Fermentation as a strategy to improve the bioactive and antioxidant properties of walnuts and their derived products
Oxidative stress is a significant factor in the development of many chronic illnesses, and antioxidants play a vital role in mitigating its effects. The walnut (Juglans regia L.) is widely recognized for its diverse range of bioactive compounds, particularly polyphenols, flavonoids, and tocopherols, which exhibit notable antioxidant properties. These beneficial compounds are found in various walnut-based products, including milk, yogurt, cheese substitutes, flowers, protein meals, oils, and extracts from components such as the husk, pellicle, and leaves. Previous studies demonstrated that microbial fermentation using probiotic or non-probiotic starter cultures may significantly enhance the antioxidant capacity of walnut-based products. Outcomes are influenced by factors such as the type of walnut tissue used, the fermentation conditions, the choice of microbial strain, and the extraction method. This review critically summarizes and evaluates current findings on the impact of fermentation on the antioxidant properties of walnuts and walnut-derived products.
https://doi.org/10.1007/s42452-025-08185-6
Improving the protective features of fresh pistachios against chilling injury and enzymatic discoloration through the synergistic application of Ajwain seeds essential oils (Trachyspermum ammi) and carboxymethylcellulose
The thymol fraction present in Ajwain seed essential oil (Aj) exhibits antioxidant properties that can mitigate horticultural crop losses after harvest. This study was designed to analyze the influence of carboxymethyl cellulose (CMC 0.5 %) in combination with three concentrations of Aj (400, 800 and 1200 mg L−1) on fresh ‘Ahmad Aghaei’ pistachio fruits. After drying at ambient temperature and packaging, the fruits were stored at 2 ± 1 °C with 85 ± 2 % relative humidity. The combined treatments of CMC 0.5 % with Aj 400 and 800 scientifically controlled weight loss, chilling injury, decay, hull H2O2 levels, and enzyme activity compared to the control sample over an extended storage duration. The highest levels of chilling injury, decay and POD activity were observed in the samples treated with distilled water (control), while the lowest sensory scores were also recorded in the same treatment. Although CMC + Aj 1200 showed the highest chlorophyll content, it resulted in a negative effect on the aroma index. Combined treatments resulted in the highest lipid and hue index at the end of the storage period. In the control sample, the phenolic compounds decreased by 54 %, whereas the pistachios treated with CMC + Aj 800 experienced a 31 % decrease in phenolics. Overall, the application of CMC + Aj 800 successfully preserved the quantitative and qualitative attributes of Ahmad Aghaei pistachios for up to 50 days.
https://doi.org/10.1016/j.jspr.2025.102858
Replacing Solid Snacks with Almonds or Adding Almonds to the Diet Improves Diet Quality and Compliance with the 2020–25 Dietary Guidelines for Americans: Modeling Analyses of NHANES 2017–23 Data
Background: Healthier between-meal snacks can improve diet quality in the US and globally. Objectives: To assess the impact on diet quality of replacing solid snacks with almonds or adding almonds (30 g) to the diet. Methods: Dietary data for 4333 children (4–19 y) and 10,925 adults (>19 y) came from the National Health and Nutrition Examination Survey (NHANES 2017–23). Nutrient composition data came from the Food and Nutrient Databases for Dietary Studies (FNDDS). Substitution Model 1 replaced all solid snacks with almonds on a per-calorie basis. Model 2 exempted “healthy” snacks. Model 3 added almonds to the observed diet. The Healthy Eating Index (HEI-2020), Nutrient Rich Food Index (NRF), Mean Adequacy Ratio (MAR), and Mean Excess Ratio (MER) were measures of diet quality. Results: Solid snacks provided 329 kcal/day (15.6% of dietary energy), of which 58 kcal came from healthy snacks (2.9%). The 4–13 y age group consumed the most energy from snacks. Diets with almonds replacing solid snacks were lower in added sugar, sodium, and saturated (solid) fat but higher in protein, fiber, mono- and polyunsaturated fats, and magnesium. MAR dietary nutrient density scores were significantly higher, and MER scores were lower. Total HEI-2020 scores rose from 52.4 (observed) to 59.6 (Model 1) and to 60.6 in Model 2_100. The addition of almonds (30 g or 50 g) increased HEI-2020 values to 59.2 and to 61.4, respectively. Several HEI-2020 sub-scores increased as well. The greatest dietary benefits were obtained for children and young adults. Conclusions: Replacing solid snacks with small amounts of almonds led to higher quality modeled food patterns, especially for younger age groups. The DGA 2025–30 should address the inclusion of healthy energy-dense snacks into everyday diets.
https://doi.org/10.3390/nu18010087
Development of Antioxidant Polycaprolactone Films Incorporating Peanut Skin Food Waste Extract for Active Packaging
Biodegradable polycaprolactone (PCL) films were developed with 13% w/w ethanol extract from industrial peanut skin residues (PSE), a rich source of natural antioxidants and antimicrobials. Films retain actives during processing. Antioxidant activity was evaluated via total phenolics, flavonoids, condensed tannins, and radical scavenging assays (DPPH, ABTS). PSE incorporation enhances oxidative thermal stability, increasing oxidation onset temperature (OOT) by 61°C—eliminating the early oxidative stage of neat PCL—and extending oxidation induction time (OIT), without compromising suitability for food packaging. Oxidative stability is maintained after accelerated storage (90 days at 40°C) and repeated migration tests simulating contact with refrigerated fatty foods. Migration assays confirm effective release of actives under repeated use. Mass transfer parameters were obtained by fitting experimental data to Fick's second law and the Arrhenius model, yielding intrinsic diffusion coefficients in 95% ethanol from 5°C to 40°C (4.17 × 10−15–7.1 × 10−14 m2·s−1), eliminating swelling at 40°C. Coefficients fall within typical polymer–antioxidant ranges, reflecting strong retention and controlled release due to the PCL matrix and complex PSE mixture. Overall, the films demonstrate long-term chemical and functional stability, enhanced thermo-oxidative resistance, and controlled antioxidant release, supporting their application in refrigerated, lipid-rich foods within a circular economy framework.
https://doi.org/10.1002/app.70266
‘Divina’: A New Almond Cultivar Characterized by High Nutritional Value, Self-fertility, Late Blooming, and High Productivity
Divina is a new almond [Prunus dulcis (Mill) D.A. Webb] cultivar from the almond breeding program of Institut de Recerca i Tecnologia Agroalimentàries (IRTA; Catalonia, Spain). This cultivar is characterized by its hard-shelled nut, late blooming time, and high productivity. ‘Divina’ is self-fertile and exhibits excellent horticultural performance and chemical composition. Its kernel is attractive with a medium size (1.2 g), comparable to ‘Marcona’ and ‘Nonpareil’. Additionally, ‘Divina’ stands out for its high fat content, oil stability, and kernel firmness.
https://doi.org/10.21273/HORTSCI19148-25
Autoclaved Peanuts Exhibit Reduced Immunoglobulin E Binding and Improved Oral Tolerability
Background: Major peanut allergens are stable and resistant to denaturation under standard cooking conditions, contributing to allergenicity and low rates of developing natural tolerance in allergic individuals. We evaluated the effects of heat and pressure autoclaving on peanut proteins, IgE binding, and oral tolerability. Methods: Raw, roasted, and autoclaved peanut protein extracts were evaluated by Bradford assay, ELISA, and mass spectrometry-proteomics to compare relative amounts of protein, specific IgE binding, and allergen fragmentation. To assess changes in clinical reactivity, we performed skin prick testing (SPT) in 41 subjects using standard and autoclaved peanut extracts. We also performed double-blind oral food challenges (OFC) in 10 peanut-allergic subjects with standard and autoclaved peanuts. Results: Autoclaving at 130°C, 2.4 atm, for 30 min significantly degraded allergens Ara h 1 and 2, and completely degraded Ara h 8. Mass spectrometry-proteomics analysis of size-filtered extracts (< 10 kDa) showed greater numbers and diversity of peptides from peanut proteins and allergens in autoclaved extracts. Autoclaving fragmented proteins into shorter peptides, against which sera from highly allergic patients exhibited a 74% reduction in IgE binding compared to raw peanuts. SPT demonstrated significant decreases in wheal diameters using autoclaved peanut extract (median [IQR] = 5 mm [2, 9]) compared to commercial extract (10 mm [6, 15]; p < 0.001). All OFC subjects tolerated the maximum cumulative autoclaved peanut dose (444 mg) versus standard peanut (median: 9 mg, range: [1, 44]). Conclusions: Autoclaving peanuts induces important chemical changes including fragmentation, leading to decreased peanut allergenicity and consequently increased tolerability. This has the potential for novel immunotherapeutic approaches with more favorable side effect profiles.
https://doi.org/10.1111/all.70208
New US Dietary Guidelines Emphasize Protein Consumption
Photo credit: realfood.gov
On January 7, 2026, the U.S. Department of Health and Human Services and the U.S. Department of Agriculture unveiled the latest version of the Dietary Guidelines for Americans, which will apply until 2030.
The new guidelines urge people to prioritize protein foods at every meal. Among other sources of protein, the guidelines recommend consuming “a variety of plant-sourced protein foods,” including nuts and legumes.
Intake recommendations vary depending on individual caloric requirements, as set out in the daily servings guide released alongside the new guidelines. People following a 2,000 calorie/day diet are encouraged to eat 3-4 daily servings of “protein foods.” Examples of servings of protein foods include “1 oz nuts or seeds” and “2 tbsp nut or seed butter.”
According to the new guidelines, dried fruit with no or very limited added sugars “can also be good options” for meeting target intake levels for fruit. People following a 2,000 calorie/day diet are encouraged to eat 2 servings of fruit per day, with one serving of dried fruit is defined as ½ cup.
Almond Supplementation Shown to Improve Cardiovascular Risk Markers in Pregnant Women
According to a recent study published in the Journal of Nutrition, daily almond supplementation, especially at a higher dose, may significantly improve certain cardiovascular risk markers in pregnant women with hypertension and dyslipidemia—conditions associated with increased risk of adverse maternal and fetal outcomes.
In this 12-week randomized controlled trial, researchers assessed the effects of almond supplementation at two different doses (10 grams/day and 25 grams/day) on blood pressure, lipid profile, and heart rate in 103 pregnant women with confirmed hypertension and/or dyslipidemia. Participants were randomly assigned to one of three groups: a group instructed to eat 10 grams of almonds per day, a group instructed to eat 25 grams of almonds per day, or a control group. The researchers measured changes in systolic and diastolic blood pressure every 4 weeks. They also assessed serum triglycerides, total cholesterol, LDL (“bad”) cholesterol, HDL (“good”) cholesterol, and heart rate at baseline and at week 12.
After 12 weeks, the researchers found that almond supplementation had significantly improved blood pressure and lipid profile, especially at the higher dose of 25 grams/day. These findings highlight the potential role of almonds as a complementary dietary strategy for managing cardiometabolic risk in pregnancy.
Arslan, J., Najam, Z., Abdullah, H., Siddiqi, H. S., Bano, R., Gilani, A. U., & Jamshed, H. (2025). Daily Almond Supplementation Improves Blood Pressure and Lipid Profile in Pregnant Women with Hypertension and Dyslipidemia: A Randomized Controlled Trial. The Journal of Nutrition, 101270. Advance online publication.
Peanut Allergies Decline After Publication of Early Introduction Guidelines
A recent study published in Pediatrics suggests that rates of peanut allergy in young children in the United States declined significantly following the publication of guidelines encouraging early peanut consumption in infancy.
The study set out to examine changes in peanut allergy incidence following the 2015 publication of a consensus statement backed by nearly a dozen medical associations that recommended early peanut introduction for high-risk infants. The publication of the consensus statement marked a key milestone in the shift away from the previous medical guidance instructing parents to delay introduction of peanut.
Using electronic health record data from around 40,000 children aged 0-3 years in US primary care settings, researchers looked at how food allergy diagnoses changed from the 2012-2014 pre-guidelines period to the 2015-2017 post-guidelines period.
The findings showed that the cumulative incidence of immunoglobulin E–mediated peanut allergy fell from 0.79% before the guidelines to 0.53% after their introduction—a relative reduction of around one-third. Rates declined even further, to 0.45%, after the release of addendum guidelines in 2017. The researchers also found that the cumulative incidence of tree nut allergy fell from 0.12% before the guidelines to 0.08% after their publication.
Overall, the findings suggest that the shift toward earlier nut introduction in infancy has been accompanied by a measurable decline in diagnosed nut allergies at the population level.
Gabryszewski, S. J., Dudley, J., Faerber, J. A., Grundmeier, R. W., Fiks, A. G., Spergel, J. M., & Hill, D. A. (2025). Guidelines for Early Food Introduction and Patterns of Food Allergy. Pediatrics, 156(5), e2024070516.
Food Safety Update
Codex Alimentarius: Publication of Revised Code of Practice on Aflatoxin Contamination in Peanuts
Codex Alimentarius recently published a revised version of the Code of Practice for the Prevention and Reduction of Aflatoxin Contamination in Peanuts.
As background, a Codex electronic working group concluded in 2024 that the Code, first published in 2004, should be revised on the basis of new information available on risk management measures to reduce aflatoxins in peanuts. The group submitted a discussion paper and proposed draft of the Code for the consideration of the Codex Committee on Contaminants in Foods (CCCF) in June 2025. The Codex Alimentarius Commission (CAC48) adopted the revised Code in November 2025, and the new text was recently published on the Codex website.
Eurasian Economic Union: New Phytosanitary Requirements for Dried Grapes
Russia has notified the World Trade Organization of a draft decision of the Council of the Eurasian Economic Commission on amendments to the common quarantine phytosanitary requirements for regulated products and pests at the customs border and in the customs territory of the Eurasian Economic Union. Among other provisions, the draft envisages requirements for dried grapes to ensure the absence of the Comstock mealybug (Pseudococcus comstocki). The deadline for comments is February 27, 2026.