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Uninformative biological variability elimination methods were studied in the near-infrared calibration model for predicting the soluble solids content of apples. Four different preprocessing methods, namely, Savitzky-Golay smoothing, multiplicative scatter correction, standard normal variate, and mean normalization, as well as their combinations were conducted on raw Fourier transform near-infrared spectra to eliminate the uninformative biological variability. Subsequently, robust calibration models were established by using partial least squares regression analysis and wavelength selection algorithms. Results indicated that the partial least squares calibration models with characteristic variables selected by CARS method coupled with preprocessing of Savitzky-Golay smoothing and multiplicative scatter correction had a considerable potential for predicting apple soluble solids content regardless of the biological variability. [ABSTRACT FROM AUTHOR]

Apple pomace is a promising source of carbohydrates, proteins, amino acids, fatty acids, phenolic compounds, vitamins, and other compounds with a vast range of food applications. This review focuses on the valorization of apple pomace towards the recovery of the main compounds, namely pectin and polyphenols. Applications, advantages, and drawbacks of conventional extraction (acidic medium under high temperatures) compared with novel extraction technologies are presented. The comparison is based on an extensive literature review of research on extraction of valuable compounds from plant matrixes, particularly apple pomace. Novel extraction techniques involving enzymes, electric field, ultrasound, microwave heating, pressurized liquid, and super/subcritical fluid are also discussed. These techniques offer several advantages, including shorter extraction time, increased yield, reduction-or suppression-of solvents, and minimization of the environmental impact. This paper may help researchers and food industry professionals on the scaling-up and optimization of eco-friendly extractions of pectin and phenolic compounds. [ABSTRACT FROM AUTHOR]

The polyphenol profile of apple ( Malus × domestica) is dominated by the dihydrochalcone glycoside phloridzin, but its physiological role is yet to be elucidated. Biosynthesis of phloridzin occurs as a side branch of the main phenylpropanoid pathway, with the final step mediated by the phloretin-specific glycosyltransferase UGT88F1. Unexpectedly, given that UGTs are sometimes viewed as 'decorating enzymes', UGT88F1 knockdown lines were severely dwarfed, with greatly reduced internode lengths, narrow lanceolate leaves, and changes in leaf and fruit cellular morphology. These changes suggested that auxin transport had been altered in the knockdown lines, which was confirmed in assays showing that auxin flux from the shoot apex was increased in the transgenic lines. Metabolite analysis revealed no accumulation of the phloretin aglycone, as well as decreases in many non-target phenylpropanoid compounds. This decreased accumulation of metabolites appeared to be mediated by the repression of the phenylpropanoid pathway via a reduction in key transcript levels (e.g. phenylalanine ammonia lyase, PAL) and enzyme activities ( PAL and chalcone synthase). Application of exogenous phloridzin to the UGT88F1 knockdown lines in tissue culture enhanced axial leaf growth and partially restored some aspects of 'normal' apple leaf growth. Together, our results strongly implicate dihydrochalcones as critical compounds in modulating phenylpropanoid pathway flux and establishing auxin patterning early in apple development. [ABSTRACT FROM AUTHOR]

Flavonoids are major polyphenol compounds in plant secondary metabolism. Wild red-fleshed apples ( Malus sieversii f . niedzwetzkyana) are an excellent resource because of their much high flavonoid content than cultivated apples. In this work, R6R6, R6R1 and R1R1 genotypes were identified in an F1 segregating population of M. sieversii f . niedzwetzkyana. Significant differences in flavonoid composition and content were detected among the three genotypes by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry analysis. Furthermore, two putative flavonoid-related genes encoding R2R3- MYB transcription factors, designated MYB12 and MYB22, were cloned and characterized. The expression patterns of MYB12 and MYB22 directly correlated with those of leucoanthocyanidin reductase and flavonol synthase, respectively. Their roles in flavonoid biosynthesis were identified by overexpression in apple callus and ectopic expression in Arabidopsis. MYB12 expression in the Arabidopsis TT2 mutant complemented its proanthocyanidin-deficient phenotype. Likewise, MYB22 expression in an Arabidopsis triple mutant complemented its flavonol-deficient phenotype. MYB12 could interact with bHLH3 and bHLH33 and played an essential role in proanthocyanidin synthesis. MYB22 was found to activate flavonol pathways by combining directly with the flavonol synthase promoter. Our findings provide a valuable perspective on flavonoid synthesis and provide a basis for breeding elite functional apples with a high flavonoid content. [ABSTRACT FROM AUTHOR]

The effect of instant controlled pressure drop-assisted hot air drying ( AD- DIC) on browning-related components in apple slices was studied. Results showed the AD temperature had no significant effect on colour index of final apple slices. The aspartic acid, glutamic acid, lysine, histidine, arginine, sucrose and dehydroascorbic acid ( DHAA) in apple slices increased firstly during the AD process and then decreased during DIC process. The fructose, glucose, reduced ascorbic acid and major phenolic compounds reduced with the abrupt increase of 5-hydroxymethylfurfural (5- HMF) during AD- DIC. There were significant correlations ( P < 0.05) among moisture content ( w.b.), water activity ( a w), water state, reduced ascorbic acid, DHAA, chlorogenic acid, procyanidin B1, (+)-catechin, (−)-epicatechin and phlorizin during AD- DIC. The colour difference showed that the major browning reaction of apple slices during the predrying process was enzymatic browning, while nonenzymatic browning played a crucial role on green-red value ( CIE a* value) during DIC. [ABSTRACT FROM AUTHOR]

Based on limited research concerning the aroma of apple ciders and the goal of increasing the utilization of apple pomace, we evaluated the sensory profiles of apple homogenate ciders made with koji, Saccharomyces cerevisiae, or a mixture of both. Sensory analyses demonstrated that ciders made with pure and mixed koji cultures have significantly different physicochemical, aroma and taste profiles compared to ciders made with S. cerevisiae. Aroma compound identification showed that pure and mixed koji cultures produced volatile components in high abundance and contained similar amounts of esters and alcohols compared with S. cerevisiae monocultures. These results suggest that koji cultures could be used to augment the quality of ciders made traditionally with S. cerevisiae alone. The production of apple homogenate ciders using koji cultures could reduce production costs by eliminating the need for added sweeteners and increasing the utilization of apple pomace, adding value to the raw apple product. [ABSTRACT FROM AUTHOR]

The extraction of water-soluble dietary fiber ( SDF) from apple pomace ( AP) by cellulase, microwave- and ultrasound-assisted methods was studied in comparison with conventional acid method. The functional properties of extracted SDFs were further evaluated, and the speciality of each method was clarified in order to suggest the right method to adopt for practice. Results indicated that AP is rich in SDF, which is significantly potential to be applied in food processing. Acid hydrolysis of AP gave 10.3% of SDF, whereas ultrasound-assisted extraction ( UAE) provided a yield of 16.4% after 40 min of sonication. Microwave-assisted extraction ( MAE) gave a slightly lower yield (14.9%) than UAE, but it showed a drastic efficiency, wherein the yield was achieved after 2 min of irradiation. The hydrolysis of AP by cellulase occurred with the highest SDF yield (18.7%) among all the methods used. The functional properties of SDF were improved by UAE, MAE and cellulase extraction, wherein the water retention and swelling capacities were increased more considerably than the oil retention capacity. Especially, cellulase showed a remarkable performance in improving the hydration property. Practical Applications A large amount of apple pomace ( AP) was produced as the by-product of apple processing in China. Its disposal is of significance in consideration of resource utilization and environmental protection. Therefore, the results of this study can promote the full use of AP and similar industrial wastes, and also help to avoid possible pollution. In addition, the comparison of acid, cellulase, microwave- and ultrasound-assisted methods suggests the right method to adopt SDF extraction method for practice. [ABSTRACT FROM AUTHOR]

The response surface methodology was used to investigate the effects of blackcurrant concentrate level, vacuum pressure and time on the mass transfer and nutritional properties of vacuum-impregnated apple cubes. There were higher water loss and weight reduction in the samples at the middle-level vacuum pressure, but the other factors had no effect on these properties. The higher the vacuum pressure and time, the higher the solids gain of the samples. There was opposing results of the antioxidant capacity of the samples in the middle and high blackcurrant concentrate level and vacuum pressure when compared with the low blackcurrant concentrate level and high vacuum pressure. The middle blackcurrant concentrate level gave higher ascorbic acid content of the samples, while the middle vacuum pressure gave lower values. The optimised conditions for vacuum impregnation of the apple cubes were 18-20% blackcurrant concentrate level, 77-80 kPa vacuum pressure and 38-45 min vacuum time. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts.The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas.The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated.The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides. [ABSTRACT FROM AUTHOR]

Flowering plant species in hedgerows may be food sources for beneficial insects and therefore play a role in biodiversity conservation and agroecosystem functioning. Research was conducted in eight organic cider-apple orchards in Asturias ( north-west Spain) aiming to (i) identify the native flowering plants in the surrounding hedgerows and (ii) assess the attractiveness of those flowers for beneficial insects, such as pollinators and natural enemies of pests., A total of 7745 flowers belonging to 63 plant species were recorded in the hedgerows from May to September 2012. Flower abundance and species richness decreased as the season progressed. Orchard differences were observed for plant species richness but not for the total number of flowers in the hedgerows, likely as a result of similar management among orchards., Hymenoptera pollinators (honey bees, bumblebees and wild bees) accounted for 37.8% of the total insects recorded visiting flowers, whereas predatory hoverflies (14.9%) were the dominant natural enemies., The attractiveness for insects was assessed for 21 of the flowering plant species identified in the hedgerows. Flowering plants differed in the number of taxa that they attracted and in their attractiveness for particular insect groups and for insects as a whole., The present study described the floral composition of the hedgerows that surround apple orchards and identified the local floral resources that could provide benefits for farmers by improving ecosystem services of pollination and biological control of pests. [ABSTRACT FROM AUTHOR]

The adsorption-influencing factors such as pH, dose, and time were optimized by batch adsorption study. A 0.8 g dose, 4.0 pH, and 80 min of contact time were optimized for maximum adsorption of Pb on AP The adsorption isotherms (Langmuir and Freundlich) were well fitted to the data obtained with values of qmax (16.39 mg/g; r² = 0.985) and K (16.14 mg/g; r² = 0.998), respectively. The kinetics study showed that lead adsorption follows the pseudo-second-order kinetics with correlation coefficient (r²) of 0.999 for all of the concentration range. FTIR spectra also showed that the major functional groups like polyphenols (-OH) and carbonyl (-CO) were responsible for Pb binding on AP The thermodynamic parameters as ΔG, ΔH (33.54 J/mol), and ΔS (1.08 J/mol/K) were also studied and indicate that the reaction is feasible, endothermic, and spontaneous in nature. [ABSTRACT FROM AUTHOR]

Our previous studies demonstrated that an 8-week intake of 5% (w/w) apple polyphenol (APP) in the diet improves muscle endurance of young-adult rats. In order to identify a lower limit of the dietary contribution of APP to the effect, the experiments were designed for lower-dose supplementation (8-week feeding of 0.5% APP in AIN-93G diet) to 12-week-old male Sprague-Dawley rats. Results clearly showed that the 0.5% APP diet significantly up-regulates slower myosin-heavy-chain (MyHC) isoform ratios (IIx and IIa relative to total MyHC) and myoglobin expression in lower hind-limb muscles examined ( P < 0.05). There was a trend to increased fatigue resistance detected from measurements of relative isometric plantar-flexion force torque generated by a stimulus train delivered to the tibial nerve ( F(98, 1372) = 1.246, P = 0.0574). Importantly, there was no significant difference in the animal body-phenotypes or locomotor activity shown as total moving distance in light and dark periods. Therefore, the present study encourages the notion that even low APP-intake may increase the proportions of fatigue-resistant myofibers, and has promise as a strategy for modifying performance in human sports and improving function in age-related muscle atrophy. [ABSTRACT FROM AUTHOR]