Enzymatic Interesterification of Palm Stearin, Flaxseed Oil and Cottonseed Stearin to Produce Stable Plastic Fat with Balanced Omega-6 and Omega-3 Fatty Acids.

This study aimed to produce stable plastic fat with desired physicochemical characteristics and ω-6/ω-3 fatty acid ratio (1:1-4:1) from palm stearin (PS), flaxseed oil (FSO) and cottonseed stearin (CS) via enzymatic interesterification (EIE). For the first time, the EIE variables of the blends containing PS, FSO and CS were investigated and optimized through single-factor experiments and response surface design to achieve a high interesterification degree. The optimized enzymatic interesterification conditions were: 60°C, 6 wt% Lipase UM1, and 6 h. Lipase UM1 had a similar effect on ID values with commercial lipases. The EIE improved the compatibility of the lipid blends, with the interesterified product EIE-721 (7:2:1, PS: FSO:CS) being the best candidate base stock for shortening considering its solid fat content, desired ω-6/ω-3 fatty acid ratio, wide melting range, abundant ß' form crystal, and compact microstructure. This study provides a strategy to produce balanced ω-6/ω-3 fatty acid plastic fat through enzymatic interesterification and validates the application of Lipase UM1 in the preparation of plastic fat.

Food packaging films based on ionically crosslinked konjac glucomannan incorporating zein-pectin nanoparticle-stabilized corn germ oil-oregano oil Pickering emulsion.

This study addresses the limitations of konjac glucomannan (KGM) films in mechanical properties, hydrophobicity and antibacterial activities. For the first time, a zein-pectin nanoparticle-stabilized corn germ oil-oregano essential oil Pickering emulsion (ZPCEO) was incorporated into KGM, with the resulting film being further ionically crosslinked with Ca2+, Cu2+ or Fe3+. FTIR, SEM and EDS results showed that the metal ions were crosslinked with the hydroxyl and carbonyl groups of polysaccharides and uniformly distributed throughout the films (degree of crosslinking: Fe3+ > Cu2+ > Ca2+). Compared with pure KGM films, the ionic crosslinked ZPCEO/KGM (IL-ZPCEO/KGM) films have superior water resistance mechanical properties, and exhibit unique UV-blocking properties, antioxidant and antibacterial activities. The ZPCEO/KGM-Fe3+ film offered the best all-round properties, including the highest tensile strength, water resistance, UV-blocking capacity, and antimicrobial activity. Thus, ionic crosslinking of ZPCEO/KGM films can be applied to the preparation of food packaging for use in high humidity environments.

Garlic polysaccharide-Cr (III) complexes with enhanced in vitro and in vivo hypoglycemic activities.

This study aimed to prepare a complex of Cr (III) and garlic polysaccharides (GPs) and evaluate the in vitro and in vivo hypoglycemic activities of GPs and GP-Cr (III) complexes. The chelation of GPs with Cr (III) increased molecular weight, modified crystallinity, and altered morphological characteristics, through targeting the OH of hydroxyl groups and involving the C-O/O-C-O structure. The GP-Cr (III) complex had a higher thermal stability over 170-260 °C and higher stability throughout the gastrointestinal digestion. In vitro, the GP-Cr (III) complex exhibited a significantly stronger inhibitory effect against α-glucosidase compared with the GP. In vivo, the GP-Cr (III) complex at a high dose (4.0 mg Cr/kg body weight) generally had a higher hypoglycemic activity than the GP in (pre)-diabetic mice induced by a high-fat and high-fructose diet, based on indices like body weight, blood glucose levels, glucose tolerance, insulin resistance, insulin sensitivity, blood lipid levels, and hepatic morphology and function. Therefore, GP-Cr (III) complexes could be a potential Cr (III) supplement with an enhanced hypoglycemic activity.

Recent advances in utilization of pectins in biomedical applications: a review focusing on molecular structure-directing health-promoting properties.

The numerous health benefits of pectins justify their inclusion in human diets and biomedical products. This review provides an overview of pectin extraction and modification methods, their physico-chemical characteristics, health-promoting properties, and pharmaceutical/biomedical applications. Pectins, as readily available and versatile biomolecules, can be tailored to possess specific functionalities for food, pharmaceutical and biomedical applications, through judicious selection of appropriate extraction and modification technologies/processes based on green chemistry principles. Pectin's structural and physicochemical characteristics dictate their effects on digestion and bioavailability of nutrients, as well as health-promoting properties including anticancer, immunomodulatory, anti-inflammatory, intestinal microflora-regulating, immune barrier-strengthening, hypercholesterolemia-/arteriosclerosis-preventing, anti-diabetic, anti-obesity, antitussive, analgesic, anticoagulant, and wound healing effects. HG, RG-I, RG-II, molecular weight, side chain pattern, and degrees of methylation, acetylation, amidation and branching are critical structural elements responsible for optimizing these health benefits. The physicochemical characteristics, health functionalities, biocompatibility and biodegradability of pectins enable the construction of pectin-based composites with distinct properties for targeted applications in bioactive/drug delivery, edible films/coatings, nano-/micro-encapsulation, wound dressings and biological tissue engineering. Achieving beneficial synergies among the green extraction and modification processes during pectin production, and between pectin and other composite components in biomedical products, should be key foci for future research.

Physicochemical, structural and emulsifying properties of RG-I enriched pectin extracted from unfermented or fermented cherry pomace.

This study explores cherry waste valorization through sustainable green approaches. Two low-methoxy rhamnogalacturonan I (RG-I) enriched pectins were produced via mild aqueous extraction from cherry pomaces before and after yeast fermentation (RCUP and RCFP: RG-I, 52.02% and 48.81%; methylation degree, 44.71% and 37.55%). Both pectins contained galacturonic acid, arabinose, galactose, rhamnose and glucose. Compared with RCFP, RCUP was a more linear pectin with higher Mw, wider Mw distribution, longer homogalacturonans (HGs) and shorter side chains. Fermentation increased protein, mannose, glucose and galactose contents, and decreased pectin yield, total phenolic/anthocyanin and rhamnose contents, melting temperature and enthalpy, degradation enthalpy, viscosity, storage and loss moduli. Fermentation induced a much greater loss of HG (from 43.55% to 14.65%) than RG-I (from 52.02% to 48.81%). RCUP and RCFP possessed significant antioxidant activities and exhibited satisfactory emulsifying effects at 2%. RCUP was a more effective emulsifier. RCFP had a higher hydroxyl radical scavenging capacity.

Protective effects of the phenolic compounds from mung bean hull against H2O2-induced skin aging through alleviating oxidative injury and autophagy in HaCaT cells and HSF cells.

To add value to food waste and seek skin aging suppressor, petroleum ether, ethyl acetate, n-butanol and water phenolic extracts were produced from mung bean hulls subjected to ultrasound-assisted ethanolic extraction. The four extracts all contained protocatechuic acid, isovitexin, vitexin, caffeic acid, 4-coumaric acid, ferulic acid, rutin and chlorogenic acid (revealed by UHPLC-MS/MS). The effects of the four extracts and their main phenolic compounds against H2O2-caused cell damage and aging in HaCaT and HSF cells were examined (including cell viability, ROS, MDA, SOD, GSH-px and ß-galactosidase levels). The four extracts and the eight phenolic compounds exhibited different protective effects on H2O2-treated HaCaT/HSF cells viability, with the ethyl acetate extract among the extracts, and isovitexin and vitexin among the eight compounds, exerting the greatest protection. Therefore, isovitexin and vitexin may be the key oxidative stress and autophagy modulators of mung bean hull, and they inhibit skin aging and damage likely through suppressing Nrf2/keap1/HO-1 related oxidative damage and LC3II/p62/GATA4 related autophagy.

Bioactive polysaccharides and oligosaccharides from garlic (Allium sativum L.): Production, physicochemical and biological properties, and structure-function relationships.

Garlic is a common food, and many of its biological functions are attributed to its components including functional carbohydrates. Garlic polysaccharides and oligosaccharides as main components are understudied but have future value due to the growing demand for bioactive polysaccharides/oligosaccharides from natural sources. Garlic polysaccharides have molecular weights of 1 × 103 to 2 × 106  Da, containing small amounts of pectins and fructooligosaccharides and large amounts of inulin-type fructans ((2→1)-linked ß-d-Fruf backbones alone or with attached (2→6)-linked ß-d-Fruf branched chains). This article provides a detailed review of research progress and identifies knowledge gaps in extraction, production, composition, molecular characteristics, structural features, physicochemical properties, bioactivities, and structure-function relationships of garlic polysaccharides/oligosaccharides. Whether the extraction processes, synthesis approaches, and modification methods established for other non-garlic polysaccharides are also effective for garlic polysaccharides/oligosaccharides (to preserve their desired molecular structures and bioactivities) requires verification. The metabolic processes of ingested garlic polysaccharides/oligosaccharides (as food ingredients/dietary supplements), their modes of action in healthy humans or populations with chronic conditions, and molecular/chain organization-bioactivity relationships remain unclear. Future research directions related to garlic polysaccharides/oligosaccharides are discussed.

The potential of dandelion in the fight against gastrointestinal diseases: A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Dandelion (Taraxacum officinale Weber ex F. H. Wigg.), as a garden weed grown globally, has long been consumed as a therapeutic herb. Its folkloric uses include treatments of digestive disorders (dyspepsia, anorexia, stomach disorders, gastritis and enteritis) and associate complex ailments involving uterine, liver and lung disorders. AIM OF THE STUDY: The present study aims to critically assess the current state of research and summarize the potential roles of dandelion and its constituents in gastrointestinal (GI) -protective actions. A focus is placed on the reported bioactive components, pharmacological activities and modes of action (including molecular mechanisms and interactions among bioactive substances) of dandelion products/preparations and derived active constituents related to GI protection. MATERIALS AND METHODS: The available information published prior to August 2021 was reviewed via SciFinder, Web of Science, Google Scholar, PubMed, Elsevier, Wiley On-line Library, and The Plant List. The search was based on the ethnomedical remedies, pharmacological activities, bioactive compounds of dandelion for GI protection, as well as the interactions of the components in dandelion with the gut microbiota or biological regulators, and with other ingested bioactive compounds. The key search words were "Taraxacum" and "dandelion". RESULTS: T. coreanum Nakai, T. mongolicum and T. officinale are the most commonly used species for folkloric uses, with the whole plant, leaves and root of dandelion being used more frequently. GI-protective substances of dandelion include taraxasterol, taraxerol, caffeic acid, chicoric acid, chlorogenic acid, luteolin and its glucosides, polysaccharides, inulin, and ß-sitosterol. Dandelion products and derived constituents exhibit pharmacological effects against GI disorders, mainly including dyspepsia, gastroesophageal reflux disease, gastritis, small intestinal ulcer, ulcerative colitis, liver diseases, gallstones, acute pancreatitis, and GI malignancy. The underlying molecular mechanisms may include immuno-inflammatory mechanisms, apoptosis mechanism, autophagy mechanism, and cholinergic mechanism, although interactions of dandelion's constituents with GI health-related biological entities (e.g., GI microbiota and associated biological modulators) or other ingested bioactive compounds shouldn't be ignored. CONCLUSION: The review reveals some in vivo and in vitro studies on the potential of dandelion derived products as complementary and alternative medicines/therapeutics against GI disorders. The whole herb may alleviate some symptoms related GI immuno-inflammatory basing on the abundant anti-inflammatory and anti-oxide active substances. Dandelion root could be a nontoxic and effective anticancer alternative, owing to its abundant terpenoids and polysaccharides. However, research related to GI protective dandelion-derived products remains limited. Besides the need of identifying bioactive compounds/complexes in various dandelion species, more clinical studies are also required on the metabolism, bioavailability and safety of these substances to support their applications in food, medicine and pharmaceuticals.

Apple phenolic extracts ameliorate lead-induced cognitive impairment and depression- and anxiety-like behavior in mice by abating oxidative stress, inflammation and apoptosis via the miR-22-3p/SIRT1 axis.

Lead can lead to neurotoxicity and cognitive impairment. In this study, for the first time, the protective effects and working mechanisms of apple phenolic extracts (APEs) against lead acetate (Pb(Ac)2)-induced cognitive impairment and depression- and anxiety-like behavior were examined in vivo. Forty male mice were administered daily (via gastric gavage; 8 weeks) with 0.9% normal saline (control), Pb(Ac)2 (20 ppm), APE (200 ppm) or Pb(Ac)2 (20 ppm) + APE (200 ppm). The APE contained five major phenolic compounds: chlorogenic acid, proanthocyanidin B2, epicatechin, phloridzin and phloretin. Behavioral tests, histopathological examinations and biochemical analyses revealed that Pb(Ac)2-treated mice exhibited cognitive and behavioral deficits (i.e. a reduced percentage of spontaneous alternation, prolonged duration of immobility and decreased open field test scores compared with the control. Pb(Ac)2 exposure significantly increased cellular oxidative damage and the levels of pro-inflammatory cytokines (interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α), ionized calcium binding adaptor molecule 1 (Iba1) and pro-apoptotic proteins (caspase 3, caspase 9 and Bax), while downregulating the expression of Bcl-2 in the brain. APE administration alleviated these Pb(Ac)2-induced changes through regulating oxidative stress, neuroinflammation and apoptosis via the miR-22-3p/Sirtuin 1 (SIRT1) signaling pathway. Taken together, the APE has the potential to treat lead-induced neurotoxicity and neurodegenerative disorders via antioxidant, anti-inflammatory and anti-apoptotic actions.

Formation, nutritional value, and enhancement of characteristic components in black garlic: A review for maximizing the goodness to humans.

Black garlic (BG) is essentially a processed food and obtained through the transformation of fresh garlic (FG) (Allium sativum L.) via a range of chemical reactions (including the Maillard reaction) and microbial fermentation. This review provides the up-to-date knowledge of the dynamic and complicated changes in major components during the conversion of FG to BG, including moisture, lipids, carbohydrates (such as sugars), proteins, organic acids, organic sulfur compounds, alkaloids, polyphenols, melanoidins, 5-hydroxymethylfurfural, vitamins, minerals, enzymes, and garlic endophytes. The obtained evidence confirms that BG has several advantages over FG in certain product attributes and biological properties (especially antioxidant activity), and the factors affecting the quality of BG include the type and characteristics of FG and processing technologies and methods (especially pretreatments, and processing temperature and humidity). The interactions among garlic components, and between garlic nutrients and microbes, as well as the interplay between pretreatment and main manufacturing process, all determine the sensory and nutritional qualities of BG. Before BG is marketed as a novel snack or functional food, more research is required to fill the knowledge gaps related to quantitative monitoring of the changes in metabolites (especially those taste-active and/or biological-active substances) during BG manufacturing to maximize BG's antioxidant, anticancer, antiobesity, anti-inflammatory, immunostimulatory, anti-allergic, hepatoprotective, cardioprotective and oxidative stress-/hangover syndrome-reducing functions, and beneficial effects on memory/nervous systems. Assessments of the quality, efficacy, and safety of BG should be performed considering the impacts of BG production conditions, postproduction handling, and intake methods.

Antioxidative pectin from hawthorn wine pomace stabilizes and protects Pickering emulsions via forming zein-pectin gel-like shell structure.

The development of natural and biodegradable polymer nanoparticles as Pickering emulsion stabilizers has attracted increasing interest. In this study, antioxidative pectin from hawthorn wine pomace (HP) was first produced. HP and zein-nanoparticles (ZPs) were used to fabricate zein-HP composite nanoparticles (ZHPs) via hydrogen bonding and electrostatic interaction. The ZHP composite at the HP-ZP ratio of 1:1 (w/w) exhibited near-neutral wettability (92.9o ± 1.01), thereby being used for stabilizing Pickering emulsion (ZHPEs). CLSM and cryo-SEM showed the anchoring of ZHPs onto the surface of oil droplets and the gel-like network structure in the continuous-phase. ZHPEs at 0.5-0.7 (v/v) oil fractions were pseudoplastic fluids with elastic-solid characteristics. ZHPEs with 0.6 and 0.7 (v/v) oil fractions showed excellent thermal stability 20-60 °C. The antioxidant capacity of HP helped protect the Pickering emulsion against its lipid oxidation. Therefore, antioxidative polysaccharides could stabilize Pickering emulsions as particle shell-materials while offering protection on lipid components against oxidation. This study has demonstrated the sustainable utilization of food waste for producing value-added products.

Addition of milk to tea infusions: Helpful or harmful? Evidence from in vitro and in vivo studies on antioxidant properties.

Tea consumption is practised as a tradition, and has shown potential to improve human health. Maximal uptake of tea antioxidants and milk proteins without a negative impact on tea flavor is highly desired by consumers. There is a conflicting evidence of the effect of milk addition to tea on antioxidant activity. Differences in the type of tea, the composition, type and amount of milk, preparation method of tea-milk infusions, the assays used to measure antioxidant activity, and sampling size likely account for different findings. Interactions between tea polyphenols and milk proteins, especially between catechins and caseins, could account for a decrease in antioxidant activity, although other mechanisms are also possible, given the similar effects between soy and bovine milk. The role of milk fat globules and the milk fat globule membrane surface is also important when considering interactions and loss of polyphenolic antioxidant activity, which has not been addressed in the literature.

Physicochemical properties of peanut oil-based diacylglycerol and their derived oil-in-water emulsions stabilized by sodium caseinate.

High purity peanut oil-based diacylglycerol (PO-DAG) (94.95 wt%) was prepared via enzymatic glycerolysis from peanut oil (PO). The resulting dominance of DAGs was proven to greatly influence the properties of corresponding fresh or frozen-thawed emulsions. Stable fresh oil-in-water emulsions were produced using either PO-DAG or PO, with stability enhanced by increased concentrations of Na-CN. The lower equilibrium interfacial tension along with greater negative ζ-potential of PO revealed that Na-CN was preferentially adsorbed to the PO interface. Adding 0.05 mol/L NaCl to the PO emulsions minimized depletion flocculation caused by the unadsorbed Na-CN, but further NaCl addition increased oil droplet size and concomitant coalescence. For the PO-DAG emulsions, adding 0.2 mol/L NaCl did not significantly (p>0.05) affect their ζ-potential but adding 0.05 or 0.1 mol/L NaCl lowered ζ-potential, although NaCl at these concentrations increased oil droplet size and coalescence. Freezing-thawing process considerably weakened the stability of PO-DAG emulsions.

Absorption and desorption behaviour of the flavonoids from Glycyrrhiza glabra L. leaf on macroporous adsorption resins.

The kinetics of adsorption and desorption behaviours of five macroporous resins for enriching flavonoids from Glycyrrhizaglabra L. leaf were investigated. All five resins showed similar and effective adsorption and desorption properties. A pseudo-second-order kinetics model was suitable for evaluating the whole adsorption process. Additionally, two representative resins (XAD-16 and SP825) were chosen for adsorption thermodynamics study. The adsorption of the representative resins was an exothermic and physical adsorption process. Further column chromatography of XAD-16 and SP825 showed that the total flavonoids (from 16.8% to 55.6% by XAD-16 and to 53.9% by SP825) and pinocembrin (from 5.49% to 15.2% by XAD-16 and to 19.8% by SP825) were enriched in 90% ethanol fractions. Meanwhile, the antioxidant capacities and nitrite-scavenging capacities were 2-3times higher than those of the crude extract. The fractions with high flavonoid and pinocembrin contents could be used as biologically active ingredients in functional food.

In vitro and in vivo studies on adlay-derived seed extracts: phenolic profiles, antioxidant activities, serum uric acid suppression, and xanthine oxidase inhibitory effects.

This study aimed to explore the potential of polished adlay, brown adlay, adlay bran, and adlay hull to prevent and treat hyperuricemia. Brown adlay extract effectively decreased the serum uric acid levels of oxonate-induced hyperuricemic rats. Free and bound phenolic extracts from these materials contained significant amounts of phenolics, with free phenolics dominated by chlorogenic acid and p-coumaric acid while bound phenolics dominated by p-coumaric acid and ferulic acid. Free and bound phenolics of adlay bran exhibited significant xanthine oxidase inhibition activities, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities, oxygen radical absorbance capacities, and superoxide radical scavenging activities. Adlay bran phenolics could be effective xanthine oxidase inhibitors and radical scavengers. p-Coumaric acid is a xanthine oxidase inhibitor with strong superoxide radical scavenging activity. However, ferulic acid is a xanthine oxidase inhibitor with weak superoxide radical scavenging activity. Chlorogenic acid is a superoxide radical scavenger with weak xanthine oxidase inhibitory activity.

Delivery of green tea catechin and epigallocatechin gallate in liposomes incorporated into low-fat hard cheese.

The encapsulation of green tea catechin and epigallocatechin gallate (EGCG) in soy lecithin liposomes was examined at four concentrations (0%, 0.125%, 0.25% and 0.5% w/v), and inclusion in cheese at 0% and 0.25% w/v. The empty capsules had a mean diameter of 133nm and significantly (p<0.05) increased with the addition of catechin or EGCG. Electron microscopy revealed the lamellae and central core of the liposomes. Addition of antioxidants gave a significant (p<0.05) increase in the size of liposomes. Liposomes had surface potentials of -42.4 to -46.1mV with no significant difference between treatments, suggesting stable liposome systems. High efficiency (>70%) and yield (∼80%) were achieved from the incorporation of catechin or EGCG inside the liposome structure. Addition of either antioxidant increased the liposome phase transition temperature (>50°C). Nanocapsules containing these antioxidants were effectively retained within a low-fat hard cheese, presenting a simple and effective delivery vesicle for antioxidants.

Stability of canola oil encapsulated by co-extrusion technology: effect of quercetin addition to alginate shell or oil core.

This study examines the co-extrusion encapsulation of canola oil by alginate, with an antioxidant (quercetin) incorporated either in the oil core or alginate shell. Optical and environmental scanning electron microscopy revealed spherical beads of diameter ∼350µm and wall thickness ∼65µm. Bead appearance, size, wall thickness and surface characteristics did not change appreciably after treatments at pH 3 for 2h, pH 6.5 for 2h or pH 6.5 for 1min then pH 3 for 2h, although the amounts of phenolics released from beads differed depending on the conditions. The quercetin addition approach strongly influenced the stability of canola oil during storage at 20 and 38°C. Quercetin in the core more effectively suppressed oil deterioration. Quercetin in shell caused a higher phenolic content after storage. FTIR and HPLC analyses were used to track changes in the chemical composition of the encapsulated oil beads during storage.

Physicochemical properties of bread dough and finished bread with added pectin fiber and phenolic antioxidants.

UNLABELLED: Comparative studies were conducted in this paper to investigate the effects of added dietary fiber (DF) and/or phenolic antioxidants on the properties of bread dough and finished bread. Breads were developed in the absence (control bread), or presence of apple pectin and/or fruit phenolic extracts (treated breads), and subjected to quality evaluation (attributes including color, weight, and volume) and characterization of chemical and rheological properties. Chemical analyses revealed that breads with added phenolic extracts had greater antioxidant activity and higher extractable phenolic content, than control bread and the treated breads with added apple pectin(s). The measured antioxidant activity was mainly derived from the phenolics present in bread. Storage modulus G' (elasticity) and loss modulus G″ (viscocity) of the treated bread dough with added pectin(s) only were higher than those of control dough. The G' or G″ of the treated breads incorporated with a combination of a pectin and fruit phenolic extract depended on the type of phenolic extract (that is, apple and blackcurrant extracts behaved differently from kiwifruit extract). The G' and G″ at the final baking step were higher than those of other stages, indicating an increase in cross-linking among polymeric molecules and bread particles of high molecular weight. We conclude that the added pectin and/or phenolic extract had influenced bread dough cross-linking microstructure and bread properties through being involved in the interactions with bread components such as wheat proteins during dough development and bread baking. PRACTICAL APPLICATION: Dietary fibers and phytochemicals (including phenolic antioxidants) have long been recognized as the active nutrients responsible for the health benefits of fruit and vegetables to humans. Interest in incorporating bioactive ingredients such as dietary fiber and phenolic antioxidants into popular foods like bread has grown rapidly, due to the increased consumer health awareness. The added bioactive ingredients may or may not promote the development of bread dough. This paper reports the findings associated with the properties of the functional breads enhanced with apple pectin and apple, blackcurrant, and kiwifruit phenolic extracts. Results of this paper indicate that the success of the development of such functional breads is ultimately determined by the interactions among added bioactive ingredients and other bread components.

Kiwifruit-based polyphenols and related antioxidants for functional foods: kiwifruit extract-enhanced gluten-free bread.

The present study investigates the production of gluten-free bread enhanced with polyphenols and related antioxidants derived from a natural aqueous extract from green-fleshed kiwifruit (Actinidia deliciosa). Puree and four aqueous extracts, produced from ripe green kiwifruit in the absence of artificial preservatives, were subjected to storage stability trials at 4 degrees C, 20 degrees C and 38 degrees C, and were chemically characterized (phenolic, vitamin C and pectic polysaccharide contents). The aqueous extract with good stability and high phenolic and vitamin C contents was used for gluten-free bread-making. The resultant kiwifruit extract-enhanced bread was acceptable to a taste panel, possessing softer and smoother texture than plain gluten-free bread. Thus, the aqueous extract of kiwifruit puree containing health-beneficial constituents can be considered a functional ingredient for gluten-free bread formulation.

Effect of apple cell walls and their extracts on the activity of dietary antioxidants.

The effect of dietary fiber in the form of apple cell walls and pectin extracts on natural antioxidants was examined. Cell walls (CW), isolated from apples ( Malus domestica Borkh. cv. "Pacific Rose"), were incubated with ascorbic acid (AA) or quercetin in N-2-hydroxyethylpiperazine- N'-2-ethanesulfonic acid (HEPES) buffer (pH 6.5) at 37 degrees C for 2 h. The resulting supernatants were characterized by a ferric reducing antioxidant power (FRAP) assay and cyclic voltammetry (CV). The experiments were repeated with pectin isolated from the apple cell walls and commercial pectins and showed that polysaccharide preparations stabilized AA effectively but offered little protection against quercetin oxidation. The water-soluble components from cell walls appeared to be responsible for the observed effects of cell-wall polysaccharide preparations on antioxidant activity.