Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product
This study investigated the effect of fermentation conditions (time and temperature) on the nutritional composition and health-promoting properties of raw milk, optimized naturally fermented <i>amasi</i>, and <i>amasi</i> fermented with starter culture. The composition of the...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | Fermentation |
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| Online Access: | https://www.mdpi.com/2311-5637/8/10/493 |
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| author | Mpho Sebabiki Maleke Oluwafemi Ayodeji Adebo |
| author_facet | Mpho Sebabiki Maleke Oluwafemi Ayodeji Adebo |
| author_sort | Mpho Sebabiki Maleke |
| collection | DOAJ |
| description | This study investigated the effect of fermentation conditions (time and temperature) on the nutritional composition and health-promoting properties of raw milk, optimized naturally fermented <i>amasi</i>, and <i>amasi</i> fermented with starter culture. The composition of the products, including chemical analysis, amino acids, mineral composition, and fatty acids, as well as health-promoting properties (total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity assays (2,2-Azinobis (3-Ethyl-Benzothiazone-6-Sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) were investigated. The results showed that the fermentation conditions (time and temperature) significantly affected the ash contents of both fermented samples. Fermentation was also observed to have increased the contents of most of the essential and non-essential amino acids. A high concentration of glutamic acid was observed in optimized naturally fermented <i>amasi</i> at 32 °C (OP32, 6.30 g/100 g), followed by starter-culture-fermented <i>amasi</i> at 25 °C (SC25, 5.58 g/100 g) and then starter-culture-fermented <i>amasi</i> at 32 °C (SC32, 5.35 g/100 g), with optimized naturally fermented <i>amasi</i> at 32 °C (OP25, 4.46 g/100 g) having the lowest concentration. A similar trend in the composition of minerals was also observed, with potassium being the most abundant (110.1–134.5 µg/g). The TPC, TFC, and the antioxidant activities were significantly improved by fermentation, while a significant reduction in free fatty acids was recorded. In conclusion, the fermentation conditions had a significant effect on the nutritional and health-promoting properties of <i>amasi</i>. The results provided in this study could provide nutritional information regarding the composition of <i>amasi</i>, which can be beneficial to produce a high-quality product. |
| first_indexed | 2024-03-09T12:20:12Z |
| format | Article |
| id | doaj.art-ce2e1060ad55414eba52cd2206520fc2 |
| institution | Directory Open Access Journal |
| issn | 2311-5637 |
| language | English |
| last_indexed | 2024-03-09T12:20:12Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fermentation |
| spelling | doaj.art-ce2e1060ad55414eba52cd2206520fc22023-11-30T22:41:55ZengMDPI AGFermentation2311-56372022-09-0181049310.3390/fermentation8100493Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk ProductMpho Sebabiki Maleke0Oluwafemi Ayodeji Adebo1Department of Biotechnology and Food Technology, Faculty of Science, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South AfricaDepartment of Biotechnology and Food Technology, Faculty of Science, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South AfricaThis study investigated the effect of fermentation conditions (time and temperature) on the nutritional composition and health-promoting properties of raw milk, optimized naturally fermented <i>amasi</i>, and <i>amasi</i> fermented with starter culture. The composition of the products, including chemical analysis, amino acids, mineral composition, and fatty acids, as well as health-promoting properties (total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity assays (2,2-Azinobis (3-Ethyl-Benzothiazone-6-Sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) were investigated. The results showed that the fermentation conditions (time and temperature) significantly affected the ash contents of both fermented samples. Fermentation was also observed to have increased the contents of most of the essential and non-essential amino acids. A high concentration of glutamic acid was observed in optimized naturally fermented <i>amasi</i> at 32 °C (OP32, 6.30 g/100 g), followed by starter-culture-fermented <i>amasi</i> at 25 °C (SC25, 5.58 g/100 g) and then starter-culture-fermented <i>amasi</i> at 32 °C (SC32, 5.35 g/100 g), with optimized naturally fermented <i>amasi</i> at 32 °C (OP25, 4.46 g/100 g) having the lowest concentration. A similar trend in the composition of minerals was also observed, with potassium being the most abundant (110.1–134.5 µg/g). The TPC, TFC, and the antioxidant activities were significantly improved by fermentation, while a significant reduction in free fatty acids was recorded. In conclusion, the fermentation conditions had a significant effect on the nutritional and health-promoting properties of <i>amasi</i>. The results provided in this study could provide nutritional information regarding the composition of <i>amasi</i>, which can be beneficial to produce a high-quality product.https://www.mdpi.com/2311-5637/8/10/493fermentationhealth-promoting propertiesnutritional compositionphytochemicalsfermented milk |
| spellingShingle | Mpho Sebabiki Maleke Oluwafemi Ayodeji Adebo Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product Fermentation fermentation health-promoting properties nutritional composition phytochemicals fermented milk |
| title | Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product |
| title_full | Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product |
| title_fullStr | Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product |
| title_full_unstemmed | Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product |
| title_short | Nutritional Composition and Health-Promoting Properties of <i>Amasi</i>: A South African Fermented Milk Product |
| title_sort | nutritional composition and health promoting properties of i amasi i a south african fermented milk product |
| topic | fermentation health-promoting properties nutritional composition phytochemicals fermented milk |
| url | https://www.mdpi.com/2311-5637/8/10/493 |
| work_keys_str_mv | AT mphosebabikimaleke nutritionalcompositionandhealthpromotingpropertiesofiamasiiasouthafricanfermentedmilkproduct AT oluwafemiayodejiadebo nutritionalcompositionandhealthpromotingpropertiesofiamasiiasouthafricanfermentedmilkproduct |