NUTRITIONAL AND SENSORY SURVEY OF CITRUS SINENSIS (L.) CULTIVARS GROWN AT THE MOST NORTHERN LIMIT OF THE MEDITERRANEAN LATITUDE

ABSTRACT

This report describes Citrus sinensis fruit grown in the Lake Maggiore area (Italy), the upmost Northern distribution range of the genus Citrus in Europe. Total ascorbic acid (TAA), bioflavonoids, total polyphenol content (TPC), antioxidant activity, total soluble solid, total acidity and sensory characteristics were evaluated on oranges harvested during the 2009–2010 season. The range of values detected was as follows: TAA from 36.89 to 67.34 mg/100 mL, hesperidin from 18.97 to 31.87 mg/100 mL, narirutin from 17.30 to 29.28 mg/100 mL and rutin from 4.39 to 5.36 mg/100 mL; antioxidant activity (ferric reducing antioxidant power assay) from 8.62 to 17.00 mmol Fe²⁺/kg, fresh fruit weight; TPC (Folin–Ciocalteu method) from 87.16 to 135.16 mg GAE/100 g. This first attempt to characterize cultivars grown in the Piedmont region showed that these oranges had acceptable nutritional components and sensory quality, if compared with bibliographic data about cultivars grown in the subtropical and Mediterranean area.

PRACTICAL APPLICATIONS

The identification, characterization and valorization of old cultivars are essential to avoid loss of potentially useful germplasm. The reduction of biodiversity of cultivars found in agriculture could lead to problems such as higher susceptibility to widespread outbreaks of plant diseases and pests, and at the same time, the loss of precious source of nutrients. This survey was carried out to characterize a germplasm that could also be used in breeding programs to obtain new cold‐tolerant varieties.     

THE USE OF RHEOLOGY TO CHARACTERIZE FLOW BEHAVIOR OF LIQUORICE SOLUTIONS

The rheological behavior of liquorice solutions at different concentrations (ranging between 30 and 60 Brix) and temperatures (in the range between 25 and 80C) has been investigated performing both dynamic tests in the linear viscoelastic region and steady shear tests, in 0.1–100 s^?1 shear rate range, by using a stress controlled rheometer (DSR 200, Rheometric Scientific, USA) and parallel plate geometry (φ = 40 mm). Small amplitude oscillations has shown the presence of both moduli also at the lowest tested concentration, with G′ greater than G″, except for the 30 Brix sample. It has been found that experimental viscosity data show a good agreement with a power law model, thus allowing the estimation of both the friction factor and the pressure drops in a typical pipeline used for liquorice solution conveying. It has been observed that the assumption of Newtonian behavior can lead to the erroneous design of the apparatuses that have to process liquorice extracts.     

Absorption of Aroma Volatiles of Orange Juice into Laminated Carton Packages Did Not Affect Sensory Quality

Orange juice was stored in glass bottles and polyethylene/barrier material laminated cartons at 4°C for 24 wk. Studies were carried out on the absorption of 19 orange juice aroma compounds (e.g ethyl butyr-ate, d-limonene) into low density polyethylene (LDPE). Sensory evaluations were performed on the same orange juice in different packages over the storage period. A reduction of d-limonene of up to 50% by absorption into the LDPE inside coating was observed. However, an experienced sensory panel did not distinguish between orange juice stored in glass bottles and polyethylene laminated cartons.     

Solid Solubility and Polymorphism in the System Sr2SiO4-Sr2GeO4-Ba2GeO4-Ba2SiO4

The reciprocal salt pair Sr₂SiO₄-Sr₂GeO₄-Ba₂GeO₄-Ba₂SiO₄ was investigated using X-ray powder diffraction and DTA. Unlimited solubility in the low-K₂SO₄ structure type (α') occurs throughout the system above 85°C. The nonlinear changes of some lattice constants of the solid solutions are discussed. A stable monoclinic low-temperature (β) form of Sr₂SiO₄ was found which converts reversibly to the high-temperature α'-modification at 85°C. The enthalpy of the β-α' transition is 51 cal/mol. In the reciprocal salt pair the β-form solid solutions occur in a very narrow region below 85°C.     

The Role of Ammonia Adspecies on the Pathways of Catalytic Transformation at Mixed Metal Oxide Surfaces

Heterogeneous catalysis plays a central role in most chemical reactions of industrial importance [1], but new advanced catalysts (superselective, able to transform new feedstocks and to synthesize new products, etc.) are required to comply with the future energy, safety, health, and environmental needs of the chemical industry [2]. The design of these new catalytic materials requires further understanding of the surface processes determining the catalytic transformations [3].     

INTEGRATED KNOWLEDGE ACQUISITION FROM TEXT,PREVIOUSLY SOLVED CASES,AND EXPERT MEMORIES

Within the model-based knowledge engineering framework, an integrated knowledge acquisition method was developed for a complex real-world domain with different traces of expertise. By having an expert constructively explain the previously solved cases with more general information from other traces of expertise ( text, expert memories) a model-centered knowledge base is constructed. The proposed method allows for an early knowledge verification where the relevance, sufficiency, redundancy, and consistency of knowledge are already assessed at an informal level The early knowledge verification efficiently prepares the consecutive knowledge formalization. Through a cognitively adequate model of expertise and the explanation-oriented knowledge elicitation procedures, user-friendly second-generation expert systems may be developed.     

RECURSIVE MULTIDIMENSIONAL INTEGRATION

This article introduces quadtree and octree like methods to numerical integration. Four recursive and auto-adaptive algorithms are presented: one for two-dimensional integrals over a triangular region, one for two-dimensional integrals over a quadrilateral region, one for three-dimensional integrals over a tetrahedral region and one for three-dimensional integrals over a cubic region. The algorithms have been proven to work fast. © 1997 John Wiley & Sons, Ltd.     

Free Fatty Acids from Orange Juice Absorption into Laminated Cartons and their Effects on Adhesion

Orange juice was stored in polyethylene/aluminum foil laminated cartons at 8°C room temperature (RT), 35°C, and 55°C for up to 1 yr. Studies were carried out on the formation of 6 major free fatty acids (FFAs) in orange juice and their absorption into packaging materials during storage. Simultaneously adhesion tests on packaging materials were performed. Depending on storage temperature FFA concentrations increased steadily during storage and they were absorbed (in parallel) into the food contact layer of the packaging materials. Delamination between the plastic layer and aluminum foil occurred when a critical absorption level of 4–5 mg/dm² packaging material (corresponding to a level of 10.5–13.2 mg/cm³ or 1.1–1.4% in the inside polymer layer) was exceeded.