| 1. |
- Vilanculos, Serafina, 1961, et al.
(författare)
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Degradation of phytate in composite wheat/cassava/sorghum bread by activation of intrinsic cereal phytase
- 2021
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Ingår i: African Journal of Food Science. - 1996-0794. ; 15:1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to degrade the phytic acid content in composite wheat/cassava/ sorghum bread by activating intrinsic cereal phytases during the baking process. The aim was to reach a phytate:iron molar ratio <1 to achieve an enhanced iron absorption in humans. Means to activate the phytase included dough preparation at different pH values and temperature as well as pre-soaking of the sorghum flour before baking. The phytic acid and mineral content was measured by high-performance ion chromatography. In the composite bread without pH adjustment of the dough, the phytate content was 1.58 μmol/g. After adjustment of the dough pH to 4.3, the phytate content in the composite bread decreased to 0.86 μmol/g. Soaking of the sorghum flour at 22°C for 3 h at pH 4.3 before baking, further decreased the phytate content to 0.58 μmol/g. Increasing the soaking temperature to 37°C and addition of 10% wheat flour resulted in a phytate content of 0.14 μmol/g in the composite bread, that is a reduction by 97% of the initial phytate content. The phytate:iron molar ratio was then 0.70 and the phytate:zinc molar ratio was 1.1 that is expected to have a positive effect on the absorption of both minerals in humans.
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| 2. |
- Vilanculos, Serafina, 1961, et al.
(författare)
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Phytate degradation in composite wheat/cassava/sorghum bread: Effects of phytase-secreting yeasts and addition of yeast extracts
- 2024
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Ingår i: Food Science and Nutrition. - 2048-7177. ; 12:1, s. 216-226
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Tidskriftsartikel (refereegranskat)abstract
- Iron deficiency anemia is highly prevalent in developing countries due to the consumption of cereal-based foods rich in phytate that chelates minerals such as iron and zinc making them unavailable for absorption by humans. The aim of the present study was to degrade phytic acid in composite flour (wheat/cassava/sorghum) bread by the addition of phytase-producing yeasts in the baking process to achieve a phytate-to-iron molar ratio
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| 3. |
- Vilanculos, Serafina, 1961, et al.
(författare)
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Phytate degradation in composite wheat/cassava/sorghum bread: Effects of preincubation of Pichia kudriavzevii TY13 and presence of yeast extract.
- 2022
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Ingår i: African Journal of Food Science. - 1996-0794. ; 16:12, s. 310-318
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Tidskriftsartikel (refereegranskat)abstract
- Diet based on whole cereal flours is associated with a high prevalence of iron deficiency anemia and zinc deficiency in low/middle-income countries. Such flours contain high content of phytate that chelates minerals such as iron and zinc, making them unavailable for absorption by humans. To improve the mineral absorption, a phytate:iron molar ratio <1 and a phytate:zinc molar ratio <5 is needed to be achieved. This study aimed to improve the phytate degradation in composite wheatcassava-whole sorghum flour bread by adding a phytase releasing yeast Pichia kudriavzevii TY13 in baking, preincubated or not, with addition of yeast extract. The phytate and mineral contents were measured by high-performance ion chromatography. Addition of P. kudriavzevii TY13 to the composite flour dough and fermentation for 2 h at room temperature resulted in a 98% phytate degradation. However, the same phytate reduction in the composite bread was achieved after 1 h fermentation at room temperature with addition of preincubated P. kudriavzevii TY13 plus yeast extract. Increasing the fermentation temperature to 30°C, the phytate content was equally low after fermentation for 1 h with P. kudriavzevii TY13 (preincubated or not) plus yeast extract. In conclusion, a faster reduction of phytate in composite bread was obtained by increasing the fermentation temperature, and addition of P. kudriavzevii TY13 (preincubated or not) with added yeast extract. The phytate to iron molar ratio was then 0.2 and the phytate to zinc molar ratio 0.6, which strongly indicates an improved bioavailability of both minerals from such a bread.
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