Development of Frozen Pulps and Powders from Carrot and Tomato by-Products: Impact of Processing and Storage Time on Bioactive and Biological Properties

Helena Araújo-Rodrigues,Débora A Campos,Modesta Ratinho,Ivo M Rodrigues,Manuela E Pintado,Diva Santos

doi:10.3390/horticulturae7070185

Abstract

Vegetables and fruits have an interesting nutritional profile, rich in bioactive metabolites, holding a high antioxidant potential and health associated benefits. However, their functional properties, the shorter shelf-life due to their high-water content, and their seasonality nature lead to extensive food losses and waste. The valorization of vegetables and fruits by-products through the development of value-added products and the application of preservation methods is of utmost importance to prevent food losses and waste. In this study, based on a circular economy approach, pulps and powders of baby carrot and cherry tomato by-products were prepared. Freezing, hot air drying and storage time impact on antioxidant activity and bioactive compounds were studied. Microbiological quality and pulps viscosity were also monitored for 6 months. During the freezing storage, TPC and antioxidant capacity by ABTS and ORAC assays decreased. The antioxidant capacity by DPPH method and carotenoid content increased during the first months of freezing, but then decreased. The drying process negatively affected the antioxidant capacity as well as carotenoid and polyphenolic content compared with the fresh vegetables. Both processing methodologies positively impacted the vitamin E content. During drying storage, there were no key variations in antioxidant capacity and bioactive content.

Highlights

According to the 2019 report of the Food and Agriculture Organization of the UnitedNations, approximately 21.6% of the worldwide fruits and vegetables were lost in 2016 [1].The seasonal nature of vegetables and fruits and their short shelf-life contribute to these massive losses and waste [2,3,4]
A significant fraction of food losses results from vegetables and fruits that do not comply with commercial standards but maintain relevant nutritional and organoleptic profiles [5]
The results suggested that tomato possess a higher antioxidant capacity than carrot and that the impact of freezing in antioxidant activity largely depends on the type of vegetable

Summary

Introduction

According to the 2019 report of the Food and Agriculture Organization of the UnitedNations, approximately 21.6% of the worldwide fruits and vegetables were lost in 2016 [1].The seasonal nature of vegetables and fruits and their short shelf-life contribute to these massive losses and waste [2,3,4]. A significant fraction of food losses results from vegetables and fruits that do not comply with commercial standards but maintain relevant nutritional and organoleptic profiles [5]. Clinical and epidemiological studies have described many health-related benefits associated with a diet rich in vegetables and fruits on chronic, cardiovascular, neurological, inflammatory and some cancer diseases [3,6,7,8]. Their interesting nutritional profile results from the presence of some bioactive metabolites such as, carotenoids, flavonoids, phenolic

Methods

Results

Conclusion