ANSWER

Cultured whey is naturally derived anti-microbial preservatives that contain propionic acid that can be used in bakery products (WIPO Patent No. WO2013025606 A2, 2013; Albers-Nelson, 2010). It is produced by the fermentation of whey (milk).

References

Albers-Nelson, R. (2010). Clean label mold inhibitors for baking. Stillwater, Oklahoma: Oklahoma State University.

Bright, P., Baumer, C., Mckeown, W. & Jackson, C. (2013). Natural mold inhibitor and methods of using same. WIPO Patent No. WO2013025606 A2.