Measurement of Off-Flavoring Volatile Compounds and Microbial Load as a Probable Marker for Keeping Quality of Pasteurized Milk
Abstract
:Featured Application
Abstract
1. Introduction
2. Materials and Methods
2.1. Samples and Storage Conditions
2.2. Microbiological Analysis
2.3. Extraction of Volatile Compounds and Solid Phase Micro Extraction
2.4. Identification and Quantification Volatile by GC-FID
2.5. Sensory Analysis
2.6. Statistical Analysis
3. Results and Discussion
3.1. Optimization of SPME Experimental Conditions
3.2. Quantification of Volatiles in Pasteurized Milk
3.3. Microbial Count and Spoilage Indication
3.4. Sensory Evaluation
3.5. Correlation between Sensory, Microbiological and Volatile Compounds
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Volatile Compounds | Storage Days | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
0 | 1 | 5 | 9 | 12 | 14 | 16 | 17 | 18 | 19 | |
Acetone | 75.6 ± 1.13 | 77.4 ± 2.65 | 78.7 ± 1.53 | 82.6 ± 2.08 | 79.5 ± 3.01 | 84.9 ± 1.27 | 85.6 ± 2.05 | 87.4 ± 1.14 | 93.2 ± 1.07 | 93.3 ± 2.14 |
Butanone | 8.06 ± 0 | 8.36 ± 0 | 8.68 ± 0.01 | 8.89 ± 1.04 | 9.09 ± 0 | 9.31 ± 1.02 | 9.42 ± 0.02 | 9.64 ± 2.06 | 9.86 ± 1.52 | 10.23 ± 2 |
Ethanol | 0.01 ± 0.01 | 0.16 ± 0.1 | 1.07 ± 0.4 | 1.23 ± 0.45 | 1.67 ± 0.66 | 1.52 ± 0.52 | 1.54 ± 1.03 | 1.77 ± 1.24 | 1.83 ± 1.48 | 1.99 ± 1 |
Pentanal | 1.21 ± 0.04 | 1.33 ± 0.06 | 1.89 ± 0.08 | 2.57 ± 0.92 | 3.15 ± 0.54 | 3.94 ± 0.73 | 4.82 ± 0.08 | 5.40 ± 0.65 | 6.15 ± 1.08 | 7.83 ± 1.14 |
1-Butanol | 0.02 ± 0 | 0.01 ± 0 | 0.01 ± 0 | 0.02 ± 0 | 0.03 ± 0.02 | 0.02 ± 0 | 0.03 ± 0.02 | 0.07 ± 0.01 | 0.13 ± 0.01 | 0.41 ± 0.02 |
3-Meth-1-Butanol | ND | ND | ND | ND | ND | ND | ND | ND | 0.02 ± 0.01 | 0.09 ± 0.01 |
Heptanal | 0.01 ± 0 | 0.02 ± 02 | 0.02 ± 0.02 | 0.03 ± 0.01 | 0.07 ± 0.04 | 0.06 ± 0.02 | 0.13 ± 0.05 | 0.27 ± 0.10 | 0.45 ± 0.13 | 0.957 ± 0 |
2,3-Butanediol | ND | ND | ND | ND | ND | ND | ND | ND | 0.016 ± 0 | 0.017 ± 0 |
1-Hexanol | ND | ND | ND | ND | ND | ND | ND | ND | 0.002 ± 0 | 0.002 ± 0 |
2-Eth-1-Hexanol | ND | ND | ND | ND | ND | ND | ND | ND | 0.002 ± 0 | 0.003 ± 0 |
1-Pentanol | ND | ND | 0.05 | ND | ND | ND | ND | 0.59 ± 0.13 | 0.84 ± 0.2 | 0.95 ± 0.01 |
Hexanone | ND | ND | ND | ND | ND | ND | ND | 0.065 ± 0 | 0.077 ± 0 | 0.088 ± 0 |
Volatile Compounds | Storage Days | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
0 | 1 | 5 | 9 | 12 | 14 | 16 | 17 | 18 | 19 | |
Acetaldehyde | ND | ND | ND | ND | ND | ND | ND | 4.53 ± 0.64 | 8.34 ± 0 | 16.3 ± 0.70 |
Acetone | 73.5 ± 1.12 | 74.3 ± 1.05 | 76.8 ± 2.03 | 85.5 ± 2.18 | 87.5 ± 3.01 | 88.7 ± 1.20 | 91.5 ± 2.05 | 93.6 ± 1.47 | 96.5 ± 2.05 | 99.6 ± 2.17 |
Butanone | 7.06 ± 0.02 | 8.07 ± 0.02 | 9.10 ± 0.02 | 9.12 ± 0.01 | 10.3 ± 0.02 | 10.9 ± 0.10 | 11.4 ± 0.01 | 10.2 ± 0.02 | 11.3 ± 0.4 | 12.9 ± 1.20 |
Ethanol | 0.03 ± 0. | 0.21 ± 0.2 | 0.57 ± 0.5 | 0.73 ± 0.45 | 0.97 ± 0.3 | 0.94 ± 0.02 | 1.64 ± 1.53 | 1.92 ± 0.01 | 2.11 ± 0.12 | 4.29 ± 0.12 |
Pentanal | 1.17 ± 0.03 | 1.58 ± 0.05 | 2.05 ± 0.09 | 2.87 ± 0.12 | 3.37 ± 0.64 | 3.94 ± 0.73 | 5.12 ± 0.25 | 6.56 ± 0.72 | 7.91 ± 0.14 | 9.02 ± 1.03 |
1-Butanol | 0.02 | 0.03 ± 0 | 0.08 ± 0 | 0.12 ± 0.02 | 0.13 ± 0.03 | 0.22 ± 0.06 | 0.25 ± 0.02 | 0.57 ± 0.01 | 0.73 ± 0.01 | 0.91 ± 0.02 |
Hexanal | ND | ND | ND | ND | ND | ND | ND | 0.012 ± 0 | 0.02 ± 0 | 0.05 ± 0.01 |
2-Meth-1-Pro-ol | ND | ND | ND | ND | ND | ND | ND | 0.000 | 0.06 ± 0.01 | 0.16 ± 0.05 |
Heptanal | 0.02 ± 0 | 0.01 ± 0.01 | 0.01 ± 0.02 | 0.04 ± 0.03 | 0.09 ± 0.05 | 0.12 ± 0.06 | 0.16 ± 0.05 | 0.36 ± 0.14 | 0.91 ± 0.11 | 1.64 ± 0.32 |
Octanal | ND | ND | ND | ND | ND | ND | ND | 0.000 | 0.02 ± 0 | 0.08 ± 0 |
3-Meth-1-Butanol | ND | ND | ND | ND | ND | ND | ND | 0.000 | 0.01 ± 0 | 0.06 ± 0.02 |
2,3-Butanediol | ND | ND | ND | ND | ND | ND | ND | 0.089 ± 0 | 0.09 ± 0.01 | 0.22 ± 0.04 |
2-Ethy-1-hexanol | ND | ND | ND | ND | ND | 0.001 ± 0 | 0.002 ± 0 | 0.002 ± 0 | 0.002 ± 0 | 0.01 ± 0 |
1-Pentanol | ND | ND | ND | ND | ND | 1.70 ± 0.76 | 0.96 ± 0.10 | 0.73 ± 0.46 | 0.63 ± 0.14 | 0.57 ± 0.77 |
Hexanon | ND | ND | ND | ND | ND | 0.065 ± 0 | 0.07 ± 0 | 0.09 ± 0.05 | 0.09 ± 0.02 | 0.06 ± 0.04 |
Volatile Compounds | Storage Days | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
0 | 1 | 5 | 9 | 12 | 14 | 16 | 17 | 18 | 19 | |
Acetaldehyde | ND | ND | ND | ND | ND | ND | 8.38 ± 3.02 | 8.62 ± 2.38 | 9.10 ± 0.83 | 9.99 ± 0.81 |
Acetone | 72.8 ± 1.32 | 74.8 ± 1.25 | 79.8 ± 2.33 | 88.6 ± 2.38 | 90.4 ± 2.41 | 92.7 ± 1.28 | 97.3 ± 2.65 | 101.6 ± 2.4 | 109.5 ± 3.5 | 139.6 ± 6.7 |
Butanal | ND | ND | ND | ND | ND | ND | ND | 0.31 ± 0.44 | 1.31 ± 0.59 | 1.63 ± 0.93 |
Butanone | 7.56 ± 0.03 | 8.17 ± 0.05 | 9.19 ± 0.05 | 9.56 ± 0.04 | 10.9 ± 0.10 | 12.1 ± 0.10 | 12.3 ± 0.01 | 13.7 ± 0.12 | 13.3 ± 0.6 | 15.4 ± 2.20 |
Ethanol | 0.04 ± 0.01 | 0.20 ± 0.02 | 0.87 ± 0.4 | 1.23 ± 0.85 | 1.43 ± 0.36 | 1.94 ± 0.12 | 2.34 ± 1.03 | 2.82 ± 0.06 | 3.71 ± 0.52 | 5.29 ± 1.17 |
Pentanal | 1.13 ± 0.02 | 1.47 ± 0.04 | 2.65 ± 0.19 | 3.78 ± 0.12 | 3.37 ± 0.64 | 3.96 ± 0.5 | 5.72 ± 0.45 | 7.36 ± 0.65 | 8.92 ± 0.84 | 11.2 ± 2.06 |
Propanol | ND | ND | ND | ND | ND | ND | 0.10 ± 0.02 | 0.14 ± 0.05 | 0.15 ± 0 | 0.16 ± 0 |
Eth-Butanol | ND | ND | ND | ND | ND | ND | ND | 0.013 ± | 0.013 ± 0 | 0.014 ± 0 |
Hexanal | ND | ND | ND | ND | ND | ND | 0.10 ± 0.01 | 0.10 ± 0 | 0.11 ± 0.01 | 0.12 ± 0.05 |
2-Meth-1-Pro-ol | ND | ND | ND | ND | ND | ND | 0.21 ± 0.13 | 0.54 ± 0.28 | 0.55 ± 0 | 0.56 ± 0.18 |
Heptanal | 0.02 | 0.04 ± 0 | 0.18 ± 0.01 | 0.21 ± 0.03 | 0.43 ± 0.05 | 0.63 ± 0.04 | 0.55 ± 0.02 | 0.78 ± 0.08 | 1.07 ± 0.29 | 1.51 ± 0.43 |
3Meth-1Butanol | ND | ND | ND | 0.011 ± 0 | 0.01 ± 0 | 0.01 ± 0 | 0.02 ± 0 | 0.04 ± 0.19 | 0.09 ± 0.08 | 0.23 ± 0.11 |
Trans-2-Hexenal | ND | ND | ND | 0.015 ± 0 | 0.015 ± 0 | 0.016 ± 0 | 0.02 ± 0 | 0.03 ± 0.01 | 0.05 ± 0.02 | 0.06 ± 0.02 |
Octanal | ND | ND | ND | ND | ND | ND | 0.67 ± 0.01 | 0.68 ± 0.04 | 0.69 ± 0.03 | 0.71 ± 0.02 |
2,3-Butanediol | ND | ND | ND | ND | ND | ND | ND | 0.27 ± 0.03 | 0.16 ± 0.2 | 0.07 ± 0.01 |
Hex- Propanone | ND | ND | ND | ND | ND | ND | ND | 0.07 ± 0 | 0.07 ± 0 | 0.06 ± 0 |
1-Hexanol | ND | ND | ND | ND | ND | ND | 0.002 ± 0 | 0.003 ± 0 | 0.003 ± 0 | 0.003 ± 0 |
1-Pentanol | ND | ND | ND | ND | ND | ND | 0.94 ± | 6.46 ± 1.68 | 23.73 ± 0.1 | 24.17 ± 0.1 |
Hexanon | ND | ND | ND | ND | ND | ND | 0.13 ± 0.02 | 0.12 ± 0.02 | 0.05 ± 0.01 | 0.04 ± 0 |
Storage Days | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Temp. | 0 | 1 | 5 | 9 | 12 | 14 | 16 | 17 | 18 | 19 | Mean | |
4 °C | 0.83 ± 0.14l | 0.83 ± 0.14l | 0.83 ± 0.15l | 0.96 ± 0.14l | 1.46 ± 0.07jkl | 1.75 ± 0.20h-k | 2.08 ± 0.07g-j | 2.16 ± 0.07ghi | 2.20 ± 0.12ghi | 2.33 ± 0.03gh | 1.54 ± 0.12C | |
TCC | 7 °C | 0.83 ± 0.14l | 0.83 ± 0.14l | 0.83 ± 0.14l | 1.29 ± 0.10kl | 1.79 ± 0.05h-k | 2.30 ± 0.06ghi | 2.56 ± 0.05fg | 3.04 ± 0.03ef | 3.63 ± 0.17de | 4.08 ± 0.05cd | 2.12 ± 0.21B |
10 °C | 0.83 ± 0.14l | 0.83 ± 0.13l | 0.96 ± 0.16l | 1.64 ± 0.09ijk | 2.47 ± 0.20fg | 3.56 ± 0.22de | 4.17 ± 0.01cd | 4.53 ± 0.01bc | 4.96 ± 0.01ab | 5.36 ± 0.17a | 2.93 ± 0.32A | |
Mean | 0.83 ± 0.07G | 0.83 ± 0.07G | 0.87 ± 0.08G | 1.30 ± 0.11F | 1.91 ± 0.16E | 2.54 ± 0.28D | 2.94 ± 0.32C | 3.24 ± 0.35C | 3.60 ± 0.40B | 3.93 ± 0.44A | ||
4 °C | 3.14 ± 0.03n | 3.14 ± 0.03n | 3.17 ± 0.04n | 3.27 ± 0.06n | 3.72 ± 0.04mn | 4.41 ± 0.21lm | 5.46 ± 0.24jk | 6.92 ± 0.16gh | 7.14 ± 0.10gh | 7.90 ± 0.11g | 4.83 ± 0.33C | |
SPC | 7 °C | 3.14 ± 0.02n | 3.14 ± 0.07n | 3.22 ± 0.06n | 3.64 ± 0.03n | 4.80 ± 0.15ijk | 5.77 ± 0.12ij | 7.74 ± 0.17g | 9.87 ± 0.11f | 11.64 ± 0.31de | 12.13 ± 0.19d | 6.51 ± 0.63B |
10 °C | 3.14 ± 0.02n | 3.16 ± 0.02n | 3.38 ± 0.05n | 4.55 ± 0.05lm | 6.65 ± 0.hi33 | 10.86 ± 0.2e0 | 12.67 ± 0.24c | 14.23 ± 0.34b | 15.54 ± 0.40a | 14.33 ± 0.31b | 8.85 ± 0.91A | |
Mean | 3.14 ± 0.01G | 3.15 ± 0.02G | 3.25 ± 0.04G | 3.82 ± 0.19F | 5.06 ± 0.44E | 7.01 ± 0.99D | 8.62 ± 1.07C | 10.34 ± 1.07B | 11.44 ± 1.22A | 11.45 ± 0.95A | ||
4 °C | 2.24 ± 0.02o | 2.26 ± 0.03o | 2.61 ± 0.04o | 3.34 ± 0.03ij | 4.74 ± 0.02g | 5.86 ± 0.04e | 6.93 ± 0.05d | 7.76 ± 0.09c | 9.13 ± 0.10b | 11.67 ± 0.30a | 5.65 ± 0.57A | |
TPC | 7 °C | 2.24 ± 0.03o | 2.23 ± 0.01o | 2.32 ± 0.00o | 2.68 ± 0.05no | 2.86 ± 0.05klm | 3.44 ± 0.03i | 4.12 ± 0.05h | 4.95 ± 0.06fg | 5.27 ± 0.06f | 6.20 ± 0.12e | 3.63 ± 0.25B |
10 °C | 2.24 ± 0.02o | 2.25 ± 0.01o | 2.25 ± 0.03o | 2.29 ± 0.05no | 2.53 ± 0.05mn | 2.75 ± 0.03lm | 2.97 ± 0.06jkl | 3.22 ± 0.05ijk | 3.50 ± 0.01i | 3.99 ± 0.06h | 2.80 ± 0.11C | |
Mean | 2.24 ± 0.01H | 2.25 ± 0.01H | 2.39 ± 0.06H | 2.77 ± 0.16G | 3.38 ± 0.34F | 4.02 ± 0.47E | 4.67 ± 0.59D | 5.31 ± 0.66C | 5.96 ± 0.83B | 7.29 ± 1.14A |
Parameter | Temp. | Storage Days | Mean | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1 | 5 | 9 | 12 | 14 | 16 | 17 | 18 | 19 | |||
4 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.33 ± 0.33 | 8.00 ± 0.58 | 7.17 ± 0.60 | 7.00 ± 0.00 | 6.83 ± 0.17 | 6.33 ± 0.17 | 5.67 ± 0.44 | 7.63 ± 0.23A | |
Aroma | 7 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.33 ± 0.33 | 7.67 ± 0.17 | 6.67 ± 0.33 | 6.33 ± 0.17 | 6.33 ± 0.17 | 5.83 ± 0.17 | 5.17 ± 0.17 | 7.33 ± 0.26B |
10 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.33 ± 0.33 | 8.00 ± 0.58 | 7.00 ± 0.58 | 6.33 ± 0.17 | 6.17 ± 0.17 | 6.17 ± 0.17 | 5.67 ± 0.17 | 4.33 ± 0.17 | 7.00 ± 0.28C | |
Mean | 9.00 ± 0.00A | 9.00 ± 0.00A | 8.78 ± 0.15AB | 8.22 ± 0.22BC | 7.56 ± 0.28C | 6.72 ± 0.24D | 6.50 ± 0.14DE | 6.44 ± 0.13DE | 5.94 ± 0.13E | 5.06 ± 0.24F | ||
4 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.00 ± 0.50 | 8.00 ± 0.00 | 7.50 ± 0.00 | 7.00 ± 0.29 | 7.00 ± 0.58 | 6.50 ± 0.29 | 6.00 ± 0.29 | 7.70 ± 0.21A | |
Taste | 7 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.50 ± 0.00 | 8.33 ± 0.17 | 7.67 ± 0.33 | 7.00 ± 0.00 | 6.33 ± 0.33 | 6.00 ± 0.00 | 6.00 ± 0.29 | 5.00 ± 0.00 | 7.28 ± 0.25B |
10 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.00 ± 0.29 | 7.33 ± 0.33 | 7.00 ± 0.58 | 6.67 ± 0.33 | 5.50 ± 0.50 | 5.67 ± 0.33 | 5.00 ± 0.29 | 4.00 ± 0.06 | 6.72 ± 0.31C | |
Mean | 9.00 ± 0.00A | 9.00 ± 0.00A | 8.50 ± 0.17AB | 7.89 ± 0.23BC | 7.56 ± 0.24CD | 7.06 ± 0.15D | 6.28 ± 0.29E | 6.22 ± 0.28E | 5.83 ± 0.26E | 5.00 ± 0.30F | ||
4 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.33 ± 0.17 | 8.00 ± 0.29 | 7.50 ± 0.29 | 7.33 ± 0.33 | 7.00 ± 0.58 | 6.00 ± 0.00 | 8.02 ± 0.20A | |
OAA | 7 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.50 ± 0.00 | 8.50 ± 0.29 | 7.83 ± 0.17 | 7.50 ± 0.00 | 7.00 ± 0.58 | 6.83 ± 0.44 | 6.17 ± 0.33 | 5.17 ± 0.17 | 7.55 ± 0.24B |
10 °C | 9.00 ± 0.00 | 9.00 ± 0.00 | 8.00 ± 0.58 | 8.17 ± 0.17 | 7.50 ± 0.29 | 7.00 ± 0.29 | 6.00 ± 0.58 | 5.83 ± 0.17 | 5.67 ± 0.17 | 4.02 ± 0.04 | 7.02 ± 0.30C | |
Mean | 9.00 ± 0.00A | 9.00 ± 0.00A | 8.50 ± 0.22AB | 8.56 ± 0.15AB | 7.89 ± 0.16BC | 7.50 ± 0.19CD | 6.83 ± 0.33DE | 6.67 ± 0.28E | 6.28 ± 0.28E | 5.06 ± 0.29F |
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Rashid, A.; Javed, I.; Rasco, B.; Sablani, S.; Ayaz, M.; Ali, M.A.; Abdullah, M.; Imran, M.; Gondal, T.A.; Afzal, M.I.; et al. Measurement of Off-Flavoring Volatile Compounds and Microbial Load as a Probable Marker for Keeping Quality of Pasteurized Milk. Appl. Sci. 2019, 9, 959. https://doi.org/10.3390/app9050959
Rashid A, Javed I, Rasco B, Sablani S, Ayaz M, Ali MA, Abdullah M, Imran M, Gondal TA, Afzal MI, et al. Measurement of Off-Flavoring Volatile Compounds and Microbial Load as a Probable Marker for Keeping Quality of Pasteurized Milk. Applied Sciences. 2019; 9(5):959. https://doi.org/10.3390/app9050959
Chicago/Turabian StyleRashid, Anjum, Imran Javed, Barbara Rasco, Shyam Sablani, Muhammad Ayaz, Muhammad A. Ali, Muhammad Abdullah, Muhammad Imran, Tanweer Aslam Gondal, Muhammad Inam Afzal, and et al. 2019. "Measurement of Off-Flavoring Volatile Compounds and Microbial Load as a Probable Marker for Keeping Quality of Pasteurized Milk" Applied Sciences 9, no. 5: 959. https://doi.org/10.3390/app9050959
APA StyleRashid, A., Javed, I., Rasco, B., Sablani, S., Ayaz, M., Ali, M. A., Abdullah, M., Imran, M., Gondal, T. A., Afzal, M. I., Atif, M., Salehi, B., Rodrigues, C. F., Sharifi-Rad, J., & Martins, N. (2019). Measurement of Off-Flavoring Volatile Compounds and Microbial Load as a Probable Marker for Keeping Quality of Pasteurized Milk. Applied Sciences, 9(5), 959. https://doi.org/10.3390/app9050959