Industrial production of vegetable products usually requires the use of additives and thermal treatments for achieving satisfactory sensory and keeping qualities. However, the use of additives is against consumers' urge for naturalness. Moreover processing may destroy nutritionally valuable compounds of vegetables.
The study of Juvonen et al (2015) explored the impact of fermentation with different exopolysaccharide (EPS) producing lactic acid bacteria (LAB) on rheological, chemical and sensory properties of puréed carrots in water, as a vegetable model, with the focus on texture formation. The screening of 37 LAB strains for starter selection revealed 16 Lactobacillus, Leuconostoc and Weissella strains capable of EPS (dextran, levan, and/or β-glucan) production in the carrot raw material.
Fermentations with five out of six selected EPS producers modified perceived texture of the liquid carrot model (p < 0.05). The formation of low-branched dextran correlated with perceived thickness, whereas the production of β-glucan correlated with perceived elasticity. Low-branched dextran producing Weissella confusa and Leuconostoc lactis strains produced thick texture accompanied by pleasant odour and flavour. The fermentation with the selected EPS-producing LAB strains is a promising clean label approach to replace hydrocolloid additives as texturizers in vegetable containing products, not only carrot.
For more information:
Juvonen R., Honkapää K., Maina NH., Shi Q., Viljanen K., Maaheimo H., Virkki L., Tenkanen M., Lantto R. "The impact of fermentation with exopolysaccharide producing lactic acid bacteria on rheological, chemical and sensory properties of pureed carrots (Daucus carota L.)" Int J Food Microb. 2015, 207, 109-118.