Native Potato Research Articles

Assessment of In Vitro Antioxidant Activity and Phenolic Composition in Peels of Ten Native Potato Cultivars from Cusco

Assessment of In Vitro Antioxidant Activity and Phenolic Composition in Peels of Ten Native Potato Cultivars from Cusco

A biodegradable bi‐layer nano fibrous membrane fabricated by centrifugal spinning for active food packaging

AbstractTo solve the problem of cytotoxicity for most antimicrobial agents loaded in packaging materials, we developed a novel bi‐layer fibrous membrane by using centrifugal spinning, which of the outer layer was submicron native potato starch/polyvinyl alcohol (ST/PVA) composite fibers loaded with ZnO nanoparticles (ZnO NPs) for providing high antibacterial activity. The inner layer was nano‐based calcium alginate/polyethylene oxide (CA/PEO) fiber for providing excellent biocompatibility. The addition of ZnO caused the semicrystalline structures of ST/PVA fibers, while the CA/PEO fibers were shown semicrystalline structures due to the PEO. Fourier transform infrared indicated that posttreatment had not effect on the structures of ST/PVA/ZnO fiber, but the structure of CA/PEO fibers were affected by interaction between COO groups of alginate and Ca2+ ions. The results of mechanical property demonstrated that CA/PEO fibers showed highest stress of 3.83 ± 0.25 MPa and helpful for improving the stress of bi‐layer fibrous membrane. The obtained fibrous membrane had excellent antibacterial property with diameters of bacteriostatic zone against E. coli and S. aureus of 20.5 and 21.5 mm, respectively. On this basis, the shelf life of strawberry was improved up to 6th day by inhibit the growth of microorganisms, which indicated that the obtained fibrous membrane showed great potential for food packaging.

Using Eco-Friendly Nano-Polymers in Industrial Wastewater Treatment

Abstract The major target of this research is to synthesize an eco-friendly coagulant, based on a biomaterial (potato starch) that contribute in industrial wastewater treatment. From this work an eco-friendly nano-polymer was produced from potato starch. Successfully not only the potatoes were used, but also the potato peel, which has an economic impact on reducing the amount of water wasted in planting such an important crop as the potatoes all over the world. Because of increasing the need for food production and changing the dietary pattern, the development of potato industry has become the first among all food crops in most of the countries. As a result potato starch became the most popular type among the polysaccharides. To achieve this, the experimental work started by extracting the starch from the potato and potato waste (peels). In order to enhance the potato starch characteristics, the synthesis of starch nano-particles (StNPs) was conducted by gelatinization using a mixture of sodium hydroxide along with glycerol in aqueous medium throughout the reaction process, while settling down the StNPs which was done by homogenization at ambient temperature. Characterization was done on both native potato starch and starch nano-particles using Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Energy Dispersive X-ray Spectroscopy (EDX). The second part of the experimental work is to test the eco-friendly starch nano-particles (starch-based coagulants) in industrial wastewater treatment, and to evaluate its effectiveness as a coagulant against the most commonly used synthetic polymer (PolyDADMAC) playing the same roll in industry and whether it can really replace it or not.

Development of Edible Films Based on Nostoc and Modified Native Potato Starch and Their Physical, Mechanical, Thermal, and Microscopic Characterization.

Considering the potential of biopolymers from underutilized Andean sources in Peru to improve the characteristics of edible films, this work aimed to evaluate the formation of a polymeric matrix composed of Nostoc and modified potato starch for the formulation of edible films for food coating. The effects of polymer matrix ratio and drying temperature on films obtained by thermoforming were studied, determining the water vapor permeability and mechanical properties using a multifactorial design. Additionally, thermal properties were characterized by TGA and DSC, and structural properties by FT-IR and scanning electron microscopy. The results showed that the films exhibited lower solubility, lighter hues, better water vapor resistance, higher tensile strength, and improved thermal stability with increasing modified starch content. The formulation with higher Nostoc content exhibited a more homogeneous surface according to microscopy images, and no new chemical bonds were formed by adding modified starch and Nostoc to the polymer matrix, according to FT-IR spectra. These findings are promising and suggest using Nostoc for elaborating edible films composed of native and modified starch from native Andean potatoes as bio-based materials with potential application in the food industry.

Antitumor properties of colored native potatoes (Solanum tuberosum ssp. tuberosum) from southern Chile

Breast cancer is one of the most diagnosed neoplasms worldwide, especially in women. The disease occurs due to genetic variations that modify cell behavior in various cellular aspects, increasing proliferation and preventing cell death among them. Breast cancer presents an average response rate to conventional treatments of between 50% and 60%, given that in the long term, it may present natural or tumor-acquired resistance ar. Diets that include foods that contribute to enhance the molecular mechanism of anti-tumoral medications or stop the development of tumor recurrence, could be important in improving patient survival. Among foods with antitumor biological activities such as antiproliferative or antioxidant activity, those with high phenolic content and a purple color have gained prominence in recent years. In the present research, it has been found that purple and pink-colored Chilean native potato genotypes possess high concentrations of total phenolic content and anthocyanins. The results showed that the potato extract modified the antioxidant response of breast cancer cells. Additionally, three high-pigmented potatoes induce significant cell death in two different breast cancer cell lines. As a molecular mechanism, the extract with high anti-tumoral activities can modulate the gene expression of Bax and Bcl-2, both associated with cell death. In summary, the results demonstrate the important biological activities of native potato genotypes on breast cancer cell viability. It is important to highlight the great biomedical potential of these potatoes, which could be cultivated extensively, be used worldwide for nutrition and may be an excellent complementary option for patients undergoing breast cancer treatments.

Effect of ultrasonically stimulated potato germination during soaking on the physicochemical properties of starch and its use in edible films

The aim of this work was to investigate the effects of ultrasonic treatment during soaking of potatoes on the physicochemical properties of starches obtained after 16 weeks of germination. The ultrasonic treatment showed a direct correlation between sprout length and ultrasonic time. The protein content decreased from 0.63 to 0.38 % and the fat content decreased significantly from 0.31 to 0.01 % after germination. The amylose content changed depending on the ultrasonic treatment, and increased from 36.27 to 40.92 % after 16 weeks of germination, which was related to the amylopectin debranching and the duration of the ultrasonic treatment. X-ray diffraction showed that the nanocrystals with hexagonal structure were not affected by the germination and the duration of ultrasonic treatment. Scanning electron microscopy showed that the surface of the starch granules was not affected by the enzymatic treatment.The sprouted potato starch resulted in films with better tensile strength and lower water vapor permeability (WVP) compared to the native potato starch films. In addition, the films produced with ultrasound stimulated potato starch exhibited better properties (high strength and low permeability), which is desirable when it comes to controlling moisture exchange between a food product and the surrounding atmosphere.

The impact of Cas9-mediated mutagenesis of genes encoding potato starch-branching enzymes on starch structural properties and in vitro digestibility

The digestibility of starch is affected by amylose content, and increasing amylopectin chain length which can be manipulated by alterations to genes encoding starch-branching enzymes (SBEs). We investigated the impact of Cas9-mediated mutagenesis of SBEs in potato on starch structural properties and digestibility.Four potato starches with edited SBE genes were tested. One lacked SBE1 and SBE2, two lacked SBE2 and had reduced SBE1, and one had reduced SBE2 only. Starch structure and thermal properties were characterised by DSC and XRD. The impact of different thermal treatments on digestibility was studied using an in vitro digestion protocol.All native potato starches were resistant to digestion, and all gelatinised starches were highly digestible. SBE modified starches had higher gelatinisation temperatures than wild type potatoes and retrograded more rapidly. Gelatinisation and 18 h of retrogradation, increased gelatinisation enthalpy, but this did not translate to differences in digestion. Following 7 days of retrogradation, starch from three modified SBE starch lines was less digestible than starch from wild-type potatoes, likely due to the recrystallisation of the long amylopectin chains. Our results indicate that reductions in SBE in potato may be beneficial to health by increasing the amount of fibre reaching the colon after retrogradation.

Differentiation between Hydrolytic and Thermo-Oxidative Degradation of Poly(lactic acid) and Poly(lactic acid)/Starch Composites in Warm and Humid Environments.

For the application of poly(lactic acid) (PLA) and PLA/starch composites in technical components such as toys, it is essential to know their degradation behavior under relevant application conditions in a hydrothermal environment. For this purpose, composites made from PLA and native potato starch were produced using twin-screw extruders and then processed into test specimens, which were then subjected to various one-week ageing processes with varying temperatures (23, 50, 70, 90 °C) and humidity levels (10, 50, 75, 90%). This was followed by mechanical characterization (tensile test) and identification of degradation using Gel Permeation Chromatography (GPC), Thermogravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), and Nuclear Magnetic Resonance spectroscopy (NMR). With increasing temperature and humidity, there was a clear degradation of the PLA, which could be reduced or slowed down by adding 50 wt.% starch, due to increased crystallinity. Hydrolysis was identified as the main degradation mechanism for PLA and PLA/starch composites, especially above the glass transition temperature, with thermo-oxidative degradation also playing a subordinate role. Both hydrolytic degradation and thermo-oxidative degradation led to a reduction in mechanical properties such as tensile strength.

Analysis of Maillard reaction precursors and secondary metabolites in Chilean potatoes and neoformed contaminants during frying

Southern Chile native potatoes are an interesting raw material to produce novel snacks like colored potato chips. These novel products should be comprehensively evaluated for the presence of undesirable compounds such as acrylamide, 5-hydroxymethylfurfural and furan, the main neoformed contaminants in starchy rich fried foods. This study evaluated the neoformed contaminant levels and oil content on chips made from eleven Chilean potato accessions and compared them with commercial samples. The neoformed contaminant contents were related to Maillard reaction precursor levels (reducing sugars and asparagine) and secondary metabolites (phenolic compounds and carotenoids). Neoformed contaminants correlated well among them and were weakly correlated with reducing sugars and asparagine. Acrylamide level in native potato chips ranged from 738.2 to 1998.6 μg kg−1 while from 592.6 to 2390.5 μg kg−1 in commercial samples. Thus, there is need to implement neoformed contaminant mitigation strategies at different steps of the production chain of colored potato chips.

Hiding in Plain Sight: A Widespread Native Perennial Harbors Diverse Haplotypes of 'Candidatus Liberibacter solanacearum' and Its Potato Psyllid Vector.

The unculturable bacterium 'Candidatus Liberibacter solanacearum' (CLso) is responsible for a growing number of emerging crop diseases. However, we know little about the diversity and ecology of CLso and its psyllid vectors outside of agricultural systems, which limits our ability to manage crop disease and understand the impacts this pathogen may have on wild plants in natural ecosystems. In North America, CLso is transmitted to crops by the native potato psyllid (Bactericera cockerelli). However, the geographic and host plant range of the potato psyllid and CLso beyond the borders of agriculture are not well understood. A recent study of historic herbarium specimens revealed that a unique haplotype of CLso was present infecting populations of the native perennial Solanum umbelliferum in California decades before CLso was first detected in crops. We hypothesized that this haplotype and other potentially novel CLso variants are still present in S. umbelliferum populations. To test this, we surveyed populations of S. umbelliferum in Southern California for CLso and potato psyllid vectors. We found multiple haplotypes of CLso and the potato psyllid associated with these populations, with none of these genetic variants having been previously reported in California crops. These results suggest that CLso and its psyllid vectors are much more widespread and diverse in North American natural plant communities than suggested by data collected solely from crops and weeds in agricultural fields. Further characterization of these apparently asymptomatic haplotypes will facilitate comparison with disease-causing variants and provide insights into the continued emergence and spread of CLso.

Characterization of Nano- and Microstructures of Native Potato Starch as Affected by Physical, Chemical, and Biological Treatments.

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 μm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

Effects of Mineral Elements and Annealing on the Physicochemical Properties of Native Potato Starch

Native potato starch is an excellent carrier of minerals due to its inherent ion exchange capacity. Mineral enrichment not only changes the nutritional value but also influences starch pasting and swelling properties. Hydrothermal treatments like annealing constitute a straightforward and green way to tune functional properties. Here, novel combinations of mineral enrichment and annealing were studied. Ion exchange was readily achieved by suspending starch in a salt solution at room temperature over 3 h and confirmed by ICP-OES. Annealing at 50 °C for 24 h using demineralized water or salt solutions strongly affected pasting, thermal, and swelling properties. The obtained XRD and DSC results support a more ordered structure with relative crystallinity increasing from initially 41.7% to 44.4% and gelatinization onset temperature increasing from 60.39 to 65.94 J/g. Solid-state NMR spectroscopy revealed no detectable changes after annealing. Total digestible starch content decreased after annealing from 8.89 to 7.86 g/100 g. During both ion exchange at room temperature and annealing, monovalent cations promoted swelling and peak viscosity, and divalent cations suppressed peak viscosity through ionic crosslinking. The presented combination allows fine-tuning of pasting behavior, potentially enabling requirements of respective food applications to be met while offering an alternative to chemically modified starches.

Effect of fluidized-bed agglomeration with sugar binders on physical, crystallinity, thermal, and pasting properties of native potato starch.

Fluidized-bed agglomeration of native potato starch (NPS) with sugar binders [maltodextrin (MD) and lactose] produced larger particles with a more porous and diverse shape. Moreover, the agglomerated potato starch (APS) exhibited improved flowability and solubility. All powders displayed a B-type X-ray diffraction pattern. Although lactose did not impact the crystallinity of APS, that of APS prepared with MD decreased as the MD concentration increased. NPS showed higher gelatinization temperatures than APS prepared with distilled water (the control). Moreover, as binder concentration increased, the gelatinization temperatures and enthalpy of APS increased and decreased, respectively, indicating a delay in gelatinization. Similar results were observed with the pasting properties, wherein APS with sugar binders exhibited lower pasting, breakdown, setback, and final viscosities compared to the control. These were likely a result of decreased amylose leaching from the granules during heating due to the presence of sugar.

Effects of incubation time of plasma activated water (PAW) combined with annealing for the modification of functional properties of potato starch

The present study investigates the application of annealing and plasma-activated water (PAW) for starch modification, as alternative methods compared to the chemical one. Native potato starch was subjected to PAW, annealing with distilled water (DW-ANN), and the combination of the two (PAW-ANN) at different incubation times (1, 4, 8, and 12 h). The changes in rheological, pasting, and thermal properties were evaluated. The results showed that all treatments promoted significant modifications of the investigated parameters. In particular, while the pasting properties of the potato starch remained unchanged after the PAW treatment, G’ (elastic) and G’’ (viscous) of the PAW-treated starch were significantly (p < 0.05) higher than those of the native. DW-ANN significantly increased all rheological parameters and reduced peak viscosity, breakdown, and setback and significantly (p < 0.05) incremented pasting temperature, holding strength, and final viscosities of the potato starch may be due to cross-linking reaction. The combination of treatment (PAW-ANN) showed a synergistic effect leading to strong gel formation up to 4 h, while further treatment reduced the possibility of depolymerization. In conclusion, the combined treatment is a promising new green method to modify the properties of starch and improve its stability within a short treatment time.

Plant Growth Adaptations of Chilean Native Potato Under Higher Soil and Air Temperature: A Field Comparative Study

Plant Growth Adaptations of Chilean Native Potato Under Higher Soil and Air Temperature: A Field Comparative Study

Influence of Infrared Dry Heat Treatment on the Structure and Properties of Potato Starch

AbstractThe current study presents a novel approach to starch modification using infrared dry heat treatment (IR‐DHT). IR‐heating at 200 °C allows one to reduce the processing time to 15 min and does not lead to irreversible amorphization of starch structure. Upon IR‐DHT, an increase in density of starch granules from 1.4888 ± 0.0005 to 1.5038 ± 0.0005 g cm−3 is observed. The crystallinity degree of the starch exposed in water at 20 °C after IR‐DHT does not change compared to the crystallinity of native starch hydrated at the same temperature. However, the exposure in excess of water of native potato starch at 45 °C induces an increase of crystallinity up to 81% (along with a significant increase in the intensity of the d100 reflection), while heat‐treated starch exposed in water at the same temperature has reduced crystallinity (RC = 39%). In addition, the concentration of soluble carbohydrates released during the exposure process (45 °C, excess of water) increases by an order of magnitude for heat‐treated starch compared to the native sample. Hence, IR‐DHT may become a promising way to influence the processes of acid and enzymatic hydrolysis and control starch properties, such as pasting, solubility, and digestibility.

An international breeding project using a wild potato relative Solanum commersonii resulted in two new frost-tolerant native potato cultivars for the Andes and the Altiplano.

This breeding project, initiated at the United States Potato Genebank (USPG) in collaboration with Peruvian partners Instituto Nacional de Innovacion Agraria (INIA), International Potato Center, Peru (CIP), and local farmers, sought to enhance cold hardiness and frost tolerance in native potato cultivars in Peru. The Andes and Altiplano are often affected by frost, which causes significant reduction in yield; creating varieties with superior resilience is a critical undertaking. The goal was to transfer outstanding non-acclimated cold tolerance and acclimation capacity found in wild potato species Solanum commersonii (cmm). Breeding families segregating for cold hardiness were created using (a) a somatic hybrid cmm + haploid Solanum tuberosum (tbr) (cv. Superior, US variety from Wisconsin) as male and (b) seven cultivars native to Peru of the species S. tuberosum sbsp. andigenum (adg) as females. All plant materials were part of the USPG germplasm collection. Sexual seeds of each family were sent to Peru for evaluations under the natural conditions of the Andean highlands and Altiplano. The plants were assessed for their response to frost, and genotypes showing exceptional tolerance were selected. Plants were also evaluated for good tuber traits and yield. Initial planting involving ~2,500 seedlings in five locations resulted in selecting 58 genotypes with exceptional frost tolerance, good recovery capacity after frost, and good tuber traits. Over the years, evaluations continued and were expanded to replicated field trials in the harsher conditions of the Altiplano (Puno). All trials confirmed consistency of frost tolerance over time and location, tuber quality, and yield. After 8 years, two advanced clones were considered for cultivar release because of their exceptional frost tolerance and superior field productivity that outyielded many of the established cultivars in the region. In November 2018, a new native cultivar named Wiñay, a Quechua word meaning "to grow" was released in Peru. In 2022, a second cultivar followed with the name Llapanchispaq (meaning "for all of us"). This project evidenced that a multinational and all-encompassing approach to deploy valuable genetic diversity can work and deliver effective results. This is even more significant when outcomes can promote food security and sustainability in very vulnerable regions of the world.

Rheological and tribological properties of native potato starch agglomerated by fluidized bed granulator

We explored the rheological and tribological properties of potato starch agglomerated with a sugar binder (maltodextrin or lactose) at various concentrations by using a fluidized bed granulator. The magnitudes of consistency index and apparent viscosity of agglomerated potato starch (APS) decreased as the binder concentration was increased. Moreover, APS with a sugar binder showed lower viscoelastic moduli and higher tan δ values compared to APS with water as the binder (the control). The gel strength of all agglomerates decreased as the sugar concentration was increased. All samples showed anti-thixotropic behavior, and especially, APS with 20 % lactose showed a small anti-thixotropic area. Utilizing the Arrhenius equation clearly elucidated the effect of temperature on the apparent viscosity of all the samples. Although the maltodextrin concentration had little influence on the activation energy of APS, it increased as the lactose concentration was increased. APS samples with a sugar binder showed greater friction coefficient values compared to the control, with maltodextrin having a significant impact. The findings indicate that the rheological and tribological properties of APS rely on the type and concentration of sugar binder.

Correlation between the activation energy of PLA respectively PLA/starch composites and mechanical properties with regard to differ accelerated aging conditions.

Within this research semi-crystalline polylactide and composites with 50 wt.% native potato starch were compounded and injection molded. The material was mechanically characterized by tensile, three-point bending, and Charpy impact tests. These tests were carried out in the freshly molded state and after 332 and 792 h of storage at accelerated temperature or humidity. The respective activation energy was calculated by applying the Flynn-Wall-Ozawa method. The focus of the study was to investigate the correlation between the activation energy and the related mechanical and thermal properties. The results showed that the addition of native potato starch as a filler prevents the decrease in activation energy over the course of the experiments. Thus, the PLA/starch composite is more resistant to the two aging conditions than the pure PLA. When considering the mechanical properties, the pure PLA showed a large deviation of results compared to the initial value in a range of +63.88% to -33.96% with regard to the respective aging conditions, whereas the PLA/starch composite properties nearly always remained at the initial values. Through the investigation of the mechanical and thermal properties, it was shown that the steady activation energies are consistent with the mechanical properties, as these have shown only a small deviation of the mechanical properties during the duration of experiments for the PLA/starch composite.

Improving the Three-Dimensional Printability of Potato Starch Loaded onto Food Ink.

This study focuses on improving the 3D printability of pea protein with the help of food inks designed for jet-type 3D printers. Initially, the food ink base was formulated using nanocellulose-alginate with a gradient of native potato starch and its 3D printability was evaluated. The 3D-printed structures using only candidates for the food ink base formulated with or without potato starch exhibited dimensional accuracy exceeding 95% on both the X and Y axes. However, the accuracy of stacking on the Z-axis was significantly affected by the ink composition. Food ink with 1% potato starch closely matched the CAD design, with an accuracy of approximately 99% on the Z-axis. Potato starch enhanced the stacking of 3D-printed structures by improving the electrostatic repulsion, viscoelasticity, and thixotropic behavior of the food ink base. The 3D printability of pea protein was evaluated using the selected food ink base, showing a 46% improvement in dimensional accuracy on the Z-axis compared to the control group printed with a food ink base lacking potato starch. These findings suggest that starch can serve as an additive support for high-resolution 3D jet-type printing of food ink material.