Comparative Analysis of VOCs from Winter Melon Pomace Fibers before and after Bleaching Treatment with H2O2

Abstract

In this study, the trend of Volatile Organic Compounds (VOCs) in dietary fiber samples from the winter melon (Cucumis Melo var. Inodorus, Yellow Canary type) were investigated. This foodstuff, obtained as a by-product of agri-food production, has gained increasing attention and is characterized by many bioactive components and a high dietary-fiber content. As regards fiber, it is poorly colored, but it may be whitened by applying a bleaching treatment with H2O2. The result is a fibrous material for specific applications in food manufacturing, for example, as a corrector for some functional and technological properties. This treatment is healthy and safe for consumers and widely applied in industrial food processes. In this study, a method based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC-MS) was applied for the characterization of the aromatic profile of the dried raw materials. Furthermore, VOC variation was investigated as function of the bleaching treatment with H2O2. The bleached samples were also analyzed after a long storage period (24 months), to assess their stability over time. As a result, the VOC fraction of the fresh raw fiber showed nine classes of analytes; these were restricted to seven for the bleached fiber at t0 time, and further reduced to four classes at the age of 24 months. Alcohols were the main group detected in the fresh raw sample (33.8 % of the total chromatogram area), with 2,3-butanediol isomers as the main compounds. These analytes decreased with time. An opposite trend was observed for the acids (9.7% at t0), which increased with time and became the most important class in the 24-month aged and bleached sample (57.3%).

VOCs Analysis of Three Different Cultivars of Watermelon (Citrullus lanatus L.) Whole Dietary Fiber

“…Procedures for HS-SPME-GC-MS measurements have been proposed and applied in our previous studies [5,54] on the aroma profiles of similar plant-based samples.…”

“…Furthermore, it is a precious source of mineral salts, in particular K, Mg, Ca, and Fe [3], and of some vitamins: one cup of diced watermelon covers about 21% of the daily requirement of vitamin C and 17% of vitamin A [1]. Finally, it contains a good amount of dietary fiber, the consumption of which is strongly recommended in the human diet by several well-documented reports, including those of the Food and Agriculture Organization of the United Nations (FAO) [5][6][7][8].…”

“…These species cause serious consequences for the microbial flora of the soil, to the point of even procuring sterility [13]. In this context arises the need to recover the residual products of primary agronomic productions, i.e., the massive quantity of fruit that remains in a pre-waste condition on the crop field, and their precious nutritional components [5,14,15].…”

Waste By-Product of Grape Seed Oil Production: Chemical Characterization for Use as a Food and Feed Supplement

“…It is well known that the agri-food sector produces a large amount of cellulosic by-products [ 1 ]. To address the climate emergency and reduce the environmental impact, agro-industrial waste from mechanical, chemical, or biological processes can be used for new products and applications [ 2 ]. These recovery and enhancement activities are the basis of the circular economy, aiming at “zero waste” society, in perfect agreement with Agenda 2030 [ 3 , 4 ].…”

Volatile Aroma Compounds of Gavina® Watermelon (Citrullus Lanatus L.) Dietary Fibers to Increase Food Sustainability

“…Pursuing our previous works regarding the recovery of dietary fiber from agri-food waste [5,17,18], in this study, we obtained and examined the whole dietary fiber (WDF) from watermelon pomace. Pomace is the pulp residue remaining after the fruit has been crushed to extract its juice.…”