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Almond processing generates a high quantity of by-products, presenting the untapped potential for alternative applications and improved sustainability in production. This study aimed to evaluate whether the incorporation of almond by-products (hulls/shells) can improve the biochemical characteristics of green bean pods when used as an alternative to traditional growing media in green bean plants. Four substrates were prepared: the Control substrate (C): 70% peat + 30% perlite; substrate (AS): 70% peat + 30% shells; substrate (AH): 70% peat + 30% perlite + 1 cm hulls as mulch; substrate (MIX): 70% peat + 15% shells + 15% hulls. Plants were grown in each of these substrates and subjected to two irrigation levels, 100% and 50% of their water-holding capacity. Biochemical parameters (photosynthetic pigments, total phenolics, flavonoids, ortho-diphenols, soluble proteins, antioxidant capacity) and color were evaluated in the harvested pods. Results showed that pods from plants growing in AH substrate presented statistically significant higher values in their total phenolic content, while AS and MIX substrates did not reveal significant benefits. Summarily, this study highlights the potential of almond hulls as a promising medium for green bean cultivation, particularly when employed as mulch. Further research is recommended to gain a more comprehensive understanding of the application of almond by-products as natural fertilizers/mulch. [ABSTRACT FROM AUTHOR]

The global sustainability policy emphasizes reusing of agri-food waste and by-products to enhance food bioactive properties. Thus, brioches were processed incorporating almond skin powder (ASP): control (CTR), without ASP addition; 5-ASP, with 5% (w/w) ASP; and 10-ASP, with 10% (w/w) ASP. Seven different brioches shapes were obtained for each recipe. Flavonoids were mainly detected in Tuono almond skin by Ultra-High Performance Liquid Chromatography coupled to High-Resolution Mass Spectrometry (UHPLC-HRMSMS), in particular, flavan-3-ol monomers. The ethanolic extract of Tuono almond skins contained polar lipids (oxylipins and phospholipids). Gas Chromatography–Mass Spectrometry (GC-MS) identified six major fatty acids, mainly oleic acid (48.01%). Photothermal degradation impact on bioactive compounds was evaluated using a first-order kinetic model. Antioxidant activity was studied using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), 2,2-diphenyl-1-picrylhydrazyl and β-carotene bleaching test. α-amylase, α-glucosidase, and lipase inhibitory effect were also tested. The acidification of the doughs was consistent across all trials. Lactic acid bacteria and yeast levels increased. Importantly, the final products were free from undesirable microorganisms. The addition of ASP led to reduced weight loss and specific volume for all seven brioche types. Furthermore, the firmness, crumb structure, and sensory profile of the final products were noticeably influenced. Tasters clearly favoured the Treccina brioches. The production of sweet leavened baked goods was carried out in triplicate in two independent experiments. The statistical model applied to the data considered the effects of brioche shape and the addition of ASP. Kinetic data revealed that the half-life extension for both total phenol and flavonoid content was observed in the 10-ASP sample (18.00382). 10-ASP sample exhibited promising ABTS radical scavenging activity, with inhibitory concentration 50% (IC50) values of 18.64 mg/mL after 9 days of photothermal degradation. Moreover, when testing 10-ASP Treccina against α-amylase and α-glucosidase, the IC50 values were 198.16 and 190.23 μg/mL, respectively, even after 9 days.

The present work reports the application of powdered almond skin (PAS) for industrial bread production. Three trials were conducted involving seven bread shapes, including control production (CTR), and two experimental productions with PAS addition [5–10 % (w/w), 5-PAS and 10-PAS, respectively]. Sourdough inoculum determined the acidification of all doughs and the levels of lactic acid bacteria increased. Spore-forming aerobic bacteria, members of the Enterobacteriaceae family, and total coliforms were not detected until the end of the fermentation process. PAS addition determined a lower weight loss, an increase of firmness, a diminution of specific volume, and a different sensory profile of the breads. Mafalda was the most appreciated bread shape and was subjected to photothermal aging. 10-PAS sample, after nine-day stress, still showed a significant total phenolic compound TPC content (111.0 mg GAE/g extract). The radical scavenging potential increased with PAS with a final IC50 of 103.3 μg/mL in 10-PAS breads. Experimental breads exhibited a notable enhancement in protection against lipid peroxidation. Mold-free shelf life assessment showed a 10-day shelf life for CTR breads, while a 12-day shelf life in presence of PAS. Collectively, the data suggest that PAS holds significant promise as a functional additive for industrial production of bread.

In this work, we studied the potential of supercritical fluid CO2 technology to extract almond wastes and obtain a fibre product rich in minerals and phenolics without the use of an extraction co-solvent. The analysis of phenolics in the resulting extracted product was performed using liquid chromatography–tandem mass spectrometry (LC-MS/MS) and showed vanillin, catechin, and dihydroxybenzoic, vanillic, and syringic acids as main phenolic compounds (PC). In addition, the analysis of minerals carried out using inductively coupled plasma optical emission spectroscopy (ICP-OES) showed a wide range of macroelements like magnesium (Mg) and potassium (K) in quantities of up to 1.7 g/kg (Mg) and 6 g/kg (K), representing a value matrix that may be integrated into functional drinks targeting athletic people while promoting a circular economy and food up-cycling. [ABSTRACT FROM AUTHOR]

Almond processing generates a high quantity of by-products, presenting the untapped potential for alternative applications and improved sustainability in production. This study aimed to evaluate whether the incorporation of almond by-products (hulls/shells) can improve the biochemical characteristics of green bean pods when used as an alternative to traditional growing media in green bean plants. Four substrates were prepared: the Control substrate (C): 70% peat + 30% perlite; substrate (AS): 70% peat + 30% shells; substrate (AH): 70% peat + 30% perlite + 1 cm hulls as mulch; substrate (MIX): 70% peat + 15% shells + 15% hulls. Plants were grown in each of these substrates and subjected to two irrigation levels, 100% and 50% of their water-holding capacity. Biochemical parameters (photosynthetic pigments, total phenolics, flavonoids, ortho-diphenols, soluble proteins, antioxidant capacity) and color were evaluated in the harvested pods. Results showed that pods from plants growing in AH substrate presented statistically significant higher values in their total phenolic content, while AS and MIX substrates did not reveal significant benefits. Summarily, this study highlights the potential of almond hulls as a promising medium for green bean cultivation, particularly when employed as mulch. Further research is recommended to gain a more comprehensive understanding of the application of almond by-products as natural fertilizers/mulch.

The almond industry produces, by bleaching and stripping, two by-products: blanched skin (BS) and blanch water (BW). The aim of this study was to investigate the nutritional and polyphenolic profile, as well as the antioxidant, antimicrobial, antiviral, and potential prebiotic effects of BS and BW from three different Sicilian cultivars. The total phenols and flavonoids contents were ≥1.72 and ≥0.56 g gallic acid equivalents and ≥0.52 and ≥0.18 g rutin equivalents/100 g dry extract (DE) in BS and BW, respectively. The antioxidant activity, evaluated by 2,2-diphenyl-1-picrylhydrazyl scavenging ability, trolox equivalent antioxidant capacity, ferric-reducing antioxidant power, and oxygen radical absorbance capacity, was ≥3.07 and ≥0.83 g trolox equivalent/100 g DE in BS and BW, respectively. Isorhamnetin-3-O-glucoside was the most abundant flavonoid detected in both by-products. No antimicrobial effect was recorded, whereas BS samples exerted antiviral activity against herpes simplex virus 1 (EC50 160.96 μg/mL). BS also showed high fibre (≥52.67%) and protein (≥10.99) contents and low fat (≤15.35%) and sugars (≤5.55%), making it nutritionally interesting. The present study proved that the cultivar is not a discriminating factor in determining the chemical and biological properties of BS and BW. [ABSTRACT FROM AUTHOR]

Lignin, as the most abundant aromatic polymer on the earth, was assessed considering aspects such as sources, type, structure, and isolation processes. Thus, almond shells and almond stems were chosen to aim to represent two different botanical origins, and a study was evaluated to determine their potential properties such as their structural characterization, quantification of their functional groups, and evaluation of thermal properties. A significant difference in the structural characteristics, molecular mass distribution, and thermal properties were observed in each starting material. The almond shells lignin shows a greater content of G-units (66%) than S-units (27%), in contrast to the almond stems lignin, where H-units (60%) are greater than G-units (30%). Therefore, the almond stems lignin has the lowest amount of sugar (15.78%), the highest weight-average molecular weight (9973 g·mol−1), the lowest polydispersity index (1.58), and the greatest thermal stability. The antioxidant properties of extracted lignins were evaluated and compared to other commercial products. All the tested lignins exhibit good antioxidant properties that are revealed by the obtained EC50 values, especially for almond stems lignin (EC50=0.485 µg·mL−1). As a result of this finding, using lignins extracted from almond by-products as a new antioxidant formulation in textile applications could be very promising. [ABSTRACT FROM AUTHOR]

In this work, we studied the potential of supercritical fluid CO2 technology to extract almond wastes and obtain a fibre product rich in minerals and phenolics without the use of an extraction co-solvent. The analysis of phenolics in the resulting extracted product was performed using liquid chromatography–tandem mass spectrometry (LC-MS/MS) and showed vanillin, catechin, and dihydroxybenzoic, vanillic, and syringic acids as main phenolic compounds (PC). In addition, the analysis of minerals carried out using inductively coupled plasma optical emission spectroscopy (ICP-OES) showed a wide range of macroelements like magnesium (Mg) and potassium (K) in quantities of up to 1.7 g/kg (Mg) and 6 g/kg (K), representing a value matrix that may be integrated into functional drinks targeting athletic people while promoting a circular economy and food up-cycling.

Almond production generates large amounts of by-products rich in polyphenols. In this study, almond skin was explored as a valuable food ingredient in bread making. To this purpose, almond skin was used to produce functional products modifying a traditional sourdough bread recipe. The doughs were prepared replacing semolina with powdered almond skin (PAS) at 5 and 10 % (w/w). Sourdough inoculum was started with a mix of lactic acid bacteria (LAB) and propagated in semolina until reaching pH 3.7. The pH of PAS added breads was higher than that of control (CTR) breads before and after fermentation. Plate counts showed a similar evolution of LAB and total mesophilic microorganisms, but members of Enterobacteriaceae and coliform were detectable in PAS doughs. Illumina data clearly showed a dominance of lactobacilli in all trials, but PAS doughs displayed the presence of Bacillus. The final bread characteristics were influenced by PAS and its addition percentage; in particular, crust and crumb colour resulted darker, the alveolation decreased and, regarding sensory attributes, odour intensity increased, while bread odour diminished. In presence of PAS, bread emissions were characterized by lower percentages of alcohols and aromatic hydrocarbons and higher percentages of the other volatile compound classes, especially terpenoids like β-pinene, β-myrcene and limonene than CTR trial. After in vitro simulated digestion, the final release of phytochemicals from 10 % PAS bread was almost 100 %. Thus, PAS determined an increase of the antioxidant capacity of the breads. Phytochemicals released from digested PAS-fortified bread can provide antioxidant protection in a complex biological environment such as human intestinal-like cells. Besides the positive functional properties of PAS, this work also evidenced the hygienic issues of almond skin and, in order to avoid potential risks for the human health, highlighted the need to preserve its microbiological characteristics during storage for their reuse in bread production. • Powder almond skin (PAS) did not affect the growth of starter lactic acid bacteria. • PAS slightly slowed down the acidification process. • Lactobacilli were absent in PAS, but detected in all doughs at relative abundances. • PAS phytochemicals provided antioxidant protection to human intestinal-like cells. [ABSTRACT FROM AUTHOR]

Almonds are considered one of the most valuable fruits worldwide due to its high nutritional value. Moreover, a growing attention has been paid over the last years to other parts of the fruit, such as skins, shells or hulls, which are commonly found as almond by-products and scarcely exploited for valorization. In this study, two approaches were evaluated. Firstly, a green innovative processing technology, pulsed electric fields (PEF), was applied for the first time to assist the extraction of antioxidant compounds from almond hull biomass (AH). In particular, this technology was used with the aim of developing a feasible valorization strategy, being a sustainable alternative for polyphenols extraction compared to traditional methods. Then, the total phenolic content (TPC) and the antioxidant activity (TEAC and ORAC values) were measured, obtaining a higher extraction of TPC and TEAC values when PEF was used compared to conventional soaking. Secondly, the characterization of AH by means of fiber, ultimate and proximate analysis was carried out. Ultimate and proximate analysis provided information about the exploitation towards bioenergy and biofuels, demonstrating the so-called derived AH-EFB being useful for that purpose. Moreover, the high percentage in terms of carbohydrates suggests that AH could be a useful source for high-added-value chemicals, such as levulinic acid, furfural and 5-hidroximethylfurfural, displaying an interesting energetic valorization route for this biomass. • Almond by-products are useful to obtain bioenergy and biofuels. • Almond hull could be a good source of high-added-value chemicals. • PEF treatment increased the extraction of polyphenols and antioxidant activity. [ABSTRACT FROM AUTHOR]