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

In this study, the trend of VOCs of dietary fiber samples, coming from three different watermelon cultivars Citrullus lanatus L. (variety Gavina®®, Crimson Sweet, and Asahi Miyako) was investigated. This foodstuff, obtained as a by-product of residual agri-food production, has gained increasing attention because of its many bioactive components and high dietary fiber content. The result is a fibrous material for specific applications in food manufacturing, such as corrector for some functional and technological properties. In this study, a method based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to characterize the aromatic profiles of the dried raw materials. Therefore, the VOCs of the samples of the three cultivars were investigated. Experimental results have shown that watermelon fibers generate VOCs, which can be grouped into six common classes of analytes. The different distributions of the identified compounds made it possible to effectively differentiate the three cultivars studied based on their peculiar aroma profiles. In particular, Gavina®® fiber is distinguished by the high content of terpenes, Asahi Miyako by the presence of aldehydes generated as fatty acid metabolites, and Crimson Sweet by the higher content of acetyl esters.

Ion exchange capacity of synthetic zeolite L: a promising way for cerium recovery.

The increasing rare earth elements' (REE) demand to meet the market request and the current political scenario show that it is essential to find good solutions to recover these elements from waste (both industrial and mining). Zeolites are microporous materials with high cation exchange capacity, up to now only little investigated for REE recycle. Here, we propose the use of NH4+-exchanged zeolite L for Ce recovery from a very diluted solution (0.002 M), mimicking the Ce3+ concentration of the liquors deriving from the leaching of spent catalysts. The aim of this work is twofold: (i) to investigate the exploitability of zeolite L as cation exchanger in the Ce recovery; and (ii) to determine the best working conditions. The investigated process consists of a coupled cation exchange: (1) in the first exchange the NH4+ cations - present in the zeolite porosities - are exchanged with the Ce3+ ions in the solution; and (2) in the second experiment, the Ce3+ trapped into the zeolite is recovered through a further exchange with NH4. The best working conditions for Ce3+ exchange of NH4-zeolite L are: batch system, liquid/solid ratio equal to 90 mL/g and 180 mL/g, 24 h of contact at 25 °C. The resulting Ce adsorption capacity (qt) is equal to ~25 mg/g and ~39 mg/g and the removal efficiency 100% and 77% for the two tested liquid/solid ratios, respectively. The kinetics was proved to be fast and consistent with industrial timing; no energy cost for temperature setting is required; and the acid pH (~4) of the solutions does not affect the zeolite structure stability and its exchange performance. It has been demonstrated that the zeolite framework is not affected by the exchange so that the same absorbent material can be employed many times.

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

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%).

Tracing geographical origin of Lambrusco PDO wines using isotope ratios of oxygen, boron, strontium, lead and their elemental concentration.

Wine identification is one of the most important aspects in the classification of wines and consumer protection. In particular, assuring wine authenticity is a crucial issue on which researchers are focusing on. This study aims to evaluate the feasibility of using chemical (B, Pb and Sr concentration) and isotopic compositions (δ11B, 20yPb/20xPb, 87Sr/86Sr and δ18O) of wine samples to trace their geographic origins. Different PDO Lambrusco wines coming from a confined area of northern Italy were analyzed and all the isotopic systematics were monitored by using a multi collector inductively coupled plasma mass spectrometer (MC-ICP/MS). The obtained results showed that boron isotope ratio measurements led to a satisfactory degree of accuracy and precision (measured value, n = 28, 11B/10B of NIST SRM 951a equal to 4.04343 ± 0.00178, (u = 2s) with a certified value of 4.04362 ± 0.00136 (u = 2s). Furthermore, in the present study, it has been possible to highlight significant differences among samples by means of one-way analysis of variance (ANOVA) and post hoc Tukey-Kramer test. Finally, Principal Component Analysis (PCA) was also carried out in order to evaluate to which extent the different PDOs can be distinguished from each other, taking into account the whole set of geographical origin descriptors. Although δ11B provided more sensitive information, the obtained results highlighted the important to consider the synergistic combination of all the investigated parameters to trace the different samples and the need to combine the obtained values with the same parameters evaluated in the soil, water and fertilizer as well.