Fermented unripe tomato paste – Development of innovative salad dressings as a contribution to circular economy

Abstract

As food trends evolve towards sustainable, healthy, and mildly processed products, it is essential to consider new food sources, which contribute to positive changes in the food industry and originate interesting new products. For the tomato industry, where only completely red tomatoes are used, unripe and non-red tomatoes constitute an important by-product, with important losses in the field of a perfectly edible vegetable food source. To give value to this unripe tomato, a fermentation with a consortium of lactic acid bacteria and yeast was previously optimized, originating an acidic pulp with optimized nutritional characteristics and great potential for salad dressing development. Pulp's texture was improved with two hydrocolloid systems: 0.5 g/100 g of xanthan gum; and a mixed system of xanthan gum and kappa-carrageenan (0.1 g/100 g each). After rheology optimization, spices and condiments were added to the thickened fermented pulp, and promising tasty sauces were obtained. These sauces were presented to a consumers’ panel, with good acceptance. The production of these new healthy sauces aims to mitigate unripe tomato waste, adding value to the tomato industry by using a major industrial by-product.