ISSUE FOCUS FEED & ADDITIVE MAGAZINE March 2026 25 ORGANIC ACIDS: CHARACTERISTICS AND LIMITATIONS Organic acids inhibit microbial growth in feed by reducing the internal pH of bacteria and fungi, thereby reducing their enzymatic activity to minimal levels and limiting their ability to reproduce. These products prevent the multiplication of microorganisms, but do not eliminate them completely. Their spectrum of action is more or less limited: some acids are effective only against specific groups of microorganisms (i.e., gram-positive bacteria). The combination of propionic acid with formic acid is the most commonly used, as it broadens the preservative’s spectrum of action. The main limitations of these products are: • They inhibit but do not completely eliminate microorganisms. • A relatively short duration of effect: after approximately two months they lose efficacy, and microorganisms may use the acids as an energy source to multiply again. • A limited spectrum of action: they are only effective against specific groups of microorganisms, meaning others may remain in the feed, or acid combinations become necessary. • Corrosive potential: acids may damage machinery and their application can sometimes be hazardous for workers. FORMALDEHYDE: SERIOUS CONSEQUENCES FOR ANIMALS AND HUMANS Formaldehyde has a high capacity for controlling Salmonella and has therefore been widely used to eliminate this pathogen in grains and compound feed, as well as to prevent digestive infections. Its harmful effects on human and animal health have led to a progressive reduction in the availability of formaldehyde-based products for animal feed. This is because it is a toxic and irritating substance upon contact with skin and the respiratory tract, and is potentially carcinogenic for both humans and animals. Additionally, in the digestive tract, formaldehyde reacts with hydrochloric acid, causing thermal and chemical burns in the digestive epithelium, leading to significant deterioration of productive parameters (Image 1). NATURAL PRESERVATIVES: SYNERGY BETWEEN ANTIMICROBIAL PHENOLIC COMPOUNDS Natural preservatives represent a solution that has become more popular in the industry compared to organic acids and formaldehyde, as they offer advantages that overcome the limitations of other preservatives. Alquermold Natural Plus is a clear example: a product based on the combination of cineole, cimenol ring, and isopropyl methyl-phenol, natural microbicidal molecules that synergistically eliminate a wide variety of microorganisms present in feed and cereals, including gram-positive and gram-negative bacteria, fungi, and yeasts. As a microbicidal product, it completely eliminates microorganisms, its efficacy lasts for a long time, allowing preservation of grains and compound feed for at least six months. Its mechanism is based on the disruption of the cell membrane, leading to pathogen death. RECENT SCIENTIFIC EVALUATION IN COLLABORATION WITH THE UNIVERSITY OF HELSINKI Recently, Biovet carried out an in vitro evaluation of the preservative efficacy of Alquermold Natural Plus compared with a combination of organic acids widely used in the industry. Image 1. Lesion in the gizzard of a bird exposed to formaldehyde. Burns distributed throughout the organ can be observed.
RkJQdWJsaXNoZXIy MTUxNjkxNQ==