Physicochemical, microbiological, and nutrimental quality of tomato industrial by-product and its valorization as source of carotenoid rich oil

Abstract

Objective: To valorize an industrial tomato byproduct from the Northwest Mexico based on the evaluation of its physicochemical, microbiological, and nutrimental quality and its potential as functional ingredient to obtain a carotenoids rich oil.

Design/methodology/approach: The tomato by-product was collected form the food industry and it was oven dried. Fresh and dry tomato by-product quality was evaluated through physicochemical, microbiological, proximal composition, dietary fiber, and minerals analysis. HPLC carotenoids analysis was performed from the Soxhlet n-hexane extracted oil and dry-byproduct.

Results: The by-product showed 81 and 9.7% of humidity; 0.26 and 0.53% meq of citric acid for titratable acidity in fresh and dried, respectively and 4.74 °Brix in fresh. The color gets paler due to the drying process, turning less red. The aerobic mesophylls, total coliforms and fungi and yeasts microbiological analysis in fresh by-product (170, <10, <10 CFU/g, respectively) and dried (180, <10, ?95 UFC/g, respectively), proved their acceptable microbiological safety. It stands out the dietary insoluble (52%) and soluble (9%) fiber, protein (14%), lipids (9.09%) content, as well as Mn>Zn>Fe>Cu, and K>P>Ca>Mg>Na. The carotenoids rich oil concentrated 13 times more lycopene (4.98 mg/g) and twice ?-carotene (0.48 mg/g) content, compared to the dry by-product from which it comes (0.38 mg/g and 0.22 mg/g, respectively).

Limitations on study/implications: Great efforts were required to dry high amounts the tomato industrial by-product.

Findings/Conclusion: The tomato industrial by-product from Northwest Mexico possess suitable physicochemical, microbiological, and nutrimental quality for its use as a functional ingredient for the generation of new products, for example a carotenoid rich oil.