Search results for "Fruit"
showing 10 items of 859 documents
Changes of colour and carotenoids contents during high intensity pulsed electric field treatment in orange juices
2005
Abstract Liquid chromatography (LC) was the method chosen to evaluate the effects of high intensity pulsed electric fields (HIPEF), with different electric field intensities (25, 30, 35 and 40 kV/cm) and different treatment times (30–340 μs), on orange juice cis / trans carotenoid contents. In parallel, a conventional heat treatment (90 °C, 20 s) was applied to the orange juice in order to compare the effect on the carotenoid contents. HIPEF processing of orange juice is an alternative to the thermal treatment of pasteurization, provided that it is kept refrigerated, because, when the most extreme conditions of this kind of treatment are applied, the decrease in the concentration of caroten…
Comparison of stir bar sorptive extraction in the liquid and vapour phases, solvent-assisted flavour evaporation and headspace solid-phase microextra…
2017
The volatile fraction plays an important role on the organoleptic properties and overall acceptability of fruit juices. This work reports for first time a non-targeted approach for the analysis of the volatile fraction of fruit juice by stir bar sorptive extraction (SBSE[1]) in liquid and vapour phase (HSSE[2]) at three extraction times (30, 60, and 120 min), two temperatures (room temperature and 40 °C), and two sample volumes (5 and 10 mL). The resultant volatile profiles were compared with solvent-assisted flavour evaporation (SAFE[3]) and headspace solid-phase microextraction (HS-SPME[4]). SBSE and HSSE enabled the detection and identification of more compounds than HS-SPME and less tha…
Gas chromatographic evaluation of pesticide residue contents in nectarines after non-toxic washing treatments
2004
Washing with aqueous solutions of citric acid, ethanol, glycerol, hydrogen peroxide, potassium permanganate, sodium metabisulfite, sodium laurylsulfate (SLS), sodium hypochlorite, and urea is evaluated for pesticide residue reduction in nectarines and compared with simple tap water washing. Residues of pesticides commonly utilized in nectarines (chlorpyrifos, fenarimol, iprodione, malathion, methidathion, myclobutanil, parathion and pirimicarb) are extracted with ethyl acetate and anhydrous sodium sulfate, extract is concentred and analyzed by GC with nitrogen-phosphorus detection. The formation of possible toxic by-products (chlorpyrifos oxon, malaoxon, methidaoxon and paraoxon methyl) is …
Quality attributes of cactus pear fruit and their role in consumer choice
2015
Purpose – The purpose of this paper is to detect what experience and credence quality attributes contribute to the consumer decision to consume cactus pear fruit. The authors therefore try to measure the effect of each quality attribute on consumer choice. Design/methodology/approach – As a theoretical basis, two principal quality attributes emphasised in the literature on consumer behaviour were analysed and adjusted to the specific fruit features. The empirical strategy was carried out by administering a telephone questionnaire survey of 270 interviewees who consume cactus pears in Italy. The questionnaire, consisting of 14 items expressed on a metric scale (five-point Likert scale), was…
Physiological and Technical Aspects of Cactus Pear [Opuntia ficus-indica(L.) Mill.] Double Rellowering and Out-of-Season Winter Fruit Cropping
2007
Abstract A commercial cactus pear plantation in Sicily, Italy was manipulated to induce late cropping. The spring flush of flowers and cladodes were removed as was the second induced bloom of flowers and cladodes. The third induced bloom was harvested for a late out-of-season crop of cactus pear (Opuntia ficus-indica Mill.). The double removal induced a third flush of flowers and cladodes during late August with a fruit production that ripened the following winter (to March). The number of flowers per fertile cladode was halved after the double removal and the length of the fruit development period increased from 100-120 days to 160-190 days for the out-of-season crop. Polyethylene covering…
Full inhibition of enzymatic browning in the presence of thiol-functionalised silica nanomaterial
2018
[EN] Darkening processed fruits and vegetables is caused mainly by enzymatic browning through polyphenol oxidase (PPO) action. Accordingly, we explored the potential of four silica-based materials (MCM-41 nanometric size, MCM-41 micrometric size, UVM-7 and aerosil), non-functionalised and functionalised with thiol groups, to inhibit PPO activity in the model system and apple juice. All materials showed relevant performance when immobilising and inhibiting PPO in model systems, and support topology is a main factor for enzyme immobilisation and inhibition. Thiol-containing silica UVM7-SH showed the greatest inactivation, and similar browning values to those obtained by acidification. The enz…
Influence of the functionalisation of mesoporous silica material UVM-7 on polyphenol oxidase enzyme capture and enzymatic browning
2020
Polyphenol oxidase (PPO), also known as tyrosinase and catechol oxidase, is the enzyme responsible for enzymatic browning in foods. It causes undesirable organoleptic, nutritional and colour changes. Here, we report the preparation of five nanomaterials and a study of their ability to modulate PPO enzyme activity. The materials consist of UVM-7 supports (a mesoporous silica material) modified with diverse functional groups (i.e. amine, carboxylic acid, isocyanate, alkane and pyridine). We also studied the PPO immobilisation capability of the materials. All the materials, except the carboxylic acid functionalised one, offer high PPO loading capabilities and the immobilisation speed increases…
Impact on flavour release of the structure of composite gels containing polysaccharides: Example of the fruit préparations
2006
The main objective of this study was to understand the respective rôle of the structure of a food product and of the physicochemical interactions on flavour release. For that purpose, fruit préparations hâve been chosen as model matrices. Those matrices contain a polysaccharide as gelling agent, a cross-linked waxy corn starch (1.4%), a high sucrose content (35%), an acidic buffer and a strawberry aroma (17 molécules). Four matrices were developed by modifying either the composition or the concentration in gelling agent: two matrices of similar texture containing either LM pectin or carrageenan, and two carrageenan based matrices with différent gelled structures. In a first step; two comple…
The coast of Altavilla Milicai east of Palermo. Story of a forgotten coastal landscape between illegal building, architectural-landscape emergencies …
2017
La costa di Altavilla Milicia ad est di Palermo. Storia di un paesaggio costiero dimenticato fra edifici illegali, emergenze architettoniche-paesaggistiche e la necessità di protezione. La costa che va da Bagheria a Cefalù è caratterizzata dalla presenza di numerose costruzioni abusive che, in tantissimi casi sorgono sulla stessa battigia in dispregio a qualsiasi norma urbanistica. Questo fenomeno invasivo, in parte anche profdotto da pianoi regolatori urbanistici non curanti dei valori paesaggistici fortemente presenti in questa area, ha avuto inizio dagli anni settanta del Novecento, con la ricerca di seconde case per la residenza stagionale soprattutto da parte degli abitanti di Palermo.…
Evaluating free school fruit: results from a natural experiment in Norway with representative data
2014
AbstractObjectiveTo assess impacts of the nationwide Norwegian School Fruit Scheme (NSFS) using nationally representative data.DesignThe NSFS is organized such that primary-school children (grades 1–7) are randomly assigned to one of three school fruit arrangements: (i) the child receives one free fruit or vegetable per day; (ii) the child is given the option to subscribe to one fruit or vegetable per day at a subsidized price; and (iii) the child attends a school that has no school fruit arrangement.SettingData from an Internet survey are used to compare child and parental fruit and vegetable intakes across the three NSFS groups focusing mainly on groups (i) and (iii). The analysis was con…