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In the rice processing industry, wastewater is an inevitable by-product of rice washing. To increase the utilization of washed rice water (WRW), seven types of fermented washed rice water (FWRW) were prepared using lactic acid bacteria (LAB) and carbohydrate hydrolase. The total concentration of small maltooligosaccharides (MOSs) in the amyloglucosidase (AMG) treatment groups was about ten times higher than in the untreated groups. After 6 h of fermentation, six of the seven FWRW samples reached a pH of 4 due to the increased concentration of organic acids and could, therefore, be used as food acidity regulators. To confirm the applicability of FWRW, the traditional Korean rice cake garaetteok was prepared with FWRW and stored at 4 °C for 5 days. A texture profile analysis (TPA) revealed that the hardness of garaetteok treated with FWRW was significantly lower than that of untreated garaetteok following storage. Differential scanning calorimetry (DSC) showed that FWRW retarded the retrogradation of garaetteok during storage. The addition of FWRW using Lactobacillus reuteri with an AMG group was particularly effective for inhibiting microbial activity in garaetteok during storage. These results suggest that FWRW using AMG-added L. reuteri can be used as a novel food additive for improving the quality of traditional Korean starch foods and could also reduce the volume of waste WRW.

Well-developed clastic shoreline systems have been deposited in the Gippsland Basin over a 70 Ma period, from the latest Cretaceous to the present day. Twenty-three stacked coastal units have been mapped and described in the Traralgon and Balook formations of the Latrobe and Seaspray groups. These units are made up of prograding and backstepping shoreface deposits, which, in plan view, display well-developed strandline geometries at the terrestrial–marine interface. Shoreface deposits are interpreted to include prograding beach, barrier island and transgressive beach deposits. The lower coastal plain is characterised by persistent deposition of coals despite changes in shoreface type and significant palaeoclimate fluctuations. These coastal deposits display approximately 123 km of transgression from the Late Cretaceous shoreline at the base of the study interval to the mid Miocene Yallourn Formation near the top. The Late Cretaceous and Palaeocene shoreline deposits individually prograde and are separated by flooding surfaces reflecting eustatic changes. Overall they display long-term backstepping behaviour (retrogradation) as a result of basin subsidence. Though shorelines of the Eocene–Miocene are distinctly transgressional, probably reflecting basin subsidence, in the mid-Miocene they become individually and collectively progradational. A series of unconformities in the Oligocene, coupled with Miocene progradation, likely reflects a combination of a compressional tectonic regime and glacioeustatic fluctuations. Despite major changes in the tectonics and palaeoclimate, basin subsidence appears to be the dominant driver for changes in shoreline location.

This study is devoted to assessing the hygroscopic and durability properties of a clay composite with the addition of a natural polymer. Modified polymer-retrograded starch hydrogel (RSH) of various concentrations (2.5, 5.0, 7.5, and 10.0%) and heating times (3 and 5 h) were used as clay stabilizers. The introduction of retrograded starch tends to increase the drying rate of clay composites at the early period of 0–4 days without the formation of shrinkage defects. Moisture uptake increased by 29% (from 140 to 180 g/m2) over the control clay composite without RSH. The hysteresis rate of the clay samples modified with RSH decreased by half (from 0.3 to 0.15%), but the hygroscopic properties were better. The use of RSH polymer increased the durability (water erosion resistance) of the clay composite. The obtained composite has great potential for indoor use due to its high moisture-regulating and durability properties.

Improving the quality with desired functions of natural starch through agronomic practice will meet the increasing need of people for natural, functional foods. A one-off application of slow-release fertilizer is a simple and efficient practice in maize production, though its influence on the starch quality is scarce. In the present study, the structural and functional properties of the starch of normal maize under two fertilization modes (one-off application of slow-release fertilizer at the sowing time (SF), and three applications of conventional fertilizer at the sowing time, and topdressing at the jointing and flowering stages (CF)) under the same fertilization level (N/P2O5/K2O = 405/135/135 kg/ha) were studied using Jiangyu877 (JY877) and Suyu30 (SY30) as materials. The observed results indicate that the size of starch granules was enlarged by fertilization and the size was the largest under CF in both hybrids. The amylose content was unaffected by CF and reduced by SF in both hybrids. In comparison to no fertilizer (0F), the peak 1/peak 2 ratio was decreased by CF in both hybrids, whereas the ratio under SF was unaffected in JY877 and decreased in SY30. The amylopectin average chain-length was reduced by fertilization and the reduction was higher under CF in JY877. The relative crystallinity was increased by CF in both hybrids and the value under SF was unaffected in SY30 and increased in JY877. The peak, trough, and final viscosities of starch were increased by fertilization in both hybrids. The starch thermal characteristics in response to fertilization modes were dependent on hybrids. The retrogradation enthalpy and percentage were increased by CF in both hybrids, whereas those two parameters under SF were increased in SY30 and decreased in JY877. In conclusion, starch with similar granule size, higher peak 1/peak 2 ratio, and lower relative crystallinity was obtained under SF than under CF for both hybrids. Longer amylopectin chain-length was observed in JY877, which induced lower pasting viscosities in SY30 and lower retrogradation characteristics in JY877.

The impact of konjac glucomannan (KGM) with different molecular weight (Mw) on the retrogradation properties of pea starch, such as color, viscoelasticity, gel strength, water holding capacity (WHC), moisture distribution and crystallinity, was investigated. At the same time as the Mw of KGM decreased, the lightness, elastic modulus, gel strength, water freedom and crystallinity of pea starch showed an increasing trend, whereas the viscosity modulus and WHC showed a decreasing trend. At one day of storage, compared with single pea starch, KGM with low Mw made gel strength increase from 40 g to 45 g, WHC decrease from 82% to 65% and crystallinity increase from 21.3% to 24.0%. Therefore, KGM with low Mw could promote retrogradation of pea starch in the short-term. At 7 days or even 14 days of storage, KGM with medium-high Mw had smaller indices than those of pure pea starch, including the lightness, storage modulus, gel strength, water freedom and crystallinity. This indicated that KGM with medium-high Mw could inhibit the long-term retrogradation of starch. The larger the Mw of KGM, the more noticeable the inhibition effect.

The purpose of this study was to compare the gelatinization and retrogradation properties of highland barley starch (HBS) using different extraction methods. We obtained HBS by three methods, including alkali extraction (A-HBS), ultrasound extraction (U-HBS) and enzyme extraction (E-HBS). An investigation was carried out using a rapid viscosity analyzer (RVA), texture profile analysis (TPA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier-transform infrared spectrometry (FTIR). It is shown that the different extraction methods did not change the crystalline type of HBS. E-HBS had the lowest damaged starch content and highest relative crystallinity value (p < 0.05). Meanwhile, A-HBS had the highest peak viscosity, indicating the best water absorption (p < 0.05). Moreover, E-HBS had not only higher G′ and G″ values, but also the highest gel hardness value, reflecting its strong gel structure (p < 0.05). These results confirmed that E-HBS provided better pasting stability and rheological properties, while U-HBS provides benefits of reducing starch retrogradation.

Introduction. The main component of quinoa grain is starch, the properties of which affect the quality of quinoa-based food products. There is no information about quinoa starch in the Russian scientific literature. Therefore, the review summarizes and presents foreign knowledge about the isolation, chemical composition, structure, and physicochemical properties of quinoa starch Study objects and methods. The research featured scientific articles and chapters of scientific books on the structure and chemical composition of quinoa published over the past 10 years. The work used empirical and theoretical methods of scientific research. Results and its discussion. Currently, starch from quinoa grain is produced only under laboratory conditions by various methods of grinding and soaking. Most studies point to up to 10% of amylose in quinoa starch. Amylopectin in quinoa starch has a high number of short single chains and a very low number of long single chains, and their ratio is higher than that in other starches. The granule size of quinoa starch is 0.4–2.0 microns, which is significantly smaller than that of most starches. Quinoa starch belongs to polymorphic type A. The gelatinization temperature and enthalpy of quinoa starch are lower than those of amaranth, corn, sorghum, millet, and wheat starch, which is probably due to the fine structure of amylopectin. With an increase in temperature for every 10°C, the swelling force and solubility of quinoa starch increase on average by 21.5–27%. As the temperature rises from 55 to 65°C, the solubility index of quinoa starch increases sharply by 5–10 times. The viscosity of quinoa starch is significantly higher than that of most known starches. It also is more sensitive to enzymes. Conclusion. The work presents the results of scientific research on various matters: methods of starch isolation from quinoa, its chemical composition, and methods of amylose determination; structure of starch grains, their shape, type, and degree of crystallization; physicochemical properties of starch, including gelatinization, swelling, solubility, rheological properties, retrogradation, changes in the transparency of starch gel, and susceptibility to enzymes. The latter determines the choice of technological parameters in the development of formulations and food technologies, including functional foods for people with gluten intolerance (celiac disease). Further studies of the chemical composition of quinoa can help to meet the growing demand for these products and expand the range of the domestic market for gluten-free foods.

Starch retrogradation is desirable for some food textures and nutritional traits but detrimental to sensory and storage qualities of other foods. The objective of this study was to determine the impact of sweetener structure and concentration on the retrogradation of wheat starch gels. The effects of 20 sweeteners selected based on common food usage and stereochemical structures of interest, and ranging in concentration from 10 to 50%w/w, on the retrogradation of wheat starch gels were monitored spectrophotometrically over time. The sweeteners were sucrose, xylose, ribose, glucose, galactose, fructose, mannose, mannitol, L-sorbose, xylitol, tagatose, allulose, maltose, lactose, isomaltulose, isomalt, sorbitol, maltitol, and raffinose. Retrogradation rates and amounts were compared by Avrami equation rate constants (k = 0.1–0.7) and absorbance values measured on day 28 (Abs = 0.1–1.0), respectively. Both sweetener concentration and type significantly affected retrogradation. Gels made with sugar alcohols and high sweetener concentrations (≈≥40%) tended to retrograde more and faster, whereas gels made with sugars and low sweetener concentrations tended to have lower retrogradation rates and amounts. Sweeteners with more equatorial and exocyclic hydroxyl groups (e.g., glucose and maltitol) and those with larger molar volumes (e.g., isomaltulose and raffinose) tended to increase the rate and amount of retrogradation, particularly at higher concentrations. The impact of sweeteners on retrogradation was a balance of factors that promoted retrogradation (intermolecular interactions and residual short-range molecular order) and inhibiting behaviors (interference at crystallization sites), which are influenced by sweetener concentration and structure. Understanding which sweeteners at which concentrations can be used to promote or inhibit retrogradation is useful for product formulation strategies.

The object of research is the technology of modified potato starch obtained by heat-moisture treatment.Heat-moisture treatment (HMT) of starch is a hydrothermal treatment technique to modify their functional properties. Setback viscosity of potato starch gelatinization characteristic is the key factor that influences the quality of potato starch noodle. In order to obtain a green, safe and highly efficient potato starch product for vermicelli production, this study take setback viscosity as response value, a Box-Behnken model was established on the basis of single factor experiment results to optimize the modify technique. A response surface analysis was used to investigate the effects of moisture content of starch, heat-moisture treatment temperature and heat-moisture treatment time on setback viscosity of heat-moisture treatment modified potato starch. The viscosity properties, textural properties and retrogradation characteristics of HMT starch gel were estimated. The results of response surface methodology showed the optimal parameters of HMT were that moisture content of potato starch was 23.56%, heat-moisture treatment temperature was 90°C, and heat-moisture treatment time was 1.5h. Under such conditions, setback viscosity of heat-moisture treatment modified potato starch (HMTS) paste was 3677cP, which was higher than native starch (496cP) obviously, indicating that the gel strength and hardness of potato starch was improved significantly. Compared with native potato starch (NS), HMTS had lower peak viscosity (2966cP), lower hold viscosity (2882cP) and lower breakdown viscosity (84.50cP), but higher paste temperature (71.08°C), higher final viscosity (6559cP) and setback viscosity(3677cP).The results of retrogradation was consistent with the viscosity properties, all of which indicating that potato starch modified by heat-moisture treatment was more prone to retrogradation. TPA tests demonstrated that HMT can enhance the textural properties of starch gel. Compared with native starch (NS) gel, the hardness, cohesiveness, gumminess, chewiness and resilience of heat-moisture treatment starch (HMTS) gel were increased significantly, and there was no significant difference in springiness. Compared with native starch gel, heat-moisture treatment starch gel had better functional properties.

The object of research is the technology of modified potato starch obtained by heat-moisture treatment. Heat-moisture treatment (HMT) of starch is a hydrothermal treatment technique to modify their functional properties. Setback viscosity of potato starch gelatinization characteristic is the key factor that influences the quality of potato starch noodle. In order to obtain a green, safe and highly efficient potato starch product for vermicelli production, this study take setback viscosity as response value, a Box-Behnken model was established on the basis of single factor experiment results to optimize the modify technique. A response surface analysis was used to investigate the effects of moisture content of starch, heat-moisture treatment temperature and heat-moisture treatment time on setback viscosity of heat-moisture treatment modified potato starch. The viscosity properties, textural properties and retrogradation characteristics of HMT starch gel were estimated. The results of response surface methodology showed the optimal parameters of HMT were that moisture content of potato starch was 23.56 %, heat-moisture treatment temperature was 90 °C, and heat-moisture treatment time was 1.5 h. Under such conditions, setback viscosity of heat-moisture treatment modified potato starch (HMTS) paste was 3677 cP, which was higher than native starch (496 cP) obviously, indicating that the gel strength and hardness of potato starch was improved significantly. Compared with native potato starch (NS), HMTS had lower peak viscosity (2966 cP), lower hold viscosity (2882 cP) and lower breakdown viscosity (84.50 cP), but higher paste temperature (71.08 °C), higher final viscosity (6559 cP) and setback viscosity(3677 cP). The results of retrogradation was consistent with the viscosity properties, all of which indicating that potato starch modified by heat-moisture treatment was more prone to retrogradation. TPA tests demonstrated that HMT can enhance the textural properties of starch gel. Compared with native starch (NS) gel, the hardness, cohesiveness, gumminess, chewiness and resilience of heat-moisture treatment starch (HMTS) gel were increased significantly, and there was no significant difference in springiness. Compared with native starch gel, heat-moisture treatment starch gel had better functional properties., Об’єктом дослідження є технологія модифікованого картопляного крохмалю, отриманого шляхом вологотермічного оброблення. Вологотермічне оброблення (НМТ) крохмалю є методом гідротермічної обробки для зміни його функціональних властивостей. Знижена в’язкість крохмального клейстеру модифікованого картопляного крохмалю є ключовим фактором, який впливає на якість макаронів, виготовлених з його використанням. Для отримання екологічного, безпечного та високоефективного продукту з картопляного крохмалю для виробництва макаронних виробів у даному дослідженні на основі результатів однофакторного експерименту для оптимізації методики модифікації було обрано в’язкість, як основний критерій оптимізації. Для дослідження впливу вмісту вологи в крохмалі, температури та тривалості вологотермічного оброблення на зниження в’язкості картопляного крохмалю був використаний аналіз поверхні впливу. Досліджено реологічні властивості крохмальних клейстерів модифікованого картопляного крохмалю: в’язкість, текстурні властивості та ретроградаційні характеристики крохмального клейстеру. Результати методології реагування поверхні показали, що оптимальними параметрами (НМТ) є вологість картопляного крохмалю 23,56%, температура вологотермічного оброблення – 90°C, час вологотермічного оброблення – 1,5год. За таких умов зниження в’язкості клейстеру з модифікованого картопляного крохмалю (HMTS) становило 3677Па·с, що, очевидно, вище, ніж нативного крохмалю (496Па·с), що вказує на те, що міцність гелю та твердість картопляного крохмалю значно покращилися. Порівняно з нативним картопляним крохмалем (NS), HMTS мав нижчу пікову в’язкість (2966Па·с), нижчу в’язкість утримування (2882Па·с) і нижчу в’язкість розпаду (84,50Па·с), але вищу температуру клейстеризації (71,08°C), вищу кінцеву в’язкість (6559Па·с) і зниження в'язкості (3677Па·с). Результати ретроградації узгоджувалися з властивостями в’язкості, які вказували на те, що картопляний крохмаль, отриманий шляхом вологотермічного оброблення, був більш схильним до ретроградації. Тести TPA продемонстрували, що вологотермічне оброблення може покращувати текстурні властивості крохмального клейстеру. Порівняно з клейстером нативного крохмалю (NS), твердість, когезія, клейкість, жувальна здатність та пружність клейстеру модифікованого крохмалю (HMTS) значно підвищилися, і не було суттєвої різниці в еластичності. Крохмальний клейстер модифікованого крохмалю, отриманого шляхом вологотермічного оброблення мав кращі функціональні властивості порівняно з клейстером нативного картопляного крохмалю.

Fifteen transects of sediment cores located off the central Texas coast between Matagorda Peninsula and North Padre Island were investigated to examine the offshore record of Holocene evolution of the central Texas coast. The transects extend from near the modern shoreline to beyond the toe of the shoreface. Lithology, grain size and fossil content were used to identify upper shoreface, lower shoreface, ebb‐tidal delta and marine mud lithofacies. Interpretations of these core transects show a general stratigraphic pattern across the study area that indicates three major episodes of shoreface displacement. First, there was an episode of shoreface progradation that extended up to 5 km seaward. Second, an episode of landward shoreline displacement is indicated by 3–4 km of marine mud onlap. Third, the marine muds are overlain by shoreface sands, which indicates another episode of shoreface progradation of up to 5 km seaward. Radiocarbon ages constrain the onset of the first episode of progradation to ca 6.5 ka, ending at ca 5.0 ka when the rate of sea‐level rise slowed from an average rate of 1.6–0.5 mm/yr. Results from sediment budget calculations and sediment transport modelling based on reasonable estimates of an ancient shoreline shape and wave climate indicate that the first progradation was a result of sand supplied from erosion of the offshore Colorado and Rio Grande deltas. The transgressive phase occurred between ca 4.9 ka and ca 1.6 ka and coincided with a major expansion of the Texas Mud Blanket, which resulted in burial of offshore sand sources and the shoreface being inundated with mud. The second, more recent episode of shoreface progradation began ca 500 years ago with a maximum rate of ca 6 m/yr. This most recent change signals a healing phase of coastal evolution from the late Holocene transgressive event. Currently, the shoreline along the central Texas coast is retreating landward at an average rate of 0.30 m/yr, indicating that the second progradation event has ended.

The physicochemical properties of jackfruit seed starch (JSS) were investigated and compared with rice (RS) and potato (PS) starch. The amylose content of JSS (25%) was similar to PS (27%) but higher than RS (17%). The small granules of JSS (7.9 μm) was comparable to RS (9.7 μm), and both starches had A-type crystallinity. In contrast, PS had larger granules (43.4 μm) and displayed B-type crystallinity. The DSC results showed that peak gelatinization temperature of JSS (85.0°C) was significantly higher than RS (66.9°C) and PS (63.7°C), corresponding to higher pasting temperatures and lower swelling power at lower temperatures. There was no significant difference in stability between the starch gels after four freeze-thaw cycles. Formation of JSS gels with significantly higher hardness, chewiness and elastic modulus (G′), but lower fracturability demonstrated JSS ability to form strong gels. This would be beneficial for food applications requiring gelation with firm and elastic textural attributes.

As a natural pigment with high antioxidative activity, betanin is underutilized owing to less attention. This study aimed to investigate the impact of betanin on pasting, rheology and retrogradation properties of rice, potato and pea starches. Betanin decreased the peak, trough and final viscosity of rice and potato starches, but increased those of pea starch. Rheology measurements implied that betanin had the greatest effect on the hysteresis loops and dynamic modulus of potato starch. Betanin endowed starch pastes with a vivid red appearance and maintained the color of the starch pastes during storage. XRD analysis indicated that betanin weakened the diffraction intensities and reduced the crystallinity of the retrograded starches. Meanwhile, betanin reduced the short-range ordered structure of the retrograde starches. The results of DSC analysis found that betanin significantly depressed the retrogradation enthalpy and retrogradation rate, implying that the long-term retrogradation of starches was delayed. Furthermore, the changed morphology of the retrograded starches was observed. These results suggested that betanin could be applied as an excellent colorant and inhibitor of retrogradation in foods such as bread and pastry products.

Starch with a high amylose (AM) content (high AM starch, HAS) has attracted increasing research attention due to its industrial application potential, such as functional foods and biodegradable packaging. In the past two decades, HAS structure, functionality, and applications have been the research hotspots. However, a review that comprehensively summarizes these areas is lacking, making it difficult for interested readers to keep track of past and recent advances. In this review, we highlight studies that benefited from rapidly developing techniques, and systematically review the structure, functionality, and applications of HAS. We particularly emphasize the relationships between HAS molecular structure and physicochemical properties.

Thermoplastic starch (TPS) has emerged as an essential alternative to produce environmentally friendly packaging; however, retrogradation is a disadvantage that affects its shelf life. This study analyzed the co-plasticizing effect of isosorbide on the mechanical, thermal, physicochemical, and microstructural properties and the retrogradation of films obtained by blown film extrusion from thermoplasticized starch with mixtures of glycerol and isosorbide in different ratios (3:0, 2:1, 1:2, and 0:3, respectively). The results showed that the higher concentration of isosorbide significantly increased the tensile strength; however, it reduced the elongation. Retrogradation modeled using the Avrami equation showed that the presence of isosorbide reduced the retrogradation rate (k) and modified the recrystallization mechanism (n). The relative crystallinity in the plasticized TPS films was reduced to 89%, and the adsorption significantly decreased. Isosorbide was very important in reducing the retrogradation of TPS. The best performance was obtained with the 2:1 ratio of glycerol/isosorbide due to the synergistic effect between the plasticizers. The results would allow tuning the properties of TPS films by combining glycerol/isosorbide in different ratios, which enables the design of materials tailored to potential application requirements.

Buckwheat is an important starch source because of its health benefits. In this study, buckwheat starches isolated from 12 varieties were analyzed based on the morphological, structural and physicochemical properties. The results showed that starch samples from different varieties had high purity with the total starch ranging from 91.29 to 95.11%, while showing significant differences in ash content (0.12-0.25%), protein content (0.26-0.34%) and amylose content (29.55-36.13%), respectively. All samples presented spherical and irregular shapes and typical A-type crystalline structure, but obvious differences in granule size distribution and relative crystallinity (26.37-35.21%) were observed among 12 varieties. Starch samples differed in lamellar structures, showing higher values of thickness of the samples with higher amylose content. In addition, buckwheat starches with higher amylose content showed higher values in light transmittance and rheological properties, while starch samples with lower amylose content obtained higher values in terms of water solubility, swelling power, pasting behaviors and thermal parameters. The principal component analysis and cluster analysis based on starch property parameters indicated that there were significant similarities and differences among 12 varieties, which might be related to the genotypes. This study would provide valuable information for the full use of buckwheat starch in food and non-food industries.

Starch retrogradation is a complex process and in most food products is undesirable. Knowing and understanding the mechanisms and factors that influence this process may become the key to a better and innovative approach to food design. In this paper, we investigated the effect of 0%, 0.05% and 0.20% (w/w) xanthan gum (XG) addition on the short- and long-term retrogradation of 4%, 5% and 6% corn starch gels, depending on the amylose/amylopectin ratio in the starch. The changes were monitored throughout 90 days. The pasting characteristics of blends, rheological and texture analyses, as well as syneresis, revealed that XG stabilizes the starch in the short term, but it does not inhibit retrogradation caused by amylopectin. After 30 days of storage, the destabilization of the starch-hydrocolloid mixture was observed. Based on the obtained results, a probable mechanism for the retrogradation of corn starch process in the presence of xanthan gum was proposed.

Heat treatment is used as a pre-processing step to beneficially change the starch properties of wheat flour to enhance its utilisation in the food industry. Heat-treated wheat flour may provide improved eating qualities in final wheat-based products since flour properties predominantly determine the texture and mouthfeel. Dry heat treatment of wheat kernels or milled wheat products involves heat transfer through means of air, a fluidising medium, or radiation—often resulting in moisture loss. Heat treatment leads to changes in the chemical, structural and functional properties of starch in wheat flour by inducing starch damage, altering its molecular order (which influences its crystallinity), pasting properties as well as its retrogradation and staling behaviour. Heat treatment also induces changes in gluten proteins, which may alter the rheological properties of wheat flour. Understanding the relationship between heat transfer, the thermal properties of wheat and the functionality of the resultant flour is of critical importance to obtain the desired extent of alteration of wheat starch properties and enhanced utilisation of the flour. This review paper introduces dry heat treatment methods followed by a critical review of the latest published research on heat-induced changes observed in wheat flour starch chemistry, structure and functionality.

The effects of incorporating polycaprolactone (PCL) in three binary blends with cassava thermoplastic starch (TPS) at TPS/PCL ratios of 60/40, 50/50, and 40/60 were studied. TPS previously obtained by single-screw extrusion was manually mixed with PCL and then transformed by extrusion. The results&rsquo, analysis focused mainly on monitoring the retrogradation phenomenon in TPS for different storage times at two relative humidities (29% and 54%) and constant temperature (25 &deg, C). With the plasticization of the starch, a predominantly amorphous mass was generated, as evidenced by the scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) results. The results suggested that two opposite processes coexisted simultaneously: retrogradation, which stiffened the material, and plasticization, which softened it, with the latter mechanism predominating at short times and reversing at longer times. With the incorporation of PCL, immiscible blends were obtained in which TPS was the dispersed phase, the mechanical properties improved with the amount of PCL added. The properties of the binary blends as a function of time showed a trend similar to that observed for TPS alone, this finding indicated that the TPS/PCL interactions were not strong enough to affect the structural changes in the TPS, which continued to occur regardless of the PCL content. Finally, it was found that for the binary blend, the relative humidity during storage was more significant to the retrogradation phenomenon than the amount of PCL.

Starch is an important source of energy in the human diet with a variety of taste, texture, physicochemical, and organoleptic properties which is greatly influenced by processing methods and additives. Recently, greater attention is directed towards modifying the physicochemical properties of starch using some processing technologies or additives such as sugars, hydrocolloids, proteins, lipids, and other additives with synergistic effects to improve shelf stability and retard starch digestion through a physical barrier, steric hindrance effects or combination. Extrusion process showed greater potential in altering starch physicochemical and digestibility properties, while high hydrostatic pressure and microwave showed some potential but need further investigation. A ternary complex of starch-lipid-protein produces a supramolecular structure which could accommodate bioactive compounds and food sensitive ingredients as a guest in the V-amylose helix or embedded in the ternary structure, further research is needed in this area especially on the digestibility and bioavailability of the embedded compounds.

Retrogradation is defined as the recrystallization or realignment of amylose and amylopectin chains upon cooling of gelatinization starch gels. The storage conditions such as the storage time and temperature are crucial factors that influence and govern the degree of retrogradation and in turn, affect the formation of resistant starch and alteration of thermal and rheological properties. This article investigates the effect of storage time and temperature on the properties of retrograded rice starch. Rice kernels of five different indigenous varieties, namely Diasang lahi, Khaju lahi, Dhusuri bao, Omkar, and Bili rajamudi were cooked by boiling in water and stored at 4 °C and −20 °C for 6 and 12 h, respectively. Differential scanning calorimetry (DSC) studies revealed in raw form that Bili rajamudi exhibited the highest peak gelatinization temperature (Tp, °C) at 79.05 °C whereas Diasang lahi showed the least Tp at 56.12 °C. Further, it was indicated that the Tp and degree of retrogradation (DR%) also increase with increasing time and decreasing temperature of storage. All samples stored at −20 °C for 12 h exhibited the highest degree of retrogradation DR%. Amongst all five varieties stored at −20 °C for 12 h, Omkar exhibited the highest %DR, followed by Bili rajamudi, Khaju lahi, Dhusuri bao, and Diasang lahi. A negative correlation was also established between Tp and resistant starch content (RS%). It was also observed that the resistant starch (RS%) content increased with the increasing time and decreasing temperature of storage. A strong negative correlation was observed between RS% and non-resistant starch (NRS%). Further, rheological studies indicated that retrogradation also affects the viscosity and dynamic rheological properties of starch. In this study, it was evident that extending storage duration from 6 to 12 h and lowering temperature from 4 to −20 °C impact retrogradation of rice starch, which in turn affects the starch’s gelatinization, digestibility, and rheology. Rice starch retrograded at lower temperatures for a longer period could prove to be extremely beneficial for development of food products with better textural properties and high RS content or low glycemic index.

The extent of retrogradation strongly affects certain physical and cooking properties of rice starch (RS), which are important to consumers. In this study, oligomeric procyanidins from lotus seedpod (LSOPC) was prepared and used to investigate its inhibitory effect on RS retrogradation. Various structural changes of RS during retrogradation were characterized by differential scanning calorimetry, low field nuclear magnetic resonance, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The results showed LSOPC could effectively retard both short- and long-term retrogradation of RS, and its inhibitory effect was dependent on the administered concentration of LSOPC. Molecule simulation revealed the interactions of RS and LSOPC, which indicated that the competition of hydrogen bonds between RS and LSOPC was the critical factor for anti-retrogradation. This inhibitory effect and mechanism of action of LSOPC could promote its applications in the field of starch anti-retrogradation.

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Composite films were fabricated by using cellulose nanocrystals (CNCs) as reinforcement up to 50 wt% in thermoplastic starch (TPS). Structure and interactions were modified by using different types (glycerol and sorbitol) and different amounts (30 and 40%) of plasticizers. The structure of the composites was characterized by visible spectroscopy, Haze index measurements, and scanning electron microscopy. Tensile properties were determined by tensile testing, and the effect of CNC content on vapor permeability was investigated. Although all composite films are transparent and can hardly be distinguished by human eyes, the addition of CNCs somewhat decreases the transmittance of the films. This can be related to the increased light scattering of the films, which is caused by the aggregation of nanocrystals, leading to the formation of micron-sized particles. Nevertheless, strength is enhanced by CNCs, mostly in the composite series prepared with 30% sorbitol. Additionally, the relatively high water vapor permeability of TPS is considerably decreased by the incorporation of at least 20 wt% CNCs. Reinforcement is determined mostly by the competitive interactions among starch, nanocellulose, and plasticizer molecules. The aging of the films is caused by the additional water uptake from the atmosphere and the retrogradation of starch.

The pasting properties of starch are influenced by the starch-hydrocolloid interaction in the mixed system. In this study, the effect of pectin extract from three okra genotypes (Agbagoma, Asontem, and Sengavi) at concentrations of 0%, 5%, 10%, and 15% on the pasting properties of starch were investigated. The pasting properties of the mixed systems were determined using the Rapid Visco-Analyzer. The results showed that okra pectin decreased the peak viscosity and setback value of starch with the highest exhibited by Agbagoma and Asontem. The final viscosity of starch was increased in most samples except for 10–15% Agbagoma and 15% Asontem pectin systems. The peak time (3.84 − 6.84 min) increased with increasing okra pectin concentration. Pasting temperature for the mixed systems ranged from 51.24 oC (for 10% Sengavi) to 80.65°C (for 15% Agbagoma). Overall, okra pectin affected the pasting properties of starch and decreased starch retrogradation.

A deposit dated from 40 cal ka bp is interpreted as a remnant of a spodic B horizon exposed on the seabed adjacent to Guanabara Bay at an average depth of 22 m. Bathymetric data, side scan sonar imagery, and underwater images were used to map the expressive feature, never informed before. It is a semi-consolidated muddy-sand deposit with an escarpment up to 4 m and 2.5 km in length (E-W) and 1.5 km in width (N-S). Grain size and geochemical analyses were carried out, and the hypothesis of being formed by podzolization was confirmed. The paleo sea level at the time of the pedogenesis was estimated to be above the maximum height of the global eustatic curves related to Marine Isotopic Stage 3. The feature exhibits a quartzose-sand constitution, defined as an erosion surface exposed at ca. 12 ka bp. The coastal retrogradation of upper unconsolidated sediment during the last transgression contributed to the settlement of a sandbank at the bay mouth.

The effect of Artemisia sphaerocephala Krasch polysaccharide (ASKP) on the gelatinization and retrogradation of wheat starch (WS) was studied. RVA results displayed that ASKP addition increased the setback values of WS, which indicated that ASKP might promote the short‐term retrogradation of WS. DSC and XRD results demonstrated that the retrogradation percentage of WS during long‐time storage significantly decreased with the addition of ASKP, suggesting the inhibition effect of ASKP on the long‐term retrogradation of WS. As shown in TPA test, ASKP addition increased the hardness of starch gel at the beginning but decreased it after 14 days’ storage. Results of FT‐IR revealed that ASKP could promote the water retention and intermolecular hydrogen bonding formation. With the addition of ASKP, the spin–spin relaxation time measured by LF‐NMR decreased from 358.47 ms to 274.15 ms, illustrating that the WS paste containing ASKP had higher water retention ability. Leached amylose content results manifested the interaction between WS and ASKP. In summary, ASKP has potential to be a modifier on the retrogradation of starch in food processing., ASKP has the ability to accelerate the short‐term retrogradation of WS but decelerate the long‐term process. ASKP has potential to be a modifier on the retrogradation of starch in food processing.

Amylose (AM) and amylopectin (AP) functionality during bread making was unravelled with a temperature-controlled time domain proton nuclear magnetic resonance (TD 1H NMR) toolbox. Fermented doughs from wheat flour containing starches with atypical AP chain length distribution and/or AM to AP ratio, or supplemented with Bacillus stearothermophilus α-amylase (BStA) were analyzed in situ during baking and cooling. The gelatinization temperature of starch logically depended on AP crystal stability. It was lower when starch contained a higher portion of short AP branches and higher when starch had higher AP content. During cooling, the onset temperature and extent of AM crystallization were positively related to starch AM content. BStA use resulted in slightly weakened starch networks and increased the starch polymers' mobility at the end of baking. That proton distributions evolved in a way corresponding to starch characteristics supports the suggested interpretation of NMR profiles during baking and cooling. ispartof: FOOD CHEMISTRY vol:295 pages:110-119 ispartof: location:England status: published

In this work, the effects of relative humidity (RH) pre-conditioning (53% vs. 85% RH) and incorporation of cellulose fillers (from Posidonia waste biomass) on the properties and retrogradation of melt compounded starch biocomposites were investigated. Pre-conditioning at 85% RH promoted starch gelatinization during processing, leading to more amorphous materials with reduced stiffness but better barrier properties. Furthermore, these films were less stable upon storage due to greater starch retrogradation. Cellulose incorporation improved significantly the mechanical and water barrier performance, especially in the films pre-conditioned at 85% RH due to enhanced filler dispersion. Although incomplete gelatinization of the starch pre-conditioned at 53% RH led to films with bigger cellulose aggregates, their mechanical and water barrier properties were better, outperforming starch-cellulose biocomposites typically reported in the literature. Moreover, the presence of cellulose limited the degree of starch retrogradation upon storage, highlighting the potential of Posidonia biomass as a cheap source of high-performance fillers., This work was financially supported by the project GV/2018//149, the “Agencia Estatal de Investigación” and co-funded by the European Union’s Horizon 2020 research and innovation programme (ERA-Net SUSFOOD2). Marta Martinez-Sanz is recipient of a Juan de la Cierva (IJCI-2015-23389) contract from the Spanish Ministry of Economy, Industry and Competitiveness.

It is necessary to expand knowledge regarding physical environment in order to establish rational guidelines for coastal areas use, thus, this research aimed to determine retrogradation rates and vulnerability of the seashore at Barra de São Miguel county to RSL rise, as well as to suggest building zone limits. Therefore, in loco environmental observations were obtained between 2016 and 2017. In order to categorize vulnerability level, the coast was divided into section A (A1, A2 e A3) and section B. Results show that approximately 57% of the coast (Section A) is threatened, presenting high vulnerability level. In contrast, section B presented low erosion vulnerability. Retrogradation indicated that even in the optimistic scenario, retreats will be high, reaching all buildings in the section A. Section B, despite high environmental preservation level, would still exhibit retreats of 15.1m. Coastal building zone limit (CBZL) demonstrated that previous results adoption would be enough to absorb future impacts generated by RSL rise. Thus, it is valid to affirm that results obtained are important to comprehend coastal environment and could be used as a guiding source to monitoring and management of the region.

Starch is widely used in food and non-food industries because of its unique characteristics. However, native starch shows some weaknesses that restrict its applications. Recently, some studies have demonstrated the benefits of using protein to overcome these limitations. Therefore, the aim of the present study was to investigate the effect of mung bean protein isolate (MBPI) (2%, 4%, 6%, and 8%) on the physicochemical, pasting, and thermal properties of native corn starch (NCS), as a novel starch–protein composite. Higher swelling power (SP), water absorbance capacity (WAC), and solubility values of NCS were observed with increasing MBPI concentration. Additionally, by the addition of MBPI, the rapid visco analyzer (RVA) showed a reduction in pasting temperature (77.98 to 76.53 °C), final viscosity (5762 to 4875 cP), and setback (3063 to 2400 cP), while the peak viscosity (4691 to 5648 cP) and breakdown (1992 to 3173 cP) increased. The thermal properties of NCS/MBPI gels investigated by differential scanning calorimetry (DSC) showed higher onset, peak, and conclusion temperatures (69.69 to 72.21 °C, 73.45 to 76.72 °C, and 77.75 to 82.26 °C, respectively), but lower gelatinization enthalpy (10.85 to 8.79 J/g) by increasing MBPI concentration. Fourier transform infrared spectroscopy (FT-IR) indicated that the addition of MBPI decreased the amount of hydrogen bonds within starch. Furthermore, after three cycles of freeze-thaw shocks, the syneresis of NCS-MBPI composites decreased from 38.18 to 22.01%. These results indicated that the MBPI could improve the physicochemical properties of NCS, especially its syneresis and retrogradation characteristics.

The effect of konjac glucomannan (KGM) on the retrogradation of amylose was explored during storage. The color, rheological properties, texture, water-holding capacity (WHC), low-field nuclear magnetic resonance (LF-NMR), and X-ray diffraction (XRD) were investigated. Results of color and rheological measurements showed that with the increasing amount of KGM, the L value of the system decreased, but the elastic modulus, viscous modulus, and tangent value of loss angle increased. The textural result presented that KGM obviously inhibited the growth rate of gel strength of amylose. Results from WHC and XRD suggested after 14 days of storage, when the concentration of KGM increased from zero to 0.3% in the mixture, the WHC grew from 80% to 95% and the crystallinity degree declined from 35.3% to 25.6%. The LF-NMR result revealed that KGM limited the conversion of free water to bound water in the system. In general, a small amount of KGM in a mixed system could inhibit the short-term and long-term retrogradation of amylose. This research could provide a theoretical reference for the influence of hydrophilic colloids on the retrogradation of starch, and it could also provide support for the processing and production of starch-based food.

Highlights • Sonication induced a partial depolymerization of starch molecules. • Sonication treatment induced the appropriate structural changes for retrogradation. • The degree of retrogradation degree was not affected by sonication. • Retrogradation rate was greater in sonicated starch than in non-sonicated starch., In this study, the effects of sonication and temperature-cycled storage on the structural properties and resistant starch content of high-amylose corn starch were investigated. Sonication induced a partial depolymerization of the molecular structures of amylopectin and amylose. Sonication treatment induced the appropriate structural changes for retrogradation. Although the relative crystallinity of sonicated starch was lower than that of non-sonicated starch, sonicated starch after retrogradation showed much higher relative crystallinity than non-sonicated starch. Regardless of sonication treatment, temperature-cycled storage resulted in a higher degree of retrogradation than isothermal storage, but the rate of retrogradation was greater in sonicated starch than in non-sonicated starch, as supported by retrogradation enthalpy, the Avrami constant, and relative crystallinity. The highly developed crystalline structure in sonicated starches due to retrogradation was reflected by the large amount of resistant starch.

The aim of this study was to evaluate the effect of the temperature (15 or 45 °C) and the duration (15–120 min) of the modification process on the selected physicochemical, thermal, and rheological properties of phosphorylated potato starch. The modified starches contained 93.6–98.2 mg P/100 g (dry weight basis, d.w.b.). Phosphorylation caused color changes with a total color difference between the starches below 0.55, but these changes were less than those that were recognizable by the human eye. The thermal analysis showed two opposite processes appearing during the modification: the loosening of the structure (dominant among starches obtained at 15 °C) and the strengthening of the structure (dominant among starches obtained at 45 °C). The higher phosphorylation temperature reduced native starch recovery from 140% to 87–116% and increased the hysteresis loop area from −169 to 1040. All of the pastes made from the modified starches showed a weaker tendency for retrogradation (during 21 days of storage) than native starches. The results of the regression analysis conducted between the properties of the starch pastes obtained at 45 °C indicated that the modification time appeared to be a better indicator of the rate of modification progress than the phosphorus content. The PCA (principal component analysis) results made it possible to distinguish starch phosphates obtained at 15 °C from those obtained at 45 °C and those from natural starch.

Using the method of dynamic–mechanical analysis, the structuralisation kinetics of condensed starch solutions, cooled down to the temperature of 20 °C, was investigated. A close correlation of spatial crosslinking with local processes of macromolecule associations was discovered. It was found that depending on the concentration intervals of starch solutions, equilibrium nodes of the spatial network assume the form of either single or double hexagonal structures made up of bispiral chain associates. The increase of gel crosslinking, together with the passage of time, is the result of increasing the node functionality of the spatial network.

The effects of three types of polymeric proanthocyanidins (PPC) with different degrees of polymerization (DP), namely PPC1 (DP = 6.39 ± 0.13), PPC2 (DP = 8.21 ± 0.76), and PPC3 (DP = 9.92 ± 0.21), on the physicochemical characteristics and in vitro starch digestibility of potato starch were studied. PPC addition (5%, w/w) increased the gelatinization temperature and decreased some viscosity indices of potato starch, including the peak, trough, breakdown, and setback viscosities. Starch-PPC pastes showed reduced thixotropy and improved stability and gelling properties compared to starch paste. The three types of proanthocyanidins all showed evident inhibitory effects on the digestion and retrogradation of potato starch, including short-term and long-term retrogradation. Among the three, PPC with a lower DP had stronger effects on the starch short-term retrogradation and gelling performance, whereas larger PPC molecules exhibited a greater impact on starch recrystallization and digestive characteristics. The research consequences were conducive to explore the application of functional PPC in starch-based food processing.

In the baking industry, different processes and methods of freezing have been used for breadmaking to preserve a quality comparable to that of fresh bread. In this study, the effect of part-baking time, freezing rate, and frozen storage time on part-baked French bread quality was determined. The bread was part-baked for 0, 3 and 6 min, frozen at slow (0.15 °C/min) and fast (1.75 °C/min) freezing rates, stored under freezing conditions for up to 56 days and thawed every 14 days. Part-baked bread was rebaked, and the SV and firmness at 2, 24 and 48 h were obtained. An experiment with a factorial design of 3×2×5 (3 part-baking time, 2 freezing rates and 5 frozen storage times) with analysis of variance (ANOVA) at a confidence level of 95% was carried out. The highest SV was ​​obtained at 6 min of part-baking at a slow freezing rate and decreased as the frozen storage time increased. In contrast, TPA showed that bread firmness increases when the specific volume decreases, and the highest firmness is at 0 min of part-baked time. Relatively long part-baking times allow for firm crumb formation with limited damage to the structure and therefore bread with optimal quality.

Slowly digestible starches have received interest due to their lower increase of postprandial blood glucose and insulin levels and, hence, modification of starches towards slower digestibility has commercial interest. However, chemical characteristics driving enzymatic (digestive) degradation are not fully unraveled. The digestion properties of starches have been linked to their crystalline type, chain length distribution, amylose content or degree of branching, but content and length of relatively long side-chains in amylopectin has not been paid attention to. Therefore, this research focusses on the unique content and length of amylopectin side-chains from conventional and new starch sources (potato, corn, pea, and tulip) correlated to the enzymatic digestion. The rate of hydrolysis was found to be correlated with the crystalline type of starch, as previously suggested, however, the complete hydrolysis of all starches, independent of the crystalline type and source, was shown to be governed by the content of longer amylopectin chains.

The Cananeia-Iguape lagoon-estuarine system, where the Ilha Comprida barrier (IC) is located, is one of the most dynamic coastal areas on the southeastern Brazilian coast. IC island is a 63 km-long barrier and it is limited by the Icapara inlet to the north, and the Cananeia inlet to the south. This system has been affected by intense changes in its morphology since the opening of the Valo Grande artificial channel in 1852 A.D., connecting the nearby Ribeira de Iguape river to the Mar Pequeno lagoon. In this context of anthropogenic disturbance on the coastal systems, the objective of this study is to understand the active mechanisms, both natural and anthropogenic, controlling the morphological changes of the northeastern portion of the IC, from monthly as well as centenary timescales. We analyzed successional addition and erosion of beach ridges using a multi-temporal dataset obtained by Optically Stimulated Luminescence, aerial photos (1962 and 2000), satellite images (1980-2016) and GNSS surveys (2015-2017). The results were compared to climatic (rainfall and waves) data. Northeastward migration rates of the IC ranged from 15.5 m/y, on the GNSS surveys, to 154 m/y, calculated based on OSL rates. Changes on rates on the northeastward inlet migration barrier are related to anthropogenic interference, mainly the Valo Grande opening and climate changes. Sediment accumulation occurred mainly during the summer on the baymouth spits. This depositional scheme is consistent with the highest values of Ribeira de Iguape river flow and the low synergy of waves coming from the South. By contrast, the retrogradation of the coastline occurs in the winter, when the wave power is stronger than in the summer. This seasonal configuration is controlled both by the bidirectional longshore drift and by the fluvial discharge.

Deltas generally exhibit morphological and architectural variations due to repercussions of fluvial, wave and tidal currents. The Neoproterozoic Chhaosa Formation, Simla Group, Lesser Himalaya, a shallow-marine, mixed-energy deltaic system represents a unique example of variability of those processes at different scales. Outcrop-based facies analysis was combined with application of sequence stratigraphy in the present study to elucidate signatures of fluvial, tide and wave currents. The proximal part of the delta plain deposits (FA1) displaying fluvial attributes like sand sheets, large and small scale trough cross-beddings, channels, are combined with tidal activity. Delta front (FA2) deposits and prodelta deposits (FA3) essentially record mixed tidal and wave activity like mud drapes, flasers, lenticular, wavy beddings, syneresis cracks, tidal rhythmites, low angle cross-stratification oscillation ripples, hummocky and swaley cross-stratifications. Coastal process classification ternary plots are prepared to identify the interplay of different processes and their control in the deposition of Chhaosa delta system. The Chhaosa Formation has developed during elevated pulse rates of progradation and retrogradation, overlapped with elongated phases of progradation. A comparison between the Chhaosa delta and modern as well as ancient delta system has been made to understand the control of mixed-energy processes on sedimentation patterns throughout the global history.

The Pearl River Mouth Basin is located at the northern continental shelf of the South China Sea. Since the early Miocene, the Paleo-pearl river transported a large amount of sediments to the northwest of the basin and resulted in the formation of a large-scale river-delta depositional system, which has become an important oil and gas reservoir in the study area. In the current paper, we investigate the characteristics and evolution of fluvial-deltaic depositional systems and their controlling factors, including sea level change, tectonic subsidence and sediment supply on the basis of 3D seismic, well logging and core data. Early-Mid Miocene succession can be divided into two second-order sequences (CS1–CS2) and eight third-order sequences (S1–S8). Deltaic systems developed in S1–S2 are relatively coarse in grain size, and the delta plain deposits are dominated by thickly stacked (100–180 m) distributary channel sand bodies and interpreted as braided delta depositional system. In the early stage (S1–S2), the braided delta systems mainly distributed in the west of the Baiyun Sag, which were proceeded by a retreat to the south of the Enping Sag along with sharply rising sea level. Following the transgression of S2, the provenance of the Paleo-Pearl River extended to the coastal region of South China, and the papleoclimate changed from warm and humid to dry and cold in the early Miocene, leading to the development of transition of braided river delta to meandering river delta, which was characterized by relatively fine grain deposits. During the deposition of S3–S6, well sorted and rounded fine sandstones of deltaic front deposits accumulated in the study area. The retrogradation to accretion and subsequent progradation of these meander delta systems are attributed to the sea level change in the study area. During the deposition of S7–S8, the delta front retreated to the south of the Enping depression as a result of minor sea level rise, reduction in sediment input, and subsidence rate. This resulted in the development of a wave-controlled deltaic depositional system.

The ability of agar with different purification degrees to produce packaging films has been evaluated and the stability of the obtained materials after prolonged storage has been investigated. The less purified agar resulted in films with higher water vapor permeability and lower mechanical performance than pure commercial agar. However, the commercial agar film required the addition of a plasticizer to produce films that could be manipulated. It has also been observed that prolonged storage at 53 % RH results in a change in the semi-crystalline structure of the agar and in water-polysaccharide interactions. As a result, pure agar films undergo a rigidizing effect resulting in unmanageable films after 7 days of storage. The presence of glycerol improved the stability of the films by limiting the structural changes up to 14 days of storage. In contrast, the films from the least purified agar extract, seemed to be less affected by moisture, showing a higher stability during storage. This points to the potential of the less purified extract to be used as an additive to reduce costs and improve the storage stability of pure agar films., This work was financially supported by Hispanagar.

Recently, hybrid fillers have been widely used to improve the properties of biopolymers. The synergistic effects of the hybrid fillers can have a positive impact on biopolymers, including thermoplastic corn starch film (TPCS). In this communication, we highlight the effectiveness of hybrid fillers in inhibiting the aging process of TPCS. The TPCS, thermoplastic corn starch composite films (TPCS-C), and hybrid thermoplastic corn starch composite film (TPCS-HC) were stored for 3 months to study the effect of hybrid filler on the starch retrogradation. TPCS-C and TPCS-HC were prepared by casting method with 5 wt% of fillers: nanocellulose (NC) and bentonite (BT). The alteration of the mechanical properties, aging behavior, and crystalline structure of the films were analyzed through the tensile test, Fourier transform infrared (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and water absorption analysis. The obtained data were correlated to each other to analyze the retrogradation of the TPCS, which is the main factor that contributes to the aging process of the biopolymer. Results signify that incorporating the hybrid filler (NC + BT) in the TPCS/4BT1NC films has effectively prevented retrogradation of the starch molecules after being stored for 3 months. On the contrary, the virgin TPCS film showed the highest degree of retrogradation resulting in a significant decrement in the film’s flexibility. These findings proved the capability of the green hybrid filler in inhibiting the aging of the TPCS.

High-protein rice is nutritional, but its taste attributes are inferior to low-protein rice. Many documents correlate its taste attributes with its gelatinization and retrogradation properties. This study investigated the changes in gelatinization and retrogradation properties of low- and high-amylose reconstituted rice flour (RRF) added with different fractions of proteins extracted from high-protein rice. The addition of protein decreased the RVA (rapid viscosity analyzer) viscosity parameters of the RRF but increased the peak time. The high amylose fractions in the RRF mainly increased the parameters PV, FV, SB, and peak times, and scarcely affected the parameters BD and PaT. The interaction between amylose and protein determined the pasting temperature. Protein addition in RRF significantly decreased gelatinization enthalpies but increased the onset temperature (To) and peak temperature (Tp), while the amylose in RRF increased the gelatinization enthalpies, To and Tp. Protein additions decreased the gel hardness and the pore size, while the amylose increased the gel hardness but decreased pore size. Our findings may be potentially useful in breeding and cultivating high-protein rice.

ilustraciones, diagramas, tablas Las bebidas lácteas fermentadas son productos generalmente elaborados a partir de leche entera los cuales suelen incluir suero de leche liquido en su formulación, lo que afecta negativamente su consistencia. En la producción de bebidas lácteas fermentadas los almidones modificados son comúnmente empleados como estabilizantes y espesantes. El creciente interés en productos de características más “naturales” ha incrementado la importancia de métodos de modificación de almidón alternos a la modificación química. Las propiedades térmicas y de empastamiento de dos almidones modificados enzimáticamente empleando Pululanasa (PUL) y amiloglucosidasa (AGL) fueron estudiadas y comparadas con un almidón modificado químicamente (ADA). Una formulación óptima para la elaboración de las bebidas fue determinada mediante un diseño de superficie de respuesta empleando el almidón ADA, y fue posteriormente empleada para la elaboración y análisis de bebidas preparadas con almidones modificados enzimáticamente. Bebidas lácteas con adición de los almidones modificados enzimáticamente (PUL y AGL) fueron elaboradas y sus características fisicoquímicas, reológicas y sensoriales fueron evaluadas y contrastadas con bebidas elaboradas con almidón modificado químicamente (ADA), bebidas control sin adición de almidón y una muestra comercial en un periodo de 20 días de almacenamiento. Las bebidas elaboradas con almidón modificado enzimáticamente presentaron niveles significativamente mayores de viscosidad, consistencia, aceptabilidad sensorial, y valores de sinéresis significativamente menores que los de las bebidas control, resultados comparables a los obtenidos con el tratamiento ADA. Los almidones AGL mostraron altos niveles de retrogradación (35.04%), lo cual pudo haber afectado negativamente la viscosidad, consistencia, sinéresis y aceptabilidad de las bebidas al final del periodo de almacenamiento. La modificación enzimática del almidón de yuca con Pululanasa muestra un gran potencial como alternativa a los almidones modificados químicamente en la producción de bebidas lácteas fermentadas. (texto tomado de la fuente) Fermented dairy beverages are products generally elaborated from whole milk with the inclusion of liquid whey, which can negatively impact the consistency of the product. In the production of fermented dairy beverages, modified starches are commonly used as stabilizers and thickeners. The growing interest in products with more “natural” characteristics has increased the relevance of modification methods different from chemical modification. The thermal and pasting properties of two enzymatically modified starches, one modified with Pullulanase (PUL) and another modified with Amyloglucosidase (AGL), were studied and compared with a chemically modified starch (ADA). An optimal formulation for the production of fermented dairy beverages was determined through a response surface method using the ADA starch, which was later used for the production and analysis of beverages with enzymatically modified starches. Fermented dairy beverages with the inclusion of enzymatically modified starches (PUL y AGL) were elaborated and evaluated with respect to its physicochemical, rheological, and sensory characteristics, and compared to beverages with chemically modified starch (ADA), control beverages without the addition of starch and a commercial sample in a 20 days storage period. Beverages with enzymatically modified starches showed significantly higher levels of apparent viscosity, consistency, sensory acceptability, and significantly lower values of syneresis in comparison to those of the control beverages, similar results to those obtained with chemically modified starch (ADA). AGL starches showed high levels of retrogradation (35.04%), which could have negatively affected the viscosity, consistency, syneresis, and acceptability of the beverages at the end of the storage period. The enzymatic modification of cassava starch with Pullulanase shows great potential as an alternative to chemically modified starches for the production of fermented dairy beverages. POLTEC SAS Maestría Magister en Ciencia y Tecnología de Alimentos Los resultados de las propiedades de calidad de las bebidas (porcentaje de sinéresis, pH, acidez titulable, consistencia, viscosidad y tamaño de partícula) fueron analizados mediante un análisis de varianza (ANOVA) y las medias comparadas con un test de Tukey (P ≤ 0.05). El análisis estadístico fue realizado en el programa Minitab (Minitab Inc. USA) y los resultados fueron expresados como la media ± la desviación estándar. Ciencia y Tecnología de Alimentos Área Curricular en Ingeniería Agrícola y Alimentos

Gummy confections are popular products formulated with sucrose, glucose syrups, gelling agents, acids, flavourings and colouring agents. They have various commercial types in terms of formulation, texture, taste and colour, however, there is inadequate investigation on storage behavior of these products. The aim of this study is to investigate the effects of glucose syrup:sucrose ratio (1.1 and 1.5), starch (0% and 1.5%) and gelatine concentration (3% and 6%) on texture profile, colour and sensory properties of gummy confections during storage. It was also aimed to correlate sensorial changes with physical properties measured by instrumental techniques during storage at 10 degrees C, 20 degrees C and 30 degrees C. The highest increase in hardness was observed for formulation with 1.1 glucose syrup:sucrose ratio, no starch and 6% gelatine. Storage temperature had no significant effect on cohesiveness. It was seen that rate of colour change increased with storage time and temperature. Formulation with glucose syrup:sucrose ratio of 1.5, no starch and 6% gelatine had the highest sensory scores. This formulation was found to be the most stable formulation in terms of hardness and gumminess, meaning that it would need a stable mastication during storage. Sensorial changes of gummy confections were found to be correlated with instrumental results of texture and colour. Kervan Gida San. ve Tic. A. S. (Istanbul, Turkey) The authors kindly thank to Kervan Gida San. ve Tic. A. S. (Istanbul, Turkey) for their supports to this study.

The application of exogenous plant growth regulator can improve plant resistance to drought stress. The effects of application of exogenous cytokinin (CTK), brassinolide (BR), or gibberellic acid (GA) at the silking time on the grain quality of two waxy maize hybrids under drought stress at grain formation stage were studied. Grain weight of both hybrids was unaffected by exogenous phytohormones under control conditions but increased under drought conditions with the application of BR. The grain starch content in response to drought varied with hybrid and phytohormone. Starch granule size and protein content in grains were increased by drought under all conditions, but various phytohormones exerted different forms of influence. The starch &lambda, max in Yunuo7 was unaffected by single or interaction of phytohormones and water deficit, &lambda, max in Jingkenuo2000 with BR was unaffected but with CTK or GA increased by drought. Relative crystallinity was reduced by drought without the application of phytohormone, but with phytohormones in response to drought it was different. Flour peak viscosity was reduced by drought. The value was increased with BR spraying under control and drought conditions. Retrogradation percentage under drought conditions was unaffected by exogenous phytohormones in Jingkenuo2000. In Yunuo7, retrogradation percentage was unaffected by BR but reduced by CTK and GA. In conclusion, spraying phytohormones at the silking stage can affect grain weight and starch quality, grains with a sticky taste can be improved by applying BR, and grains with low retrograde tendency can be produced by applying CTK.

The main energy reserve in plants is starch. It is unique among polysaccarides for being in the form of granules. Starch granules are heterogeneous mixtures of amylose and amylopectin. Gelatinization and retrogradation of starch depend on the ratio of amylose to amylopectin, type of crystallinity, along with the sizes and structure of starch granules. The present work determined the rheological behavior in a dynamic state, in terms of sweeping frequency, time and temperature, in addition to the extrusion of corn starch gels and arrowroot and cassava starches. The rheological study demonstrated that in all samples analyzed, whether in a non-gelatinized liquid mixture or in the form of gels, behaved as non-Newtonian fluids independent of time. Non-gelatinized mixtures showed properties of dilating non-Newtonian fluids and the gels of pseudoplastic non-Newtonian fluids. Gels were classified as elastic, as it was found that the storage module is larger than the dissipation module with the storage module decreasing with increasing temperature, and thus temperature dependent. With increased temperature, the gels showed low stability which is characteristic of weak gels. The more elastic the gel, the greater its resistance and the corn starch gel was the most resistant when compared to arrowroot and cassava starch. La principal reserva energética de las plantas es el almidón, siendo abundante en semillas, raíces y tubérculos. De todos los polisacáridos, el almidón es el único que se produce en pequeños agregados individuales, llamados gránulos. Los gránulos de almidón son mezclas heterogéneas de dos macromoléculas, amilosa y amilopectina, que difieren en tamaño molecular y grado de ramificación. Las propiedades de gelatinización y retrogradación del almidón están relacionadas con varios factores, incluida la proporción de amilosa y amilopectina, el tipo de cristalinidad, el tamaño y la estructura del gránulo de almidón. Así, el objetivo de este trabajo fue determinar el comportamiento reológico en estado dinámico, en términos de frecuencia de barrido, tiempo y temperatura, además de la extrusión de geles de almidón de maíz y almidones de arrurruz y yuca. Se demostró mediante el estudio reológico que todas las muestras analizadas, al estar en una mezcla líquida no gelatinizada o en forma de geles, presentaban características de fluidos no newtonianos independientes del tiempo. Las mezclas no gelatinizadas mostraron propiedades de dilatación de fluidos no newtonianos y los geles de fluidos pseudoplásticos no newtonianos. Los geles se clasificaron como elásticos, ya que se encontró que el módulo de almacenamiento es más grande que el módulo de disipación y, dependiendo de la temperatura, disminuye con su aumento. Se concluyó que con el aumento progresivo de temperatura, los geles mostraron baja estabilidad, característica de los geles débiles. Cuanto más elástico es el gel, mayor es su resistencia, y el gel de almidón de maíz es más resistente en comparación con el almidón de arrurruz y yuca. A principal reserva de energia nas plantas é o amido, sendo abundante em sementes, raízes e tubérculos. De todos os polissacarídeos, o amido é o único produzido em pequenos agregados individuais, denominados grânulos. Os grânulos de amido são misturas heterogêneas de duas macromoléculas, amilose e amilopectina, que diferem no tamanho molecular e grau de ramificação. As propriedades de gelatinização e retrogradação do amido estão relacionadas a vários fatores, incluindo proporção de amilose e amilopectina, tipo de cristalinidade, tamanho e estrutura do grânulo de amido. Desta forma, o objetivo deste trabalho foi determinar o comportamento reológico em estado dinâmico, quanto à varredura de frequência, tempo e temperatura, além da extrusão dos géis de amido de milho e féculas de araruta e de mandioca. Demonstrou-se através do estudo reológico que todas as amostras analisadas, sendo em mistura líquida não gelatinizada ou em forma de géis, apresentaram características de fluidos Não-Newtonianos independentes do tempo. As misturas não gelatinizadas apresentaram propriedades de fluídos Não-Newtonianos dilatantes e os géis de fluidos Não-Newtonianos pseudoplásticos. Os géis foram classificados como elásticos, pois verificou-se que o módulo de armazenamento é maior que o módulo de dissipação e dependentemente da temperatura, decresce com o seu aumento. Concluiu-se que com o aumento progressivo da temperatura, os géis apresentaram baixa estabilidade, característica de géis fracos. Quanto mais elástico é o gel, maior será a sua resistência, sendo que o gel de amido de milho foi mais resistente quando comparado às féculas de araruta e de mandioca.