Evaluation of peach and nectarine fruit quality and correlations between sensory and chemical attributes

Sensory attributes and chemical composition in peach and nectarine fruits of nine different cultivars were evaluated and compared. The cultivars investigated in the research were: ‘Maria Marta’, ‘Romestar’, ‘325 × A/8’, ‘224 × A/13’, ‘V × S/4’, ‘Bea’, ‘Maria Aurelia’, ‘Venus’ and ‘Spring Red’. In sensory evaluation the ‘Maria Aurelia’ was the highest rated, and the ‘224 × A/13’ was the lowest. The cultivars ‘325 × A/8’, ‘224 × A/13’, ‘V × S/4’ and ‘Spring Red’ were poor in sugars; however, the ‘Spring Red’ was rich in organic acids. Similarly, the ‘Maria Aurelia’ and ‘Venus’ fruits had higher contents of organic acids and were also rich in sugars. Furthermore, the relationships among sensory and chemical attributes of fruit quality were studied. The sensory evaluations of sweetness, taste, and aroma were well correlated with some chemically measured attributes of peach and nectarine quality: sweetness was influenced by citric acid, shikimic acid and sugars/organic acids ratio; aroma was correlated with total organic acids, sucrose, sorbitol and malic acid; taste was related to malic/citric acid ratio, total sugars, sucrose, sorbitol and malic acid. The results of the research indicate that sensory evaluation provides a good tool in the quick assessment of peach and nectarine fruit quality. Copyright © 2005 Society of Chemical Industry     

Relevance for food sciences of quantitative spatially resolved element profile investigations in wheat (Triticum aestivum) grain

Bulk element concentrations of whole grain and element spatial distributions at the tissue level were investigated in wheat (Triticum aestivum) grain grown in Zn-enriched soil. Inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry were used for bulk analysis, whereas micro-proton-induced X-ray emission was used to resolve the two-dimensional localization of the elements. Soil Zn application did not significantly affect the grain yield, but did significantly increase the grain Ca, Fe and Zn concentrations, and decrease the grain Na, P and Mo concentrations; bulk Mg, S, K, Mn, Cu, Cd and Pb concentrations remained unchanged. These changes observed in bulk element concentrations are the reflection of tissue-specific variations within the grain, revealing that Zn application to soil can lead to considerable alterations in the element distributions within the grain, which might ultimately influence the quality of the milling fractions. Spatially resolved investigations into the partitioning of the element concentrations identified the tissues with the highest element concentrations, which is of utmost importance for accurate prediction of element losses during the grain milling and polishing processes.     

Parameter optimization for the enzymatic hydrolysis of sunflower oil in high-pressure reactors

This study is concerned with the hydrolysis of sunflower oil in the presence of lipase preparation Lipolase 100T (Aspergillus niger lipase). Supercritical carbon dioxide was used as a solvent for this reaction. In a high-pressure stirred tank reactor operated in a batch mode, the effects of various process parameters (temperature, pressure, enzyme/substrate ratio, pH, and oil/buffer ratio) were investigated to determine the optimal reaction rate and conversion for the hydrolysis process. The optimal concentration of lipase was 0.0714 g/mL of CO₂-free reaction mixture, and the highest conversions of oleic acid (0.193 g/g of oil phase) and linoleic acid (0.586 g/g of oil phase) were obtained at 50°C, 200 bar, pH=7, and an oil/buffer ratio of 1∶1 (w/w).     

Effects of controlled nucleation on freeze-drying lactose and mannitol aqueous solutions

The lyophilization of lactose and mannitol aqueous solutions was investigated with an emphasis on analyzing the effects of controlled nucleation, temperature of nucleation, and pore size distribution on the freeze-drying process. The experimental procedure involved the depressurization technique of controlled nucleation, in-vial temperature measurements as well as measurements of the chamber pressure, which allowed the analysis of the product batch, loaded in the laboratory lyophilizator. The average pore enlargement was 93 and 58% with the incorporation of the controlled nucleation step in the lyophilization of 6?wt% lactose and 6?wt% mannitol solutions, respectively. Consequently, the primary drying times were lowered from 450 to 500?min in both cases. The pore sizes were determined to be as important as the solid material itself in the scope of the sublimation rates. Namely, the average equivalent diameter of the pores was larger in the dried mannitol cake compared to the lactose cake. However, despite the higher porosity of the dried mannitol cake, the end of the sublimation in the primary drying step was observed approximately 500?min earlier during the lyophilization of the lactose solution with the same initial concentration as the mannitol solution in a comparable freeze-drying protocol. In addition, an increase in mannitol concentration from 3 to 12?wt% was found to substantially extend the time required for the sublimation phase of the lyophilization.     

Modeling of kinetics for the enzymatic hydrolysis of sunflower oil in a high-pressure reactor

This study presents a mathematical model for characterizing the Michaelis-Menten type of sunflower oil hydrolysis, catalyzed by the lipase preparation Lipolase 100T (Novozymes Ays, Bagsvaerd, Denmark). Supercritical carbon dioxide was used as a solvent for this reaction. Computer modeling of the kinetics was done for the enzymatic hydrolysis of sunflower oil in a high-pressure reactor using the MicroMath Scientist^® program (Micro-Math Research, St. Louis, MO). On the basis of the experimental results, we presumed the reaction was reversible. The suitability of the model was confirmed statistically with Student's t-test. Good agreement was found between the experimental and calculated values for the concentrations of oleic and linoleic acids.     

Distribution of selenium and phenolics in buckwheat plants grown from seeds soaked in Se solution and under different levels of UV-B radiation

Seeds of common buckwheat (Fagopyrum esculentum) were soaked in water, sodium selenate (5, 10 or 20 mg Se^VI/L), or sodium selenite (10 or 20 mg Se^IV/L) solutions. Plants grown from soaked seeds were exposed to reduced UV-B radiation, ambient, or enhanced UV-B. The mass fraction of selenium in leaves was much higher in plants obtained from seeds soaked with selenate (up to 185 ng/g) in comparison to selenite (up to 103 ng/g). In plants obtained from seeds soaked in water, regardless of UV-B levels, the highest concentration of selenium was found in leaves, where the values were between 45 and 66 ng Se/g. In buckwheat leaves 44.5–63.6 mg/100 g d.m. of fagopyrin was found, and in stems 14.3–26.4 mg/100 g d.m.; here no influence of seed soaking solution or UV-B exposure was found. The content of total flavonoids in leaves was 7.8–15.9% and in stems 1.4–4.1%.     

On Automating Diagrammatic Proofs of Arithmetic Arguments

Theorems in automated theorem proving are usually proved by formal logical proofs. However, there is a subset of problems which humans can prove by the use of geometric operations on diagrams, so called diagrammatic proofs. Insight is often more clearly perceived in these proofs than in the corresponding algebraic proofs; they capture an intuitive notion of truthfulness that humans find easy to see and understand. We are investigating and automating such diagrammatic reasoning about mathematical theorems. Concrete, rather than general diagrams are used to prove particular concrete instances of the universally quantified theorem. The diagrammatic proof is captured by the use of geometric operations on the diagram. These operations are the inference steps of the proof. An abstracted schematic proof of the universally quantified theorem is induced from these proof instances. The constructive -rule provides the mathematical basis for this step from schematic proofs to theoremhood. In this way we avoid the difficulty of treating a general case in a diagram. One method of confirming that the abstraction of the schematic proof from the proof instances is sound is proving the correctness of schematic proofs in the meta-theory of diagrams. These ideas have been implemented in the system, called Diamond, which is presented here.     

Preservative Efficacy Screening of Pharmaceutical Formulations Using ATP Bioluminescence

The preservative challenge test is a method used to determine the efficacy of a preservation system in a pharmaceutical or cosmetic formulation. However, such testing is a labor-intensive, repetitive task often requiring days before results can be generated. Several alternatives to traditional colony-count techniques have been developed. A study using pure suspensions of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, Candida albicans, and Aspergillus niger showed that the accuracy, repeatability, and linearity of the Pallchek? luminometer ATP bioluminescence (ATP-B) system was equivalent to the traditional colony-count method. In any case, the method proved sensitive enough to follow the effect of preservatives on a number of test microorganisms, indicating the applicability of the ATP-B method for preservative screening studies in various pharmaceutical formulations.     

User-centred app design for speech sound disorders interventions with tablet computers

Traditional speech and language pathology practice (SLPP) faces challenges delivering effective and timely therapy due to long waiting lists, the need for regular practice outside the clinic and a lack of children’s motivation to engage in persistent practice. Technology has untapped potential to address these issues and improve SLPP. This paper describes the design of a tablet app for delivering technology-enhanced therapy for children with speech sound disorders and investigates the impact of the use of apps on SLPP. The initial design was informed by a nation-wide survey of speech-language pathologists (SLPs). The quantitative analysis disclosed that even though SLPs positively perceive mobile technology, they do not currently fully exploit it in their practice due to a lack of apps in their native language and the limited usefulness of apps in foreign languages. Using a user-centred design process, a multidisciplinary team created three prototypes and a final version of an app that has been tested in real therapeutic sessions during everyday practice and informed by feedback from SLPs and children. The observation analysis is presented based on an adaptation of Koole’s FRAME model. The qualitative findings indicate that SLPs identify mobile apps as enabling greater mobility, allowing new therapeutic approaches, creating possibilities for practice outside the therapeutic setting and increasing children’s motivation, supporting greater persistence to practise in the context of the therapy.