1,721,012 research outputs found
Protective action of lemongrass essential oil on mucilage from chia (Salvia hispanica) seeds
Full text linkMucilage extracted from chia seeds (Salvia hispanica) is reckoning an increasing interest for its mechanical and nutritional properties. Freeze-dried mucilage dispersed in solvent undergoes degradation, through autoxidation phenomena, that results in the loss of the initial rheological characteristics. In order to limit the extent of depolymerization, an essential oil (lemongrass essential oil, LEO) is here emulsified with chia mucilage (CM) suspensions, and the rheological behavior of samples containing LEO or not compared. Flow curves of CM suspensions and of CM emulsions dispersing LEO (O/W-CM) demonstrated that both the systems can be classified as plastic fluids, and that during storage a general decrease of the viscosity of CM suspensions is detected, while the viscosity of the O/W-CM systems remaining constant. The differences between the two systems were also confirmed by oscillatory tests and through measurements of intrinsic viscosity. By means of an accelerated oxidative test, it was unveiled that the short-term stability of CM suspensions is attributable to the reaction of oxidation, and that the presence of LEO, due to its anti-oxidative properties, allowed for preventing degradation phenomena on the chia mucilage. We conclude that the colloidal stability of chia-based mixtures can definitely be improved following to LEO treatment - hence forming an emulsion - thereby preventing short-term polymer degradation
Influence of Storage Conditions on Cholesterol Oxidation in Dried Egg Pasta
No full textThe oxidative characteristics of three different egg coproducts, namely, pasteurized eggs obtained from hens bred with organic methods (POE), pasteurized eggs from conventional breeding (PCE)
and pasteurized spray-dried eggs (SPCE) obtained from conventional breeding, were analyzed. SPCE samples showed the highest content of peroxide (PV) and cholesterol oxides (COPs). In
contrast, pasteurized eggs from organic breeding had the lowest index of oxidation. The three egg coproducts were used to produce dried egg pasta (spaghetti). The spaghetti was stored for 12 months at room temperature using typical pasta packaging (polypropylene foil) both under light, typical of retail conditions, and in the dark. Peroxide values and cholesterol oxidation were
monitored at time 0 and then quarterly for 12 months. The oxidative parameters were significantly different in various egg coproducts, but the peroxide values of pasta were in the range of 3.0-3.5 mequiv of O2/kg of fat, with no differences in the types of pasta prepared with the various egg coproducts. Samples stored in the dark did not show any significant variations in peroxide values.
However, PCE, SPCE and POE spaghetti stored in typical packaging increased the PV by 742.8, 846.7 and 625.7%, respectively. The pasta at time 0 showed COP values of about 50 μg of COPs/g
of fat. During storage, COP values increased significantly. PCE, SPCE and POE spaghetti stored in the dark showed a content of total cholesterol oxides that was 2.0, 2.0, and 1.5 times lower than that of samples stored with typical pasta packaging
Biosensors and biosensing for analysis of lactate and malate in wines with electrochemical procedures
No full textLipid Process Markers of Durum Wheat Debranning Fractions
Full text linkAt present, whole grains are usually obtained by adding bran and middlings to refined flours, and this recombination leads to certain variations in the ratio of endosperm, bran and germ, resulting in flours with very different compositional characteristics and rheological properties. Therefore, this study focuses on the identification of specific lipid markers in different debranning fractions of Italian and Canadian durum wheat blends. The by-products obtained from five different debranning levels (3, 6, 9, 12 and 15%) had a high content of monounsaturated fatty acids and a higher concentration of tocopherols and sterols than the corresponding debranned grains. The Italian and Canadian durum wheat samples did not show significant differences in the content of these bioactive lipid compounds. In particular, palmitic acid, oleic acid, tocopherol isomers and total sterols could be useful biomarkers for evaluating the grain-to-tissue ratio in recombined flours
Satiating effect of a barley beta-glucan-enriched snack
No full textABSTRACT
Objective: Increasing viscous dietary fiber in snacks may have several nutritional advantages, especially for adolescents. Having a snack that may exert direct health benefits and that may, at the same time, contribute to the voluntary reduction of energy intake through modulation of appetite may be a useful dietary strategy for energy control in adolescence. In this short-term study, a new type of biscuit containing 5.2% barley beta-glucan was produced and its effect on appetite moods and food intake was investigated.
Methods: Twenty healthy adolescents were selected and randomly assigned to receive, as a midmorning snack, a 628 kJ (SP) or 1884 kJ (LP) preload of barley beta-glucan enriched (BB) or control (CB) biscuits. Appetite ratings before and within 2 hours following the snack, as well as the energy intake at lunch, were recorded.
Results: For all sensations, a peak at 15 minutes post-snack and a subsequent return to baseline value were shown. A decrease of the area under the curve (AUC) of the desire to eat and an increase of the AUC of fullness and satiety were recorded with SP-BB compared to SP-CB. The energy intake recorded at the lunch test was always significantly lower than that at the control lunch only in females (3048 kJ vs. 3890 kJ) independently from the type of snack consumed. Total energy intake significantly correlated with preload values both in females and in males, but not with the type of biscuit. Nutritional composition of meals consumed ad libitum did not vary significantly from those with different preloads.
Conclusions: The BB, consumed as a midmorning snack, although able to influence appetite ratings, did not modify food intake in a short time period
Microencapsulation of Phenolic Extracts from Cocoa Shells to Enrich Chocolate Bars
Full text linkCocoa bean shells were subjected to green extraction technologies, based on the absence of toxic organic solvents, to recover polyphenols; the extract was then encapsulated using a spray dryer and maltodextrin as coating agent. The best conditions observed in the spray drying tests (core-to-coating ratio 1:5; inlet temperature 150 °C; flow rate 6 ml min-1) were applied to produce the microcapsules used to enrich the same cocoa mass as the shells and processed for the preparation of the chocolate bars. Sensory analysis showed no significant differences between enriched chocolate bar and the unenriched reference one, except for the appearance. Both samples were then subjected to accelerated storage tests, at the end of which the polyphenols in the control chocolate bar (0.85 g 100 g-1) were reduced by about 50% (0.42 g 100 g-1), while in the enriched chocolate (1.17 g 100 g-1) by only 22% (0.97 g 100 g-1). The proposed process significantly enriched the chocolate bars with phenolic antioxidants recovered from cocoa waste without increasing the sensations of bitterness and astringency
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Olfactory Response of Sitophilus zeamais Adults to Odours of Semolina Pasta and Semolina Pasta Enriched with Different Amounts of Acheta domesticus Powder
No full textThe behavioural response of adult maize weevil, Sitophilus zeamais, to different types of semolina pasta enriched or not enriched with increasing proportions (5%, 10%, and 15%) of house cricket (Acheta domesticus) powder was investigated in olfactometer arena bioassays by using trap devices. In the five-choice behavioural bioassays, the number of S. zeamais adults attracted to 100% durum wheat semolina pasta was significantly higher than those attracted to the other pasta types enriched with A. domesticus powder. In the two-choice behavioural bioassays, the Response Index for each pasta type was positive and significant. However, although not significant, there was a progressive reduction in the Response Index as the cricket powder content increased. In similar experiments, there were no significant differences between cricket powder alone and the control in the number of attracted S. zeamais, indicating a neutral effect towards insects. These observations suggest that the lower attractiveness of pasta enriched with house cricket powder is mainly due to the masking of host food odours. Solid-phase microextraction coupled to gas chromatography-mass spectroscopy identified a total of 18 compounds in the head-space samples of the different types of pasta, highlighting differences in volatile composition. Some volatile compounds were only present in the pasta produced with cricket powder. In particular, 1-octen-3-ol and phenol were present in the samples containing 5%, 10%, or 15% cricket powder; pentanal, benzaldehyde, and dimethyl disulphide were present in samples containing 10% or 15% cricket powder; and 2,5-dimethyl-pyrazine was present in the sample containing 15% cricket powder. Further investigation with individual compounds and mixtures is needed to define the chemical basis of the differences in the insect olfactory preference observed in this study
Evaluation of carotenoids and furosine content in air dried carrots and parsnips pre-treated with pulsed electric field (PEF)
Full text linkCarrot and parsnip slices were subjected to hot drying at 50, 60 and 70 °C with or without pulsed electric field (PEF) pretreatment
at 0.9 kV/cm and 1000 and 10,000 pulses. The effect of drying on processed samples was assessed by analysis of
carotenoids, the furosine value, total phenols and the Whiteness Index (WI). PEF pre-treatment is effective in reducing drying
times, but the degree of cellular breakdown makes the compounds more susceptible to chemical and enzymatic reactions. In
our condition PEF pre-treatment increased the carotenoid degradation and promoted the Maillard reaction above all at the
highest temperature of 70 °C. The assessment of carotenoid stability, together with the furosine value, were confirmed to
be useful tools for the evaluation of effects of thermal damage and quality of dried food products, also after different drying
treatments
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