- FA3, which contained a high dose of multiple additives, was the most effective at improving aerobic stability of low-moisture crimped wheat grains. - All methods used to evaluate aerobic stability, including temperature rise, CO2 production, and visual appearance, provided useful information but visual appearance ranked the additives slightly differently than the other methods. - There were clear differences between additive treatments in terms of fermentation quality, microbial composition, and aerobic stability of dry crimped wheat grain ensiled, with FA3 performing the best.

1. Conclusions
• There were clear differences in the efficacy of additives in improving the aerobic stability of relatively low moisture crimped wheat
grains, with FA3 (high dose of additive including several ingredients) being the most efficient
• All methods used to evaluate aerobic stability provided useful information of the efficacy of the additives
• The correlation between temperature and CO2 production was very high indicating that CO2 produced by aerobic bacteria can be used
as a method to evaluate aerobic stability, while visual appearance ranked the additives slightly differently
Materials and Methods
• Crimped wheat grain: 270 g/kg MC
• Eight additive treatments:
1. Control (C) without additive
2. FA1 (80% formic acid [FA]; 5 l t-1)
3. FA2 (58% FA, 20% propionic acid [PA], 2.5% potassium
sorbate, 5.2% sodium formate [SF]; 5 l t-1)
4. FA3 (FA2 at 7 l t-1)
5. FA4 (76% FA, 5.5% SF; 7 l t-1)
6. FA5 (37% FA, 22% SF, 18% PA, 7.3% sodium, 1% sorbic acid;
5 l t-1)
7. PA1 (54% PA; 5 l t-1)
8. PA2 (37% PA, 14% sodium benzoate, 10% FA, 11% sodium
propionate; 4 l t-1)
• Three replicates per treatment
• Glass jars were opened after 57 days of ensiling: fermentation
quality and microbial quality
Aerobic stability:
1. Temperature rise
2. 50 g of sample was put into 0.5 l glass bottles: headspace gas
was sampled once daily and analysed for CO2 using a gas
chromatograph
3. Visual appearance of mould in the glass bottles once a day
using a score scale: 0 = no mould; 1 = slight mouldiness; 2 =
moderate mouldiness; and 3 = severe mouldiness
Introduction
• Crimped grain preservation is based on lactic acid fermentation
by anaerobic lactic acid bacteria
• Recommended grain moisture content (MC) is 300 – 400 g/kg
• In crimped grain with MC between 200 and 300 g/kg,
fermentation is restricted so that efficient protection is needed
against aerobic deteriorating organisms
Aerobic stability of crimped wheat grain
manipulated by additive treatments
detected using different methods
XVIII International Silage Conference, 24-26 July 2018, Bonn, Germany
M. Franco, T. Stefanski, T. Jalava, K. Kuoppala, A. Huuskonen, M. Rinne
Natural Resources Institute Finland (Luke), Finland
Correspondence: marcia.franco@luke.fi
Objective: to evaluate the fermentation quality, microbial
composition and aerobic stability of dryer than optimal crimped
wheat grain ensiled with different additives and to compare three
methods in evaluating the aerobic stability: 1) increase in
temperature, 2) measurement of CO2 produced by aerobic
bacteria 3) visual appearance of mould
Results
Figure 1 Aerobic stability of crimped wheat grain according to additive treatments.
*Treatment did not reach the threshold during the evaluation period.
Figure 4 Water soluble carbohydrate and pH of crimped wheat grain according to additive
treatments.
Table 1 Microbial composition of crimped wheat grain according to additive treatments.
Figure 2 Correlation between increase in temperature and the alternative methods to
evaluate aerobic stability.
Figure 3 Ammonia-N and ethanol of crimped wheat grain according to additive treatments.
y = 0.9523x - 16.962
R² = 0.936
y = 0.951x + 1.4331
R² = 0.979
y = 0.8036x + 20.791
R² = 0.567
y = 0.6664x + 47.619
R² = 0.528
48
72
96
120
144
168
192
48 72 96 120 144 168 192
Aerobicstability,hours
Aerobic stability, hours
CO2 threshold 1mg
CO2 threshold 2mg
Score threshold Score 1
Score threshold Score 2
a
a
b
b,*
ab
ab
b
a
0
24
48
72
96
120
144
168
192
C FA1 FA2 FA3 FA4 FA5 PA1 PA2
Aerobicstability,hours
a
a a a
a
a
b
a
d
a a a a
a
b
c
0
1
2
3
4
5
6
7
8
0
2
4
6
8
10
12
14
16
18
C FA1 FA2 FA3 FA4 FA5 PA1 PA2
Ethanol,g/kgDM(dots)
Amm-N,g/kgN(bars)
a
bc
c
bc
bc
ab ab
ab
e
b
c
a
bc
d d
d
4
5
6
7
15
20
25
30
35
40
45
C FA1 FA2 FA3 FA4 FA5 PA1 PA2
pH(dots)
Watersolublecarbohydrate,
g/kgDM(bars)
Photo: ©Luke / Marcia Franco
C FA1 FA2 FA3 FA4 FA5 PA1 PA2
Yeasts, CFU/g 2.7×103
<1×101
<1×101
<1×101
<1×101
1.5×103
4.2×103
4.1×104
Moulds, CFU/g 9×102
4.3×105
1.2×105
1.7×102
3.7×105
6.1×104
7.2×105
5.5×104
Photos: ©Luke / Taina Jalava