Defining the sensory profiles of raw almond (Prunus dulcis) varieties and the contribution of key chemical compounds and physical properties.
This study describes the sensory composition of commercial sweet almond varieties across two California growing seasons. It also discusses the relationship between sensory attributes and chemical and physical measures. Raw, whole almonds (43 samples each of 13 varieties in 2015 and 40 samples each of 10 varieties in 2016) were evaluated for their sensory profiles using descriptive sensory analysis. The 2016 samples were also analyzed for macro- and micronutrients, amygdalin, volatile composition (using gas chromatography-mass spectrometry), and physical properties, and the results were modeled with the sensory data. Independence, Sonora, and Wood Colony were harder, more fracturable, and crunchy, whereas Fritz and Monterey were more moist and chewy, reflecting their moisture contents. Aldrich and Fritz were higher in marzipan/benzaldehyde flavor, which is related to amygdalin, benzaldehyde, phenylethyl alcohol, and benzyl alcohol. New insights are provided into sweet-almond composition and the sensorial contribution of headspace volatiles. This assists almond growers and processors in describing and marketing almond varieties.
Relationships of Water Activity and Moisture Content to the Thermal Inactivation Kinetics of Salmonella in Low-Moisture Foods.
The enhanced thermal resistance of Salmonella in low-moisture foods (LMFs) presents a challenge when validating pathogen control processes. Product water is recognized as a controlling factor in thermal inactivation of Salmonella in or on LMFs, such as almonds. Water activity (aw) describes the state of water in a product; however, aw is temperature dependent and characterized by hysteresis between sorption states. Moisture content (%MC) describes the amount of water in a product; it is not temperature dependent and might be a more convenient metric than aw to account for water in thermal inactivation processes. To test these two metrics independently, Salmonella-inoculated almonds were equilibrated to two %MC levels but the same aw and to two aw levels but the same %MC. Equilibrated products were vacuum packaged and thermally treated in a water bath at 80°C. Survivors were recovered and enumerated. The resulting inactivation curves were used to fit the log-linear inactivation model, and the inactivation kinetics were compared. D-values ranged from 15.7 to 18.0 min, and the root mean square error was 0.25 to 0.69 log CFU/g. No differentiated (P > 0.05) effect attributable preferentially to aw or %MC was seen in the inactivation kinetics. The separate effects of aw and %MC on the inactivation kinetics of Salmonella in LMFs remain inconclusive, but analyses of data from prior studies strongly suggested an effect of sorption state. Further analysis is needed to identify which metric is best for modeling and validating thermal inactivation processes.
Selected nutrients and anti‐nutrients in peanut cultivars harvested in Brazil.
BACKGROUND: There are more than 30 peanut cultivars registered in Brazil. However, there is no published data about the content of nutrients and anti-nutrients even in the most commercially important ones. Therefore, our objective was to characterize commercial peanut cultivars harvested in Brazil by determining proximate and fatty acid compositions and contents of selected minerals and phytates, saponins and condensed tannins. RESULTS: Significant variations were found among the cultivars for almost all studied nutrients, except Mg. Granoleico and IAC 505 were identified as high oleic. Results were compared with data from the Brazilian Food Composition Table (TACO) and for this, percentage differences (D%) were calculated. Appreciable D% were found for proteins, lipids, ash, dietary fiber, almost all fatty acids (except 20:0), and almost all studied minerals (except zinc). Moreover, remarkable variations on contents of anti-nutrients were observed. IAC Red Tatu had the highest contents of saponins; IAC OL3 and IAC 886 had the highest amounts of phytates; and IAC 886 had the highest amounts of condensed tannins. CONCLUSION: Results confirm the relevance of differentiating cultivars in the market and in national food composition tables and databases. Furthermore, some of these cultivars may be indicated for new use trends.
Comparison of recovery and immunochemical detection of peanut proteins from differentially roasted peanut flour using ELISA.
The effect of heat on extractability and immunoreactivity of proteins from roasted peanut flours and whole peanuts was evaluated using two general protein assays and six commercial peanut ELISA kits, respectively. The highest amount of protein was recovered from roasted peanuts with all ELISAs, while recovery showed a decrease with increasing levels of roasting of the peanut flours. Only the Morinaga kit showed sufficient sensitivity to detect peanut at low concentrations of the dark roast peanut flours. Both the protein and immunoassays indicated a decrease in protein solubility with roasting. The underestimation by immunoassays is a combination of decreased solubility and heat induced changes in the proteins that are being targeted by the ELISA antibodies. These findings suggest that most commercial ELISA kits may not reliably quantify peanut present in dark roast peanut flours at ≤25 ppm.
Timing of Food Introduction and the Risk of Food Allergy.
Given that the prevalence of pediatric IgE-mediated food allergies (FA) has followed a substantive increase in recent decades, nowadays, a research challenge is to establish whether the weaning strategy can have a role in FA prevention. In recent decades, several studies have demonstrated that delayed exposure to allergenic foods did not reduce the risk of FA, leading to the publication of recent guidelines which recommend against delaying the introduction of solid foods after 4-6 months of age, both in high- and low-risk infants, in order to prevent food allergy. In the present review, focusing on cow's milk protein, hen's eggs, peanuts, soy, wheat and fish, we describe the current scientific evidence on the relationship between timing of these foods' introduction in infants' diet and allergy development.
Clinical Factors Associated with Peanut Allergy in a High Risk Infant Cohort.
BACKGROUND: Prognostication of peanut allergy (PNA) is relevant for early interventions. We aimed to determine baseline parameters associated with development of PNA in 3-15 month olds with likely egg and/or milk allergy, and/or moderate-severe atopic dermatitis (AD) and a positive egg/milk skin prick test (SPT), but no known PNA. METHODS: The primary endpoint was PNA [confirmed/convincing diagnosis or last classified as serologic PNA (<2 yrs, ≥5 kUA/L, otherwise ≥14 kUA/L, peanut-IgE)] among 511 participants (median follow-up, 7.3 years). Associations were explored with univariate logistic regression; factors with p<0.15 were analyzed by stepwise multiple logistic regression, using data stratified by PNA status and randomly assigned to development and validation datasets. RESULTS: 205/511 (40.1%) had PNA. Univariate factors associated with PNA (p<0.01) included: increased AD severity, larger egg and peanut SPT, greater egg, milk, peanut, Ara h1-h3 IgE, higher peanut IgG and IgG4, and increased pregnancy peanut consumption. P-values were between 0.01 and 0.05 for younger age, non-white race, lack of breastfeeding, and increased lactation peanut consumption. Using a development dataset, the multivariate model identified younger age at enrollment, greater peanut and Ara h2 IgE, and lack of breastfeeding as prognosticators. The final model predicted 79% in the development and 75% in the validation dataset (AUC=0.83 for both). Models using stricter or less strict PNA criteria both found Ara h2 as predictive. CONCLUSIONS: Key factors associated with PNA in this high risk population included lack of breastfeeding, age, and greater Ara h2 and peanut-specific IgE, which can be used to prognosticate outcomes.
Current management and use of oral immunotherapy in the United States for patients with peanut allergy.
BACKGROUND: Peanut allergy is a major health burden in the United States. Treatment is limited to avoidance and acutereaction management. No drug or medical product is approved for use as a peanut oral immunotherapy (POIT) agent. OBJECTIVE: To examine peanut allergy diagnosis and treatment, peanut challenge protocols, nonpublished POIT approaches, POIT practice requirements and logistical considerations, and barriers to providing POIT. METHODS: Qualitative in-depth telephonic interviews were conducted with 34 allergists and nurse food allergy specialistsacross the United States between April and June 2016. Interviewed clinicians managed > 100 patients with peanut allergy per year; 50% of the interviewed allergists offered POIT in clinical studies or used self-developed approaches. RESULTS: The physicians consistently reported conducting food challenges in 5-10% of patients to confirm a peanut allergydiagnosis. The allergists who offered POIT described using a variety of approaches. Areas of divergence included patientselection (ages, 4-7 years), peanut material (crushed peanuts, peanut flour, peanut protein, peanut butter, peanut extract),starting and ending doses, and updosing intervals (1 to 2 weeks). Generally, POIT administration and observation occupiedan examination room for up to 2 hours; some practices reported accommodating 2 to 5 patients who received POIT simultaneously. Among physicians who did not offer POIT, barriers included medicolegal risks and the lack of a U.S. Food and Drug Administration (FDA) approved therapy. CONCLUSION: Although POIT is currently not supported in treatment guidelines, some allergists have developed experimental POIT approaches to support patient needs. In the absence of a product that has approval by the FDA, EuropeanMedicines Agency (EMA) or other national competent authority, substantial variability in POIT approaches exists. Althoughlogistical factors are not major obstacles to adoption, POIT dose preparation can be perceived as burdensome, and observationrequires a dedicated staff. All the physicians interviewed suggested a need for effective, FDA-approved, disease-modifyingtreatments.
Food allergy endotype with high risk of severe anaphylaxis in children-Monosensitization to cashew 2S albumin Ana o 3.
BACKGROUND: Food allergy in children can be life-threatening. Component-resolved diagnostics approach to food anaphylaxis is rarely assessed in children. The aim of the study was to identify the food allergen components as the triggers responsible for severe anaphylaxis, with regard to characteristics and associated risks, among children in a large, population-based setting. METHODS: Two hundred and seventy-one children who were hospitalized due to systemic allergic reaction (SAR) and food anaphylaxis were recruited. Medical history was assessed, and culprit allergen source and anaphylaxis severity grade were established. Specific IgE to 112 allergen components using multiplex ImmunoCAP ISAC immunoassay and specific IgE to hazelnut, Cor a 14, and cashew, Ana o 3, using singleplex ImmunoCAP immunoassay were determined. RESULTS: We analyzed data from 237 SAR/anaphylaxis in 237 children. Trigger at allergen component level was defined for every episode. The most common triggers of SAR/anaphylaxis were seeds (50.6%), among them, the storage proteins. Anaphylaxis triggered by Ana o 3, 2S albumin from cashews (aOR = 15.0; 95% CI: 3.27 to 73.47); Tri a 19 from wheat (aOR = 9.93; 95% CI: 1.73 to 56.97); and Cor a 9 from hazelnut (aOR = 6.53; 95% CI: 1.16 to 36.72) had the worst clinical presentation including cardiovascular and severe respiratory symptoms (grade IV-V vs I-III in Cox scale). Thirteen out of 237 (5.5%) SAR/anaphylaxis patients were triggered by Ana o 3. Almost 82% of patients with severe Ana o 3 anaphylaxis were sensitized only to this component and had no concomitant food sensitization. CONCLUSION: Monosensitization to Ana o 3 is, irrespective of other parameters, connected with high risk of severe anaphylaxis.
Real-time PCR Detection Methods for Food Allergens (Wheat, Buckwheat, and Peanuts) Using Reference Plasmids.
Specific and sensitive real-time qualitative polymerase chain reaction (PCR) methods for the detection of food allergens including wheat, buckwheat, and peanuts were developed that could cancel between instrument effects and avoid risks of false-positives and false-negatives. In these real-time PCR analysis, the cutoff for determination of positive samples was set in every PCR run by using reference plasmids containing known copies of the target sequences. The copy numbers of the plasmids were used to detect the allergenic ingredients corresponding to 10 ppm (w/w) protein in highly processed foods (cooked for more than 30 min at 122 °C). Reference plasmid analysis for each real-time PCR run helped to minimize variability between runs and instruments (7900HT Real-Time PCR systems and Light Cycler Nano). It also helped to avoid false positives due to trace levels of contaminants from the laboratory environment or agricultural products. The specificity of the real-time PCR method was verified using 79 commonly used food materials and some of their relatives. The method was sensitive enough to detect those allergenic ingredients corresponding to 10 ppm (w/w) in seven types of incurred samples. The current official Japanese method was not able to detect the allergens in some of the incurred samples. The developed method can avoid false negatives due to lack of sensitivity and is useful to confirm positive ELISA screening tests.
Oral immunotherapy for peanut allergy (PACE): a systematic review and meta-analysis of efficacy and safety.
BACKGROUND: Oral immunotherapy is an emerging experimental treatment for peanut allergy, but its benefits and harms are unclear. We systematically reviewed the efficacy and safety of oral immunotherapy versus allergen avoidance or placebo (no oral immunotherapy) for peanut allergy. METHODS: In the Peanut Allergen immunotherapy, Clarifying the Evidence (PACE) systematic review and meta-analysis, we searched MEDLINE, EMBASE, Cochrane Controlled Register of Trials, Latin American & Caribbean Health Sciences Literature, China National Knowledge Infrastructure, WHO's Clinical Trials Registry Platform, US Food and Drug Administration, and European Medicines Agency databases from inception to Dec 6, 2018, for randomised controlled trials comparing oral immunotherapy versus no oral immunotherapy for peanut allergy, without language restrictions. We screened studies, extracted data, and assessed risk of bias independently in duplicate. Main outcomes included anaphylaxis, allergic or adverse reactions, epinephrine use, and quality of life, meta-analysed by random effects. We assessed certainty (quality) of evidence by the GRADE approach. This study is registered with PROSPERO, number CRD42019117930. RESULTS: 12 trials (n=1041; median age across trials 8·7 years [IQR 5·9-11·2]) showed that oral immunotherapy versus no oral immunotherapy increased anaphylaxis risk (risk ratio [RR] 3·12 [95% CI 1·76-5·55], I2=0%, risk difference [RD] 15·1%, high-certainty), anaphylaxis frequency (incidence rate ratio [IRR] 2·72 [1·57-4·72], I2=0%, RD 12·2%, high-certainty), and epinephrine use (RR 2·21 [1·27-3·83], I2=0%, RD 4·5%, high-certainty) similarly during build-up and maintenance (pinteraction=0·92). Oral immunotherapy increased serious adverse events (RR 1·92 [1·00-3·66], I2=0%, RD 5·7%, moderate-certainty), and non-anaphylactic reactions (vomiting: RR 1·79 [95%CI 1·35-2·38], I2=0%, high-certainty; angioedema: 2·25 [1·13-4·47], I2=0%, high-certainty; upper tract respiratory reactions: 1·36 [1·02-1·81], I2=0%, moderate-certainty; lower tract respiratory reactions: 1·55 [0·96-2·50], I2=28%, moderate-certainty). Passing a supervised challenge, a surrogate for preventing out-of-clinic reactions, was more likely with oral immunotherapy (RR 12·42 [95% CI 6·82-22·61], I2=0%, RD 36·5%, high-certainty). Quality of life was not different between groups (combined parents and self report RR 1·21 [0·87-1·69], I2=0%, RD 0·03%, low-certainty). Findings were robust to IRR, trial sequential, subgroup, and sensitivity analyses. INTERPRETATION: In patients with peanut allergy, high-certainty evidence shows that available peanut oral immunotherapy regimens considerably increase allergic and anaphylactic reactions over avoidance or placebo, despite effectively inducing desensitisation. Safer peanut allergy treatment approaches and rigorous randomised controlled trials that evaluate patient-important outcomes are needed.