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"How does adding baking soda affect persimmon bread?"

Hi Anne and Sue,

I was making persimmon bread the other night, and all the recipes I found told me to add baking soda to the pulp to stiffen it. I followed the instructions, and after letting it sit for about five minutes, the pulp became a solid, but somewhat gelatinous, mass. The persimmon bread turned out beautifully, very moist and fluffy. I’m wondering if this step had anything to do with it, and if it would be a good step in banana, pumpkin, or other breads.

Robin from San Francisco


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Hi Robin,

Depending on the particular cultivar used, the growing conditions, and the degree of ripeness, persimmons can be highly astringent. The components that create astringency and make your mouth pucker are called tannins. Tannins can be abundant in persimmons. The squat Fuyu persimmon has no tannins and can be eaten while still firm. In contrast, the more common, acorn-shaped Hachiya remains astringent until its skin dulls and it has become so ripe that the flesh inside is almost jellylike.

Tannins play an integral part in the manufacture of a fascinating number of products—from animal food to leather to paper to red wine. Research in various fields indicates that an alkaline pH inactivates tannins. Adding baking soda, an alkali, directly to the persimmon pulp is an attempt to reduce astringency and to ensure that the tannins cause no further reactions as the batter is mixed.
When persimmons are beaten to a pulp, tannins form complexes with carbohydrates, causing the pulp to stiffen to a gel-like consistency. When baking soda is added, a reaction with the moist and slightly acidic persimmon creates carbon dioxide (CO2), which also plays a role in encouraging the pulp to thicken. With other fruits, this gelling doesn’t happen because they aren’t as high in tannins. Your persimmon bread was light and fluffy because CO2 likely became trapped in the gel.

It’s better to not add baking soda to mashed banana and pumpkin when making breads with these fruits. Adding baking soda to these moist, acidic ingredients initiates a reaction that releases CO2. This happens extremely quickly with fruits that don’t form a gel. By the time the batter is mixed together, the CO2 has escaped.

Persimmon bread sounds delicious, and it’s something we’ve never made. Unfortunately, persimmons are now out of season in our markets, so we’ll have to wait. Would you consider posting the recipe for persimmon bread on the Forum? We’d welcome any further insights on making this bread.

Great to hear from you, Robin.
Anne & Sue




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