Relationship between pulp structure breakdown and nutritional value of papaya (Carica papaya) and strawberry (Fragaria x ananassa) nectars using alternative thermal and non-thermal processing techniques.

BACKGROUND: Papaya and strawberry contain a wide array of nutrients that contribute to human health; however, availability of these fruits is limited due to their short shelf lives and seasonal nature. In this study, the effect of alternative techniques including ultra high temperature (UHT, 20-135 °C, 1-3 s) and irradiation (0-10 kGy) on carotenoid concentration, antioxidant capacity and changes to pulp structure using transmission electron microscopy were determined for papaya and strawberry nectars. RESULTS: UHT had moderate effects on antioxidant capacity, but the greatest overall release of carotenoids from the pulp matrix (34.2%, 6.26%, 8.31%; ß-cryptoxanthin, ß-carotene, and lycopene, respectively). Irradiation resulted in the greatest increase in antioxidant capacity [19.22 to 24.32 µmol Trolox equivalents kg(-1) (papaya), 190.51 to 287.68 µmol Trolox equivalents kg(-1) (strawberry)], with moderate effects on carotenoid concentration. CONCLUSION: This research demonstrates that decreases in nutrient value and antioxidant capacity can result from processing, but that regeneration of these losses can be seen corresponding to the apparent breakdown of pulp structure. © 2015 Society of Chemical Industry.

Developmental bisphenol A (BPA) exposure leads to sex-specific modification of hepatic gene expression and epigenome at birth that may exacerbate high-fat diet-induced hepatic steatosis.

Developmental bisphenol A (BPA) exposure increases adulthood hepatic steatosis with reduced mitochondrial function. To investigate the potential epigenetic mechanisms behind developmental BPA-induced hepatic steatosis, pregnant Sprague-Dawley rats were dosed with vehicle (oil) or BPA (100µg/kg/day) from gestational day 6 until postnatal day (PND) 21. After weaning, offspring were either challenged with a high-fat (HF; 45% fat) or remained on a control (C) diet until PND110. From PND60 to 90, both BPA and HF diet increased the fat/lean ratio in males only, and the combination of BPA and HF diet appeared to cause the highest ratio. On PND110, Oil-HF, BPA-C, and BPA-HF males had higher hepatic lipid accumulation than Oil-C, with microvesicular steatosis being marked in the BPA-HF group. Furthermore, on PND1, BPA increased and modified hepatic triglyceride (TG) and free fatty acid (FFA) compositions in males only. In PND1 males, BPA increased hepatic expression of FFA uptake gene Fat/Cd36, and decreased the expression of TG synthesis- and ß-oxidation-related genes (Dgat, Agpat6, Cebpα, Cebpß, Pck1, Acox1, Cpt1a, Cybb). BPA altered DNA methylation and histone marks (H3Ac, H4Ac, H3Me2K4, H3Me3K36), and decreased the binding of several transcription factors (Pol II, C/EBPß, SREBP1) within the male Cpt1a gene, the key ß-oxidation enzyme. In PND1 females, BPA only increased the expression of genes involved in FFA uptake and TG synthesis (Lpl, Fasn, and Dgat). These data suggest that developmental BPA exposure alters and reprograms hepatic ß-oxidation capacity in males, potentially through the epigenetic regulation of genes, and further alters the response to a HF diet.

Development of a point-of-use fortification technology for delivery of micronutrients in Honduras.

BACKGROUND: Micronutrient deficiencies continue to afflict children rural populations around the world. A micronutrient delivery vehicle (MDV) was developed as a point-of-use technology for fortification of meals for school-age children beneficiaries of the Healthy Schools Program (HSP) in Honduras. RESULTS: MDV combines micronutrient powder through a traditional dough-making process, using staple flours (wheat and nixtamalized corn), oil and water as ingredients. After mixing the ingredients and kneading, dough is extruded through a specially designed hand press into noodles. After drying (overnight, 23°C), noodles are broken into small pieces, mixed (1:100 w/w) with rice and cooked as customary. Dispersion studies with NaFeEDTA showed adequate distribution (<10% RSD) and recovery (>90%) in white rice. Color changes in MDV due to addition of vitamin A and iron (NaFeEDTA) carried forward into cooked rice. In Honduras, children from two rural schools (N = 47, 6-12 years) were not able to differentiate (triangle test) between control and unfortified MDV mixed (1:100 w/w) with white rice. Children from four schools (N = 83, 7-12 years) accepted control and iron fortified rice (3 mg Fe per serving) based on color and flavor similarly. CONCLUSION: This is a feasible point-of-use fortification technology for improvement of meals provided by the HSP in Honduras.

Identification of Important Aroma Components and Sensory Profiles of Minimally Processed (Unroasted) and Conventionally Roasted Dark Chocolates.

Roasting is an important unit operation for the development of characteristic chocolate aroma during manufacturing. However, there is an increase in interest in minimally processed chocolate products due to their potential positive health benefits. The odor-important compounds and sensory characteristics of minimally processed (unroasted) and conventionally roasted dark chocolates were determined by gas chromatography-olfactometry, aroma extract dilution analysis (AEDA), and stable isotope dilution analysis (SIDA). Except for acetic acid, all odorants had higher odor-activity values (OAVs) in roasted chocolate. Acetic acid, developed during fermentation and drying, had the highest OAV in both chocolates but was better preserved in unroasted chocolate. Compounds making a greater aroma impact on roasted chocolate compared with unroasted chocolate included dimethyl trisulfide, 2-ethyl-3,5-dimethylpyrazine, and 3-methylbutanal. Nine significant sensory attributes in unroasted and roasted chocolates were identified. Vinegar (aroma) and roasted (aroma and aroma by mouth), sweet (taste), and hardness (texture) attributes differed between unroasted and roasted chocolates. The results of this study enforce the embracement of low thermal processes to showcase the inherent flavor potential of cacao beans but also to support the concept of chocolate "terroir" by potentially preserving important aroma compounds developed during fermentation.

Drivers of cadmium accumulation in Theobroma cacao L. beans: A quantitative synthesis of soil-plant relationships across the Cacao Belt.

Elevated cadmium (Cd) concentrations in cacao and cocoa-based products (e.g., chocolate) present a potentially serious human health risk. While recent regulatory changes have established a threshold of 0.8 mg kg-1 for Cd content of cocoa-based products, the biophysical factors (e.g., climatic or edaphic conditions) that determine the amount of soil-derived Cd in the cacao bean are poorly understood and have yet to be quantitatively assessed across diverse production contexts. To determine the primary drivers of cacao bean Cd, we used the scientific literature to systematically compile a database of climatic, edaphic, and plant data from across the Cacao Belt, which is approximately 20 degrees latitude on either side of the equator. From this compiled dataset, we then used boosted regression trees to quantitatively synthesize and evaluate these drivers of cacao bean Cd. Total soil Cd concentration, soil pH, and leaf Cd were the best predictors of bean Cd content. Notably, we found that both available soil Cd and soil organic carbon (SOC) content had negligible effects on bean Cd. However, soil pH and SOC decreased the degree of bioconcentration of total soil Cd in the bean Cd concentration. Thus, given the difficulty in remediating soil Cd enriched soils, our results suggest that Cd mitigation strategies targeting plant physiology-based approaches (e.g., breeding, rootstocks) have a higher probability of success than soil-based strategies (e.g., remediation).

Microbes associated with spontaneous cacao fermentations - A systematic review and meta-analysis.

Chocolate is a product of the fermentation of cacao beans. Performed on-farm or at local cooperatives, these are spontaneous cacao fermentations (SCFs). To better understand SCFs, this study sought to identify SCF microbes, their interrelationships, and other key parameters that influence fermentation. This is important because differences in fermentation can have an impact on final product quality. In this study, a systematic data extraction was performed, searching for literature that identified microbes from SCFs. Each unique microbe, whether by location or by fermentation material, was extracted from the articles, along with parameters associated with fermentation. Data were collected and analyzed for three interactions: microbe-to-geography, microbe-to-fermentation method, and microbe-to-microbe. The goal was to attribute microbes to geographical locations, fermentation materials, or to other microbes. Statistically significant relationships will reveal target areas for future research. Over 1700 microbes (440 unique species) were identified across 60 articles. The top three countries represented are Brazil (22 articles, n = 612 microbes), the Ivory Coast (14 articles, n = 237), and Ghana (10 articles, n = 257). Several countries were far less, or never represented, and should be considered for future research. No specific relationship was identified with microbes to either geographical location or fermentation method. Using a Presence-Absence chart, 127 microbe-to-microbe interactions were identified as statistically significant. Data extraction into SCF research has revealed major gaps of knowledge for the cacao microbiome. By better understanding the cacao microbiome, researchers will be able to identify key microbes and fermentation parameters to better influence the fermentation.

Thermally Abused Frying Oil Potentiates Metastasis to Lung in a Murine Model of Late-Stage Breast Cancer.

Deep-frying is a popular form of food preparation used globally and throughout in the United States. Each time dietary oils are heated to deep-frying temperatures, they undergo chemical alterations that result in a new matrix of lipid structures. These lipid products include triglyceride dimers, polymers, oxidized triglycerides, and cyclic monomers, which raises nutritional concerns about associations between these lipid products and heightened health risks. Reports of associations between thermally abused frying oil and deleterious health outcomes currently exist, yet there is little information concerning the effects of thermally abused frying oil consumption and the progression of breast cancer. This study used a late-stage breast cancer murine model and in vivo bioluminescent imaging to monitor progression of metastasis of 4T1 tumor cells in animals consuming fresh soybean oil (SBO) and a thermally abused frying oil (TAFO). Bioluminescent and histologic examinations demonstrated that TAFO consumption resulted in a marked increase of metastatic lung tumor formation compared to SBO consumption. Further, in animals consuming the TAFO treatment diet, metastatic tumors in the lung displayed a 1.4-fold increase in the Ki-67 marker of cellular proliferation and RNA-sequencing analysis of the hepatic tissue revealed a dietary-induced modulation of gene expression in the liver.

Microencapsulation of docosahexaenoic acid (DHA) with four wall materials including pea protein-modified starch complex.

Omega-3 fatty acids, specifically docosahexaenoic acid (DHA, 22 carbons and 6 double bonds) are fundamental compounds for a healthy diet. However, due to their unsaturated nature, omega fatty acid-rich oils are chemically unstable and susceptible to oxidative deterioration. The oxidation results in production of free radicals and unpleasant tastes, negatively impacting the shelf-life, sensory properties, and acceptability of food products. This study was conducted to examine the effect of wall materials on protection of DHA in canola oil against oxidation. A total of 4 wall materials including pea protein isolate (PPI), pea protein isolate - modified starch complex (PPI-MS), Tween 20, and SDS were used for microemulsion preparation with canola oil containing DHA. The freeze-dried powders were analyzed with respect to physicochemical characteristics, oxidative stability, and release properties. The results showed that the PPI-MS as a natural polymeric wall material exhibited similar or better encapsulation efficiency and acceptable level of peroxide value compared to the synthetic surfactants (Tween 20 and SDS). The utilization of protein-polysaccharide complexes enabled the incorporation of specific properties of each biopolymer to further improve emulsion stability for the production of capsules with improved oxidative stability.

Iron Fortification of Spiced Vinegar in the Philippines.

Despite existent fortification initiatives in the Philippines, approximately 50% of the population still suffers from iron deficiency anemia (IDA), mainly in rural areas. Fortification of staple foods has been proved successful in China and Vietnam. Coconut spiced vinegar (SV) is an inexpensive, widely available, and culturally acceptable condiment in Filipino households; however, no technical evidence exists on its potential as fortification vehicle. This study aimed to physicochemically characterize and evaluate the consumer acceptability of SV fortified with ferrous sulfate (FS), ferrous fumarate (FF), or sodium iron ethylenediaminetetraacetate (NaFeEDTA) at 0.2 mg Fe/mL. Iron fortificants were added directly to SV, vortexed, and stored for analysis. A nonfortified SV served as a control. Physicochemical analyses (pH, titratable acidity, color, turbidity, and iron recovery) were conducted from 0 to 6 months postfortification. Consumer acceptability (9-point hedonic scale: color, appearance, aroma, sourness, and overall acceptability) was conducted using 1-month fortified vinegar in 96 students and 27 women. Iron recovery of fortified samples was high and similar (>97%) after 3 days of fortification and remained >87% at 6 months postfortification. All samples had minimum acidity of 5.31% and pH between 3.12 and 3.3. Color difference against the control followed the next order: SV-NaFeEDTA < SV-FS = SV-FF. Among students, acceptability of SV-FS and SV-FF were lower than the control and SV-NaFeEDTA for all attributes (P < 0.05) except aroma. In women, overall acceptability and aroma were not different among samples (P > 0.05). Overall, SV-NaFeEDTA had similar acceptability to the control, and was the most accepted fortified vinegar. SV-NaFeEDTA shows potential (in terms of physicochemical stability and consumer acceptability) to be used as an iron-delivery vehicle to address IDA. PRACTICAL APPLICATION: The present study addresses the technical and organoleptic challenges of fortifying Filipino spiced vinegar with three iron sources. About 50% of the Filipino population (especially women and children) still suffers from iron deficiency, thus, more effective ways to deliver iron are needed. If successful, our study could pose as the base milestone for implementing mass iron fortification of spiced vinegar, given its frequent consumption and reach of all socioeconomic pockets of the Filipino population. Our aim is to improve the overall nutritional health of at-risk populations, and our study is one step closer to achieve this goal.

Antioxidant capacity and phenolic content of grapes, sun-dried raisins, and golden raisins and their effect on ex vivo serum antioxidant capacity.

Grapes and raisins provide phenolic antioxidants, which contribute to their potential health benefits. The objectives of this study were to compare the antioxidant capacity and phenolic content of green Thompson seedless grapes (the most common variety of grapes consumed in the United States), sun-dried raisins, and golden raisins (both produced from Thompson seedless grapes) and to observe the effects of their consumption over 4 weeks in 15 healthy human males with a cross-over design. The oxygen radical absorbance capacity (ORAC) (positive statistical significance for grapes after 2 weeks and golden raisins after 3 weeks), serum oxidation (positive statistical significance for golden raisin lag time after 4 weeks), total phenolics (no significant effects), and C-reactive protein (no significant effects) were monitored. Immediately postconsumption, there were some significant nonpositive changes. It is hypothesized that these negative results may be explained by postprandial oxidation, a known effect after carbohydrate consumption. Golden raisins had the highest antioxidant capacity and phenolic content. The consumption of a serving of grapes or raisins each day, in addition to a typical diet, may not be sufficient to overcome postprandial oxidation when consumed with other high carbohydrate foods but may have beneficial antioxidant effects over time.

Functionalizing soy protein nano-aggregates with pH-shifting and mano-thermo-sonication.

Plant protein-mediated nano-delivery systems have gained increasing attention in the food and pharmaceutical industries in recent years. Several physical and chemical methods for improving the functional properties of plant proteins with respect to the native forms have been proposed. This study presents a new approach, which combines pH-shifting and mano-thermo-sonication (MTS) to produce soy protein nano-aggregates with significantly improved functional properties. Soy-protein isolate (SPI) was treated with pH-shifting at pH 12 or in combination with MTS and high-pressure homogenization (HPH). Response Surface Methodology was used to find the optimal conditions (50°C, 200kPa, and 60s) for the MTS. The combination of pH-shifting and MTS resulted in spherical SPI aggregates of the smallest size, 27.1±1nm, as shown by transmission electron microscopy. The SPI nanoaggregates were used to prepare oil-in-water nanoemulsions with canola oil, which exhibited good stability over 21days at 4°C. In addition, the pH 12-MTS samples had resulted in the highest protein solubility, lowest turbidity, free sulfhydryl and disulfide bonds, surface hydrophobicity, antioxidant activity, and rheological and emulsifying properties than the other samples.

Development and Physico-Chemical Characterization of a Shea Butter-Containing Lipid Nutrition Supplement for Sub-Saharan Africa.

Lipid-based nutrient supplements (LNS) are used to prevent and treat moderate and severe acute malnutrition, a leading cause of mortality in children-under-five. The physical and chemical changes of two new LNS products were evaluated before and after accelerated shelf life testing (ASLT) according to protocols suggested by the U.S. Agency for International Development (USAID) and Doctors without Borders and compared against USAID's A-20 paste as a control. LNS formulas containing Shea butter from the Shea nut tree (Vitellaria paradoxa), a common fat source in parts of Sub-Saharan Africa, with and without flax-seed oil, as a source of omega-3 fatty acids, were developed. LNS formulas were batched (0.8 kg) in a wet grinder, sealed under nitrogen in three-layer mini-pouches (20 g), and underwent ASLT at 40 ± 2 °C for six months with sampling every eight weeks. At each time point, water activity, moisture, peroxide value, oil separation, vitamin C content, and hardness were evaluated. Results showed comparable stability among all formulas with an increase in Aw (p < 0.05) but no change in vitamin C, oil separation, or peroxide value. Addition of Shea butter improved the LNS's hardness, which remained stable over time. Modifying fat profile in LNS can improve its texture and essential fatty acid content without affecting its storage stability.

Omega-3-Fortified Lipid-Based Nutrient Supplement: Development, Characterization, and Consumer Acceptability.

BACKGROUND: Incorporation of omega-3 polyunsaturated fatty acid (PUFA) sources to lipid-based nutrition supplement (LNS) formulations for undernourished populations presents a challenge due to reduced shelf life and poor consumer acceptability. OBJECTIVE: To systematically develop an omega-3-fortified LNS formulation, using flaxseed oil (FO), by optimizing its processing stability and evaluating its sensory acceptance. METHODS: LNS formulations were formulated to yield approximately 452 kcal, 13.2 g of protein, 30 g of fat, and 53 g of carbohydrates per 100 g. Response surface methodology (RSM) with 4-factor-3-level: omega-3 fatty acid source (FO; 0%-10%), antioxidant (ascorbyl palmitate: 0.0%-0.03%), emulsifier (soy lecithin: 0.5%-1.5%), and storage time (0-6 months at 40°C) was used to optimize LNS's functionality and storage stability. Factor effects were evaluated for peroxide value, oil separation, water activity, moisture content, hardness, and vitamin C content of the samples. Consumer acceptability was assessed using a 9-point hedonic scale. RESULTS: After 6 months of accelerated storage, the addition of FO to LNS formula resulted in increased peroxide values (7.75 mEq/kg fat) and lipid separation and a reduction in vitamin C and water activity. Optimal levels to maximize storage time and FO and minimize oxidation were 0.02% antioxidant, 1.5% emulsifier, and 4.9% FO. Indian women and students accepted LNS formulations with or without FO similar to other commercial supplements. CONCLUSION: An LNS containing FO with improved omega-6/omega-3 PUFA ratio was successfully formulated with staple Indian ingredients and optimized for storage stability using RSM.

Synergistic potential of papaya and strawberry nectar blends focused on specific nutrients and antioxidants using alternative thermal and non-thermal processing techniques.

Traditional processing has detrimental effects on nutrient value of fruit nectars; however, combining fruit nectars prior to processing can result in synergistic outcomes, e.g., a combination of nutrients providing a greater effect than they would individually, thus offsetting these losses. To examine this food synergism, papaya and strawberry nectars and their respective blends (25P:75S, 50P:50S, 75P:25S) were processed using ultra high temperature (UHT) and irradiation and examined for ascorbic acid concentration, carotenoid concentration, and antioxidant capacity. Ascorbic acid concentration was best retained after UHT processing, with synergistic relationships in all blends. Synergistic relationships were observed for ß-cryptoxanthin concentration after irradiation. ß-Carotene experienced both antagonistic and additive relationships whereas lycopene concentration encountered synergistic relationships in the 25P:75S blend for both techniques. All blends exhibited synergistic relationships for antioxidant capacity after UHT processing. These findings demonstrate the benefits of blending fruit nectars; producing a superior product than either fruit processed individually.

Bioactive amines in Passiflora are affected by species and fruit development.

Bioactive amines were determined in selected passion fruit species and throughout fruit development. The same amines (spermine, spermidine, agmatine, putrescine and tryptamine) were found in four Passiflora species (2008-2010 growing seasons) at different concentrations: P. alata had higher polyamines (spermine+spermidine, 8.41mg/100g); P. setacea and P. nitida had higher putrescine (>7.0mg/100g); and P. setacea had higher agmatine contents (1.37mg/100g) compared to the others. The indolamine tryptamine was present at low concentrations in all species (~0.05mg/100g). P. nitida and P. alata had the highest soluble solids (~18°Brix); P. edulis had the lowest pH (2.97) and P. nitida the highest pH (4.19). Throughout P. setacea fruit development, the concentrations of spermidine, putrescine and agmatine decreased; spermine contents did not change; and pH decreased. Fruit shelf life and some of the health promoting properties of Passiflora and their synthesis are modulated by species.

Delayed spatial alternation impairments in adult rats following dietary n-6 deficiency during development.

Dietary n-3 fatty acid (FA) deficiencies during development can cause learning and memory impairments, but the functional effects of dietary n-6 FA deficiencies, reflected in a lowered n-6/n-3 ratio, are less clear. We investigated the effects of maternal diets containing fish oils, resulting in lowered n-6/n-3 ratios, on a spatial working memory task in their offspring. Starting on gestational day 6, Sprague-Dawley timed-pregnant rats were placed on one of three experimental diets: control (unadulterated powdered rat chow), Pacific Ocean (PO) fish (powdered rat chow containing 20% (w/w) lyophilized PO salmon), or PO oil (powdered rat chow containing 6% (w/w) oil extracted from PO salmon). The 6% oil dose was selected because it is equivalent to the amount of oil in the 20% lyophilized fish diet. The experimental diets were fed until weaning on postnatal day (PND) 21, at which time all pups were placed on the rat chow diet. Starting on approximately PND77, one male and one female from each litter began a cognitive test battery using 2-lever operant chambers. PO groups failed to reach the same level of performance as the controls on the delayed spatial alternation (DSA) task and also showed decreased performance on delay trials. FA analyses of the diets found that the n-6/n-3 ratios for the PO fish and oil groups were reduced to 2.5 and 3.2, respectively, vs. 6.9 for controls. Analysis of brain tissue taken from pups on PND21 confirmed that the n-6/n-3 ratios within the brain were significantly reduced from 1.18 for controls to 0.87 and 0.90 for PO fish and oil groups, respectively. Specifically, the PO diets significantly increased long-chain n-3 FAs (20:5 n-3 and 22:6 n-3) and decreased long-chain n-6 FAs (20:4 n-6 and 22:4 n-6) in the brain. Thus, the observed delayed spatial alternation impairments in rats fed PO fish and fish oil are hypothesized to have resulted from the altered n-6/n-3 FA ratios.

Antioxidant capacity of honeys from various floral sources based on the determination of oxygen radical absorbance capacity and inhibition of in vitro lipoprotein oxidation in human serum samples.

Honeys from seven different floral sources were analyzed for in vitro antioxidant capacity and total phenolic content. Antioxidant capacity was measured by the oxygen radical absorbance capacity (ORAC) assay and by monitoring the formation of conjugated dienes as an index of the inhibition of copper-catalyzed serum lipoprotein oxidation. ORAC values ranged from 3.1 to 16.3 micromol Trolox equivalent/g honey. The darkest colored honeys, such as buckwheat honey, had the highest ORAC values. A linear correlation was observed between phenolic content and ORAC activity of the investigated honeys (p < 0.0001, R (2) = 0.9497). The relationship between the ORAC activity and inhibition of lipoprotein oxidation by the honeys yielded a correlation coefficient of 0.6653 (p = 0.0136). This work shows that honey may be used as a healthy alternative to sugar in many products and thereby serve as a source of dietary antioxidants.

Honey as a protective agent against lipid oxidation in ground turkey.

Lipid oxidation is a major deteriorative factor in meats. Sources of natural antioxidants that are as effective as commercially available antioxidants are desired. The objective of this research was to investigate honey as an inhibitor of lipid oxidation in ground poultry. The antioxidant content of different varieties of honey was investigated spectrophotometrically and honey's effectiveness in reducing oxidation of ground poultry determined by monitoring thiobarbituric acid reactive substances (TBARS). Buckwheat honey had the highest antioxidant content and acacia honey the lowest. Honeys of different floral sources differed in their protection against lipid oxidation. Buckwheat honey (5%, w/w) reduced TBARS approximately 70%, whereas acacia honey reduced TBARS approximately 34% at 3 days of storage at 4 degrees C. In comparison to butylated hydroxytoluene and tocopherol (0.02% of total fat), honey (at 5% of the weight of the meat) was much more effective at preventing oxidation. Honey has great potential as an antioxidant source and may result in greater acceptability of meat products and prevent negative health implications of oxidized meats.

Buckwheat honey increases serum antioxidant capacity in humans.

Honey has been known to exert significant in vitro antioxidant activity, in part due to its phenolic content. However, conclusions that the antioxidants in honey are or are not efficacious in the human body cannot be reached if its antioxidant action is not assessed as part of a human study. In the present study, the acute effect of consumption of 500 mL of water, water with buckwheat honey, black tea, black tea with sugar, or black tea with buckwheat honey on serum oxidative reactions was examined in 25 healthy men. Antioxidant capacity of human serum samples was measured using different methods: the oxygen radical absorbance capacity (ORAC) assay, ex vivo susceptibility of serum lipoprotein to Cu(2+)-induced oxidation, and the thiobarbituric acid reactive substances (TBARS) assay. The results showed that the serum antioxidant capacity determined by ORAC increased significantly (p < 0.05) by 7% following consumption of buckwheat honey in water. No significant changes in serum antioxidant capacity could be established after the consumption of any of the other beverages. Ex vivo serum lipoprotein oxidation and TBARS values were not significantly altered after consumption of any of the five beverages. This study provides primary evidence of the in vivo antioxidant activity of buckwheat honey. However, long-term studies and epidemiological data are necessary to investigate whether honey consumption can exert overall antioxidant-related health benefits.

Antimutagenic effect of various honeys and sugars against Trp-p-1.

Honey has been used since ancient times as a flavorful sweetener and for its therapeutic and medicinal effects. Consumers' demand for natural, healthy products has driven renewed interest in honey's health benefits. The commonly encountered food mutagen, Trp-p-1, has been demonstrated to be mutagenic in bacteria and carcinogenic in animals. Chemically, honey is quite complex. Honey is comprised primarily of sugars; however, it contains many other potentially biologically active components, such as antioxidants. Sugars have been reported to display both mutagenic and antimutagenic effects in different systems; antioxidants often display antimutagenic activity. Little information exists about potential antimutagenic effects of honey. Antimutagenicity of honeys from seven different floral sources against Trp-p-1 was tested via the Ames assay and compared to that of a sugar analogue and to individually tested simple sugars. All honeys exhibited significant inhibition of Trp-p-1 mutagenicity; most demonstrated a linear correlation between percentage inhibition and log transformed honey concentration from 10 microg/mL to 20 mg/mL. Each displayed significant degrees of inhibition of mutagenicity above concentrations of 1 mg/mL, with individual variations in degree of effectiveness. Buckwheat honey displayed the greatest inhibition at 1 mg/mL, with slightly less effectiveness at higher concentrations. A sugar analogue demonstrated a pattern of inhibition similar to that of the honeys, with enhanced antimutagenicity at concentrations greater than 1 mg/mL. Glucose and fructose were also similar to honeys and were more antimutagenic than maltose and sucrose.