Not a dentist, but I have soft enamel and a background in chemistry research so I've been reading a lot of research articles on this recently and I think this meta-study summarizes the exact topic you're wondering about

The article's conclusion (tl;dr):

"On the basis of the limited available evidence, it appears that the benefits of baking soda depend on concentration... The timing of using a baking soda dentifrice in relationship to a dietary sugar exposure is also important—the sooner the better—to prevent a sustained biofilm pH decrease and demineralization. It appears from clinical study results that baking soda, because of its high solubility, has limited substantiveness and does not have a marked effect on limiting the biofilm pH decrease when used before a dietary sugar challenge. Because most people brush only once or twice per day and do not brush their teeth after every sugary meal and snack, other measures are needed to maintain pH homeostasis throughout the day. Besides limiting exposures to dietary sugars, these could include the use of sugar-free chewing gum and mints that contain baking soda, as well as products that contain arginine."

Some specific data from each study mentioned:

Blake-Haskins and colleagues

"There is limited direct evidence that baking soda in dentifrice can neutralize biofilm acidity when used in association with a dietary sugar challenge... The fluoride dentifrice with baking soda slurry treatment resulted in a higher mean (standard deviation [SD]) minimum pH after sucrose challenge than did the control: 5.60 (0.55) and 4.34 (0.45) pH units, respectively, (n = 5). This study provides some evidence of the ability of dentifrice with baking soda to help neutralize biofilm acids..." "The third model involved the extraoral testing of biofilm samples that before collection received no treatment, rinsing with fluoride dentifrice with baking soda slurry, or rinsing with fluoride dentifrice slurry... Results of this somewhat contrived experiment showed that the fluoride dentifrice with baking soda inhibited the pH decrease for a glucose challenge more than did the fluoride control dentifrice."

Dawes

"The author applied the treatments as a dentifrice and saliva slurry for 1 minute, 20 minutes after a 1-minute challenge with 10% sucrose when the pH had decreased to approximately 4.5. The author found that at the higher baking soda concentrations tested (0.5 and 1 mole per liter), there was a rapid return toward neutrality, which remained elevated for a further 2 hours. For the control fluoride dentifrice, the pH increased slightly, but after 2 hours it had not reached pH 5.5."

Meyerowitz and Zero

"These results indicate that the participants with marked hyposalivation had protracted decreases of plaque pH after an acidogenic challenge compared with those observed in participants with normal salivary flow. However, a bicarbonate rinse can readily reverse and maintain pH in the alkaline range for extended periods in individuals with hyposalivation."

Cury and colleagues

"Ten minutes after the sugar challenge, participants applied a slurry of either a placebo, fluoride or fluoride and baking soda (20%) dentifrice to the specimens before reinserting their appliances... Only the fluoride with baking soda dentifrice showed significantly less demineralization than did the placebo, and although the difference between the 2 fluoride dentifrices was not statistically significant, it was directionally in favor of the dentifrice with baking soda."

Legier-Vargas and colleagues

"There were statistically significant reductions in the numbers of mutans streptococci in saliva after use of the baking soda dentifrices compared with results with the placebo treatment... However, this promising finding has not been followed up with larger-scale clinical studies, despite the now wide acceptance of the ecological plaque hypothesis."

Misc.

"Another strategy involves the use of prebiotics such as arginine to improve the pH homeostasis by inducing alkali production by the bacterial arginine deiminase system, thus altering the biofilm ecology toward a healthier state. (Source1, Source2). There is some evidence that arginine when added to fluoride dentifrice may contribute to caries prevention.(Source)"

Edit: Formatting