Using vibrational infrared biomolecular spectroscopy to detect heat-induced changes of molecular structure in relation to nutrient availability of prairie whole oat grains on a molecular basis

Table 2 Molecular structure spectral characteristics using ATR-FT/IR molecular spectroscopy: comparison among raw (RO), dry roasted (DO) and microwave irradiation (MIO) oat seed

Item	Oat Heat Treatment					Contrast
Item	Raw (RO)	Dry roasting (DO)	Microwave irradiation (MIO)	SEM	P value	Do vs MIO P value	MIO vs RO P value	DO vs RO P value
Protein amide molecular structure spectral profiles (Unit: Absorbance)
Amide I area	2.82	2.68	1.94	0.30	0.13	0.11	0.06	0.06
Amide II area	0.74	0.71	0.56	0.07	0.15	0.07	0.14	0.13
Ratio amide I to amide II area	3.94^a	3.61^ab	3.44^b	0.11	0.03	0.29	<0.01	<0.01
Amide I height	0.05	0.05	0.03	0.01	0.06	0.05	0.03	0.03
Amide II height	0.02^a	0.02^ab	0.01^b	<0.01	0.03	0.02	0.01	0.01
Ratio amide I to amide II height	2.47	2.45	2.55	0.05	0.36	0.18	0.28	0.28
Protein secondary structure spectral profile
a-helix (height)	0.05	0.04	0.03	0.01	0.06	0.11	0.02	0.02
β-sheet (height)	0.04^a	0.03^ab	0.02^b	0.004	0.03	0.12	<0.01	<0.01
Ratio a-helix to β-sheet	1.26^b	1.39^ab	1.40^a	0.01	<.0001	0.57	<.0001	<.0001
Starch related molecular structure spectral profiles
Starch area	7.50	7.92	6.86	0.78	0.643	0.35	0.71	0.57
Starch height	0.18	0.18	0.17	0.02	0.50	0.28	0.88	0.35
Ratio amide I to starch area	0.37^a	0.34^b	0.28^c	0.02	<0.01	0.02	<0.01	<0.01

ISSN: 2049-1891