米复合面窝粉,并研究面窝粉的储藏性能.结果表明,将100～140目大米粉和黄豆粉按质量比8:2的比例,并添加0.8%的泡打粉、5%的面粉、1%的变性淀粉AW-1000、2.5%的食盐,混合均匀,制成复合面窝粉.使用时添加150%的水和辅料,在适宜的工艺下油炸成型,即可生产出品质优良的面窝.面窝粉储藏12个月后,真空包装的感官品质较好,但总茵数略高于常态包装.     

解析泰国大米成功之道

泰国大米走向成功的经验有四点:一是推行务实的稻米政策;二是采用严格的大米标准;三是贯彻了完善的质量管理;四是运用灵活的大米经营策略。泰国大米成功经验对我国稻米产业的发展提供了范例。