Starch recovery from turmeric wastes using supercritical technology

Characterization of a Novel Starch Isolated from the Rhizome of Colombian Turmeric (Curcuma longa L.) Cultivars

Turmeric (Curcuma longa L.) plants are native to Southeast Asia and are part of the Zingiberaceae family. Global consumption and production of this plant are expanding. In countries such as Colombia, turmeric is a promising cultivar. Curcuminoids derived from its rhizomes are used in food, pharmaceuticals, and natural cosmetics. Curcuminoids constitute approximately 3 wt% of the rhizome. Many residues rich in cellulose and starch can thus be recovered. This study characterizes a novel starch isolated from Colombian turmeric cultivars. The morphological parameters of the starch were determined using microscopic techniques such as scanning electron microscopy (SEM). Proximate analysis and infrared spectroscopy (ATR-FTIR) were used to analyze the chemical composition, while physical analyses included thermal characterization, swelling power testing, solubility, water retention capacity, and colorimetry evaluation. The new starch granules were ellipsoidal in shape and ranged in diameter from 19.91 to 38.09. A trace amount of remaining curcumin was identified through chemical and physical characterization. The swelling power was 3.52 ± 0.30, and its water retention capacity was 3.44 ± 0.30. Based on these findings, turmeric can be useful in both food and non-food applications. Because starch was extracted from other Zingiberaceae plants, this study also includes a brief review of the related literature.

Starch/PVOH aqueous solutions: a chemical-physical characterization

This work investigates the relationship between the structure and physicochemical properties of three different starches in starch/polyvinyl alcohol aqueous solutions. For this purpose, accurate nuclear magnetic resonance (NMR) analyses were performed to determine the role that the starch structure plays in the formation of binder solutions. Moreover, a dynamic shear rheometer (DSR) was used to investigate the mechanical properties of the solutions and correlate them with the structure of each starch. Complete characterization of the analysed starches and the starch/PVOH solutions was also carried out through light scattering measurements. Furthermore, by crossing the data coming from NMR and light scattering with those coming from rheology, the best solution was identified. Finally, to confirm the interaction mechanism between starch and PVOH, thermogravimetric analysis and an NMR study, using 1H and 13C NMR spectra, were carried out on the film obtained from the best solution. The analyses carried out showed that PVOH has a stabilizing effect on starch/PVOH solutions, and the starch with the greatest branching degree is the one that forms a more structured network.

Essential characteristics improvement of metallic nanoparticles loaded carbohydrate polymeric films - A review

Petroleum-based films have contributed immensely to various environmental issues. Developing green-based films from carbohydrate polymers is crucial for addressing the harms encountered. However, some limitations exist on their property, processibility, and applicability that prohibit their processing for further developments. This review discusses the potential carbohydrate polymers and their sources, film preparation methods, such as solvent-casting, tape-casting, extrusion, and thermo-mechanical compressions for green-based films using various biological polymers with their merits and demerits. Research outcomes revealed that the essential characteristics improvement achieved by incorporating different metallic nanoparticles has significantly reformed the properties of biofilms, including crystallization, mechanical stability, thermal stability, barrier function, and antimicrobial activity. The property-enhanced bio-based films made with nanoparticles are potentially interested in replacing fossil-based films in various areas, including food-packaging applications. The review paves a new way for the commercial use of numerous carbohydrate polymers to help maintain a sustainable green environment.

Valorization of Cereal Byproducts with Supercritical Technology: The Case of Corn

Ethanol and starch are the main products generated after the processing of corn via dry grinding and wet milling, respectively. Milling generates byproducts including stover, condensed distillers’ solubles, gluten meal, and the dried distillers’ grains with solubles (DDGS), which are sources of valuable compounds for industry including lignin, oil, protein, carotenoids, and phenolic compounds. This manuscript reviews the current research scenario on the valorization of corn milling byproducts with supercritical technology, as well as the processing strategies and the challenges of reaching economic feasibility. The main products recently studied were biodiesel, biogas, microcapsules, and extracts of enriched nutrients. The pretreatment of solid byproducts for further hydrolysis to produce sugar oligomers and bioactive peptides is another recent strategy offered by supercritical technology to process corn milling byproducts. The patents invented to transform corn milling byproducts include oil fractionation, extraction of undesirable flavors, and synthesis of structured lipids and fermentable sugars. Process intensification via the integration of milling with equipment that operates with supercritical fluids was suggested to reduce processing costs and to generate novel products.

Aqueous Extraction of Curcuminoids from Curcuma longa: Effect of Cell Disintegration Pre-treatment and Extraction Condition

Cell structure modification techniques have the potential to improve curcuminoid recovery in Curcuma longa. In this study, different pre-treatments such as high hydrostatic pressure (HPP, high pressure processing), ultrasound (US), pulsed electric field (PEF), and ohmic heating (OH) were used on dried C. longa before aqueous extraction at pH 2.0, 5.0, and 8.0. The released curcuminoids, cell disintegration index (Zp), particle size distribution (PSD), and color (CIE L*, a*, b*) were used to evaluate the different pre-treatment impacts on plant structure and extract properties. In untreated turmeric, the highest amount of released curcuminoids (3.89 mg/g dry matter) was obtained after extraction for 30 min at 95° in the aqueous phase. After pre-treatments, the acidic conditions showed a considerable improvement in curcuminoid recovery; PEF, HPP, and OH improved the curcuminoid recovery by 3.39-, 3.13-, and 1.24-fold, respectively; while US did not lead to an increased release of curcuminoids compared to the untreated material. The highest curcuminoid recovery (with PEF and extraction at pH 5.0) was 6.6% w/w of the total curcuminoids. The non-thermal pre-treatments have less impact on the extract’s color compared to the extraction pH, with alkaline conditions reducing the lightness of the extract.

Extraction of curcumin from turmeric residue (Curcuma longa L.) using deep eutectic solvents and surfactant solvents

Using waste materials to extract biologically active ingredients with green solvents is a new trend for sustainable development. Herein, different types of deep eutectic solvents (DESs) and surfactant solvents (SSs) were used to extract curcumin from turmeric residues (TRs), among which choline chloride-propylene glycol (ChCl-Pro) showed the highest yield. The optimized extraction conditions included a ChCl : Pro ratio of 1 : 2, water content in the DESs of 20%, solid : liquid ratio of 1 : 40 maintained for 60 min at 50 °C, and a TR particle size of 0.18 mm. The extraction yield was 54.2 mg g^-1, which was 1.31 times higher than when methanol was used as a solvent. Distilled water was used to recover curcumin from the DES extract with a recovery yield of 99.7%. Furthermore, the antioxidant and acetylcholinesterase (AChE) inhibitory activities of the recovered curcumin were evaluated, with IC₅₀ values of 25.58 ± 0.51 and 19.12 ± 0.83 μg mL^-1, respectively. This study highlights the promising potential of using green solvents to extract bioactive compounds from waste materials.

Production and evaluation of novel functional extruded corn snacks fortified with ginger, bay leaves and turmeric powder

Abstract

Extruded corn snacks are accepted by all human ages especially children, but they have low functional value. Therefore, corn extruded snacks contain rich nutraceuticals dried herbs including Laurus nobilis (T1), Curcuma longa (T2), Zingiber officinale Roscoe (T3), and the mixture of these herbs (T4) were manufactured and analyzed. The results declared that all the herbal extruded corn snacks had significantly higher ash, fibers, minerals, and vitamins A and B6. For minerals, the highest percent of increase compared to control was achieved by Fe, K, Ca, Zn content in order, being the highest in T4. The contents of Vitamin A and B6 were ranged from 283 to 445 IU/100 g and from 0.01 to 0.08 mg/100 g for the herbal extrudates, respectively. The increased percent in herbal corn snacks relative to control ranged from 743 to 452%, 188 to 17.6%, and from 313 to 99% for total phenolics, flavonoids, and antioxidant activity. Besides, the highest number of phenolic compounds was recorded in T4. Despite the fact that approximately all herbal extruded products had good texture and color characteristics, the best formulation was T2 and T4 corn snacks. Furthermore, the extruded products were microbiologically safe for up to 9 months. The formulation of herbal-corn snacks could fulfill consumers’ requirement for ready-to-eat-healthy foods with acceptable sensory attributes and also economically suitable for the food industry.

Graphical abstract

Natural Starch in Biomedical and Food Industry: Perception and Overview

Utilization of native starch is increasing globally because of its wide distribution and natural occurrence. Starch is mainly abundant in tubers and food grains. Scientific research on starch is increasing in recent years due to its unique physiochemical and biomedical properties. Native starch is an emerging biopolymer and copolymer in the biomedical and pharmaceutical areas due to its renewability, biocompatibility, biodegradability, and relative inexpensiveness. Today, there is an increasing interest in natural starches to design and produce diverse products due to their pertinent structural properties and non-toxicity. Due to these attributes, these natural polymers are becoming functional core materials in the biomedical industry, construction materials, medicine industry, food industry, food packaging, and carrier for active drugs. In this paper, we mainly attempt to analyze the physicochemical attributions and the biomedical applications on native or non-conventional starches obtained from the natural botanical sources.

Recent advances on the sustainable approaches for conversion and reutilization of food wastes to valuable bioproducts

The increasing amounts of food wastage and accumulation generated per annum due to the growing human population worldwide often associated with environmental pollution issues and scarcity of natural resources. In view of this, science community has worked towards in finding sustainable approaches to replace the common practices for food waste management. The agricultural and food processing wastes rich in nutrients are often the attractive substrates for the bioconversion for valuable bioproducts such as industrial enzymes, biofuel and bioactive compounds. The sustainable approaches on the re-utilization of food wastes as the industrial substrates for production of valuable bioproducts has meet the goals of circular bioeconomy, results in the diversify applications and increasing market demands for the bioproducts. This review discusses the current practice and recent advances on reutilization of food waste for bioconversion of valuable bioproducts from agricultural and food processing wastes.

Physicochemical properties of starch obtained from Curcuma karnatakensis - A new botanical source for high amylose content

Curcuma karnatakensis, a member of Zingiberaceae, is endemic to the state of Karnataka, India. The structure and physicochemical properties of starch isolated from rhizomatous rootstocks of two samples - A and B were analyzed for the first time. Sample A contains 76.4 ± 0.3% of starch, of which 86.6 ± 0.4% is amylose, while sample B has 75.0 ± 0.4% of starch containing 84.6 ± 0.4% of amylose according to UV-Vis spectrophotometric analysis. The shape of the starch granules in both the samples is polygonal and cuboidal with a smooth surface, as revealed by SEM studies. The X-ray diffractogram indicated A type of polymorphs in contrast to other Curcuma species, where B types are reported. Since its high amylose content leads to an increased tendency to retrogradation and the formation of resistant starch, this taxon could become one of the major dietary sources of starch in the future. In addition, a source rich in amylose specifies its prospective application in the pharmaceutical and biodegradable film industry.