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关键词： Greenhouses  

摘要： To improve direct sun drying, small drying tunnel units, elevated above the ground and covered by insect-proof nets, were designed. We investigated the effect of these locally made solar dryers, placed in open air and under plastic greenhouse, on dried fig quality of three local varieties (two San Pedro types and one Smyrna type). The results showed that fruit lightness and yellowness were improved when figs were dried under plastic greenhouse. No significant effects of variety and drying methods were registered for total soluble solids, and glucose and fructose contents. A total of 104 volatile compounds were identified in Tunisian dried figs. Most of volatiles except acetic acid were influenced mostly by variety. The sensory analysis revealed significant differences between drying techniques. Figs dried under plastic tunnel were the most appreciated. Solar dryer under plastic tunnel could be a good alternative for rural farmers to substitute the traditional sun drying techniques. Novelty impact statementThis work provides beneficial knowledge for improving the appearance and organoleptic quality of dried figs considering combined effect of variety and drying method. Plastic tunnel dryer is a good alternative for rural farmers to substitute the traditional open air sun drying. This method enhances the quality of products with minimum costs and short duration of dehydration.

关键词： Thermal characterization   Oxidative decomposition   Phenolic compounds   Lauric acid  

摘要： Vegetable oils are subjected to heat treatments during processing and changes during storage. Thus, it is required, for usage as a food source, the evaluation of their thermo-oxidative stability and physicochemical characteristics. In this context, the objective of this paper was to evaluate the oil of catole coconut (Syagrus cearensis), aiming to characterize its identity and quality, as well as its antioxidant capacity and thermo-oxidative stability. The catole coconut was collected in the city of Lagoa Seca-PB, Brazil, its almonds were dried in a stove and the catole oil was obtained by cold pressing. The results of the physicochemical parameters complied with the current legislation, with average values of 2.48 mg KOH g(-1) oil for acid value, 0.14 meq peroxide kg(-1) oil for peroxide value and 253 mg KOH g(-1) oil for saponification value. Catole oil presented the profile of saturated fatty acids (84.42%), with the predominance of lauric acid (45.06%), besides major phenolic compounds such as salicylic acid [12.324 mg (100 g(-1)) of oil] and myricetin [1.405 mg (100 g(-1)) of oil]. The thermogravimetric profile remained stable to decomposition at temperatures up to around 240 degrees C and oxidative stability withstood at 110 degrees C for more than 48 h. Therefore, it was possible to identify and characterize this unexplored oilseed species of the Brazilian semiarid, diversifying its use in the food industry.

关键词： Cowpea starch   Physical modification   Functional properties   In vitro starch digestibility   Structural properties  

摘要： Cowpea (Vigna unguiculata) starch was physically modified by heat moisture treatment (HMT) or HMT followed by ultrasound treatment (UST). The modifications of starch crystallinity, morphology and digestibility as well as thermal, and pasting characteristics were evaluated. HMT was performed at 20% moisture content, for 2, 5 and 12 h at 100 degrees C (HMT2, HMT5, HMT12). UST was performed at 80% amplitude (20 kHz) for 30 min (2 s on-2 s off). The granule shape and XRD patterns were not modified by any of the applied treatments. 1H NMR revealed that HMT and HMT-UST caused a decrease of amylopectin branching degree. Thermal stability increased more in heat-moisture-treated-starch, while gelatinization enthalpy was not affected by the treatments applied. The resistant starch content increased up to 11% with HMT, whereas an increase in slow digestible starch (SDS) (+30%) was observed in HMT2-UST and HMT5-UST. The decrease in pasting viscosity of treated starch samples increased incrementally with heating time. The results demonstrate that HMT and HMT-UST expand the opportunities and potential of using modified cowpea starches as ingredients in several food applications.

关键词： PVA/CMC   Hydroxyapatite   UV/Vis   Dielectric properties   Antimicrobial properties  

摘要： Hydroxyapatite nanoparticles doped with silver AgHA-NPs were synthesized successfully then added with various mass fractions to a mixed solution of polyvinyl alcohol (PVA)/carboxymethyl cellulose (CMC) using the casting technique. Experimentally, the influence of silver doped hydroxyapatite nanoparticles on the structural, optical, dielectric and antimicrobial properties of nanocomposite films was investigated. X-ray diffraction and Fourier transformation infrared spectroscopy were used to explore the structural features of these films. The XRD analysis revealed the amorphous nature of PVA/CMC blend and the intensity of the characteristic peak of the virgin polymers in the nanocomposite spectrum being much reduced as the doping level was increased. The FT-IR spectra indicated that the blend components were miscible by revealing the functional groups of two polymers that interacted through the formation of a hydrogen bond while, the FT-IR spectra of nanocomposite confirmed the good interaction between the blend chains and AgHA-NPs. The morphological graphs of the prepared blend were formed as hexagonal grains with size distribution around 18.36-24.11 mu m. The addition of AgHA-NPs changed the surface morphology of the blend significantly. The optical properties of PVA/CMC blend and nanocomposites films were measured in the 200-800 nm wavelength range. Optical measurements showed that the optical transmittance for pure blend was nearly 90% while it decreased to 50% with increasing AgHA-NPs contents up to 40 wt.%. The energy gap values calculated by Tauc's model and those determined by ASF model are consistent, where their values reduced by AgHA-NPs incorporation. The dielectric constant of all samples were studied in range of temperatures (303-405 K) and from100 kHz to 1.0 MHz, range of frequencies. The Correlated Barrier Hopping (CBH) is the most appropriate conduction mechanism based on the frequency dependence of the ac conductivity. Silver ion release was examined

关键词： colored potatoes   DSC   HPSEC   particle size distribution   starch  

摘要： Potatoes, especially colored, are perceived as a valuable source of bioactive compounds, and they are also an important raw material for starch production. There is virtually no information about starch from colored potatoes grown in Central Europe. Therefore, starches from light and colored potato varieties are isolated, and their particle size distributions, molecular masses, phosphorus content, gelatinization properties, water binding capacity, and solubility are analyzed. It is found that the mean and minimum granule size is similar for all investigated varieties, but colored varieties have larger granules. Moreover, starches isolated from colored potatoes are characterized by a higher phosphorus content than those isolated from light ones. It is shown that the solubility and water-binding capacity of starch from colored potatoes is greater than that of light flesh, especially at higher temperatures. Starches from light flesh potatoes are characterized by significantly higher gelatinization enthalpy values than those from colored potatoes.

关键词： Highland barley   Enzyme inactivation pretreatment   Edible quality   Thermo-pasting properties  

摘要： Enzyme inactivation is vital to improve the shelf life of highland barley (HB), but the impacts of different heating assisted enzyme inactivation pretreatment (HAEIP) on structure, physicochemical properties and edible quality remain unclear. This study evaluated the effects of three representative HAEIP for microwave, roasting and superheated steam (SS) on the properties of HB grain and flour based on the 50% or 60% inactivation rates for lipase and complete inactivation for peroxidase. Results showed that microwave and SS treatments had the highest and lowest cracking ratio respectively. For the HB edible qualities, the shorter cooking times were observed in R-60 (26 +/- 0.84), SS-50 (27 +/- 0.09) and SS-60 (27 +/- 0.07) groups. Meanwhile, the hardness and chewiness of roasted HB were significantly higher than that in microwaves and SS groups. The HB flour properties varied with different HAEIP. Although all pretreatments showed a substantial reduction in the flour viscosities with treatments intensity increased, the PV values in the two SS groups were the highest. The microwave treatment had the biggest impact on the relative crystallinity and gelatinization degree, while SS pretreatment had the best performance and could be an effective, practical enzyme inactivation methods and enhance HB product quality.

关键词： Oat-based drink   Wholemeal oat   Oat bran   Physical stability   Physicochemical properties  

摘要： The popular dairy alternative oat-based drink (OBD) is made from hydrolysed oat. However, natural OBD is inherently unstable. OBD is commonly made from wholemeal oat and considered to have health benefits due to the beta-glucan content. beta-glucan is also a hydrocolloid with stabilizing potential and stored mainly in the bran. This study investigated the effect of bran substitution, to traditional wholemeal oat on the stability and physicochemical properties of OBD. In addition, the effect of the loss of the beta-glucan network at neutral and acidified pH are also assessed. Products with intact beta-glucan from bran were highly viscous and, thus, stable throughout storage at 20 degrees C for 14 days, but showed a viscous gel-like tendency that is unsuitable for thin beverage applications. The loss of the beta-glucan network made thin beverage-like products that were unstable. The instabilities observed were phase separation due to thermodynamic incompatibility (bran pH 6.4), gravity separation-based creaming (wholemeal pH 6.4 and 4.2), and electrostatic complex formation (bran pH 4.2). The complex formation highlighted the slight anionic tendency of hydrolysed beta-glucan. The use of bran fraction leads to higher protein and beta-glucan content. The physicochemical balance of the products greatly influenced the stability of the product.

关键词： Lactobacillus fermentation   phosphorus content   physicochemical properties   potato starch  

摘要： The effect of different levels of phosphorus on the process of amylolytic Lactobacillus fermentation and physicochemical properties of potato starch samples are investigated. The low-phosphorus starch (LPS), medium-phosphorus starch (MPS), and high-phosphorus starch (HPS) samples, the phosphorus contents in which are 422.7, 729.5, and 936.2 mg kg(-1), respectively, are selected for fermentation. The maximum rate of Lactobacillus fermentation is observed in HPS, and the lowest rate of fermentation is recorded for MPS. The effect of phosphorus content on fermentation rate shows a different tendency from enzymatic hydrolysis. The process of fermentation exerted significant effects on the thermodynamic properties of MPS and HPS (p < 0.05). Fermentation is also found to exert significant effects on the pasting properties (exception: pasting temperatures) of potato starch samples (p < 0.05). It also influenced the properties of adhesiveness, springiness, and resilience of HPS gels and the chewiness and gumminess of MPS gels (p < 0.05). The principal component analysis results suggested that phosphorus and fermentation significantly affect the physicochemical properties of potato starch that is used to make different staple food items.

关键词： bovine lactoferrin   zinc-lactoferrin interactions   whey proteins   metallocomplexes  

摘要： One trend of the modern world is the search for new biologically active substances based on renewable resources. Milk proteins can be a solution for such purposes as they have been known for a long time as compounds that can be used for the manufacturing of multiple food and non-food products. Thus, the goal of the work was to investigate the parameters of Znbovine lactoferrin (bLTF) interactions, which enables the synthesis of Zn-rich protein complexes. Zinc-bLTF complexes can be used as food additives or wound -healing agents. Methodology of the study included bLTF characterization by sodium dodecyl sulfate-PAGE, MALDI-TOF, and MALDI-TOF/TOF mass spectrometry as well Zn-bLTF interactions by attenuated total reflection-Fourier-transform infrared, Raman spectroscopy, scanning and transmission microscopy, and zeta potential measurements. The obtained results revealed that the factors that affect Zn-bLTF interactions most significantly were found to be pH and ionic strength of the solution and, in particular, the concentration of Zn2+. These findings imply that these factors should be considered when aiming at the synthesis of Zn-bLTF metallocomplexes.

关键词： fermented goat milk   proteolysis   viscosity   gastrointestinal conditions  

摘要： We evaluated the performance of Limosilactobacillus mucosae CNPC007 as an autochthonous adjunct cul-ture in the production of goat milk Greek-style yogurt. The techno-functional, physicochemical, and sensory characteristics of the control yogurt (containing only starter culture, CY) and the probiotic yogurt (with the probiotic strain added, PY) were assessed during 28 d of refrigerated storage. Furthermore, we determined the survival of the strain throughout the gastrointestinal tract under simulated conditions. The PY yogurt had a lower extent of proteolysis index and a higher depth of proteolysis index. These results indicate that the proteolytic enzymes of L. mucosae may have a possible action in PY. The PY formulation exhibited viscosity almost 1.5 times as high as CY over the refrigeration period, probably due to higher production of exopoly-saccharides by the probiotic strain, which directly in-terferes with the microstructure, texture, and viscosity of the product. The PY formulation received higher scores for color, flavor, and global acceptance at 1 d of storage and higher texture scores at 28 d. The counts of L. mucosae remained high (>7 log cfu/g and >8.5 log cfu/g) throughout mouth-ileum digestion and storage, respectively, in PY. The autochthonous adjunct culture of L. mucosae CNPC007 can be used for production of a novel potentially probiotic goat yogurt without negatively affecting the general characteristics of the product quality, adding value associated with maintain-ing its functional potential.