Bulk and Surface Chemical Composition of Wheat Flour Particles of Different Sizes

Table 4

The functional group content of C, O, N, P, and S on the surface chemical composition of flour particles of different sizes (%).

Binding energy (eV)	Element		Functional group	#1	#2	#3	#4	#5	#6	#7	#8	SD
285.2	C1s			71.50	73.25	72.58	72.97	74.14	71.77	72.17	71.80	0.89
284.6		Peak 1	C-C, C-H	49.55	49.37	49.31	47.48	46.70	46.77	47.46	49.26	1.25
286.5		Peak 2	C-O, C-N, O-C-O, O=C-O, O=C-N	19.23	20.93	21.48	23.82	27.98	25.4	23.49	20.69	2.87
287.9		Peak 3	O=C-OH, O=C-OR	3.36	3.24	3.09	3.07	2.95	3.17	3.58	3.90	0.31
532.3	O1s			22.63	21.31	21.27	21.17	20.08	22.03	21.63	22.06	0.77
531.4		Peak 1	O=C-OH, O=C-N, O=C-O	6.62	6.29	6.59	5.80	4.91	5.78	6.06	6.07	0.55
532.6		Peak 2	C-OH, C-O-C	8.77	8.38	8.39	8.39	6.82	7.65	7.59	7.99	0.62
533.3		Peak 3	O=C-OH	6.23	5.65	5.55	6.11	5.12	5.40	5.75	5.57	0.36
399.9	N1s			5.36	4.89	5.53	5.20	5.10	5.47	5.45	5.39	0.22
399.8		Peak 1	O=C-NH, O=C-NH2	2.63	2.52	2.34	2.24	2.43	2.73	2.78	2.99	0.25
401.9		Peak 2	C-NH3^+	2.97	2.94	2.45	2.27	2.20	2.22	2.51	2.68	0.31
133.3	P2p			0.22	0.27	0.31	0.35	0.37	0.37	0.42	0.38	0.07
133.1				0.26	0.32	0.40	0.45	0.43	0.45	0.43	0.44	0.07
164.0	S2p			0.29	0.30	0.32	0.31	0.32	0.36	0.34	0.37	0.03
163.6				0.35	0.36	0.40	0.39	0.36	0.43	0.35	0.43	0.03