Potential Synergy of Organic Acidifiers, Calcium Soaps of Fatty Acids, and Emulsifiers in Poultry Nutrition: A Conceptual Model and Hypothetical Formulation

Background: Following the ban on growth-promoting antibiotics in the European Union in 2006 (Regulation 1831.2003) and the spread of similar restrictions in other countries, researchers have focused on alternative feed additives. Organic acidifiers, calcium fatty acid powder (calcium salts of fatty acids), and emulsifiers each have positive effects on growth performance, gut health, and nutrient digestibility. Objective: This review analyzes the mechanisms of action of these three additives, evaluates the scientific evidence for their synergy, and proposes a conceptual model for a triple supplement.Methods: A systematic search was conducted using the keywords organic acid, acidifier, calcium salt of fatty acid, calcium soap, emulsifier, lysophospholipid, broiler, and poultry nutrition in PubMed, Scopus, ScienceDirect, Google Scholar, and Web of Science from 2000 to 2025. Out of 482 initial records, after removing duplicates (127) and irrelevant records (301), 54 original articles, 8 systematic reviews, 3 meta-analyses, and 1 patent were included in the final review.Results: Acidifiers reduce crop pH to 3.5–4.2, increase pepsin activity, and reduce Salmonella by up to 1.5 log CFU. Calcium fatty acid powder, with an energy density of about 7,200 kcal/kg, provides a stable and oxidation-resistant energy source. Emulsifiers improve fatty acid absorption by increasing lipid–lipase contact. Evidence suggests that the triple combination creates a complementary chain: acidifiers optimize the digestive environment, emulsifiers increase enzyme access to substrate, and calcium fatty acid powder supplies a stable energy substrate. To date, no published in vivo trial has directly evaluated the triple combination; therefore, the proposed model is based on mechanistic inference from single-component studies.Conclusion: The triple model has high potential for improving performance, gut health, and economic efficiency, but definitive proof of synergy requires in vivo trials. A preliminary economic analysis suggests that an extra cost of about USD 2.12 per ton of feed could be offset by a 3% improvement in feed conversion ratio within one production cycle.Highlights:· Acidifiers, calcium fatty acid powder, and emulsifiers each alone have positive but limited effects on poultry performance and gut health. · The triple combination creates a synergistic chain: pH optimization, enzyme access to fat, and stable energy supply. · Proposed conceptual formulation: 50% calcium fatty acid powder, 35% acidifier, 5% emulsifier, and 10% carrier. · Recommended dosage: 0.10–0.15% in drinking water and 0.15–0.20% in feed.· In vivo trials are essential to confirm synergy and optimize dosage.Limitations:· Lack of in vivo data for the triple combination · Possible complexation of calcium with organic acids · pH differences among digestive tract segments · Physical compatibility of ingredients · Species differences (broiler vs. layer) · Product stability at high temperature (pelleting) · Need to adjust dosage based on water qualityFuture Research Suggestions:1. In vivo trials at different doses 2. Evaluation of intestinal morphology, microbial population, and lipid metabolism gene expression 3. Comparison of the triple product with individual components 4. Optimization of ingredient ratio and type 5. Evaluation of product stability under storage and processing conditions 6. Realistic economic assessment 7. Investigation of safety and regulatory aspectsKeywords: acidifier, calcium fatty acid powder, emulsifier, poultry nutrition, synergy, growth performance, gut health Conflict of Interest: The author declares no conflict of interest.Funding: This study received no external funding.