Crops ›› 2019, Vol. 35 ›› Issue (6): 57-65.doi: 10.16035/j.issn.1001-7283.2019.06.009

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Changes of Cooking and Eating Quality and Its Correlation with Mineral Element Content in Polished Rice under Different Nitrogen Grain Fertilizer Levels

Shi Lü,Xue Yaguang,Wei Yafeng,Li Bo,Shi Xiaoxu,Liu Jian   

  1. Jiangsu Yanjiang Area Institute of Agricultural Sciences/Key Laboratory of Recycling Agriculture of Nantong, Rugao 226541, Jiangsu, China
  • Received:2019-08-07 Revised:2019-10-23 Online:2019-12-15 Published:2019-12-11
  • Contact: Jian Liu

Abstract:

In order to study the changes of mineral elements content and cooking and eating quality of polished rice under different nitrogen grain fertilizer levels, and determine the correlation between protein, cooking and eating quality and mineral elements. Yangdao 6 and Nanjing 9108 were used as test materials, and three levels of nitrogen grain fertilizer were set, as the control (N1: 0kg/hm 2), medium nitrogen grain fertilizer (N2: 90kg/hm 2) and high nitrogen grain fertilizer (N3: 150kg/hm 2), and the content of mineral elements and the cooking and eating quality of the rice were measured. The results showed that the nitrogen content in polished rice increased with the increasing of nitrogen grain fertilizer level. With the increasing of nitrogen grain fertilizer level, the content of major elements P, K and secondary elements Ca, Mg decreased significantly, while the content of trace elements Fe, Mn, Zn, Cu increased significantly. Simultaneously, the Mg/K, Mg/(N?AC?K) and amylose content also showed a decreasing trend, and the protein content increased significantly. In addition, the peak viscosity, hot viscosity and breakdown of the RVA spectrum eigenvalues gradually decreased while the consistence and setback showed an increasing trend, and the taste value deteriorated significantly at the same time. Correlation analysis found that the protein content was significantly or extremely significantly positively correlated with trace elements, and had significant or extremely significant negative correlation with major and medium elements and taste value. Mg/K and Mg/(N?AC?K) were closely related to the characteristic values of RVA, which were beneficial to the improvement of cooking and eating quality. It can be seen that in the production, the nitrogen fertilizer should be controlled in the appropriate range according to local conditions, so as to improve the mineral nutrient content and cooking and eating quality of rice.

Key words: Rice, Polished rice, Nitrogen grain fertilizer, Mineral element, Protein, Cooking and eating quality

Table 1

Varieties difference of Mg, K, N content and AC content in polished rice under different nitrogen grain fertilizer levels"

品种Variety 处理Treatment Mg(μg/g) K(μg/g) AC(%) N(%) Mg/K Mg/(N·AC·K)
扬稻6号 N1 252.89±1.06a 761.52±2.96a 17.36±0.13a 1.05±0.03c 0.3321±0.0027a 0.0182±0.0005a
Yangdao 6 N2 182.53±2.91b 572.84±11.78b 16.98±0.15b 1.39±0.11b 0.3187±0.0015b 0.0135±0.0001b
N3 167.84±0.16c 560.10±0.94b 16.49±0.10c 1.54±0.08a 0.2997±0.0015c 0.0118±0.0002c
南粳9108 N1 236.28±1.93a 666.11±0.74a 19.21±0.20a 1.09±0.04c 0.3547±0.0025a 0.0170±0.0002a
Nanjing 9108 N2 204.78±0.46b 625.38±1.14b 18.14±0.19b 1.31±0.12b 0.3275±0.0001b 0.0137±0.0001b
N3 178.53±0.88c 606.91±1.02b 17.46±0.08c 1.49±0.21a 0.2942±0.0010c 0.0113±0.0001c
F值Fvalue 品种Variety 37.31** 0.21ns 263.61** 3.24ns 78.40** 13.16*
氮素粒肥
Nitrogen grain fertilizer
2 270.47** 803.58** 86.09** 254.79** 760.84** 612.62**
品种×氮素粒肥
Variety×Nitrogen grain fertilizer
167.22** 278.71** 10.51* 4.68ns 69.24** 9.88*

Table 2

Varieties difference of P, Ca content and trace elements Fe, Mn, Zn, Cu content in polished rice under different nitrogen grain fertilizer levels μg/g"

品种Variety 处理Treatment Fe Mn Zn Cu Ca P
扬稻6号 N1 12.86±0.12c 7.04±0.11c 11.73±0.02c 5.54±0.06c 127.41±0.76a 929.54±0.83a
Yangdao 6 N2 19.82±0.45b 7.35±0.07b 12.77±0.32b 6.29±0.03b 115.12±2.67b 907.60±2.10b
N3 29.48±0.15a 8.07±0.01a 16.01±0.02a 7.58±0.01a 105.98±0.62c 849.91±1.06c
南粳9108 N1 10.66±0.04c 9.34±0.04b 10.52±0.01c 4.97±0.02c 86.08±1.25a 983.87±0.30a
Nanjing 9108 N2 13.42±0.05b 9.51±0.07b 13.44±0.08b 5.29±0.04b 78.06±0.21b 969.48±7.54b
N3 20.99±0.09a 11.91±0.06a 14.43±0.03a 5.72±0.02a 74.89±1.27c 897.38±4.17c
F值Fvalue 品种Variety 2 359.38** 5 235.50** 82.13** 4 181.43** 145.50** 68.86**
氮素粒肥Nitrogen grain fertilizer 4 511.92** 870.11** 913.51** 2 104.00** 9.88* 58.82**
品种×氮素粒肥
Variety×Nitrogen grain fertilizer
248.52** 198.89** 79.06** 465.17** 0.96ns 0.40ns

Table 3

Varieties difference of RVA profile characteristics in polished rice under different nitrogen grain fertilizer levels"

品种
Variety
处理
Treatment
最高粘度(cp)
Peak viscosity
热浆粘度(cp)
Hot viscosity
崩解值(cp)
Breakdown
最终粘度(cp)
Final viscosity
回复值(cp)
Consistence
消减值(cp)
Setback
峰值时间(min)
Peak time
糊化温度(℃)
Pasting temperature
扬稻6号 N1 2 640±12.02a 1 855±5.66a 785±17.68a 3 129±0.71a 1 274±6.36b 489±11.31c 6.43±0.03c 73.17±0.03b
Yangdao 6 N2 2 515±11.31b 1 752±8.49b 763±19.80a 3 083±14.14b 1 331±5.66a 568±25.46b 6.53±0.03b 74.94±0.21a
N3 2 304±7.07c 1 619±0.71c 686±6.36b 2 963±1.41c 1 345±0.71a 659±5.66a 6.69±0.00a 75.00±0.13a
南粳9108 N1 3 167±1.41a 2 249±2.83a 918±4.24a 3 412±7.07a 1 163±9.90b 245±5.66c 6.35±0.07c 74.13±0.11b
Nanjing 9108 N2 3 012±1.42b 2 171±2.12b 842±3.54b 3 341±5.66b 1 171±3.54b 329±7.07b 6.49±0.01b 74.15±0.07b
N3 2 811±3.54c 2 028±7.78c 783±11.31c 3 229±2.12c 1 201±9.90a 418±1.41a 6.59±0.04a 75.65±0.07a
F值Fvalue 品种Variety 13 828.68** 16 811.97** 212.04** 4 506.91** 1 220.68** 1 175.28** 9.46* 16.75**
氮素粒肥
Nitrogen grain
fertilizer
2 144.96** 1 798.08** 91.71** 655.47** 64.09** 198.00** 26.26** 204.42**
品种×氮素粒肥
Variety×Nitrogen
grain fertilizer
4.31ns 5.16ns 5.18* 3.57ns 13.78** 0.04ns 0.23ns 65.95**

Fig.1

Changes of protein content and taste value in polished rice under different nitrogen grain fertilizer levels Different small letters indicate significant difference at 0.05 probability level between treatments under the same variety"

Table 4

Correlation analysis between protein content and different mineral elements in polished rice"

品种Variety Mg K Fe Mn Zn Cu Ca P
扬稻6号Yangdao 6 -0.988** -0.968** 0.946** 0.878* 0.859* 0.924** -0.874* -0.843*
南粳9108 Nanjing 9108 -0.989** -0.981** 0.938** 0.854* 0.970** 0.980** -0.967** -0.892*

Table 5

Correlation analysis between Mg/K, Mg/(N·AC·K) and characteristic values of RVA"

性状
Trait
Mg/K Mg/(N·AC·K)
扬稻6号Yangdao 6 南粳9108 Nanjing 9108 扬稻6号Yangdao 6 南粳9108 Nanjing 9108
食味值Taste value 0.909* 0.980** 0.986** 0.999**
最高粘度Peak viscosity 0.989** 0.999** 0.907* 0.986**
热浆粘度Hot viscosity 0.998** 0.991** 0.938** 0.968**
崩解值Breakdown 0.920** 0.988** 0.793 0.993**
最终粘度Final viscosity 0.983** 0.997** 0.857* 0.972**
回复值Consistence -0.897* -0.891* -0.996** -0.874*
消减值Setback -0.969** -0.996** -0.933** -0.995**
糊化温度Pasting temperature -0.821* -0.891* -0.964** -0.819*
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