Composition and properties of virgin pistachio oils and their by-products from different cultivars.
Pistachios (Pistacia vera) exhibit an interesting nutritional value, due to the high content of oleic acid and minor components with antioxidant and bioactive properties. This work aimed to characterize pistachio virgin oils and their partially defatted residual cakes, obtained from eight cultivars (Aegina, Avdat, Kastel, Kerman, Larnaka, Mateur, Napoletana, and Sirora). Interesting results on phenolics, tocopherols and antioxidant activity were observed, which were greatly affected by variety. Pistachio virgin oils are rich in healthy oleic acid (55-74%), phytosterols (3200-7600mg/kg) and γ-tocopherol (550-720mg/kg). A high content of phenolic compounds (8600-15000mg/kg gallic acid equivalents) and the corresponding antioxidant activities (12-46 and 155-496mmol/kg for DPPH and ORAC) of the residual cakes demonstrate their potential applications as functional ingredients and as rich sources of bioactive compounds. Moreover, virgin pistachio oils possess peculiar and pleasant sensory characteristics, contributing greater added value to the consumers compared to refined vegetable oils.
LC-MS profiling highlights hazelnut (Nocciola di Giffoni PGI) shells as a byproduct rich in antioxidant phenolics.
The Italian "Nocciola di Giffoni", also known as "Tonda di Giffoni", a labelled Protected Geographical Indication (PGI) product, represents an important economic resource for the Italian market. The methanol (MeOH) extract of "Tonda di Giffoni" shells has been investigated for the phenolic content, assayed by the Folin-Ciocalteu method, and for the antioxidant activity by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Trolox Equivalent Antioxidant Capacity (TEAC) assays. In order to achieve deeper insight into the chemical composition of the shells of hazelnut "Nocciola di Giffoni" and to highlight the occurrence of biologically active compounds, a phytochemical investigation was carried out. An initial Liquid Chromatography - Mass Spectrometry (LC-MS) profile of the methanol (MeOH) extract of the shells of C. avellana, cultivar "Tonda di Giffoni" led to the identification of sixteen compounds, of which the structures were elucidated by Nuclear Magnetic Resonance (NMR) spectroscopy. These were identified as a new diarylheptanoid, giffonin V (13), along with fifteen known phenolic compounds belonging to diarylheptanoid, neolignan, phenilpropanoid and flavonoid classes. In order to perform the quantitative determination of the main compounds of MeOH extract of C. avellana L. shells, an analytical method based on liquid chromatography coupled to mass spectrometry (LC-MS) with electrospray ionization source (ESI) and triple quadrupole mass analyzer (QqQ), using multiple reaction monitoring (MRM) scan mode, was developed and validated. The quantitative results highlight that main compounds occurred in the extract in concentration ranging from 6.4 to 83.3 (mg/100g). The antioxidant activity of all the isolated compounds evaluated by TEAC assay showed as the flavonoid derivatives exhibited a higher free-radical-scavenging activity. Moreover, the cytotoxicity of each compound was tested against the cancer cell lines A549 and Hela and against the human skin fibroblasts HaCat. None of tested compounds, in a range of concentrations between 12.5 and 100μM, cause a significant reduction of the cell number.
Effect of Drying Moisture Exposed Almonds on the Development of the Quality Defect Concealed Damage.
Concealed damage (CD), is a term used by the nut industry to describe a brown discoloration of kernel nutmeat that becomes visible after moderate heat treatments (e.g., roasting). CD can result in consumer rejection and product loss. Postharvest exposure of almonds to moisture (e.g., rain) is a key factor in the development of CD as it promotes hydrolysis of proteins, carbohydrates, and lipids. The effect of drying moisture-exposed almonds between 45 to 95 °C, prior to roasting was evaluated as a method for controlling CD in roasted almonds. Additionally, moisture-exposed almonds dried at 55 and 75 °C were stored under accelerated shelf life conditions (45 °C/80% RH) and evaluated for headspace volatiles. Results indicate that drying temperatures below 65 °C decreases brown discoloration of nutmeat up to 40% while drying temperatures above 75 °C produce significant increases in brown discoloration and volatiles related to lipid oxidation, and nonsignificant increases in Amadori compounds. Results also demonstrate that raw almonds exposed to moisture and dried at 55 °C prior to roasting, reduce the visual sign of CD and maintain headspace volatiles profiles similar to almonds without moisture damage during accelerated storage.
The effects of ‘activating’ almonds on consumer acceptance and gastrointestinal tolerance.
PURPOSE: Recommendations to soak nuts prior to consumption to reduce phytate concentrations and improve gastrointestinal tolerance have received much attention in the popular press. This is despite no supporting scientific evidence for the practice. There is also a lack of information about how soaking nuts might affect consumer acceptability. This study primarily assessed the effects of soaking almonds on consumer acceptance and secondly assessed effects on gastrointestinal tolerance. METHODS: In this 8-week randomised crossover trial, 76 participants were allocated in balanced order to receive 30 g/day of four different preparations of almonds for 12 days: whole unsoaked, whole soaked, sliced unsoaked, and sliced soaked. Ratings of overall liking, desire to consume, and likelihood of future consumption, and severity of gastrointestinal symptoms were measured daily on visual analogue scales. The phytate concentrations were measured in all four nut types using high-performance liquid chromatography. RESULTS: Mean acceptance ratings of all nut types were above the neutral point indicating they were acceptable. However, sliced soaked almonds were rated significantly lower overall for all three acceptance scales compared to the other treatments (all P ≤ 0.003). The sliced unsoaked almonds were rated lower than both whole nut treatments (all P ≤ 0.006), while there were no significant differences between the two whole nut treatments (all P ≥ 0.511). Gastrointestinal symptoms were minimal, but flatulence was rated significantly higher for all time points combined for soaked whole nuts compared to unsoaked whole nuts (P = 0.005). Compared to the whole unsoaked nuts (mean [SD] 531 [9] mg/100 g), phytate concentration was higher for the whole soaked almonds (563 [38] mg/100 g, P = 0.016), with no evidence of a difference for the sliced soaked almonds (548 [27] mg/100 g, P = 0.197) and no difference between the soaked forms (P = 0.262). CONCLUSIONS: This research supports previous results suggesting nuts, including different forms, are an acceptable food. They are also well tolerated gastrointestinally, but soaking does not improve gastrointestinal tolerance or acceptance as claimed in the lay literature.
Influence of genotype and crop year in the chemometrics of almond and pistachio oils.
BACKGROUND: Almond and pistachio oils can be considered as interesting products to produce and commercialize due to their health promoting properties. However, these properties are not consistent because of the differences that appear in oils as a result of the genotype and the crop year. The analysis of these variations and their origin is decisive to ensure the commercial future prospects of these nut oils. RESULTS: Although significant variability has been reported in almond and pistachio oils as a result of the crop year and the interaction between the crop year and the genotype, the genotype itself remains as the main factor determining oil chemometrics. Oils fatty acid profile has been mainly determined by the genotype, with the exception of palmitic fatty acid in pistachio oil. However, the crop year affects the concentration of some minor components of crucial nutritional interest as total polyphenols and phytosterols. CONCLUSION: Regarding reported differences in oil, some almond and pistachio genotypes should be prioritised for oil extraction. Breeding programmes focused on the improvement of specific characteristics of almond and pistachio oils should focus on chemical parameters mainly determined by the genotype.
Natural variation of selenium in Brazil nuts and soils from the Amazon region.
Brazil nut tree (Bertholletia excelsa) is native of the Amazon rainforest. Brazil nuts are consumed worldwide and are known as the richest food source of selenium (Se). Yet, the reasoning for such Se contents is not well stablished. We evaluated the variation in Se concentration of Brazil nuts from Brazilian Amazon basin, as well as soil properties, including total Se concentration, of the soils sampled directly underneath the trees crown, aiming to investigate which soil properties influence Se accumulation in the nuts. The median Se concentration in Brazil nuts varied from 2.07 mg kg-1 (in Mato Grosso state) to 68.15 mg kg-1 (in Amazonas state). Therefore, depending on its origin, a single Brazil nut could provide from 11% (in the Mato Grosso state) up to 288% (in the Amazonas state) of the daily Se requirement for an adult man (70 μg). The total Se concentration in the soil also varied considerably, ranging from <65.76 to 625.91 μg kg-1, with highest Se concentrations being observed in soil samples from the state of Amazonas. Se accumulation in Brazil nuts generally increased in soils with higher total Se content, but decreased under acidic conditions in the soil. This indicates that, besides total soil Se concentration, soil acidity plays a major role in Se uptake by Brazil nut trees, possibly due to the importance of this soil property to Se retention in the soil.
Detection of the Peanut Allergens Ara h 2 and Ara h 6 in Human Breast Milk: Development of 2 Sensitive and Specific Sandwich ELISA Assays.
BACKGROUND: Little is known about breast milk as a vehicle for tolerance development or sensitization to peanuts very early in life. Thus, well-characterized and highly sensitive detection systems for the reliable determination of peanut allergens in breast milk are mandatory. METHODS: For the quantification of the marker allergens Ara h 2 and Ara h 6 in the low nanogram per milliliter range in breast milk samples of a German cohort, sensitive and highly specific sandwich ELISAs were optimized and validated. RESULTS: The Ara h 2 ELISA revealed a limit of detection (LOD) of 1.3 ng Ara h 2/mL and a quantification range of 2.3-250 ng/mL, the Ara h 6 ELISA showed an LOD of 0.7 ng/mL and a working range of 1.1-14.4 ng/mL. The assays showed no relevant cross-reactivity against other potentially cross-reactive legume, seed, and tree nut extracts (<0.01%, except for Ara h 1 in the Ara h 2 ELISA <0.1%). Ara h 2 was detectable in breast milk samples from 14/40 (35%) of the participants in concentrations from 2.3 to 184 ng/mL, Ara h 6 appeared in 9/40 (22.5%) of the lactating mothers between 1.1 and 9.7 ng/mL, and 1 highly positive sample with 79 ng/mL. Both allergens appeared at the same time points, but Ara h 6 in lower concentrations than Ara h 2. CONCLUSIONS: Sensitive and specific diagnostic tools for the determination of Ara h 2 and Ara h 6 in human breast milk were established. The kinetics of secreted Ara h 2 and Ara h 6 seem to be similar but with a difference in concentration. Follow-up investigations on their tolerogenic or sensitizing properties in breast milk become now accessible.
Age-Based Causes and Clinical Characteristics of Immediate-Type Food Allergy in Korean Children.
PURPOSE: Age-based causes and clinical characteristics of immediate-type food allergy (FA) have not been sufficiently studied. Therefore, we investigated age-dependent clinical profiles of FA in Korean children through an extensive multicenter investigation. METHODS: Using a case report form developed by the authors, a retrospective medical record review was performed of patients (0-18 years old) diagnosed with immediate-type FA between September 2014 and August 2015 in 14 tertiary hospitals in Korea. RESULTS: A total of 1,353 children and adolescents, 93% younger than 7 years, were enrolled in the present study, and 1,661 cases of immediate-type FA were recorded in these patients. The 7 major causative foods were cow's milk (28.1%), hen's eggs (27.6%), wheat (7.9%), walnuts (7.3%), peanuts (5.3%), buckwheat (1.9%), and shrimps (1.9%). Categorizing the patients into 4 age groups revealed that the most common causative food was different for each age group: cow's milk (<2 years), walnuts (2-6 years), walnuts (7-12 years), and buckwheat (13-18 years). The onset time of symptoms was less than 10 minutes in 49%, between 10 and 30 minutes in 17%, and between 30 minutes and 2 hours in 34% of cases. Food-induced anaphylaxis was reported in 506 (30.5%) out of 1,661 cases, and the 7 major causes of food-induced anaphylaxis was cow's milk (27.5%), hen's eggs (21.9%), wheat (11.3%), walnuts (10.5%), peanuts (5.9%), buckwheat (4.2%), and pine nuts (3.0%). The proportion of anaphylaxis was highest in the patients allergic to buckwheat (67.7%), followed by those allergic to pine nuts (57.7%), walnuts (43.8%), wheat (43.5%), and peanuts (34.1%). CONCLUSIONS: The 5 major causative foods of immediate-type FA in Korean children were cow's milk, hen's eggs, wheat, walnuts, and peanuts. The distribution of causative foods was considerably distinctive according to different age groups. Anaphylaxis was reported in 30.5% of immediate-type FA cases.
CRD and beyond: multivariable regression models to predict severity of hazelnut allergy.
BACKGROUND: Component-resolved diagnosis (CRD) has revealed significant associations between IgE against individual allergens and severity of hazelnut allergy. Less attention has been given to combining them with clinical factors in predicting severity. AIM: To analyze associations between severity and sensitization patterns, patient characteristics and clinical history, and to develop models to improve predictive accuracy. METHODS: Patients reporting hazelnut allergy (n=423) from 12 European cities were tested for IgE against individual hazelnut allergens. Symptoms (reported and during DBPCFC) were categorized in mild, moderate and severe. Multiple regression models to predict severity were generated from clinical factors and sensitization patterns (CRD- and extract-based). Odds ratios (OR) and areas under receiver operating characteristic (ROC) curves (AUC) were used to evaluate their predictive value. RESULTS: Cor a 9 and 14 were positively (OR 10.5 and 10.1 respectively), and Cor a 1 negatively (OR 0.14) associated with severe symptoms during DBPCFC, with AUCs of 0.70-073. Combining Cor a 1 and 9 improved this to 0.76. A model using a combination of atopic dermatitis (risk), pollen allergy (protection), IgE against Cor a 14 (risk) and walnut (risk), increased the AUC to 0.91. At 92% sensitivity, the specificity was 76.3% and the positive and negative predictive values 62.2% and 95.7%, respectively. For reported symptoms, associations and generated models proved to be almost identical but weaker. CONCLUSION: A model combining CRD with clinical background and extract-based serology is superior to CRD alone in assessing the risk of severe reactions to hazelnut, particular in ruling out severe reactions.
Effects of industrial cashew nut processing on anacardic acid content and allergen recognition by IgE.
Cashew nuts are important both nutritionally and industrially, but can also cause food allergies in some individuals. The present study aimed to assess the effect(s) of industrial processing on anacardic acids and allergens present in cashew nuts. Sample analyses were performed using liquid chromatography coupled with mass spectrometry, SDS-PAGE and immunoassay. The anacardic acid concentration ranged from 6.2 to 82.6mg/g during processing, and this variation was attributed to cashew nut shell liquid incorporation during storage and humidification. Dehydrated and selected samples did not significantly differ in anacardic acid content, having values similar to the raw sample. SDS-PAGE and immunoassay analysis with rabbit polyclonal sera and human IgE indicated only minor differences in protein solubility and antibody binding following processing steps. The findings indicate that appreciable amounts of anacardic acid remain in processed nuts, and that changes to cashew allergens during industrial processing may only mildly affect antibody recognition.