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1.

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.  相似文献   
2.
A CONTENT ANALYSIS OF SELF-DESCRIPTIVE ESSAYS WRITTEN BY STUDENTS 13 OF WHOM WERE SUBSEQUENTLY SUCCESSFUL AND 11 UNSUCCESSFUL SS IN ATTAINING SELF-DIRECTED BEHAVIOR-CHANGE GOALS REVEALED: (1) HIGH-CHANGE SS MORE FREQUENTLY STATED GOALS, WITH IMPLICIT RECOGNITION THAT THE GOAL HAD NOT YET BEEN ATTAINED; (2) LOW-CHANGE SS MORE FREQUENTLY DESCRIBED THEMSELVES WITH LITTLE RECOGNITION OF ALTERNATIVE POSSIBILITIES, AND (3) LOW-CHANGE SS SHOWED MORE TENTATIVENESS AND UNCERTAINTY ABOUT THEMSELVES (IDENTITY DIFFUSION). THE FINDINGS WERE CROSS-VALIDATED IN A 2ND SAMPLE OF 9 SUCCESSFUL AND 22 UNSUCCESSFUL SS. RESULTS SUGGEST THAT SUCCESSFUL SELF-DIRECTED CHANGE IS MOTIVATED BY AWARENESS OF THE COGNITIVE DISSONANCE CREATED WHEN AN INDIVIDUAL COMMITS HIMSELF TO A VALUED GOAL THAT HE SEES AS DIFFERENT FROM HIS PRESENT BEHAVIOR. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
The rate of paste hydration of 3CaO·SiO2 (C3S) and the effects of additions of CaCl2, CdI2, and CrCl3, were studied by differential thermal analysis and thermogravimetry. X-ray analyses were used to identify the synthesized C3S. The salts CaCl2, CdI2, and CrCl3, accelerated the hydration of C3S. The degree of hydration was estimated by the amount of Ca(OH)2, formed, as determined by TG.  相似文献   
4.
碳纳米管/热致液晶复合材料的研究进展   总被引:2,自引:2,他引:0  
碳纳米管/聚合物复合材料是当代碳纳米管研究领域的前沿课题,也是一项多学科交叉、多技术集成的系统工程。由于液晶和碳纳米管的特殊性能和在光电领域的潜在应用,碳纳米管液晶复合体系已经引起人们的广泛关注。本文简单介绍了近年来碳纳米管/热致液晶复合材料的发展状况,阐述了其制备原理、工艺方法、存在的问题及潜在的应用领域。  相似文献   
5.

ABSTRACT

Sensory evaluation was used to determine the aroma threshold of Harmonia axyridis (multicolored Asian lady beetle [MALB]) in Concord grape juice. Prior to Concord grape juice preparation, MALB was added to the Concord grapes at concentrations of 0 and 8.4 MALB/kg fresh grapes. To determine the odor threshold, the three alternative forced‐choice method of sample presentation was used, with an ascending concentration series of 0.5, 1.5 and 4.5 MALB/kg fresh grapes. The panel aroma threshold concentration, calculated using the best estimate threshold over two panel sessions, was 1.8 MALB/kg fresh grapes. Individual detection thresholds ranged from 0.29 to 7.79 MALB/kg fresh grapes, with 75% of the panelists having a detection threshold at or below 0.87 MALB/kg fresh grapes. These results indicate the influence of low numbers of MALB on Concord grape juice aroma, and suggest the importance of quality control programs, including the implementation of established tolerance limits, to monitor grape quality.

PRACTICAL APPLICATIONS

Harmonia axyridis, the multicolored Asian Ladybeetle (MALB), was originally introduced as a method of biocontrol. However, its presence is now becoming problematic with respect to crop quality. In order to minimize economic losses to the Concord grape industry, determination of the number of MALB required to produce a detectable change in Concord grape juice is critical for juice producers in the establishment of their quality control programs. Therefore, the objective of this study was to determine the aroma threshold level of MALB in Concord grape juice. The panel aroma threshold concentration, calculated using the best estimate threshold was 1.8 MALB/kg fresh grapes, with 75% of the panelists having a detection threshold at or below 0.87 MALB/kg fresh grapes. These results indicate the influence of low numbers of MALB on Concord grape juice aroma, and suggest the importance of quality control programs, including the implementation of established tolerance limits, to monitor grape quality.
  相似文献   
6.
Quenching from high temperatures, supplemented by differential thermal analysis, has shown that the tungsten-carbon binary is characterized by eutectic temperatures of 2710° and 2760°C between W and W2C, and between W2C and a new high-temperature phase (β-WC), respectively. Carbon solubility in excess of stoichiometric W2C is evident only at 2525°C, the eutectoid temperature between W2C and WC. W2.35C melts congruently at 2795°C. A new fee phase (β-WC), stable only above 2525°, has been discovered between W2C and α-WC. The cubic phase is formed by a periteci reaction at approximately 2785°C and has a broad homogeneity range ear the solidus. The phase, α-WC, decomposes into β-WC and C at 2755°C, approximately 25°C below the melting temperature.  相似文献   
7.
The exposure of foods to the temperature and humidity needed to dry the coatings can have deleterious effects on their quality. A critical analysis of the film drying conditions on quality indexes for butternut squash slices is presented. During the coatings drying, the samples lost significant amounts of weight and ascorbic acid. Only during the drying of the chitosan coating for 100 min at 20C and for 30 min at 50C that the ascorbic acid contents were not significantly reduced. The application of casein and carboxy methyl cellulose coatings did not cause significant reductions in the counts of mesophilic aerobic microorganisms (5.75–6.00 Log CFU/g). Chitosan coated samples presented significant log reductions showing the higher reductions the samples dried for 30 min at 50C (5.02 Log CFU/g). For the preservation of the nutritional and microbiological quality indexes of squash slices, the best coating conditions would be chitosan dried for 30 min at 50C.

PRACTICAL APPLICATIONS


The continuous consumer interest in high quality and food safety, combined with environmental concern, has induced the development and study of new edible coatings that avoid the use of synthetic materials. The edible coatings, formed from Generally Recognized as Safe materials, have the potential to reduce weight loss, respiration rate and improve food appearance and integrity. It is one of the most effective methods to maintain food quality.
Antimicrobial films and coatings have innovated the concept of active packaging and have been developed to reduce, inhibit or delay the growth of microorganisms on the surface of food in contact with the packaged products. In addition, the edible coatings allow the incorporation of food additives with antimicrobial effects that might help reduce microbial spoilage during postharvest.  相似文献   
8.
Information on desiccation sensitivity of Euterpe edulis seeds under two drying rates is presented. The sensitivity was studied during the course of germination and normal germination. The water content was evaluated for both seeds and embryos. Results showed the following: (a) For both drying treatments and for both germination and normal germination, desiccation sensitivity values were higher for measurements based on the water content of the embryo than for those of the seed. (b) For both drying treatments, desiccation sensitivity were higher for normal germination than for germination based on both the embryo and seed water contents. (c) Under the slow drying treatment and for measurements based on the seed water content, critical water content was visible for normal germination but not for germination; (d) Critical water contents for germination and normal germination were more clearly established in the fast drying treatment than they were in the slow drying method based on both the embryo and seed water contents. Critical water contents were not associated with changes in electrolyte leakage, which suggests that conductivity is not a good indicator of physiological seed quality. From the beginning of both drying treatments, changes in nuclei and vacuoles were observed, but, when seed water content was reduced to below critical values, the cells became severely plasmolyzed, the vacuoles highly distorted, and the nuclei formed an almost homogeneous mass with the chromatin and the nucleoplasm, which suggests irreversible DNA damages.  相似文献   
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