What if citric acid is not inherently good or bad, but misunderstood because formulation context is rarely explained?

In this episode of Dental Formulator’s Playbook, Dr. Rob and co-host Tami take a deep, science-first look at one of the most widely used yet misunderstood ingredients in modern products: citric acid. Building on earlier episodes that examined citric acid’s role in foods and dental erosion, this conversation explores how citric acid is made, why it appears in everything from toothpaste to skincare to cleaners, and how its chemistry changes depending on form, concentration, and context.

Dr. Rob explains the critical distinction between citric acid and citrate, why hydration state matters for formulators, and how citric acid functions as a buffer, chelator, preservative, and flavor modifier. The discussion traces citric acid’s industrial production back to early fermentation research, its historical link to penicillin scale-up through Pfizer, and its foundational role in cellular energy via the Krebs (citric acid) cycle. The episode also examines citric acid’s use in cosmetics as an alpha hydroxy acid, in household cleaners, in laboratory sample preservation, and in encapsulated food applications.

Rather than framing citric acid as “good” or “bad,” this episode emphasizes understanding concentration, buffering, formulation design, and intended use to make informed decisions across oral care, food, skincare, and consumer products.

Key Topics Covered

1. The difference between citric acid and citrate in aqueous systems
2. Why citric acid and sodium citrate behave the same once dissolved in water
3. Hydration states of raw materials (anhydrous, monohydrate, dihydrate) and why they matter for formulation accuracy
4. How citric acid functions as a buffer in pharmaceuticals and oral care products
5. Why citric acid is considered a natural ingredient despite industrial-scale production
6. Fermentation-based production of citric acid using Aspergillus niger
7. The historical link between citric acid scale-up and penicillin mass production
8. Pfizer’s role in advancing fermentation technology during World War II
9. James Currie’s 1917 research and its lasting impact on microbial production methods
10. Why fermentation is still the dominant method for producing citric acid today
11. Citric acid’s role in metabolism through the Krebs (citric acid) cycle
12. Alpha hydroxy acids (AHAs) and citric acid’s role in skincare formulations
13. Concentration differences between dental products, foods, cosmetics, and cleaners
14. Why buffering citric acid is critical in oral care and pharmaceutical products
15. Citric acid use in household cleaners, including modern low-toxicity formulations

What if some of your most “healthy” choices for gut health are quietly eroding your teeth?

In this episode of Dental Formulator’s Playbook, Dr. Rob and co-host Tami build on Episodes 26 and 27 to explain why pH alone does not tell the full story. They explore fermented dairy (yogurt, buttermilk, fermented milks), kombucha, and prebiotic cultures like lactobacilli, plus how timing, sipping habits, and formulation choices can increase risks for erosion and caries. The conversation also expands into restorative dentistry, including a 2024 study comparing two “compomer” materials (including the sparkly kid-friendly option) and how different liquids can change surface roughness over time.

Key Topics Covered

1. Why the type of acid can predict damage better than pH alone
2. Fermented dairy basics: common pH range (about 4.0 to 4.5) and why buffering can be misleading
3. How lactobacilli tie into oral health: caries risk, acid production (lactic and sometimes acetic acid)
4. Why some “oral probiotic” mints can be a tradeoff, especially depending on your physiology
5. Kombucha pH (about 2.5 to 3.5) and why sipping over time can raise erosion risk
6. Timing matters: why yogurt or acidic drinks right before bed can be risky during low-saliva conditions
7. A children’s diet study reference: reported erosion rates tied to yogurt, orange juice, and carbonated drinks
8. A look at compomers (composite + glass ionomer hybrids): what they are and how they are used clinically
9. How exposure to cola, juice, water, and milk affected restoration surface roughness in a 2024 paper
10. Why roughness matters: plaque traps, periodontal risk, and even tooth appearance (light reflection)

Highlights and Takeaways

1. “Healthy” does not always mean tooth-friendly. Gut benefits and enamel risks can coexist.
2. Sipping style and duration can matter as much as the drink itself. The longer acids linger, the higher the risk.
3. Fermented dairy can be well-buffered yet still contribute to enamel softening, especially with frequent exposure and poor timing.
4. Lactobacilli and its role as part of the caries picture, especially alongside streptococci, depending on the model and context.
5. Restorations have their own vulnerabilities. Some materials can roughen quickly in acidic liquids, while others may develop deposits over time.
6. A rough surface is not just cosmetic. It can create plaque traps and raise oral health...

What if some of the research shaping everyday products is quietly flawed, and the system designed to correct it often chooses not to?

In this episode of Dental Formulator’s Playbook, Dr. Rob and co-host Tami take a deep, unfiltered look at scientific ethics and research accountability. Prompted by recent survey data and real-world case studies, the conversation explores how flawed or falsified research can enter the scientific record and why it so often remains there uncorrected.

Rather than focusing on isolated mistakes, this episode examines systemic behaviors. These include informal admissions, delayed accountability, and the reluctance to issue corrections or retractions even when problems are known. From high-profile superconductivity claims to modern AI-driven research, Dr. Rob explains why transparency, replication, and proper testing models are essential, especially when scientific papers are used to justify claims in oral care products and other consumer-facing technologies.

This discussion challenges listeners to think more critically about what “published” really means and how to evaluate research beyond headlines and abstracts.

Key Topics Covered

1. Findings from a published survey examining how often chemists knowingly falsify information in scientific papers
2. What falsification can look like beyond simple errors, including selective data presentation and procedural shortcuts
3. Why many researchers avoid formal corrections and how those decisions are commonly rationalized
4. Informal and non-public ways errors are addressed instead of correcting the scientific record
5. How scrutiny can occur outside traditional journals through independent review and public forums
6. A detailed case study involving high-profile superconductivity claims and failed replication attempts
7. Why highly publicized fields like AI attract attention, while similar ethics risks exist across all areas of science
8. How Dr. Rob evaluates whether research is trustworthy, relevant, and clinically meaningful
9. The role of appropriate models, controls, and independent replication in supporting oral care product claims

Highlights and Takeaways

1. Published does not mean proven. Peer-reviewed publication alone is not a guarantee of accuracy or reliability.
2. The scientific record often remains uncorrected. Many known issues are never formally addressed through corrections or retractions.
3. Replication is essential. When independent groups cannot reproduce results, confidence in those findings should decrease.
4. Models and controls matter. Meaningful positive and negative controls are critical for interpreting results responsibly.
5. Bias influences what gets promoted. Financial incentives, career pressure, and...