‘Annurca’ apple fruit,a southern Italy apple cultivar: textural properties and aroma composition

‘Annurca’ apple fruit, which is commonly cultivated in southern Italy and undergoes a typical reddening treatment and, is notable for its high firmness and its characteristic flavour, was examined for its pectic and aroma composition. Pectin, extracted with a water solution of potassium oxalate and dimethylsulphoxide, was found to be quantitavely and qualitatively important for its contribution to the high tissue firmness. Pectin changes its composition during the reddening process and there is even a difference in the pectic composition of the two ‘Annurca’ clones examined in this paper, ‘Standard’ and ‘Rossa del Sud’. Volatile compounds were collected by headspace sampling of intact unreddened and reddened fruits. Thirty-one compounds of several chemical classes were identified, to establish their role in the characteristic flavor of this apple cv. Among these compounds, n-pentanol was unusually present in large amounts; also δ-octalactone, never found in apples, was present.     

Changes in structure and aroma release from starch–aroma systems upon α-amylase addition

The influence of starch hydrolysis by α-amylase addition on structural properties and aroma release from starch–aroma systems was studied. A food model system composed of aqueous tapioca starch dispersion (4 g dry starch/100 g dispersion) and one aroma compound (menthone) was investigated. Structure breakdown and related changes in starch fraction (amylose) were measured by rheology and iodine-binding. Menthone release from the aroma-starch system in the headspace was followed by proton transfer reaction-mass spectrometry (PTR-MS) upon starch hydrolysis. A slightly higher viscosity was found for the starch–menthone system compared to the starch system without menthone upon α-amylase addition. One could hypothesise that menthone acts as a kind of nucleation agent for inducing structure build-up of starch segments, hindering starch degradation. An extensive aroma release from aroma–starch systems upon α-amylase addition was expected, but, instead, just a slight volatile increase was found after a starch hydrolysis time of 60 min. It is suggested that aroma release is the result of several superimposed effects ranging from viscosity effects to interactions between aroma compounds and starch degradation products.     

The influence of beverages on the stimulation and viscoelasticity of saliva: Relationship to mouthfeel?

The viscoelasticity and secretion rate of stimulated saliva depends on food and beverage related stimuli, and it is demonstrated that this may subsequently influence the sensory properties and particularly the mouthfeel and afterfeel associated with the product being consumed. Using saliva donated by twelve volunteers, it is shown that acidic beverages such as peach flavoured iced tea and a fizzy cola stimulate significantly higher flow rates of whole mouth saliva that has greater elasticity in comparison to that generated following stimulation by water. In comparison, mechanical action from chewing flavourless gum and the stimulation from sucking a mint also stimulate high flow rates of saliva, although it is significantly less elastic than that from acid-based stimuli. However, the viscosity of human whole mouth saliva is relatively insensitive to beverage type, chewing, or mint. It is speculated that the stimulation of highly elastic saliva in response to acidic beverages is a defence mechanism for protecting the teeth from acid erosion. A separate sensory panel was used to identify key mouthfeel attributes that are likely to be related to the response of saliva, including: tongue dryness, mouth moistness, amount of saliva, tongue sensation, and throat drying. These results indicate that saliva viscoelasticity and flow rate alter dramatically in response to what a consumer eats and drinks, and that this in turn may affect mouthfeel and other organoleptic properties.     

Could non-Saccharomyces yeasts contribute on innovative brewing fermentations?

With the advances in the production of beer worldwide, more challenges arise each year in the search for new approaches to the development of distinctive beverages. Attempts to obtain products with more complex sensory characteristics have led experts and brewers to prospect for non-conventional yeasts, i.e., non-Saccharomyces yeasts that may provide a new range of perspectives in terms of techniques and approaches. Besides the widespread use of Dekkera/Brettanomyces for the production of sour beers, other species are emerging for presenting unusual metabolic features that include the production of fruity esters, and a distinctive enzymatic apparatus. Wickerhamomyces anomalus and Torulaspora delbrueckii stand out as the most promising yeasts in brewing processes. Such new tendencies in the use of non-Saccharomyces yeasts comprise the production of low-alcohol beers, functional beers, and bioflavoring approaches. This is a little explored field in brewing practice, still requiring extensive research with practical application. In this sense, this review aims to present the main points for the application of non-conventional yeasts in beer production, and thus contribute to future advances in the topic.     

Does it make sense to modify tropical cyclones? A decision-analytic assessment

Recent dramatic increases in damages caused by tropical cyclones (TCs) and improved understanding of TC physics have led DHS to fund research on intentional hurricane modification. We present a decision analytic assessment of whether it is potentially cost-effective to attempt to lower the wind speed of TCs approaching South Florida by reducing sea surface temperatures with wind-wave pumps. Using historical data on hurricanes approaching South Florida, we develop prior probabilities of how storms might evolve. The effects of modification are estimated using a modern TC model. The FEMA HAZUS-MH MR3 damage model and census data on the value of property at risk are used to estimate expected economic losses. We compare wind damages after storm modification with damages after implementing hardening strategies protecting buildings. We find that if it were feasible and properly implemented, modification could reduce net losses from an intense storm more than hardening structures. However, hardening provides "fail safe" protection for average storms that might not be achieved if the only option were modification. The effect of natural variability is larger than that of either strategy. Damage from storm surge is modest in the scenario studied but might be abated by modification.     

Could multiple low-affinity bonds mediate primary sperm-zona pellucida binding?

The current model for primary sperm binding to the zona pellucida is that a cell-surface sperm protein binds with high affinity in an order-specific manner to one of the zona pellucida proteins, ZP3. However, the molecular details of primary sperm-zona pellucida binding remain elusive. A possible revised model is that multiple low-affinity bonds between spermatozoa and the zona pellucida may be sufficient for primary binding. The avidity of several low-affinity bonds can exceed that of a single high-affinity bond, which is sufficient to tether a motile spermatozoon. A mechanism involving multiple low-affinity bonds could account for some of the difficulties in elucidating primary sperm-zona pellucida interactions.     

Could squalene be an added value to use olive by-products?

Squalene (SQ) is an intermediate hydrocarbon in the biosynthesis of phytosterols and terpenes in plants. It is widely used for applications such as skin moisturizers, vaccines, or in carriers for active lipophilic molecules. It has commonly been obtained from sharks, but restrictions on their use have created a need to find alternative sources. We present a review of studies concerning SQ in olive groves to characterize its content and to provide new aspects that may increase the circular economy of the olive tree. There is a large variation in SQ content in virgin olive oil due to cultivars and agronomic issues such as region, climate, types of soil, crop practices, and harvest date. Cultivars with the highest SQ content in their virgin olive oil were ‘Nocellara de Belice’, ‘Drobnica’, ‘Souri’, and ‘Oblica’. An interaction between cultivar and aspects such as irrigation practices or agricultural season is frequently observed. Likewise, the production of high SQ content needs precise control of fruit maturation. Leaves represent an interesting source, if its extraction and yield compensate for the expenses of their disposal. Supercritical carbon dioxide extraction from olive oil deodorizer distillates offers an opportunity to obtain high-purity SQ from this derivative. Exploiting SQ obtained from olive groves for the pharmaceutical or cosmetic industries poses new challenges and opportunities to add value and recycle by-products. © 2019 Society of Chemical Industry     

Modification of cotton fabrics with β-cyclodextrin derivative for aroma finishing

The unique structure of β-cyclodextrin to form inclusion complexes has led to important commercial applications in several areas such as the pharmaceutical, cosmetic, and flavour industries. In this research, β-cyclodextrin modified with monochlorotriazine (β-CD-MCT) was synthesised and applied as surface modification on cotton fabrics. The possibility of entrapping sandalwood oil as an aroma-finishing agent has been investigated. The Fourier transform infrared, tensile tests, and gas chromatography-mass spectroscopy measurements were used to investigate the effects of the treatment. It was found that β-CD-MCT can be fixed to cotton fabrics with the pad–dry–cure method at high temperature. No loss of tensile strength of the treated fabrics was found. The fragrance disappeared from untreated cotton after 8 days when stored at ambient temperature (30°C). The fragrance was retained in β-CD-MCT-treated cotton fabrics for 21 days in the same conditions.     

Influence of the slicing technique on mechanical properties of?the?produced veneer

The aim of this investigation was to compare the mechanical behaviour of lengthwise and plain sliced veneer of the species beech (Fagus sylvatica L.). Therefore, tension tests parallel and perpendicular to the grain were carried out. The results were evaluated using the variance analysis (ANOVA). As a result it can be stated that lengthwise sliced veneers exhibit significantly higher strength and better mechanical characteristics than plain sliced veneers. The checks parallel to the grain which occurred by manufacturing at that side of the veneer leaf which faces the cutting edge and which is stressed in tension are to be considered as reason therefore. In contrast to the tests parallel to the grain the modulus of elasticity perpendicular to the grain shows significantly lower values for lengthwise sliced veneers than for plain sliced veneers. Due to their higher strength values lengthwise sliced veneers are considered better base materials for engineered wood products than plain sliced veneers.     

Could hop-derived bitter compounds improve glucose homeostasis by stimulating the secretion of GLP-1?

Hops (Humulus lupulus L.) is by far the greatest contributors to the bitter property of beer. Over the past years, a large body of evidence demonstrated the presence of taste receptors in different locations of the oral cavity. In addition to the taste buds of the tongue, cells expressing these receptors have been identified in olfactory bulbs, respiratory and gastrointestinal tract. In the gut, the attention was mainly directed to sweet Taste Receptor (T1R) and bitter Taste Receptor (T2R) receptors. In particular, T2R has shown to modulate secretion of different gut hormones, mainly Glucagon-like Peptide 1 (GLP-1), which are involved in the regulation of glucose homeostasis and the control of gut motility, thereby increasing the sense of satiety. Scientific interest in the activity of bitter taste receptors emerges because of their wide distribution in the human species and the large range of natural substances that interact with them. Beer, whose alcohol content is lower than in other common alcoholic beverages, contains a considerable amount of bitter compounds and current scientific evidence shows a direct effect of beer compounds on glucose homeostasis. The purpose of this paper is to review the available literature data in order to substantiate the novel hypothesis of a possible direct effect of hop-derived bitter compounds on secretion of GLP-1, through the activation of T2R, with consequent improvement of glucose homeostasis.     

Does a time constraint modify results from rating-based conjoint analysis? Case study with orange/pomegranate juice bottles

People do not usually process all the available information on packages for making their food choices and rely on heuristics for making their decisions, particularly when having limited time. However, in most consumer studies encourage participants to invest a lot of time for making their choices. Therefore, imposing a time-constraint in consumer studies may increase their ecological validity. In this context, the aim of the present work was to evaluate the influence of a time-constraint on consumer evaluation of pomegranate/orange juice bottles using rating-based conjoint task. A consumer study with 100 participants was carried out, in which they had to evaluate 16 pomegranate/orange fruit juice bottles, differing in bottle design, front-of-pack nutritional information, nutrition claim and processing claim, and to rate their intention to purchase. Half of the participants evaluated the bottle images without time constraint and the other half had a time-constraint of 3 s for evaluating each image. Eye-movements were recorded during the evaluation. Results showed that time-constraint when evaluating intention to purchase did not largely modify the way in which consumers visually processed bottle images. Regardless of the experimental condition (with or without time constraint), they tended to evaluate the same product characteristics and to give them the same relative importance. However, a trend towards a more superficial evaluation of the bottles that skipped complex information was observed. Regarding the influence of product characteristics on consumer intention to purchase, bottle design was the variable with the largest relative importance in both conditions, overriding the influence of nutritional or processing characteristics, which stresses the importance of graphic design in shaping consumer perception.     

Global grape aroma potential and its individual analysis by SBSE–GC–MS

Among the aroma compounds present within grapes, a significant part is assumed to come from specific odourless precursors found mainly as glycosidic compounds which are known as bound fraction. In this paper, the individual composition of non-aromatic red grape bound fraction has been assayed for first time by SBSE–GC–MS and compared with the global total aroma potential measured spectrophotometrically at the wineries, in which the anthocyanins interferences have been removed. Glycosidic aroma compounds have been extracted by macerating grapes with different extractants (EtOH_aq or SO₂) at different times and subjected to acidic hydrolysis at 70 °C for 2 h. The best extraction condition, expressed as the higher aroma compounds concentration (terpenes + C₁₃ norisoprenoids + 2-phenylethanol + C₆ compounds), was the ethanolic aqueous extraction carried out for 2 h, reducing considerably the extraction times proposed in the literature. The method was successfully used to discriminate non-aromatic red grape varieties, (Petit-Verdot, Merlot and Monastrell) being limonene, linalool, 2-hexen-1-ol, TDN and 2-phenylethanol the aromas that contributed most to the differentiation. An aromatic white table grape such as Early sugar was also assayed to check its higher volatile composition in comparison with the other red varieties. The percentage of favourable aromas (terpenes + C₁₃ norisoprensoids + bencene derivates) is always higher than the unfavourable ones (C6) for all tested varieties, especially Early Sugar. It has also been observe that the spectrophotometric measurements are overestimated when compared with SBSE–GC–MS, probably due to the free sugar content and other glycosidic compounds.     

Characterization of the differences in the aroma of cherry wines from different price segments using gas chromatography–mass spectrometry,odor activity values,sensory analysis,and aroma reconstitution

The aroma composition, aroma-active compounds, and sensory attributions of cherry wines from three different price segments were investigated. A total of 48 aroma compounds were identified and quantified using headspace solid-phase microextraction (HS-SPME)/gas chromatography–mass spectrometry (GC–MS), among which 23 aroma compounds were further screened out as important odorants based on their odor activity values (OAVs); then, the previously mentioned 23 volatiles were correlated to sensory attributes using partial least-squares regression (PLSR). The result indicates that the differently priced wines were associated with different compounds and aroma attributions. Finally, aroma reconstitution was performed by mixing odor-active aroma compounds (OAVs>1) on the basis of their measured concentrations in the original sample. The result indicated that the aroma profile of the reconstituted sample was similar to that of the original sample.     

Could telehealth help eye care practitioners adapt contact lens services during the COVID-19 pandemic?

The COVID-19 pandemic has necessitated government-imposed restrictions on social interactions and travel. For many, the guidance has led to new ways of working, most notably a shift towards working remotely. While eye care practitioners (ECPs) may continue to provide urgent or emergency eye care, in many cases the travel restrictions present a unique challenge by preventing conventional face-to-face examination. Telephone triage provides a useful starting point for establishing at-risk and emergency patients; but patient examination is central to contact lens patient care.The indeterminate period over which conventional practice will be suspended, and the risk that resumption of ‘normal’ practice could be impeded by a potential secondary peak in COVID-19 cases, hastens the need for practitioners to adapt their delivery of eyecare. Specifically, it is prudent to reflect upon supportive evidence for more comprehensive approaches to teleoptometry in contact lens practice.Smartphone based ocular imaging is an area which has seen considerable growth, particularly for imaging the posterior eye. Smartphone imaging of the anterior eye requires additional specialised instrumentation unlikely to be available to patients at home. Further, there is only limited evidence for self-administered image capture. In general, digital photographs, are useful for detection of gross anterior eye changes, but subtle changes are less discernible.For the assessment of visual acuity, many electronic test charts have been validated for use by practitioners. Research into self-administered visual acuity measures remains limited.The absence of a comprehensive evidence base for teleoptometry limits ECPs, particularly during this pandemic. Knowledge gaps ought to be addressed to facilitate development of optometry specific evidence-based guidance for telecare. In particular, advances in ocular self-imaging could help move this field forwards.     

Producing headspace extracts for the gas chromatography–olfactometric evaluation of wine aroma

In this work different designs of headspace devices were studied. Using these designs, 23 volatile compounds of wine aroma added to a synthetic wine were purged by an inert gas (nitrogen) and trapped in a solid-phase extraction (SPE) cartridge. Efficiency was measured as the similarity between the odour intensity in a model wine in the glass and the odour intensity recorded in the gas chromatography–olfactometry (GC–O) experiment.     

How does infiltration behavior modify the composition of ambient PM2.5 in indoor spaces? An analysis of RIOPA data

The indoor environment is an important venue for exposure to fine particulate matter (PM2.5) of ambient (outdoor) origin. In this work, paired indoor and outdoor PM2.5 species concentrations from three geographically distinct cities (Houston, TX, Los Angeles County, CA, and Elizabeth, NJ) were analyzed using positive matrix factorization (PMF) and demonstrate that the composition and source contributions of ambient PM2.5 are substantially modified by outdoor-to-indoor transport. Our results suggest that predictions of "indoor PM2.5 of ambient origin" are improved when ambient PM2.5 is treated as a combination of four distinct particle types with differing infiltration behavior (primary combustion, secondary sulfate and organics, secondary nitrate, and mechanically generated PM) rather than as a "single internally mixed entity". Study-wide average infiltration factors (i.e., fraction of ambient PM2.5 found indoors) for Relationship of Indoor, Outdoor, and Personal Air (RIOPA) study homes were 0.51, 0.78, and 0.04 (consistent with P = 0.6, 0.9, and 0.09; k = 0.2, 0.1, and 0.6 h(-1)) for PM2.5 associated with primary combustion, secondary formation (excluding nitrate), and mechanical generation, respectively. Modification of the composition, properties, and source contributions of ambient PM2.5 in indoor environments has important implications for exposure mitigation strategies, development of health hypotheses, and evaluation of exposure error in epidemiological studies that use ambient central-site PM2.5 as a surrogate for PM2.5 exposure.     

Could the Dumas Method Replace the Kjeldahl Digestion for Nitrogen and Crude Protein Determinations in Foods?

Increased demand for determinations of nitrogen (N), and hence crude protein (CP), has led to wider use of the Dumas method in place of the traditional Kjeldahl methods. Although Kjeldahl N (KN) and Dumas N (DN) represent different N fractions, published studies on infant formula, animal feed and meat products have indicated that DN could replace KN with little practical impact on the reliability of the N values obtained. This study was conducted to establish whether DN determination could replace that of KN in a broader range of foods for CP calculation. Statistical analysis was performed on in-house assayed KN and DN values together with published KN and DN values for selected food products. In the range 0·05–6·8% N, KN may be estimated from DN with the equation: KN=1·00^(P<0·01)×DN-0·09^(P=0·50) (n=101, R²=0·98, P-regression<0·01). Because N levels in individual groups of food did not span the entire range of N contents, KN: DN ratios were calculated for each food group. KN: DN ratios differed significantly (R²=0·25, P<0·01) from group to group. Ratios of 1·01 for dairy, 1·00 for oilseeds, 0·99 for feed, 0·98 for infant formulas, 0·95 for cereals, 0·94 for meats, 0·89 for vegetables, 0·80 for fish and 0·73 for fruits were valid for the estimation of KN and CP using DN data. CP was independently calculated as CP1=H×KN or CP2=H×KN: DN×DN, where H is the nitrogen to protein conversion factor for the food group. Mean differences between CP1 and CP2 values were 0% for dairy, oilseeds, feed, infant formulas and baby foods, cereals, meat and meat products, vegetables and vegetable products and fruit, and 1% for fish. These results suggest that DN may replace KN for the determination of N and CP in selected food groups when appropriate coefficients are used. © 1997 SCI.     

Effect of the structure of monoglyceride–oil–water gels on aroma partition

The aim of the present research was to study the aroma partition properties of saturated monoglyceride–oil–water gels. To this purpose, gels added with lemon oil were prepared mixing water, sunflower oil and commercial saturated monoglycerides. Three mixtures containing different ratios between the ingredients were considered. The gel characteristics were studied by synchrotron X-ray diffraction (XRD), calorimetry, polarized light microscopy and rheological measurements. The aroma partition was studied by using HSGC analysis.The gel structure is made of a multilamellar crystalline network, in which monoglycerides form shells encapsulating oil. Depending on the ratio between ingredients, the gel shows different rheological behaviour. The structured multilamellar phases greatly affect the partition of aroma evidencing the capability to entrap lipophilic compounds within the monoglyceride/oil shells. Since the aroma entrapping capacity showed by monoglyceride structures could greatly affect the perceived aroma intensity of the final product, this effect should be carefully taken into account during the development of new formulations.     

Bending properties of compressed wood impregnated with?phenolic resin through drilled holes

The effect of drilling on the permeability of Japanese cedar and the bending properties of resin treated compressed wood were examined. Compressed wood was manufactured by impregnating aqueous phenolic resin solutions into the heartwood through drilled holes and polymerizing the impregnated resins using a hot press to maintain the deformation. The compressive deformation was carried out at 150°C for 1 h to one-half of the original specimen thickness. A dye solution permeated the entire specimen when the density of drilled holes exceeded approximately 5000?holes/m². When the compressed wood was manufactured under the drilling condition, the resin type was found to greatly affect the bending strength and the failure mode of the specimens in bending test.