Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activit...Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).展开更多
Plants show different growth responses to N sources supplied with either NH4+ or NO-3 . The uptake of different N sources also affects the rhizosphere pH and therefore the bioavailability of soil phosphorus, particula...Plants show different growth responses to N sources supplied with either NH4+ or NO-3 . The uptake of different N sources also affects the rhizosphere pH and therefore the bioavailability of soil phosphorus, particularly in alkaline soils. The plant growth, P uptake, and P availability in the rhizosphere of oat (Avena nuda L.) grown in hydroponics and in soil culture were investigated under supply with sole NH4+ -N, sole NO3- -N, or a combination. Sole NO3- -fed oat plants accumulated more biomass than sole NH+4 -fed ones. The highest biomass accumulation was observed when N was suppliedw ith both NH4+ -N and NO3- -N. Growth of the plant root increased with the proportion of NO3- in the cultural medium. Better root growth and higher root/shoot ratio were consistently observed in NO3- -fed plants. However, root vigor was the highest when N was supplied with NO3- +NH4+ . NH4+ supply reduced the rhizosphere pH but did not affect P uptake by plants grown in soils with CaHPO4 added as P source. No P deficiency was observed, and plant P concentrations were generally above 2 g kg-1. P uptake was increased when N was supplied partly or solely as NO3- -N, similarly as biomass accumulation. The results suggested that oat was an NO3- -preferring plant, and NO-3 -N was essential for plant growth and the maintenance of root absorption capacity. N supply with NH+4 -N did not improve P nutrition, which was most likely due to the absence of P deficiency.展开更多
文摘Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).
基金Project supported by the National Natural Science Foundation Council of China (No.30660086)the Natural Science Foundation of Inner Mongolia of China (No.200607010302)+2 种基金Hong Kong Research Grants Council (No.2465/05M)Hong Kong University Grants Committee (No.AOE/B-07/99)Hong Kong Baptist University Matching Research Fund.
文摘Plants show different growth responses to N sources supplied with either NH4+ or NO-3 . The uptake of different N sources also affects the rhizosphere pH and therefore the bioavailability of soil phosphorus, particularly in alkaline soils. The plant growth, P uptake, and P availability in the rhizosphere of oat (Avena nuda L.) grown in hydroponics and in soil culture were investigated under supply with sole NH4+ -N, sole NO3- -N, or a combination. Sole NO3- -fed oat plants accumulated more biomass than sole NH+4 -fed ones. The highest biomass accumulation was observed when N was suppliedw ith both NH4+ -N and NO3- -N. Growth of the plant root increased with the proportion of NO3- in the cultural medium. Better root growth and higher root/shoot ratio were consistently observed in NO3- -fed plants. However, root vigor was the highest when N was supplied with NO3- +NH4+ . NH4+ supply reduced the rhizosphere pH but did not affect P uptake by plants grown in soils with CaHPO4 added as P source. No P deficiency was observed, and plant P concentrations were generally above 2 g kg-1. P uptake was increased when N was supplied partly or solely as NO3- -N, similarly as biomass accumulation. The results suggested that oat was an NO3- -preferring plant, and NO-3 -N was essential for plant growth and the maintenance of root absorption capacity. N supply with NH+4 -N did not improve P nutrition, which was most likely due to the absence of P deficiency.
