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The purpose of this study was to compare two extraction processes for the production of lemon liqueur (limoncello)—the traditional maceration of lemon peels and a cyclically pressurized extraction process also known as rapid solid-liquid dynamic extraction (RSLDE) that uses a Naviglio extractor. To evaluate the extraction efficiency of the two processes, dry matter obtained by the evaporation of the extracts was used to construct kinetics curves. The dry matter was directly proportional to the amount of the active principle (terpenes) extracted and consequently to the total concentration. Alcoholic extracts were analysed by gas chromatography (GC) to monitor the extraction kinetics for major components of the terpene fraction and for minor components of essential oils. Moreover, alcoholic extracts were analysed by UV spectrophotometry to identify the more abundant chemical species, while the organoleptic tests (i.e., a consumer test) performed on the final product (limoncello) provided an indication of the taste of the final product and revealed features undetectable with instrumental analytical techniques. To better understand the phenomenon considered, a numerical simulation was performed to evaluate and compare the matter flow of extractable compounds during the process.

This chapter aims to explore the classifications, origins, and characteristics of natural beverages. Beverages are liquids suitable for human consumption, and the beverage of excellence is definitively water, as this substance is more essential for life than food. Natural beverages for human consumption are divided into two main categories: (1) alcoholic beverages, mainly comprising wine, beer, and beverages with ethyl alcohol content; and (2) nonalcoholic beverages, which are distinguishable in the forms of water (drinking, mineral, and table), nervine beverages (coffee, tea, chamomile, etc.), and soft beverages (soft drinks, juices, and syrups). Two major categories of alcoholic beverages are commercially distinguishable: as low-gradation alcohols having ethyl alcohol quantities less than 21% by volume (beer or wine), and spirits, obtained from the distillation of fermented beverages (e.g., brandy from wine), having alcohol contents greater than 21% by volume.

Ultrasound is composed of mechanical sound waves that originate from molecular movements that oscillate in a propagation medium. The waves have a very high frequency, equal to approximately 20 kHz, are divided into two categories (i.e., low-intensity and high-intensity waves) and cannot be perceived by the human ear. Nature has created the first ultrasound applications. Bats use ultrasound to navigate in the dark, and many cetaceans use echolocation to detect prey or obstacles using ultrasound produced by their vocal system. Ultrasound is commonly associated with the biomedical field. Today, ultrasound-based methods and equipment are available to detect organs, motion, tumour masses, and pre/post-natal handicaps, and for kidney stone removal, physiotherapy, and aesthetic cures. However, ultrasound has found multiple applications in many other fields as well. In particular, ultrasound has recently been used in the food industry to develop various effective and reliable food processing applications. Therefore, this review summarizes the major applications of ultrasound in the food industry. The most common applications in the food industry include cell destruction and extraction of intracellular material. Depending on its intensity, ultrasound is used for the activation or deactivation of enzymes, mixing and homogenization, emulsification, dispersion, preservation, stabilization, dissolution and crystallization, hydrogenation, tenderization of meat, ripening, ageing and oxidation, and as an adjuvant for solid-liquid extraction for maceration to accelerate and to improve the extraction of active ingredients from different matrices, as well as the degassing and atomization of food preparations.

Chicken eggs represent a relevant diet source of cholesterol. With the aim of evaluating the cholesterol content of the eggs from Campania Region (Italy) and to test a new analytical procedure, a sample of 100 chicken eggs from local market was analysed by gas chromatography using a polar capillary column. The total free cholesterol was extracted from the egg yolk with n -hexane and trichloroacetic acid, and analysed without the saponification step commonly used. This alternative procedure was compared with the official method. The results indicate that the total free cholesterol content is in the range of 120–193 mg/egg (average value 157 ± 3 mg/egg) lower than the previously reported value of 213 mg/egg. The total free cholesterol quantity is not related to the yolk weight. The bound cholesterol contribution to the total cholesterol was negligible. Dietary recommendations aimed at restricting the egg consumption should be taken with caution and should not include all individuals.

BACKGROUND: Lycopene, a precursor of β-carotene with a well-known antioxidant activity, contained in many natural products such as tomato (Lycopersicon esculentum Mill.), watermelon, red pepper and papaya, is usually recovered from natural vegetal sources using organic solvents and a purification step. In this paper an innovative process for the extraction of pure lycopene from tomato waste in water that uses the Naviglio® extractor and water as extracting phase is presented. RESULTS: Lycopene was obtained in the all-trans form at a very high grade of purity, not less than 98% (w/w), with an average recovery of 14% (w/w). The availability of high-purity trans-lycopene allowed measurement of the molar absorption coefficient. An alternative procedure for high-performance liquid chromatographic analysis using a phenyl-hexyl silicone phase as inverse phase and a linear gradient in water and acetonitrile is also described. CONCLUSIONS: The use of water as extracting phase considerably reduces the cost of the entire process when compared with the commonly used solvent-based procedure or with the newer supercritical extraction process of lycopene from tomato waste. Lycopene, not soluble in water, was recovered in a quasi-crystalline solid form and purified by solid-phase extraction using a small amount of organic solvent. Copyright © 2008 Society of Chemical Industry This article was published online on September 15, 2008. Errors in Figures 2-4 were subsequently identified. The publishers wish to apologise for these errors. This notice is included in the online and print versions to indicate that both have been corrected [September 19, 2008]

Following the extraction of Castanea sativa with an aqueous solution of sulfuric acid (pH 3.0), the ethyl acetate soluble fraction was tested for its antibacterial and allelopathic activity. The extract was shown to have pronounced antibacterial effects against seven of the eight strains of Gram-positive and Gram-negative bacteria used (MIC in the range of 64-256 microg/ml and MBC in the range of 256-512 microg/ml). The active fraction was analyzed by TLC and HPLC showing the presence of rutin, hesperidin, quercetin, apigenin, morin, naringin, galangin and kaempferol. Standards of the identified flavonoids were tested against the same bacterial strains. The highest activity was shown by quercetin, rutin and apigenin. The allelopathic effect was tested against Raphanus sativus seed germination. The extract, quercetin, rutin and apigenin caused a decrease in the percentage of seed germination and root and epicotyl growth.