Traditional mayonnaise is an oil-in-water emulsion containing 65-80% vegetable oil, 5-8% egg yolk and a spiced-water phase. The latter typically includes vinegar, mustard, salt and sugar. The oil is present as dispersed droplets with an average size ranging from 2–10 microns.
Consumers demand low-calorie products with the same taste and feel as traditional versions. But lowering the amount of oil in mayonnaise will lead to a less dense packing of the dispersed oil droplets, which means reduced viscosity and texture. Various thickening and gelling compounds can be added to the water phase to boost viscosity and texture. Starch is frequently used, but other hydrocolloids are also common.
Many consumers have an opinion on what is “good quality” mayonnaise – and those opinions differ widely around the world. But it is not easy to link these opinions to measurable quality parameters. For producers, mayonnaise quality is often characterized by a combination of sensory evaluations and laboratory analyses. Mayonnaise commercials and labels often highlight texture attributes using words like as “creamy”, “smooth” and “thick”. Indeed, the texture influences the eating experience through visual appearance, handling feel and in-mouth feel.
Mayonnaise producers need to be able to control the quality of every batch. Apart from having a sensory panel of testers, who evaluate parameters such as appearance, texture and mouthfeel, laboratory analyses are also performed based on rheology. This is the study of how materials that have both solid and fluid characteristics flow and deform when subjected to a force.
A key element in mayonnaise processing is emulsification, which includes breaking up the oil droplets. An oil droplet is broken up when the fragmenting stresses acting on it exceed the stabilizing stresses opposing droplet deformation, and do so for a certain period of time.
High-intensity mixers such as high-speed rotor-stator mixers or colloid mills are commonly used. The energy from these devices is dissipated in a relatively small product volume, which creates high levels of local energy dissipation rates and thereby small oil droplets. These mixers can be combined with, or in, mixing tanks in various ways, and the complete mixing system can be set up to operate in both batch and continuous production.
Mayonnaise’s quality attributes are influenced not only by ingredient types and composition, but also by equipment type, processing parameters and scale of production.
And then dive deep into the topic by downloading our white paper: Navigating the mayonnaise maze: taking the guesswork out of production.