Diagram 1.

Diagram 2.

Figure 1.

Basic chemical composition of A1 and A2 fermented milks (g/100 g; x ±SD, n=4)
| Component | β-CN variant in milk | |
|---|---|---|
| A1 | A2 | |
| TS | 11.00a ± 0.28 | 11.12a ± 0.26 |
| MSNF | 9.13a ± 0.20 | 9.23a ± 0.19 |
| Protein | 3.63a ± 0.28 | 3.66a ± 0.20 |
| Fat | 1.87a ± 0.13 | 1.89a ± 0.16 |
| Ash | 0.8002a ± 0.0081 | 0.7910a ± 0.0233 |
| Carbohydrates | 4.68a ± 0.25* | 4.80a ± 0.23* |
Microbiological characteristics of the analysed fermented milks (x ±SD, n=4)
| Count of starter microorganism [log CFU/g] | Storage time [week] | Genetic variant of β-CN | |
|---|---|---|---|
| A1A1 | A2A2 | ||
| ABT-yoghurt | |||
| Lb. acidophilus LA-5 | 0 | 8.47a ± 0.04 | 8.39a ± 0.07 |
| 3 | 8.20a ± 0.01 | 8.42a ± 0.15 | |
| Bifidobacterium BB-12 | 0 | 6.42a ± 0.66 | 6.65a ± 0.95 |
| 3 | 5.48a ± 0.54 | 5.45a ± 0.85 | |
| Str. thermophilus | 0 | 9.16a ± 0.74 | 9.13a ± 0.81 |
| 3 | 8.51a ± 0.14 | 8.52a ± 0.02 | |
| Kefir | |||
| Lactobacillus spp. | 0 | 9.16a ± 0.69 | 8.93a ± 0.88 |
| 3 | 6.76b ± 0.31 | 6.73b ± 1.03 | |
| Lactococcus spp. | 0 | 9.16a ± 0.04 | 9.19a ± 0.05 |
| 3 | 8.20b ± 0.40 | 8.01b ± 0.30 | |
| Yeasts | 0 | 2.99a ± 0.65 | 3.13a ± 0.57 |
| 3 | 4.33a ± 0.22 | 3.59a ± 1.28 | |
| Cultured milk | |||
| Lactococcus spp. | 0 | 8.98a ± 0.37 | 8.92a ± 0.19 |
| 3 | 7.45b ± 0.05 | 7.44b ± 0.16 | |
Textural and rheological characteristics of the analysed fresh (0w) and stored (3w) fermented milks (x ±SD, n=4)
| Attribute | ABT-yoghurt | Kefir | Cultured milk | ||||
|---|---|---|---|---|---|---|---|
| 0w | 3w | 0w | 3w | 0w | 3w | ||
| Hardness (N) | A1 | 0.85a ± 0.09 | 1.13b ± 0.16 | 0.39a ± 0.01 | 0.49bc ± 0.04 | 0.45a ± 0.02 | 0.50ab ± 0.01 |
| A2 | 0.97a ± 0.07 | 1.28b ± 0.04 | 0.46b ± 0.04 | 0.54c ± 0.07 | 0.51b ± 0.02 | 0.59c ± 0.06 | |
| Adhesiveness (|N×s|) | A1 | 1.52a ± 0.19 | 2.41a ± 0.37 | 0.63a ± 0.05 | 0.89a ± 0.17 | 0.74a ± 0.14 | 1.08b ± 0.09 |
| A2 | 2.25a ± 0.62 | 1.63a ± 0.93 | 0.92a ± 0.29 | 1.39b ± 0.38 | 1.12b ± 0.24 | 1.21b ± 0.31 | |
| Cohesiveness (−) | A1 | 0.44c ± 0.01 | 0.38a ± 0.01 | 0.48a ± 0.01 | 0.46a ± 0.04 | 0.50a ± 0.00 | 0.48a ± 0.01 |
| A2 | 0.41b ± 0.01 | 0.37a ± 0.03 | 0.50a ± 0.02 | 0.47a ± 0.02 | 0.43a ± 0.12 | 0.51a ± 0.01 | |
| Gumminess (N) | A1 | 0.37a ± 0.04 | 0.43ab ± 0.05 | 0.19a ± 0.00 | 0.22ab ± 0.01 | 0.22ab ± 0.01 | 0.22a ± 0.01 |
| A2 | 0.40a ± 0.03 | 0.47b ± 0.02 | 0.23b ± 0.01 | 0.26c ± 0.04 | 0.26b ± 0.02 | 0.29c ± 0.02 | |
| Hysteresis loop area (kPa · s−1) | A1 | 4.63a ± 0.25 | 4.73a ± 0.31 | 1.46a ± 0.10 | 1.50a ± 0.09 | 1.70a ± 0.07 | 1.71a ± 0.06 |
| A2 | 8.54b ± 0.09 | 8.61b ± 0.35 | 1.93b ± 0.09 | 1.78b ± 0.16 | 1.91b ± 0.04 | 2.10c ± 0.17 | |
| k (Pa sn) | A1 | 2.89a ± 0.26 | 4.17b ± 0.40 | 1.55a ± 0.40 | 5.19b ± 0.74 | 6.73a ± 0.24 | 6.58a ± 0.35 |
| A2 | 7.90c ± 0.65 | 12.23d ± 0.90 | 4.42b ± 0.35 | 4.92b± 0.73 | 7.29a ± 0.71 | 7.27a ± 0.67 | |
| n | A1 | 0.40c ± 0.01 | 0.24b ± 0.01 | 0.37c ± 0.02 | 0.29b ± 0.05 | 0.25a ± 0.01 | 0.27a ± 0.01 |
| A2 | 0.26b ± 0.03 | 0.16a ± 0.02 | 0.23a ± 0.01 | 0.32b ± 0.01 | 0.24a ± 0.03 | 0.26a ± 0.04 | |
| Initial η (Pas) | A1 | 4.90a ± 0.28 | 4.79a ± 0.06 | 1.71a ± 0.11 | 2.32b ± 0.38 | 2.48a ± 0.11 | 2.71a ± 0.22 |
| A2 | 6.07b ± 0.21 | 6.88c ± 0.46 | 2.17ab± 0.18 | 2.57b ± 0.25 | 2.82a ± 0.14 | 2.87a ± 0.26 | |
| Final η (Pas) | A1 | 0.21b ± 0.01 | 0.15a ± 0.00 | 0.14a ± 0.01 | 0.16a ± 0.03 | 0.16a ± 0.00 | 0.19b ± 0.01 |
| A2 | 0.24c ± 0.02 | 0.18ab ± 0.01 | 0.16a ± 0.01 | 0.17a ± 0.01 | 0.18b ± 0.01 | 0.21c ± 0.00 | |
| τ0 (Pa) | A1 | 23.13a ± 1.11 | 25.74b ± 1.00 | 12.68a ± 1.31 | 12.81a ± 1.55 | 11.26a ± 1.75 | 13.29a ± 0.97 |
| A2 | 29.67c ± 1.16 | 29.28c ± 1.01 | 10.96a ± 1.30 | 11.92a± 0.99 | 18.03b± 1.03 | 17.11b ± 0.59 | |
Acidity and antioxidant characteristics of the fresh (0w) and stored (3w) A1 and A2 fermented milks (x ±SD, n=4)
| Characteristic | ABT-yoghurt | Kefir | Cultured milk | ||||
|---|---|---|---|---|---|---|---|
| 0w | 3w | 0w | 3w | 0w | 3w | ||
| pH | A1 | 4.75b ± 0.15 | 4.41a ± 0.09 | 4.58a ± 0.03 | 4.54a ± 0.03 | 4.49a ± 0.01 | 4.47a ± 0.04 |
| A2 | 4.72b ± 0.08 | 4.40a ± 0.08 | 4.58a ± 0.03 | 4.54a ± 0.04 | 4.50a ± 0.02 | 4.45a ± 0.03 | |
| acidity (% lactic acid) | A1 | 0.70a ± 0.06 | 0.83b ± 0.03 | 0.92a ± 0.03 | 0.89a ± 0.02 | 0.98a ± 0.03 | 0.95a ± 0.03 |
| A2 | 0.70a ± 0.03 | 0.81b ± 0.05 | 0.90a ± 0.02 | 0.90a ± 0.01 | 0.94a ± 0.03 | 0.96a ± 0.02 | |
| FRAP (mMFe2+/kg) | A1 | 0.97a± 0.36 | 0.83a ± 0.11 | 0.72a ± 0.01 | 0.74a ± 0.03 | 0.92a ± 0.10 | 0.88a ± 0.22 |
| A2 | 0.96a ± 0.28 | 0.76a ± 0.05 | 0.67a ± 0.09 | 0.66a ± 0.08 | 0.87a ± 0.12 | 0.81a ± 0.10 | |
| ARP (mMTE/kg) | A1 | 0.32a ± 0.27 | 0.25a ± 0.09 | 0.23a ± 0.19 | 0.26a ± 0.13 | 0.29a ± 0.25 | 0.29a ± 0.14 |
| A2 | 0.29a ± 0.16 | 0.30a ± 0.15 | 0.23a ± 0.16 | 0.27a ± 0.11 | 0.31a ± 0.26 | 0.31a ± 0.17 | |
Sensory properties of A1 and A2 fermented milks (x ±SD, n=14)
| Sensory characteristic | ABT-yoghurt | Kefir | Cultured milk | |||
|---|---|---|---|---|---|---|
| A1 | A2 | A1 | A2 | A1 | A2 | |
| Colour | 4.82a ± 0.37 | 4.82a ± 0.54 | 4.93a ± 0.27 | 4.93a ± 0.27 | 4.86a ± 0.36 | 5.00a ± 0.00 |
| Appearance | 3.64a ± 0.66 | 3.29a ± 0.75 | 4.32a ± 0.42 | 4.29a ± 0.80 | 4.00a ± 0.55 | 4.61b ± 0.59 |
| Consistency | 4.43a ± 0.58 | 4.29a ± 0.67 | 4.89b ± 0.29 | 4.39a ± 0.71 | 4.32a ± 0.64 | 4.86b ± 0.53 |
| Odour | 4.57a ± 0.42 | 4.54a ± 0.37 | 4.89a ± 0.29 | 4.61a ± 0.49 | 4.54a ± 0.66 | 4.57a ± 0.51 |
| Taste | 4.46a ± 0.57 | 4.29a ± 0.58 | 4.50a ± 0.48 | 4.64a ± 0.57 | 4.50a ± 0.73 | 4.71a ± 0.38 |
| Total score | 4.38a ± 0.35 | 4.23a ± 0.41 | 4.67a ± 0.26 | 4.55a ± 0.43 | 4.42a ± 0.50 | 4.74b ± 0.21 |