Fermented Rice and Tripeptides VPP and IPP
Fermented rice does not naturally contain the tripeptides Valine-Proline-Proline (VPP) and Isoleucine-Proline-Proline (IPP), as these bioactive peptides are specifically found in fermented milk products.
Origin of VPP and IPP Tripeptides
The bioactive tripeptides VPP and IPP are primarily associated with fermented milk products, not fermented rice. Research evidence clearly demonstrates that:
- These tripeptides are derived from milk casein through fermentation processes, particularly using Lactobacillus helveticus 1, 2
- VPP and IPP have been specifically identified in fermented milk products where they demonstrate angiotensin-converting enzyme (ACE) inhibitory activity 1
- Studies examining the antihypertensive effects of these peptides consistently use fermented milk as the source, not rice or other grain products 2
Fermentation and Bioactive Compounds
While fermented foods in general offer health benefits, the specific bioactive compounds vary significantly based on the starting food material:
- Fermented foods can increase microbiome diversity and reduce proinflammatory cytokines 3
- Different fermented foods contain different probiotic strains with varying benefits 3
- Fermented milk products specifically contain acid-resistant Lactobacillus and Bifidobacterium strains that have demonstrated survival through the GI tract 3
Production of VPP and IPP
The research clearly shows that these specific tripeptides require particular conditions to form:
- VPP and IPP are not generated from beta-casein by normal gastrointestinal enzymes; the fermentation step with specific bacterial strains is necessary to produce these antihypertensive tripeptides 4
- Once formed, VPP and IPP are resistant to digestive enzymes, allowing them to remain intact in the intestine until absorption 4
- Studies have demonstrated that these peptides can induce nitric oxide production in endothelial cells, contributing to their antihypertensive effects 5
Fermented Rice Properties
While fermented rice does not contain VPP and IPP, it may offer other health benefits:
- Fermented foods in general can help normalize disturbed gut microbiota and regulate intestinal transit 3
- Whole grains, including rice, contain various beneficial compounds such as antioxidants, phenolic acids, flavonoids, and tocopherols 6
- Fermentation processes can enhance the nutritional properties of foods through enzymatic conversions of dietary components 6
In conclusion, while fermented rice may have various health benefits, the specific tripeptides VPP and IPP are uniquely associated with fermented milk products and are not found in fermented rice.