High methoxyl pectin enhances the expansion characteristics of the cornstarch relative to the low methoxyl pectin

The Effect of Polysaccharide Colloids on the Thermal Stability of Water-in-Oil Emulsions

The preference and demand for low-fat diets have increased due to their health benefits. This study aimed to develop a thermally stable water-in-oil (W/O) emulsion. The addition of 3.75 wt% of polysaccharide colloids, including curdlan gum (CG), kappa-carrageenan (kC), gellan gum (GEG), guar gum (GUG), high-ester pectin (HEP), and carboxymethyl cellulose (CMC), to the aqueous phase resulted in the formation of a gel structure within it. Furthermore, these polysaccharide colloids reduced the excessive mobility of water droplets under high-temperature conditions. The oil phase consisted of anhydrous butter and a lipophilic nonionic surfactant. The emulsion was subjected to a heat treatment at 95 °C for 30 min, and the emulsions before and after the heat treatment were characterized. The results showed that among the above colloidal emulsions, the 3.75 wt% CG emulsion did not show significant changes in viscosity, stability index, mean particle size, friction coefficient, and encapsulation efficiency before and after heat treatment. The 3.75 wt% CG colloid showed the most significant enhancement in the thermal stability of W/O emulsions. This study proposes a novel fat-replacement strategy for products requiring high-temperature processing, such as processed cheese.

Impact of citrus pectin on the foaming behavior, structures, and barrier properties of the starch foam blocks

The starch foam displays weak barrier properties under humid storage, which limits its applications in the food industry. In this study, citrus pectin was loaded to strengthen the starch foam. Results showed that the pectin (4 wt% ∼ 8 wt%) effectively modified the cell structures of the starch foam block. This was attributed to the increased viscosity of the starch melt during foaming and the enhanced cell stability during cooling, which was promoted by the formation of entanglements, hydrogen bonds, and ester bonds between pectin and starch, as confirmed by FTIR and DSC. Moreover, the pectin-starch foam displayed improved mechanical properties under wet storage conditions, mainly due to the limited moisture adsorption and water migration. The foam containing 4 wt% of pectin exhibited the highest compression-recovery ratio (76.7 %) and a reduced adsorbed moisture content (19.22 %) under 95 % RH. Overall, citrus pectin could improve the starch foaming process and the foam blocks barrier properties.

Sugar inclusion influences the expansion characteristics of corn starch extrudates

Corn starch-based direct expanded products incorporated with 2% and 10% (w/w) sugar (fructose, glucose, sucrose, and xylose) were produced using a 20 mm co-rotating twin-screw extruder. The pasting and thermal properties of raw corn starch-sugar mixes were analyzed before extrusion processing. The independent variables for extrusion processing included two sugar inclusion levels (2% and 10% w/w) and two screw speeds (150 and 250 rpm). The extrudates were characterized by their initial expansion ratio (IER), expansion ratio (ER), and shrinkage. ER values were high for fructose at 2% and 150 rpm and 10% glucose and sucrose extrudates at 250 rpm. The extrudates with 2% sucrose inclusion shrunk significantly higher than the control. Fourier transform infrared (FTIR) spectroscopy of the extruded blends did not indicate the presence of any new covalent bond formed between starch and sugar post-extrusion. The interactions between sugar concentration and screw speed significantly influenced extrudate expansion characteristics. Due to their thermal and plasticizing properties, sugar inclusion (glucose, fructose, sucrose, and xylose) enhanced the extrudate expansion by altering their melt viscosity. PRACTICAL APPLICATION: The findings of this study can improve the expansion characteristics of high-fiber-based extruded snacks. Ingredients high in fiber generally hinder the starch transformation during extrusion and negatively impact the expansion properties. The presence of sugar at low concentrations can improve melt properties during extrusion processing and, in turn, significantly improve the textural properties of snacks.

The role of non-starch constituents in the extrusion processing of slow-digesting starch diets: A review

Starch is the main source of energy for the human body through diet, and its digestive properties are closely related to the occurrence of chronic diseases. Extrusion technology, which is characterized by low cost and high efficiency, has been widely used in the field of reducing starch digestibility and modifying starch, and it has great potential for designing and manufacturing precision nutrition for specific populations. However, this aspect of study has not been systemically summarized, so we systematically discuss the role of extrusion and non-starch components in starch modification in this review. This review focuses on the following sections: the effect mechanisms of extrusion on starch digestibility in terms of granule morphology, crystal structure, viscosity and pasting characteristics; the different effects of single or multiple non-starch components on starch digestibility under extrusion; and some of the current applications of extrusion technology in the development of slow-digesting starchy diets. This review summarises the effects of extrusion techniques and non-starch components on starch digestibility under extrusion conditions, and provides the appropriate theoretical basis for the application of starch-based foods in the development of slow-digesting diets, the precise nutritional design of specific populations, and the improvement of the structure of healthy human diets.

Sequential extraction of hawthorn pectin: An attempt to reveal their original mode of being in plants and functional properties

Hawthorn is rich in pectin, which is much higher than most cultivated fruits, but conventional extraction methods do not meet the requirements of low energy consumption and green production. Pectin in hawthorn is divided into soluble and insoluble parts, and with the ripening of hawthorn, the original pectin is converted into soluble pectin and pectic acid under the action of enzymes. Therefore, based on the characteristics of hawthorn pectin, this study sequentially extracted hawthorn pectin using water-soluble pectin (WSP) and hot acid-soluble pectin (HAP) method, verifying the feasibility of extracting hawthorn pectin with pure water at room temperature, and systematically analyzing and comparing the physicochemical properties and functional characteristics of the two methods. The combination of texture analysis and gel rheology revealed that WSP formed a more uniform and dense network structure during the gelation process. Additionally, microscopic observations and emulsification index results indicated that the emulsion prepared with WSP (WSE) had a smaller particle size and better stability. This indicates that hawthorn pectin is suitable for extraction with pure water at room temperature, which can maintain its good physical properties while reducing energy consumption, providing a new approach for the large-scale extraction of pectin in the food industry.

Improving the gel properties of Ficus pumila Linn. pectin by incorporating deacetylated konjac glucomannan

To improve the gelation behaviour of pectin, the effect of deacetylated konjac glucomannan (DKGM) with various deacetylation degrees (27.44 %, 44.32 %, 60.25 %, and 71.77 %) on the heat-induced gel characteristics of Ficus pumila Linn. pectin was studied. The hardness, chewiness, and adhesiveness of the gel increased as the degree of deacetylation increased from 27.44 % to 60.25 %, but decreased at 71.77 %. Additionally, DKGM addition resulted in higher apparent viscosity and non-Newtonian fluid behaviour in the composite gel. The incorporation of DKGM into the gel matrix strengthened the gel structure by promoting hydrogen bond formation and shortening relaxation time compared to the control. Scanning electron microscopy images revealed that the densification of the pectin gel network increased as the degree of deacetylation of konjac glucomannan rose from 27.44 % to 60.25 %, but then loosened when it exceeded 71.77 %. As the degree of deacetylation increased, the hydrophobic interaction between pectin and DKGM increased. Overall, the addition of DKGM effectively modulated the gel properties of Ficus pumila Linn. pectin, thus broadening its industrial application on different gel products.

Effect of hydrocolloids on starch digestion: A review

Rapidly digestible starch can increase postprandial blood sugar rapidly, which can be overcome by hydrocolloids. The paper aims to review the effect of hydrocolloids on starch digestion. Hydrocolloids used to reduce starch digestibility are mostly polysaccharides like xanthan gum, pectin, β-glucan, and konjac glucomannan. Their effectiveness is related to their source and structure, mixing mode of hydrocolloid/starch, physical treatment, and starch processing. The mechanisms of hydrocolloid action include increased system viscosity, inhibition of enzymatic activity, and reduced starch accessibility to enzymes. Reduced starch accessibility to enzymes involves physical barrier and structural orderliness. In the future, physical treatments and intensity used for stabilizing hydrocolloid/starch complex, risks associated with different doses of hydrocolloids, and the development of related clinical trials should be focused on. Besides, investigating the effect of hydrocolloids on starch should be conducted in the context of practical commercial applications rather than limited to the laboratory level.

Investigation of the mechanism of gelatin to enhance 3D printing accuracy of corn starch gel: From perspective of phase morphological changes

The study examined the impact of phase morphological transformations within the corn starch/gelatin system, induced by varying gelatin content, on its rheological properties and 3D printing performance. Gelatin addition inhibited the gelatinization and retrogradation of starch, which leaded to the transformation of continuous phase structure. The transition process from starch continuous phase to gelatin continuous phase promoted a thinner wall structure of the gel and loosed its dense network, resulting in reduced flow stress (τf) and storage modulus (G'). These changes improved the extrusion and "extrusion swelling" of gel ink materials, which made the print size of printed product closer to the set model. The formation of a gelatin continuous phase in the gel was helpful in increasing τf and G', resulting in enhanced support capacity of the printed product. This study presented meaningful information for the application of 3D printing to starch-gelatin complex foods.

Unlocking the potential of pasting properties to predict extrudate characteristics of corn grits blends with high amylose corn starch, potato starch, or rice flour

The development of new production lines of extruded ready-to-eat (RTE) snacks often results in high losses of edible food due to the trial-and-error approach in industry. Being able to predict extrudate characteristics of new formulations before having to run trials on industrial scale would be beneficial for reducing waste and having a more efficient development process. With this study, the correlation between pasting properties of seven blends of flours/starches and extrudate characteristics was investigated (100% corn grits, 25% and 50% replacement of corn grits with high amylose starch, potato starch, and rice flour). The predictive power of pasting characteristics on extrudate's moisture content, water absorption and solubility index, sectional expansion index (SEI) and hardness was studied. Results indicated the potential of predicting SEI, water solubility index (WSI), and water absorption index (WAI) of RTE-snacks. WSI and WAI were, respectively, negatively correlated with peak temperature (R2  = 0.897), and positively with peak temperature and positively with trough viscosity (R2  = 0.855). One can conclude that the rheometer can be a useful tool to gain insight into the characteristics of the extrudate, although further research with enlargement of the dataset is necessary to make the rheometer effectively deployable for potentially other extrudate characteristics.

Research progress in extraction, purification, structure of fruit and vegetable polysaccharides and their interaction with anthocyanins/starch

Fruits and vegetables contain polysaccharides, polyphenols, antioxidant enzymes, and various vitamins, etc. Fruits and vegetables polysaccharides (FVPs), as an important functional factor in health food, have various biological activities such as lowering blood sugar, blood lipids, blood pressure, inhibiting tumors, and delaying aging, etc. In addition, FVPs exhibit good physicochemical properties including low toxicity, biodegradability, biocompatibility. Increasing research has confirmed that FVPs could enhance the stability and biological activities of anthocyanins, affecting their bioavailability to improve food quality. Simultaneously, the addition of FVPs in natural starch suspension could improve the physicochemical properties of natural starch such as viscosity, gelling property, water binding capacity, and lotion stability. Hence, FVPs are widely used in the modification of natural anthocyanins/starch. A systematic review of the latest research progress and future development prospects of FVPs is very necessary to better understand them. This paper systematically reviews the latest progress in the extraction, purification, structure, and analysis techniques of FVPs. Moreover, the review also introduces the potential mechanisms, evaluation methods, and applications of the interaction between polysaccharides and anthocyanins/starch. The findings can provide important references for the further in-depth development and utilization of FVPs.

Black garlic particles as a natural pigment and emulsifier in a Pickering emulsion based low fat innovative mayonnaise: Improved rheology and bioactivity

Black garlic is rich in brown pigments and Maillard reaction products are known for antioxidant activity and health promoting effects. In the present investigation, we report a facile strategy for fabricating low-fat innovative mayonnaise (IM) using black garlic particles (BGP) as a natural pigment, and a functional ingredient. Whey protein concentrate and high methoxyl pectin at optimized concentrations were utilized for fabricating an IM which served as a control. IM5 and IM10 were ternary composites constituting whey protein, high methoxyl pectin along with BGP (@5 and 10% respectively). The formulation IM10 (BGP @10%) showed high firmness and low spreadability quotient, hence IM5 was taken forward for fabrication for two more variants namely IM-J (using low methoxyl pectin (LMP) from jackfruit peels) and IM-C (LMP from citrus). The effect of BGP and LMP on the functional quality of IM was confirmed through zeta potential, antioxidant activity, textural, rheological, and microscopic evaluation. Fluorescence microscopy confirmed the presence of solid particles over the fat phase of IM, while interaction of pectin and whey proteins was demonstrated through fluorescence emission spectroscopy which clearly displayed stabilization of IM through the formation of Pickering emulsion. Pronounced difference in color and flavor score with BGP established high sensory scores in IM5, IM-J, and IM-C. Rheology supported the stabilizing effects of LMP in IM-J and IM-C in terms of speedy recovery of thixotropy, with recovering storage modulus (G'). Enhanced viscosity of IM-C and IM-J further corroborated the dual effect of LMP and BGP in improving emulsifying and functional quality of IM. Enhanced oxidative stability of IM was established by reduced peroxide and Totox values. Overall our results suggest the promising applications of black garlic as functional ingredient in protein and pectin based Pickering emulsions.

High methoxyl pectin can improve the extrusion characteristics and increase the dietary fiber content of starch-cellulose extrudates

Improving total dietary fiber content while maintaining the texture/expansion of extruded products is a challenge. Pectin has a dual function; it is a source of dietary fiber and it also functions as a hydrocolloid, which could improve the texture of high-fiber extruded foods. The objective of this study was to evaluate the impacts of pectin types from citrus peel on the expansion characteristics of starch-cellulose extrudates. High and low methoxyl pectin (HMP and LMP) was added to the starch-cellulose mixtures and extruded using a twin-screw extruder. The pasting properties of raw mixtures, extrusion properties, microstructure, and dietary fiber contents of the extrudates were studied. The inclusion of HMP in raw material improved the peak viscosity (629.7 ± 8.1 to 754.7 ± 80.1 mPa s) and maintained the final viscosity compared to the control (starch-cellulose mixture alone), unlike LMP. HMP relatively maintained the extrusion process parameters such as torque, back pressure, and specific mechanical energy as the control. Interestingly, the addition of 7% of HMP had a similar expansion ratio (3.41 ± 0.08 to 2.35 ± 0.06) compared to the control (3.46 ± 0.08 to 2.32 ± 0.09) under the extrusion conditions studied. The total dietary fiber content improved from 12.22 ± 0.01% to 18.26 ± 0.63% (w/w). HMP maintained the expansion characteristic of starch-cellulose extrudates and improved its total dietary fiber content relative to LMP. Adding HMP to the mixtures improved the extensibility of the melt, favoring bubble growth and expansion of the starch-cellulose extrudates. Fourier transform infrared spectroscopy data suggested that there could be intermolecular interactions between starch, cellulose, and pectin, but the nature of these interactions needs further investigation. PRACTICAL APPLICATION: The study provides practical information on the influence of the addition of high and low methoxyl pectin on starch-cellulose extrudates. The results can help the industry to produce snack products that are more nutritious but are still well accepted by the consumers.

High-shear wet agglomeration process for enriching cornstarch with curcumin and vitamin D3 co-loaded lyophilized liposomes

Curcumin and vitamin D₃ are bioactive molecules of great importance for the food industry. However, their low stability in several processing conditions hampers their proper incorporation into powdered food formulations. This study proposes the enrichment of a common raw material (cornstarch) with curcumin and vitamin D₃ by using high-shear wet agglomeration. The bioactives were initially encapsulated into liposome dispersions and then subjected to lyophilization. The resulting dried vesicles were later incorporated into cornstarch by wet agglomeration using maltodextrin as the binder solution. The phospholipid content and the amount of added liposomes were evaluated to characterize the enriched cornstarch samples. The lyophilized vesicles showed a high retention rate of 99 % for curcumin and vitamin D₃, while the enriched cornstarch samples retained above 96 % (curcumin) and 98 % (vitamin D₃) after 30 days of controlled storage. All in all, the presence of dried liposomes improved the flowability and delayed retrogradation phenomenon in agglomerated cornstarch. Therefore, this study introduced a novel and reliable method of incorporating hydrophobic and thermosensitive molecules into powdered food formulations by using readily available materials and a straightforward high-shear wet agglomeration process.

Characterize the physicochemical properties and microstructure of pectin from high-pressure and thermal processed cloudy hawthorn (Crataegus pinnatifida) juice based on acid heating extraction

Physicochemical properties and morphological features of pectin in high-pressure-processing (JHPP) and thermal-processing (JTP) treated cloudy hawthorn juice were investigated based on acid heating extraction. Pectin from hawthorn juice was identified as low methoxy pectin (41.77%), which was significantly reduced to 34.56%-39.51% from JHPP, while pectin esterification degree (DE) from JTP increased to 45.58%, which can also be confirmed by Fourier transform infrared spectroscopy. In comparison to control, pectin linearity of JHPP and JTP significantly decreased with more highly branched-chains. However, no significate difference was observed in thermostability, crystallinity and main functional groups. Interestingly, a large number of aggregations was observed in JHPP pectin, and the intermodular distance of JTP pectin was enhanced, which was consistent with the results of viscosity, molecular weight and DE. These findings provided insights into utilization of hawthorn pectin and application of high-pressure processing (HPP) for improving quality property of fruit products by pectin modification.

Influence of starch with different degrees and order of gelatinization on the microstructural and mechanical properties of pectin cryogels: A potential pore morphology regulator

The applications of cryogels are defined by their porous morphology as well as mechanical properties. To achieve efficient regulation of porous properties for pectin cryogels, we selected starch as a potential polysaccharide regulator. Pectin/starch composite cryogels with different degrees of gelatinization were formulated, and two ways of starch gelatinization were considered: starch gelatinization occurred before or after pectin crosslinking during forming the hydrogel network. The results showed that high gelatinized starch (73.8 %-100.0 %) rendered pectin cryogels with denser pore morphology and higher mechanical strength. The pore diameter transferred from 160-200 μm to 40-60 μm with the degree of gelatinization, while the total porosity decreased by about 15 % and the specific surface area increased by about 100 m²/g. When starch gelatinization occurred before pectin crosslinking, the hydrogen bond interactions between gelatinized starch and pectin were formed to accelerate the gelation rate of the pectin Ca²⁺-dependent network. When gelatinization occurred after pectin crosslinking, the pre-formed pectin network delayed the breakdown of the starch crystalline structure during gelatinization. The qualitative regulation of the pore morphology in pectin cryogels by incorporating starches with varying degrees of gelatinization was confirmed.

Comparative study of water-soluble polysaccharides isolated from leaves and roots of Isatis indigotica Fort

Water-soluble polysaccharides were isolated from the leaves and roots of Isatis indigotica Fort., and their structural features were studied and compared. One neutral polysaccharide fraction (WFIP-N) and three pectin fractions (WFIP-A-A, WFIP-A-B and WFIP-A-C) were obtained from the leaves, and one neutral polysaccharide fraction (WRIP-N) and two pectin fractions (WRIP-A-A and WRIP-A-B) were obtained from the roots. WFIP-A-B (Mw = 34.6 kDa) and WRIP-A-B (Mw = 29.9 kDa) were the major pectic polysaccharides. Monosaccharide composition, FT-IR, enzymatic hydrolysis, NMR and methylation analysis indicated that both WFIP-A-B and WRIP-A-B are composed of rhamnogalacturonan I (RG-I), rhamnogalacturonan II (RG-II) and homogalacturonan (HG) domains with mass ratios of 1.5:1.0:0.4 and 0.3:1.0:1.7, respectively. WFIP-A-B and WRIP-A-B were found to be rich in RG-I and HG domains, respectively, and mainly contained type II arabinogalactan (AG-II) and α-L-1,5-arabinan side chains, but those in WRIP-A-B were more numerous and longer. Our results provide structural features and differences between these polysaccharides which will help to elucidate their functional differences.

Pectin Microspheres: Synthesis Methods, Properties, and Their Multidisciplinary Applications

There is great contemporary interest in using cleaner technologies through green chemistry and utilizing biopolymers as raw material. Pectin is found on plant cell walls, and it is commonly extracted from fruit shells, mostly apples or citrus fruits. Pectin has applications in many areas of commercial relevance; for this reason, it is possible to find available information about novel methods to transform pectin and pursuing enhanced features, with the structuring of biopolymer microspheres being highly cited to enhance its activity. The structuring of polymers is a technique that has been growing in recent decades, due to its potential for diverse applications in various fields of science and technology. Several techniques are used for the synthesis of microspheres, such as ionotropic gelation, extrusion, aerosol drying, or emulsions, with the latter being the most commonly used method based on its reproducibility and simplicity. The most cited applications are in drug delivery, especially for the treatment of colon diseases and digestive-tract-related issues. In the industrial field, it is used for protecting encapsulated compounds; moreover, the environmental applications mainly include the bioremediation of toxic substances. However, there are still many possibilities for expanding the use of this biopolymer in the environmental field.

Effect of Sand-Frying-Triggered Puffing on the Multi-Scale Structure and Physicochemical Properties of Cassava Starch in Dry Gel

This study revealed the underlying mechanisms involved in the puffing process of dried cassava starch gel by exploring the development of the puffed structure of gel upon sand-frying, chiefly focused on the changes in the multi-scale structure and the physicochemical properties of starch. The results suggested that the sand-frying-induced puffing proceeded very fast, completed in about twenty seconds, which could be described as a two-phase pattern including the warming up (0~6 s) and puffing (7~18 s) stages. In the first stage, no significant changes occurred to the structure or appearance of the starch gel. In the second stage, the cells in the gel network structure were expanded until burst, which brought about a decrease in moisture content, bulk density, and hardness, as well as the increase in porosity and crispness when the surface temperature of gel reached glass transition temperature of 125.28 °C. Upon sand-frying puffing, the crystalline melting and molecular degradation of starch happened simultaneously, of which the latter mainly occurred in the first stage. Along with the increase of puffing time, the thermal stability, peak viscosity, and final viscosity of starch gradually decreased, while the water solubility index increased. Knowing the underlying mechanisms of this process might help manufacturers produce a better quality of starch-based puffed products.

Effect of Structurally Different Pectin on Dough Rheology, Structure, Pasting and Water Distribution Properties of Partially Meat-Based Sugar Snap Cookies

Pectin has been widely used as a hydrocolloid in foods, but its effectiveness based on hydrodynamics radius (Rh), average side chain length (ACL) and degree of esterification (DE) has been less studied. This study investigated the effect of 4 types of pectin (with different molecular weight and structures) at a level of 1.5% w/w of wheat flour on functional, structural and water binding properties of sugar snap cookies partially substituted with fish meat. The results showed that pectin (CU-201 and CU-601) with higher ACL and Rh controlled excessive expansion, while the improved rheology of dough in terms of behavior as viscous matrix compared to control and other pectin. Texture was found to be highly dependent on Rh and ACL compared to DE of pectin. The pasting properties, especially peak viscosity and final viscosity, were significantly (p < 0.05) increased with increasing DE, as well as ACL, by entangling and increasing the interaction between starch and pectin. The scanning electron microscopy (SEM) analysis exhibited that control sample showed wide voids and more intercellular spaces, while samples prepared with CU-601, CU-201, and CUL displayed compact structure, which was also evidenced by controlled expansion and improved hardness of the cookies. Low field nuclear magnetic resonance (LF-NMR) analysis showed that T21 relaxation time and amplitude were found to be shorter for CU-601 and CU-201 treatments, signifying the high amount of tightly bound water compared to control. The findings endorse the feasibility of adding CU-601, and CU-201 as an efficient hydrocolloid for the improved structural and functional properties of cookies.

Effects of Pectin on the Physicochemical Properties and Freeze-Thaw Stability of Waxy Rice Starch

In this study, the effects of the addition of pectin (PEC) on the physicochemical properties and freeze-thaw stability of waxy rice starch (WRS) were investigated. As PEC content increased, the pasting viscosity and pasting temperature of WRS significantly increased (p < 0.05), whereas its breakdown value and setback value decreased. Differential scanning calorimetry showed that the addition of PEC increased the gelatinization temperature of WRS, but decreased its gelatinization enthalpy. Rheological measurements indicated that the addition of PEC did not change the shear-thinning behavior of WRS-PEC blends, and the storage modulus and loss modulus were positively correlated with PEC content. Moreover, the textural parameter of WRS decreased with the increase in PEC content. Furthermore, the addition of PEC decreased the transmittance of starch paste, but enhanced the freeze-thaw stability of WRS to some extent. These results may contribute to the development of WRS-based food products.

Delineating the inherent functional descriptors and biofunctionalities of pectic polysaccharides

Pectin is a plant-based heteropolysaccharide macromolecule predominantly found in the cell wall of plants. Pectin is commercially extracted from apple pomace, citrus peels and sugar beet pulp and is widely used in the food industry as a stabilizer, emulsifier, encapsulant, and gelling agent. This review highlights various parameters considered important for describing the inherent properties and biofunctionalities of pectins in food systems. These inherent descriptors include monosaccharide composition, galacturonic acid content, degree of esterification, molecular weight, structural morphology, functional group analysis, and functional properties, such as water and oil holding capacity, emulsification, foaming capacity, foam stability, and viscosity. In this study, we also delineate their potential as a nutraceutical, prebiotic, and carrier for bioactive compounds. The biofunctionalities of pectin as an anticancer, antioxidant, lipid-lowering, and antidiabetic agent are also conceptually elaborated in the current review. The multidimensional characteristics of pectin make it a potential candidate for use in food and biomedical science.

Utilization of Food Processing By-products in Extrusion Processing: A Review

The processing of agricultural products into value-added food products yields numerous by-products or waste streams such as pomace (fruit and vegetable processing), hull/bran (grain milling), meal/cake (oil extraction), bagasse (sugar processing), brewer's spent grain (brewing), cottonseed meal (cotton processing), among others. In the past, significant work in exploring the possibility of the utilization of these by-products has been performed. Most by-products are highly nutritious and can be excellent low-cost sources of dietary fiber, proteins, and bioactive compounds such as polyphenols, antioxidants, and vitamins. The amount of energy utilized for the disposal of these materials is far less than the energy required for the purification of these materials for valorization. Thus, in many cases, these materials go to waste or landfill. Studies have been conducted to incorporate the by-products into different foods in order to promote their utilization and tackle their environmental impacts. Extrusion processing can be an excellent avenue for the utilization of these by-products in foods. Extrusion is a widely used thermo-mechanical process due to its versatility, flexibility, high production rate, low cost, and energy efficiency. Extruded products such as direct-expanded products, breakfast cereals, and pasta have been developed by researchers using agricultural by-products. The different by-products have a wide range of characteristics in terms of chemical composition and functional properties, affecting the final products in extrusion processing. For the practical applications of these by-products in extrusion, it is crucial to understand their impacts on the qualities of raw material blends and extruded products. This review summarizes the general differences in the properties of food by-products from different sources (proximate compositions, physicochemical properties, and functional properties) and how these properties and the extrusion processing conditions influence the product characteristics. The discussion of the by-product properties and their impacts on the extrudates and their nutritional profile can be useful for food manufacturers and researchers to expand their applications. The gaps in the literature have been highlighted for further research and better utilization of by-products with extrusion processing.