As part of the secondary data analysis of Harnack et al. [5], we analyzed the PRAL value of n = 37 plant-based ground beef alternatives (Table 1). PRAL values varied substantially across the examined foods, and ranged from −2.89 mEq/100 g to 16.84 mEq/100 g. The mean PRAL value was 4.04 ± 4.73 mEq/100 g and thus suggested a moderately acidifying potential (PRAL > 0 mEq/d). Almost 80% of the examined items had a PRAL value < 8 mEq/100 g, and thus ranked lower than conventional pork and beef meat, which both have PRAL values of approximately 8 mEq/100 g.

The protein content per 100 g cooked portion ranged from 5.53 g to 25.65 g and was positively associated with PRAL (r = 0.73, p < 0.001). Significant inverse associations with PRAL were found for the magnesium (r = −0.41, p = 0.01) and potassium content (r = −0.69, p < 0.001). The “Beyond Beef Crumbles Beefy” and the “Morningstar Farms Meat Lovers Vegan Burgers” were the most acidifying food items, with PRAL values of 16.84 and 13.28 mEq/100 g, respectively.

Further to that, we used data from Ložnjak-Švarc, who performed a nutrient analysis of n = 58 products with protein derived from egg white, mycoprotein, pea, soy, a combination of pea and soy, and wheat [6]. Readily available on the Danish food market, these products were divided into several groups, such as cold cuts, minced, or sausages. We adopted this classification and calculated group-specific PRAL values (Fig. 1). The mean PRAL value in this food sample was 6.15 ± 4.76 mEq/100 g. The mycoprotein- and wheat-based food items yielded the highest PRAL values, ranging from 8.92 to 13.99 mEq/100 g.

legend: based on data from Ložnjak Švarc et al. [6]. Data based on a nutrient analysis of n = 58 products with protein derived from egg white, mycoprotein, pea, soy, a combination of pea and soy, and wheat. PRAL in mEq/100 g. The blue dotted line indicates the PRAL value of a 100 g portion of beef, whereas the red dotted line indicates the PRAL value of a 100 g portion of chicken.

Finally, we analyzed data from De Marchi et al., who compared selected Italian plant-based and meat-based burgers (Supplementary Table 1) [7]. The PRAL values between both groups did not differ substantially (6.80 vs. 7.27 mEq/100 g), probably because of the rather similar protein content of the examined items. While plant-based burgers were more abundant in potassium (an alkali precursor), they also included more acidifying phosphorus.