Could blueberry vinegar tackle memory loss?

I don't know and neither will your doctor. Don't do this.
https://www.mdlinx.com/internal-medicine/top-medical-news/article/2017/12/21/7498426/?

Healthline/Medical News Today

Scientists might have discovered a potential new treatment for dementia, in the form of blueberry vinegar. In the recent study, researchers show how the fermented product improved short-term memory in mice with amnesia.
Dementia is one of the fastest-growing health burdens across the globe, with one person developing the disease every 3 seconds.
It is estimated that 50 million people worldwide live with dementia. By 2050, this number is expected to reach 131.5 million.
Alzheimer's disease is the most common form of dementia, accounting for around 60–80% of all cases. It is characterized by problems with learning and memory, and it affects around 5.5 million adults in the United States alone.
Shocking statistics such as these highlight the desperate need for new ways to prevent and treat dementia.
Previous research has suggested that some natural compounds, such as those in blueberries, may help to reduce dementia-related memory loss.
As the researchers of the latest study note—including Beong Ou Lim, of Konkuk University in the Republic of Korea—research has shown that fermentation can increase the bioactivity of natural compounds.
They write, "Fermented products, such as vinegar, might act to preserve the phenolic compounds that are easily oxidized during food processing and that are impacted by factors, such as maturity, storage, and processing."
With these factors in mind, Lim and colleagues sought to investigate whether or not vinegar made from blueberries might be effective for reducing memory loss.
The team recently published its findings in the Journal of Agricultural and Food Chemistry.
Short-term memory improved in mice
In order to reach their findings, the scientists induced amnesia in mice by giving them a drug called scopolamine. The mice were then given 120 milligrams per kilogram of blueberry vinegar or 120 milligrams per kilogram of blueberry extract every day for 1 week.
The team found that the mice given the blueberry vinegar showed a reduction in the breakdown of acetylcholine in their brains. Low levels of acetylcholine have been identified in the brains of people with Alzheimer's disease, the authors note.
The study also revealed that blueberry vinegar led to a rise in brain-derived neurotrophic factor in the mice, which is a protein that plays a role in the growth and maintenance of nerve cells.
The researchers tested the memory of the mice with Y-maze tests and avoidance tests. They found that the blueberry vinegar led to better performances in both tests, which they say demonstrates its potential to boost short-term memory.
Commenting on the potential implications of their findings, the researchers write:

"BV [blueberry vinegar] may be a promising functional material or food for the protective agents of amnesia-related cognitive impairment."

That said, the team notes that further studies are needed to confirm whether or not blueberry vinegar can improve memory problems in people with dementia.
—Honor Whiteman