ABSTRACT
Food by-products are a major concern with a direct impact on the economy, society, and environment. The valorisation of these by-products could be an advantageous approach to face the increase in food waste since it can compromise environmental health and food sustainability. On the other hand, this valorisation would allow the development of new food products with health benefits for the population. Cucumis melo L. is a highly consumed fruit all over the world since it has excellent sensory and nutritional qualities, being also a good source of bioactive compounds. However, its peel and seeds are usually discarded. The aim of this study was to evaluate the potential of melon peel flour as a functional ingredient for innovative food products. For that, two different formulations containing melon peel flour were developed (a biscuit and a muffin) by replacing a conventional flour (wheat flour) in different percentages (50% and 100%, respectively). The nutritional composition, total phenolic content, and antioxidant potential of the developed products were studied, showing a high content of fibre, high levels of phenolic compounds and good sensory acceptability. These results show that it is possible to enrich different foods with melon peel flour in order to improve their nutritional properties, contributing to improving public health, simultaneously valorising a usually rejected by-product, reducing food waste and the environmental impact.
Subject(s)
Cucurbitaceae , Refuse Disposal , Flour/analysis , Triticum , SeedsABSTRACT
Os objetivos deste trabalho foram avaliar o efeito da germinação no teor de macronutrientes e da desidratação em compostos bioativos, nutrientes e atividade antioxidante de farinhas das leguminosas Phaseolus lunatus L. e Cajanus cajan (L. Millsp.) germinadas. As condições de germinação foram controladas em laboratório e as amostras foram submetidas à desidratação térmica (55°C) e liofilização. Foram realizadas as análises de composição centesimal, fenólicos totais flavonoides, atividade antioxidante (DPPH, FRAP), perfil de ácidos graxos (CG-FID) e de vitâmeros de tocoferol (HPLC- DAD). A germinação das leguminosas promoveu aumento de proteínas, lipídios e carboidratos. O processamento térmico para desidratação contribuiu para perdas de proteínas, lipídios, cinzas, e maior atividade antioxidantes em ambas as espécies. O perfil de ácidos graxos e vitâmeros de tocoferol mostraram-se com variações que dependem do tipo de leguminosa e condições de processamento, podendo ser positivas ou negativas. Farinhas de leguminosas germinadas pode ser uma alternativa para a inserção na dieta ou em formulações alimentícias e as condições de processamento devem ser monitoradas com intuito de otimiza propriedades nutritivas e funcionais.
The objectives of this work were to evaluate the effect of germination on macronutrient content and dehydration on bioactive compounds, nutrients and antioxidant activity of flours from germinated Phaseolus lunatus L. and Cajanus cajan (L. Millsp.) legumes. The germination conditions were controlled in the laboratory and the samples were submitted to thermal dehydration (55°C) and lyophilization. Analyses were carried out for centesimal composition, total phenolic flavonoids, antioxidant activity (DPPH, FRAP), fatty acid profile (GC-FID) and tocopherol vitamers (HPLC-DAD). Germination of the legumes promoted an increase in proteins, lipids and carbohydrates. Thermal processing for dehydration contributed to losses of proteins, lipids, ash, and higher antioxidant activity in both species. The profile of fatty acids and tocopherol vitamers showed variations that depend on the type of legume and processing conditions, and can be positive or negative. Sprouted legume flours can be an alternative for insertion in the diet or in food formulations and the processing conditions must be monitored in order to optimize nutritional and functional properties.
Los objetivos de este trabajo fueron evaluar el efecto de la germinación sobre el contenido en macronutrientes y de la deshidratación sobre los compuestos bioactivos, los nutrientes y la actividad antioxidante de harinas de leguminosas germinadas de Phaseolus lunatus L. y Cajanus cajan (L. Millsp.). Las condiciones de germinación se controlaron en el laboratorio y las muestras se sometieron a deshidratación térmica (55°C) y liofilización. Se realizaron análisis de composición centesimal, flavonoides fenólicos totales, actividad antioxidante (DPPH, FRAP), perfil de ácidos grasos (GC-FID) y vitaminas tocoferol (HPLC-DAD). La germinación de las leguminosas promovió un aumento de proteínas, lípidos y carbohidratos. El procesado térmico para la deshidratación contribuyó a pérdidas de proteínas, lípidos, cenizas y a una mayor actividad antioxidante en ambas especies. El perfil de ácidos grasos y vitaminas tocoferol mostró variaciones que dependen del tipo de legumbre y de las condiciones de procesado, pudiendo ser positivas o negativas. Las harinas de leguminosas germinadas pueden ser una alternativa para su inserción en la dieta o en formulaciones alimentarias y las condiciones de procesado deben ser monitorizadas para optimizar las propiedades nutricionales y funcionales.
ABSTRACT
Olive pomace, an olive oil processing byproduct, can be upcycled and meet the current demand for natural and sustainable food ingredients. In this work, a patented process was used to obtain a functional ingredient from different olive pomaces. The nutritional, chemical and antioxidant profiles, as well as the antimicrobial activity against S. aureus, E. coli and C. albicans, were investigated for the first time. The amount of phenolics ranged between 3.1 and 3.8 g gallic acid eq./100 g in all samples and flavonoids between 2.0 and 3.2 g catechin eq/100 g. No significant differences were found regarding the antioxidant activity. The total fat varied between 5 and 11%, α-tocopherol being the major vitamer and oleic acid the main fatty acid. The protein and ash contents were 1-4% and 10-17%, respectively. The functional ingredient with a higher hydroxytyrosol content (220 mg/100 g) also presented the best minimal inhibitory concentration against the tested bacteria. No activity against C. albicans was verified. This new functional ingredient presents the potential to be used as a natural preservative or as a nutritional profile enhancer. Moreover, it can be an advantageous ingredient in food products, since it comprises specific lipid and hydrophilic bioactive compounds usually not present in other plant extracts.
