Search Results (83)

Despite the well-documented effects of polyphenols on the nutritional properties of starch, information regarding the structure of starch–polyphenol complexes remains limited. Therefore, this study aimed to investigate the molecular, chemical, and microstructural properties of starch-polyphenol complexes prepared from wheat, rice, potato, and maize starches. Apparent amylose content was determined spectrophotometrically, molecular interactions were analyzed using Fourier Transform Infrared (FTIR) spectroscopy, and morphological changes were evaluated by scanning electron microscopy (SEM). Significant differences in apparent amylose content were observed following the incorporation of selected polyphenols, especially epigallocatechin gallate. FTIR analysis suggested that polyphenols may alter the molecular organization of starch matrices through non-covalent interactions, predominantly hydrogen bonding. Epigallocatechin gallate and quercetin exerted more noticeable effects than the other polyphenols studied. Furthermore, SEM observations performed exclusively on starch systems containing epigallocatechin gallate revealed noticeable morphological alterations in native starch granules following in vitro digestion compared with undigested controls. These findings provide new insights into the formation of starch-polyphenol complexes and support their potential application in the development of functional foods with improved nutritional properties. Full article

Ulluco (Ullucus tuberosus), the second most economically important Andean tuber after potato, has been cultivated for over 5500 years. Despite its resistance to frost, drought, and high altitudes, as well as its biochemically complex profile, ulluco remains underrepresented in the scientific literature and absent from international markets. This comparative review synthesises the evidence available up to November 2025 regarding its biology, nutritional profile, phytochemistry, and food industry applications relative to four other Andean tubers: oca (Oxalis tuberosa), mashua (Tropaeolum tuberosum), native potato (Solanum tuberosum L.), and yacon (Smallanthus sonchifolius). The main comparative findings are as follows: First, ulluco is the only Andean tuber that biosynthesises betalains instead of anthocyanins, producing up to 32 distinct compounds that are stable across a pH range of 3–7, a chromatic stability advantage over anthocyanin-based pigments from mashua, oca, and native potato, which suggests its potential as a source for the development of clean-label natural colourants. Second, among the five species evaluated, ulluco protein content across different morphotypes ranges from 5.60 to 15.7 g/100 g dry weight, ranking within the upper range of values reported for mashua and oca, and comparable to or higher than the upper ranges reported for native potato and yacon. This variability reflects the genotypic and ecogeographical diversity of the evaluated accessions and is not a methodological inconsistency, with 20% of varieties exceeding 10 g/100 g and providing six essential amino acids, supporting genetic improvement programmes aimed at nutritional security. Third, ulluco starch exhibits a low gelatinisation temperature (56–60 °C), a high amylose content (24–36%), and pseudoplastic behaviour, properties comparable or superior to potato starch for specific applications, with technical viability validated at a laboratory scale in applications including biodegradable films, food 3D printing inks, and dehydrated snacks. Unlike yacon, which accumulates fructooligosaccharides and lacks starch, ulluco aligns with oca, mashua, and potato as a starch-accumulating species. Critical gaps identified include the absence of clinical evidence on betalain bioavailability, the lack of a complete nuclear genome assembly, and the non-existence of standardised processing methods for industrial scaling. A coordinated agenda that integrates clean seed programmes, pilot-scale validation, and genomic breeding is essential for the bioeconomy of the 21st century to transform ulluco into a high-value ingredient. Full article

Industrial potato processing generates substantial rejected-tuber streams that are rarely valorized. This study optimized wet-process starch extraction from rejected Solanum tuberosum L. (Pastusa variety) sourced from a Colombian snack processor (Comestibles Ricos S.A., Super Ricas, Bogotá), using a Box–Behnken design with three factors: temperature (20–40 °C), solid-to-liquid ratio (1:2–1:4, w/v), and citric acid concentration (0–6%, w/v; n = 26 per material). The reduced model (F = 9.236, p = 0.0003) identified temperature (β₁ = +0.729) and solid-to-liquid ratio (β₂ = +0.695) as the dominant yield drivers, with the identified optimum located at the boundary of the tested domain, indicating that an expanded range may yield further gains. Across the full experimental domain, rejected-grade potato produced significantly higher starch yields than standard-grade material (3.06 ± 1.20% vs. 1.85 ± 0.53%; Welch’s t = 4.70, p < 0.0001, Cohen’s d = 1.30). Under the identified optimal conditions (40 °C, 1:4 w/v, 3% citric acid), rejected-grade tubers yielded 5.41 ± 1.30%, 3.6-fold higher than standard-grade material processed under the same conditions (1.49 ± 0.14%), consistent with pre-existing intracellular starch release from mechanically damaged tubers. Total starch content reached 83.4 ± 2.6% (dry basis) as determined by the Megazyme K-TSTA-100A enzymatic kit (AOAC 996.11), with CV < 1.5% between independent extractions. UV-Vis spectrophotometry of the iodine–starch complex (600 nm; R² = 0.9830) confirmed native amylose-rich starch identity. These results establish rejected Pastusa potato as a statistically robust circular-economy feedstock for native starch recovery. Full article

Potato starch (Solanum spp.) undergoes structural and functional modifications during traditional Andean chuño production; however, the integrated effects of processing history, cultivar-associated characteristics, and field-based environmental conditions remain insufficiently characterised. This study investigated the effects of chuño processing on the compositional, pasting, morphological, molecular, and crystalline properties of starches isolated from three potato cultivars (Condor Imilla, Luk’i Turno, and Dutch Désirée). Native and chuño starches were characterised by amylose quantification, viscoamylography, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD), together with severe thermal treatment to evaluate structural stability. Chuño processing was associated with a reduction in amylose content across all cultivars (6.9–23.4%) and an increase in gelatinisation onset temperature of approximately 21.5% (from ~65 °C to ~79 °C). Peak viscosity decreased substantially after processing (457.5–1110 BU to 194.5–442.5 BU), while breakdown values remained close to zero, indicating increased resistance to viscosity loss during heating. SEM analysis revealed changes in granule morphology and size distribution associated with chuño processing and subsequent thermal treatment, with more pronounced reductions in granule size observed in Condor Imilla and Luk’i Turno than in Dutch Désirée. FT-IR analysis demonstrated modifications in short-range molecular organisation without the appearance of new functional groups, indicating structural reorganisation rather than chemical transformation. XRD analysis confirmed that all starches retained the native B-type crystalline polymorph after chuño processing, although reductions in diffraction intensity and peak definition indicated decreased long-range structural order. Severe thermal treatment eliminated detectable crystalline order in all samples, producing predominantly amorphous diffraction profiles. Overall, chuño processing was associated with reduced swelling capacity, lower paste viscosity, enhanced thermal stability, and multiscale structural reorganisation while preserving the fundamental B-type polymorph. Given that the plant material originated from distinct agroecological environments and that traditional chuño production involved a variable number of processing cycles, the observed differences should be interpreted as integrated responses of starch systems to processing history and material characteristics rather than strictly genotype-driven effects. These findings highlight the potential of chuño as a naturally modified starch system with distinctive technological properties. Full article

Native Andean potatoes (Solanum tuberosum subsp. andigenum) are a valuable phytogenetic resource due to their compositional diversity and adaptation to high-altitude environments. Their starch is a key functional polysaccharide widely used in food systems; however, information on the kinematic viscosity of dilute gels under moderate thermal conditions remains limited. This study evaluated the effects of temperature (26, 36, and 46 °C) and starch concentration (1–3% w/v) on the kinematic viscosity of gels from three Andean potato varieties: Imilla Negra, Compis, and Peruanita. Starch was extracted from fresh tubers (Puno, Peru) using a wet extraction method, and gels were prepared by heating dispersions at 85 °C for 5 min under controlled conditions. Viscosity (0.61–34.47 cSt) decreased with increasing temperature and increased with concentration, confirming the sensitivity of these systems to thermal and compositional factors. The Arrhenius model adequately described temperature dependence, with activation energies of 15.19–29.75 kJ·mol⁻¹, showing an increasing trend with concentration. At 3% and 26 °C, viscosity followed Compis > Imilla Negra > Peruanita, indicating varietal differences in thickening capacity. These results provide useful rheological data for the design and optimisation of food processes involving dilute Andean potato starch dispersions. Full article

This study systematically evaluated the potential of five native starches, including corn (CS), potato (PS), tapioca (TS), rice (RS), and sweet potato (SPS), as fat replacers in low-fat pork sausages. The obtained results showed that amylose content varied significantly, with PS and SPS having the highest levels (30.06% and 28.60%, respectively), which were beneficial for forming starch gels. Correspondingly, PS and SPS demonstrated the highest solubility and swelling power. In sausage applications, PS and SPS exhibited superior water-retention capacities, with drying losses of 6.75% and 7.03%, and cooking losses of 2.23% and 2.52%, which were lower than those of the normal control (NC) and low-fat control (LFC) groups. Moreover, the results of texture profile analysis revealed that PS and SPS enabled the sausages to achieve the highest levels of hardness and springiness, contributing to maintaining the moisture retention and toughness of the sausages. Electronic tongue and nose analyses indicated that incorporating these starches did not adversely affect the taste and odor profiles of the sausages, except for RS, which showed distinct flavor encapsulation properties. Overall, PS and SPS served as excellent fat replacers in the meat industry, offering healthier alternatives without compromising product quality. Full article

In the present study, potato starch (PS) was functionalized with theaflavin (TF). Potato starch aldehyde (DPS)–theaflavin (DPS-TF) conjugates were prepared by conjugating TF with DPS. The synthesized DPS-TF conjugates were characterized via UV–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), proton nuclear magnetic resonance (¹H-NMR) and scanning electron microscopy (SEM) analysis and tested for antioxidant and antimicrobial activities. The UV–vis spectrum results demonstrated that DPS-TF conjugates exhibited the characteristic absorption peaks of theaflavin at 280 nm, which can be attributed to the benzotropolone structure present in theaflavin. The absorbance values of the peaks progressively intensified as the concentration of grafted theaflavins increased. FTIR confirmed the depletion of the aldehyde groups and the presence of TF-specific vibrations in the conjugates in DPS-TF. ¹H-NMR demonstrated that the conjugation occurred between the H-6, H-8, H-6′, and H-8′ positions of theaflavin and the aldehyde groups of starch aldehyde. XRD demonstrated that the DPS-TF conjugates were in the amorphous state. SEM observation demonstrated that DPS-TF exhibited a mixed morphology of flakes and lumps, which differed from that of native starch and starch aldehyde. The scavenging activity of DPS-TF against DPPH and ABTS radicals was significantly higher than that of DPS (p < 0.05), with the antioxidant activity increasing in line with the concentration of theaflavins. In comparison with PS and DPS, DPS-TF conjugates demonstrated superior antimicrobial activity against Escherichia coli and Staphylococcus aureus. Furthermore, an elevated grafting ratio corresponds to a heightened level of these functional properties. This study highlights the promise of the starch aldehyde–theaflavin conjugates for use as a viable antioxidant and antimicrobial agent for food applications. Full article

Starch systems and their extrudates can be used as edible films, carriers, and encapsulants for bioactive substances in various industries, primarily the food, medicine, and pharmacy industries. Using appropriate modification methods, it is possible to alter their physicochemical properties to improve specific functional parameters, thereby enhancing their application potential. The aim of this study was to characterize potato starch extrudates enriched with two types of edible oils (rapeseed or sunflower) at concentrations of 3%, 6%, and 9%. Chemical modification was carried out using K₂CO₃ as a catalyst. The structure of native and modified starch extrudates was examined using optical/confocal microscopy, FTIR, and LTNA (low-temperature nitrogen adsorption). Analogous starch dispersions were studied using static and dynamic light scattering, SLS/DLS, nephelometric methods, and electrophoretic mobility measurements to determine surface charge levels and stability. Additionally, viscosity curves were determined as a function of time and temperature. It was found that starch extrudates with 6% sunflower oil content showed optimal functional properties, characterized by greater stability, higher structural order, and better oil complexation. These findings directly translate into significant potential applications, including the development of functional products in the food industry. Full article

Potato starch offers the unique potential of mineral enrichment through the presence of phosphorylated amylopectin chains. This property was utilised in a straightforward dual modification of native potato starch by combining mineral enrichment with dry heat treatments (DHT). DHT itself (110–130 °C, 3–6% moisture, 2 h) affords potato starches with lower viscosity and gelatinisation temperatures and higher contents of digestible starch. Prior ion exchange with Na⁺, K⁺, Mg²⁺, and Ca²⁺ enhanced the versatility of dry heat treatments. This study demonstrates the fine-tuning of functional properties (rheology) of these novel, dual-modified starches. Of special interest are magnesium and calcium due to their nutritional value and their valency, allowing ionic cross-linking. The present study contributes to the understanding of starch–ion interactions in DHT, clearly highlighting the role of specific ion effects, as per the Hofmeister series (K⁺ > Na⁺ and Ca²⁺ > Mg²⁺), in addition to the reversible ionic cross-linking effect of divalent cations. This knowledge is of use for potential substitution of chemically modified starches in food products, serving relevant trends and needs of today’s food industry for clean-label starches. Full article

Pea starch, often obtained as a by-product of pea protein isolation, is increasingly available and economically attractive. Consequently, the industry is seeking new applications of pea starch, both in its native and modified forms. This paper highlights the topic of pea and potato starch oxidation with ozone in aqueous suspension and evaluates the effect of process time, retention volume and solids content on pasting, texture, and flow behavior, benchmarking against a commercial hypochlorite-oxidized product. Moreover, obtained preparations were studied for their molecular mass distribution and hydrodynamic parameters. It was found that the oxidation of both potato and pea starch with ozone in an aqueous suspension is an effective method of obtaining this type of starch preparations. The extent of modification was dependent on all variables considered in the research. The depolymerization of both starch varieties progressed gradually, but the oxidation effects were more noticeable for potato starch compared to pea starch, which was found to be related to the gelling characteristic of those preparations. Full article

Intelligent films (IFs) incorporating natural colorants and biodegradable materials offer innovative solutions for monitoring food freshness and spoilage. This study evaluated the impact of varying the PVA-APN ratio on films formulated with Peruvian Purple Potato starch (APN) and anthocyanin extract (AE). The research focused on the effects of PVA on physicochemical and mechanical characteristics, as well as the color changes observed when the films were used with seafood. The results indicated a decrease in chroma a* and an increase in chroma b* when the films were in contact with different buffer solutions (from acidic to alkaline). Solubility decreased with higher starch concentrations and the mechanical properties revealed a reduced tensile strength and elongation with increased APN concentration. The films effectively indicated freshness, with the best ΔE values for the 50:50 formulations (13.6 ± 1.6 and 12.04 ± 2.8 for fish and shrimp, respectively), making them promising candidates for intelligent seafood packaging. Full article

The growing need for sustainable packaging materials with enhanced functionality has prompted our investigation into biodegradable polymers reinforced with nanostructures. In this work, we began by extracting anthocyanins from pigmented native potatoes (Solanum tuberosum) and confirming their concentration via UV–Visible spectroscopy. The corresponding potato starch was then characterized according to its amylose and amylopectin contents. The natural pigments subsequently served as reducing and stabilizing agents in a green synthesis of silver nanoparticles (AgNPs), which were subsequently incorporated into starch matrices derived from the same tuber. To evaluate the performance of the resulting composite films, we examined their pH-responsive color behavior—demonstrating their potential as visual indicators—their molecular structure through FTIR analysis—to verify the successful integration of AgNPs—and their moisture content as a measure of barrier properties. The AgNP-containing films exhibited markedly improved color stability across varying pH levels and superior moisture retention compared to pure starch films. These results illustrate the promise of combining underutilized Andean crops with eco-friendly nanotechnology to produce advanced, biodegradable materials suitable for intelligent food-packaging applications. Full article

The utilization of modified starches derived from ginger, sweet potatoes, and maize has been employed as a strategy to reduce the oil content in mayonnaise formulations. Amylose–lipid complexes and the native starches were synthesized, characterized, and subsequently incorporated into various mayonnaise formulations, replacing 50 and 80 percent of the oil. The sensory analysis showed that the mayonnaises produced with 50% and 80% modified corn starch were particularly well received. However, when compared to conventional mayonnaises, the viscosity of the mayonnaises prepared with 50% and 80% modified maize starch was found to be remarkably low. This outcome demonstrates that when preparing low-fat mayonnaise, it is not possible to substitute tuber starches for fat. Full article

The spray-dried potato starch was produced by gelatinizing native potato starch at two concentrations of 3% and 5% at 75 °C for 30 min, followed by drying in a pilot-scale spray dryer. X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and optical microscopy were applied to characterize native potato starch and spray-dried (SD) potato starch powders. The physical properties of the starches, including moisture content, color, bulk density, tapped density, particle size parameters, water holding capacity, and hygroscopicity, were investigated. XRD, DSC, and FTIR revealed the formation of a semi-crystalline to amorphous structure in the spray-dried starch powders. Microscopic examination showed that the starch granules of native potato starch were spherical and regular in shape, while spray-dried (SD) starch powders displayed wrinkled granules. The moisture content of the spray-dried powders was significantly lower than that of the native starch, while the native starch had higher particle size values [D(4.3)] compared to the spray-dried powders. Higher water holding capacity values were also recorded in the spray-dried starches compared to the native starch. Regarding the color parameters, statistical analysis revealed similar values for lightness (L*) and yellowness (YI) indices, while significant differences were found in hue angle (H°), a*, and b* values. A principal component analysis (PCA) was carried out to investigate the relationships among the physical properties of the native potato starch and spray-dried starch powders. The findings of the present study highlight the potential application of physically modifying starch through the spray-drying process. Full article

(1) Background: The aim of the work was to investigate the influence of selected physico-chemical factors on the solubility and release rate of CT (cryptotanshinone) in alcohologels. (2) Methods: The alcohologels of methylcellulose (MC), hydroksyethylcellulose (HEC), polyacrylic acid (PA) and polyacrylic acid crosspolymer (PACP) with CT were prepared and/or doped with native potato starch (SN) and modified citrate starches (SM2.5 and SM10). The analytical methods included evaluation of CT release profiles, Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and electrospray ionization mass spectrometry (ESI-MS), and scanning electron microscope (SEM) images were performed. (3) Results: The release and decomposition kinetics of CT in relation to the phosphate buffer solution (PBS) and methanol were observed. The amount of cryptotanshinone (CT) released into PBS was significantly lower (2.5%) compared to its release into methanol, where 22.5% of the CT was released into the model medium. The addition of SM2.5 to the alcohologel significantly increased the CT content to 70% in the alcohologel preparation containing NaOH (40%), and this enhanced stability was maintained for up to two months. The ATR-FTIR exhibited interactions between PA and 2-amino-2-methyl-1,3-propanediol (AMPD) as well as between PA and NaOH in case of the alcohologels. Moreover, it indicated the interaction between CT and NaOH. PXRD diffractograms confirmed the FTIR study. (4) Conclusions: The study observed the influence of a number of factors on the solubility and release rate of CT, as: alkalizers and their concentration, SM2.5 addition. The transition of CT in the presence of NaOH to the tanshinone V sodium (T-V sodium) form was suspected. Full article