Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids
In this study, a model system of firm tofu (pressed gel) was prepared to study how the coagulation mechanism—acidification with glucono δ-lactone (GDL) or coagulation with magnesium sulphate (MgSO<sub>4</sub>)—affected the physical properties of the gels along with their in vitro proteol...
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| Format: | Article |
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MDPI AG
2021-01-01
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| Series: | Foods |
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| Online Access: | https://www.mdpi.com/2304-8158/10/1/154 |
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| author | Marina Marinea Ashling Ellis Matt Golding Simon M. Loveday |
| author_facet | Marina Marinea Ashling Ellis Matt Golding Simon M. Loveday |
| author_sort | Marina Marinea |
| collection | DOAJ |
| description | In this study, a model system of firm tofu (pressed gel) was prepared to study how the coagulation mechanism—acidification with glucono δ-lactone (GDL) or coagulation with magnesium sulphate (MgSO<sub>4</sub>)—affected the physical properties of the gels along with their in vitro proteolysis (or extent of proteolysis). The two types of gels were also fortified with 3.5 mM protocatechuic (PCA) and coumaric acid (CMA) to test whether they can be used as bioactive delivery systems. Texture analysis showed that all MgSO<sub>4</sub>-induced gels (fortified and control) had a higher hydration capacity and a weaker texture than the GDL-induced gels (<i>p</i> < 0.05). MgSO<sub>4</sub> gels had almost double proteolysis percentages throughout the in vitro digestion and showed a significantly higher amino acid bioaccessibility than the GDL gels (essential amino acid bioaccessibility of 56% versus 31%; <i>p</i> < 0.05). Lastly, both gel matrices showed a similar phenolic acid release profile, on a percentage basis (<inline-formula><math display="inline"><semantics><mo>~</mo></semantics></math></inline-formula>80% for PCA and <inline-formula><math display="inline"><semantics><mo>~</mo></semantics></math></inline-formula>100% for CMA). However, GDL gels delivered significantly higher masses of bioactives under simulated intestinal conditions because they could retain more of the bioactives in the gel after pressing. It was concluded that the coagulation mechanism affects both the macro- and microstructure of the soy protein pressed gels and as a result their protein digestibility. Both pressed gel matrices are promising delivery systems for bioactive phenolic acids. |
| first_indexed | 2024-03-09T04:58:41Z |
| format | Article |
| id | doaj.art-f8a613831d93430a825c1c9b2db2c6fb |
| institution | Directory Open Access Journal |
| issn | 2304-8158 |
| language | English |
| last_indexed | 2024-03-09T04:58:41Z |
| publishDate | 2021-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Foods |
| spelling | doaj.art-f8a613831d93430a825c1c9b2db2c6fb2023-12-03T13:03:02ZengMDPI AGFoods2304-81582021-01-0110115410.3390/foods10010154Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic AcidsMarina Marinea0Ashling Ellis1Matt Golding2Simon M. Loveday3Riddet Institute, Massey University, Palmerston North 4442, New ZealandRiddet Institute, Massey University, Palmerston North 4442, New ZealandRiddet Institute, Massey University, Palmerston North 4442, New ZealandRiddet Institute, Massey University, Palmerston North 4442, New ZealandIn this study, a model system of firm tofu (pressed gel) was prepared to study how the coagulation mechanism—acidification with glucono δ-lactone (GDL) or coagulation with magnesium sulphate (MgSO<sub>4</sub>)—affected the physical properties of the gels along with their in vitro proteolysis (or extent of proteolysis). The two types of gels were also fortified with 3.5 mM protocatechuic (PCA) and coumaric acid (CMA) to test whether they can be used as bioactive delivery systems. Texture analysis showed that all MgSO<sub>4</sub>-induced gels (fortified and control) had a higher hydration capacity and a weaker texture than the GDL-induced gels (<i>p</i> < 0.05). MgSO<sub>4</sub> gels had almost double proteolysis percentages throughout the in vitro digestion and showed a significantly higher amino acid bioaccessibility than the GDL gels (essential amino acid bioaccessibility of 56% versus 31%; <i>p</i> < 0.05). Lastly, both gel matrices showed a similar phenolic acid release profile, on a percentage basis (<inline-formula><math display="inline"><semantics><mo>~</mo></semantics></math></inline-formula>80% for PCA and <inline-formula><math display="inline"><semantics><mo>~</mo></semantics></math></inline-formula>100% for CMA). However, GDL gels delivered significantly higher masses of bioactives under simulated intestinal conditions because they could retain more of the bioactives in the gel after pressing. It was concluded that the coagulation mechanism affects both the macro- and microstructure of the soy protein pressed gels and as a result their protein digestibility. Both pressed gel matrices are promising delivery systems for bioactive phenolic acids.https://www.mdpi.com/2304-8158/10/1/154soy protein gelsfirm tofuprotocatechuic acidcoumaric acidglucono δ-lactonemagnesium sulphate |
| spellingShingle | Marina Marinea Ashling Ellis Matt Golding Simon M. Loveday Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids Foods soy protein gels firm tofu protocatechuic acid coumaric acid glucono δ-lactone magnesium sulphate |
| title | Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids |
| title_full | Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids |
| title_fullStr | Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids |
| title_full_unstemmed | Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids |
| title_short | Soy Protein Pressed Gels: Gelation Mechanism Affects the In Vitro Proteolysis and Bioaccessibility of Added Phenolic Acids |
| title_sort | soy protein pressed gels gelation mechanism affects the in vitro proteolysis and bioaccessibility of added phenolic acids |
| topic | soy protein gels firm tofu protocatechuic acid coumaric acid glucono δ-lactone magnesium sulphate |
| url | https://www.mdpi.com/2304-8158/10/1/154 |
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