Almond (Prunus dulcis L.) protein quality

Bioaccessibility and Digestibility of Proteins in Plant-Based Drinks and Cow's Milk: Antioxidant Potential of the Bioaccessible Fraction

During the last years, a strong increase in the sales volume and consumption of plant-based drinks was observed, which were partly used as an alternative to cow's milk. As milk is a relevant protein source in many countries, we have investigated the protein bioaccessibility and digestibility of soy, almond, and oat drinks in comparison to milk using the tiny-TIMsg gastrointestinal model. The relative protein digestibility of all products was between 81% (soy drink) and 90% (milk). The digestible indispensable amino acid score (DIAAS) in vitro method was used to estimate the protein nutritional quality. The highest DIAAS values were obtained for milk in tryptophan (117%) and soy drink in sulfur containing amino acids (100%). Oat drink was limited in lysine (73%), almond drink in lysine (34%) and the sulfur containing amino acids (56%). Additionally, the antioxidant activity of the bioaccessible fractions was analyzed using Trolox equivalent antioxidative capacity and oxygen radical absorbance capacity assays, revealing a higher antioxidative potential of milk and soy drink compared to oat and almond drink.

A Review of Plant-Based Drinks Addressing Nutrients, Flavor, and Processing Technologies

Plant-based drinks have garnered significant attention as viable substitutes for traditional dairy milk, providing options for individuals who are lactose intolerant or allergic to dairy proteins, and those who adhere to vegan or vegetarian diets. In recent years, demand for plant-based drinks has expanded rapidly. Each variety has unique characteristics in terms of flavor, texture, and nutritional composition, offering consumers a diverse range of choices tailored to meet individual preferences and dietary needs. In this review, we aimed to provide a comprehensive overview of the various types of plant-based drinks and explore potential considerations including their nutritional compositions, health benefits, and processing technologies, as well as the challenges facing the plant-based drink processing industry. We delve into scientific evidence supporting the consumption of plant-based drinks, discuss their potential roles in meeting dietary requirements, and address current limitations and concerns regarding their use. We hope to illuminate the growing significance of plant-based drinks as sustainable and nutritious alternatives to dairy milk, and assist individuals in making informed choices regarding their dietary habits, expanding potential applications for plant-based drinks, and providing necessary theoretical and technical support for the development of a plant-based drink processing industry.

Phytochemistry and pharmacology of Armeniacae semen Amarum: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Armeniacae Semen Amarum (Prunus armeniaca L. var. ansu Maxim., Ku xingren, bitter almond, ASA) is an important medicine in Traditional Chinese Medicine (TCM). It is widely used because of its remarkable curative effect in relieving cough and asthma, moistening intestines and defecating.

AIM OF THE REVIEW

This review aims to enlighten the deeper knowledge about ASA, giving a comprehensive overview of its traditional uses, phytochemistry, pharmacology and toxicology for future investigation of plant-based drugs and therapeutic applications.

MATERIALS AND METHODS

The databases used are Web of Science, PubMed, Baidu academic, Google academic, CNKI, Wanfang and VIP . In addition, detailed information on ASA was obtained from relevant monographs such as Chinese Pharmacopoeia.

RESULTS

The active components of ASA mainly include amygdalin, bitter almond oil, essential oil, protein, vitamin, trace elements and carbohydrates. The pharmacological studies have shown that ASA has beneficial effects such as antitussive, antiasthmatic, anti-inflammatory, analgesic, antioxidant, antitumour, cardioprotective, antifibrotic, immune regulatory, bowel relaxation, insecticidal, etc. CONCLUSIONS: Many reports have been published on ASA's various active ingredients and biological uses. However, only a few reviews on its phytoconstituents and pharmacological uses. In addition, the exploration and development of ASA in other fields also deserve more attention in future research.

Almond (Amygdalus communis L.) kernel protein: A review on the extraction, functional properties and nutritional value

Almond (Amygdalus communis L.) kernel, a source of nutrients in many traditional diets, is being used more frequently as a nutritious snack and component. It is well known that almond kernels are a protein-rich food. Compared to the amino acid profile recommended by FAO, almond kernel protein is an ideal protein with perfect balance of amino acids. It also has a variety of better functional properties such as solubility, emulsifying ability, oil absorption capacity and foaming ability. pH and ion strength have significant influences on these functional properties. Furthermore, almond kernel protein is easily digested and absorbed by the human body. So almond kernel protein can be used as a high-quality protein resource. This review describes the techniques for extracting almond kernel protein, as well as its functional properties, nutritional worth, and applications. The purpose of this review is to provide ideas for the effective use of almond kernel protein and the creation of related products.

A review on some properties of almond: ımpact of processing, fatty acids, polyphenols, nutrients, bioactive properties, and health aspects

This review was focused on the proximate compounds, nutritional values, total phenolic, flavonoid, antioxidant activity, fatty acid profile, polyphenols, health aspects and uses of almond kernel and oils. Almond contained about 24-73% crude oil, 50-84% oleic and 6-37% linoleic acids, 77-3908 mg/kg β-stosterol and 5-8 mg/100 g β-tocopherol. Almonds are a good source of mono- and unsaturated fatty acids, phytochemicals, bioactive components, minerals, vitamin E, polyphenols and phytosterols and at the same time almonds have healing effects. Since almond seeds or seed oils have versatile uses, they are consumed on their own or as part of a range of food products. Almonds are considered a healthy snack when consumed due to their potential cardioprotective effects. Since the composition of almonds and its effects on health will be effective both during cultivation and processing, studies should be carried out in a way that preserves the product quality.

Graphical abstract

In this study, the proximate compounds, harvest and irrigation effect, nutritional values (protein, amino acids, vitamins minerals), total phenol, flavonoid, antioxidant activity, fatty acid profile, polyphenols, and uses of almond kernel and oils were summarized.

Observational and clinical evidence that plant-based nutrition reduces dietary acid load

Contemporary diets in Western countries are largely acid-inducing and deficient in potassium alkali salts, resulting in low-grade metabolic acidosis. The chronic consumption of acidogenic diets abundant in animal-based foods (meats, dairy, cheese and eggs) poses a substantial challenge to the human body's buffering capacities and chronic retention of acid wherein the progressive loss of bicarbonate stores can cause cellular and tissue damage. An elevated dietary acid load (DAL) has been associated with systemic inflammation and other adverse metabolic conditions. In this narrative review, we examine DAL quantification methods and index observational and clinical evidence on the role of plant-based diets, chiefly vegetarian and vegan, in reducing DAL. Quantitation of protein and amino acid composition and of intake of alkalising organic potassium salts and magnesium show that plant-based diets are most effective at reducing DAL. Results from clinical studies and recommendations in the form of expert committee opinions suggest that for a number of common illnesses, wherein metabolic acidosis is a contributing factor, the regular inclusion of plant-based foods offers measurable benefits for disease prevention and management. Based on available evidence, dietary shifts toward plant-based nutrition effectively reduces dietary-induced, low-grade metabolic acidosis.

Critical overview of biorefinery approaches for valorization of protein rich tree nut oil industry by-product

This review explores reutilization opportunities of protein-rich bio-waste derived from the major tree nuts (almonds, walnuts, and cashew nuts) oil processing industries through biorefinery strategies. The mechanically pressed out oil cakes of these nuts have high protein (45-55%), carbohydrate (30-35%), and fiber that could be utilized to produce bioactive peptides, biofuels, and dietary fiber, respectively; all of which can fetch substantially greater value than its current utilization as a cattle feed. Specific attention has been given to the production, characterization, and application of nut-based de-oiled cake hydrolysates for therapeutic benefits including antioxidant, antihypertensive and neuroprotective properties. The often-neglected safety/toxicological evaluation of the hydrolysates/peptide sequences has also been described. Based on the available data, it is concluded that enzymatic hydrolysis is a preferred method than microbial fermentation for the value addition of de-oiled tree nut cakes. Further, critical insights on the existing literature as well as potential research ideas have also been proposed.

Actinidin in Green and SunGold Kiwifruit Improves Digestion of Alternative Proteins—An In Vitro Investigation

Both Hayward (green) and SunGold (gold) kiwifruit varieties contain a proteolytic enzyme, actinidin, that has been reported to enhance the upper tract digestion of animal proteins. Unlike the other gold varieties, which do not contain any actinidin, the SunGold variety contains significantly higher actinidin activity, but its activity is still much lower than that present in the green (Hayward) fruit. The objective of this study was to determine the effectiveness of actinidin in Hayward and SunGold kiwifruit in digesting alternative proteins, including pea protein, almonds, tofu, and quinoa. The protein sources were digested using a three-stage in vitro oral-gastro-small intestinal digestion model. The findings showed that both kiwifruit extracts enhanced the breakdown (observed through SDS-PAGE) for all the studied protein sources, particularly during gastric digestion, possibly due to higher actinidin activity at gastric pH. The increase in the rate of protein breakdown was probably due to the broader specificity of actinidin compared to pepsin. For many protein sources, most of the intact proteins disappeared within the first few minutes of gastric digestion with added kiwifruit extract. Green kiwifruit extract, due to its higher actinidin activity, had a higher effect on protein breakdown than the SunGold extract. However, for some proteins and under certain digestion conditions, SunGold extract resulted in higher protein breakdown. The latter, in the absence of any digestive enzymes, also led to some protein breakdown during the small intestinal digestion phase, which was not the case for the green kiwifruit extract. The green kiwifruit extract led to the greater breakdown of polypeptide chains of Pru-du 6, a major allergen in almonds. The results, for the first time, suggest that both Hayward and SunGold kiwifruit can lead to improved breakdown and digestion of alternative proteins when consumed as part of a meal; and therefore, have the potential to be used as a digestive aid in population groups looking to achieve faster and greater protein digestion such as athletes, elderly and people with the impaired digestive system.

Corrigendum: Current concepts and unresolved questions in dietary protein requirements and supplements in adults

[This corrects the article DOI: 10.3389/fnut.2017.00013.].

Plant-Based Formulas and Liquid Feedings for Infants and Toddlers

Exclusive breastfeeding is the recommended feeding for all infants. Recent research has focused on the importance of balanced feeding during the first 1000 days, starting at conception with a balanced diet of the pregnant woman, up to the age of two years. The following step, a balanced diet after the age of two years is a challenge, as the dietary intake becomes more diversified. The role of young-child formula in this process is debated. This paper discusses the use of planted-based drinks, since they are a valuable and progressively more popular alternative for cow's milk, if nutritionally adapted to the requirements of toddlers. Plant-based drinks are per definition lactose free.

Brief Research Report: Estimation of the Protein Digestibility-Corrected Amino Acid Score of Defatted Walnuts

Introduction: Walnuts are considered a good source of essential fatty acids, which is unique among tree nuts. Walnuts are also composed of about 10–15% protein, but the quality of this protein has not been evaluated. Pistachios and almonds have been evaluated for their protein content using a protein digestibility-corrected amino acid score (PDCAAS), but it is unclear how the quality of protein in walnuts relates to that in other commonly consumed tree nuts. The objective of this study was to substantiate the protein quality of walnuts by determining their PDCAAS.

Methods: A small, 10-day dietary intervention trial was conducted using male Sprague-Dawley rats (n = 8, 4 per group) with two diets: a nitrogen-free diet and a diet containing protein exclusively from defatted walnuts. Feed intake and fecal output of nitrogen were measured to estimate the true protein digestibility, and the amino acid compositions of walnuts compared to child and adult populations were used to calculate amino acid scores (AAS) and PDCAAS.

Results: The true protein digestibility score of raw walnuts was calculated to be 86.22%. Raw walnuts contained 15.6 g protein/g walnut with AAS of 0.45 and 0.63 for children aged 6 months to 3 years and 3–10 years, respectively. For each population, a PDCAAS of 39 and 46% was calculated, respectively, using a protein conversion constant of 5.30. Using a protein constant of 6.25, a PDCAAS of 39% (6 months - 3 years) or 46% (3-10 years) was calculated.

Conclusions: This is the first known assessment of the PDCAAS of walnuts. Like almonds, they appear to have a low-to-moderate score, indicating they are not a quality source of protein.

Almond By-Products: Valorization for Sustainability and Competitiveness of the Industry

The search for waste minimization and the valorization of by-products are key practices for good management and improved sustainability in the food industry. The production of almonds generates a large amount of waste, most of which is not used. Until now, almonds have been used for their high nutritional value as food, especially almond meat. The other remaining parts (skin, shell, hulls, etc.) are still little explored, even though they have been used as fuel by burning or as livestock feed. However, interest in these by-products has been increasing as they possess beneficial properties (caused mainly by polyphenols and unsaturated fatty acids) and can be used as new ingredients for the food, cosmetic, and pharmaceutical industries. Therefore, it is important to explore almond’s valorization of by-products for the development of new added-value products that would contribute to the reduction of environmental impact and an improvement in the sustainability and competitiveness of the almond industry.

Replacement of animal proteins in food: How to take advantage of nutritional and gelling properties of alternative protein sources

Given the growing world population, there is a need to balance animal and vegetable sources of dietary protein and to limit overall protein resources, and food formulation has to consider alternative protein sources as a way to meet human requirements. The protein concentration, essential amino acids (EAA) of all protein sources were analyzed with respect to human needs along with additional macronutrients of nutritional and energy interest (i.e. carbohydrates and lipids). New indexes are proposed to classify the alternative protein sources considering their EAA balance and how it may change during food processing. A global overview of all protein sources is provided including the quantity of food and associated caloric intakes required to fulfill our daily protein needs. As texture is a key parameter in food formulation, and is often influenced by protein gelation, we conducted an exhaustive review of the literature in a large scientific database on the ability of proteins from all sources to go through the sol-gel transition with the corresponding physical-chemical conditions. Traditional and innovative recipes are discussed and some improvement are proposed in terms of their ability to fulfill human needs for EAA and food and caloric intakes.

Variability of Chemical Profile in Almonds (Prunus dulcis) of Different Cultivars and Origins

Almonds show a great variability in their chemical composition. This variability is a result of the existence of a diverse range of almond cultivars, the self-incompatibility of most almond cultivars, and the heterogeneous harvesting conditions found around the different locations where almons are grown. In the last years, the discrimination among almond cultivars has been the focal point of some research studies to avoid fraud in protected geographical indications in almond products and also for selecting the best cultivars for a specific food application or the most interesting ones from a nutritional point of view. In this work, a revision of the recent research works related to the chemical characterization and classification of almond cultivars from different geographical origins has been carried out. The content of macronutrients, tocopherols, phytosterols, polyphenols, minerals, amino acids, and volatile compounds together with DNA fingerprint have been reported as possible cultivar and origin markers. The analysis of the results showed that no individual almond compound could be considered a universal biomarker to find differences among different almond cultivars. Hence, an adequate selection of variables or the employment of metabolomics and the application of multivariate statistical techniques is necessary when classification studies are carried out to obtain valuable results. Meanwhile, DNA fingerprinting is the perfect tool for compared cultivars based on their genetic origin.

In Vitro Protein Digestibility and Fatty Acid Profile of Commercial Plant-Based Milk Alternatives

Plant-based milk alternatives (PBMA) are a new popular food trend among consumers in Europe and North America. The forecast shows that PBMA will double their value by 2023. The objective of this study was to analyze the nutritional value of commercial products in terms of their fatty acid profile and protein digestibility from commercial PBMA. Eight commercially available PBMA were selected for fatty acid analysis, performed with gas chromatography of methylated fatty acids (GC-FAME), and, from these, four commercial products (almond drink, hemp drink, oat drink, and soy drink) were selected for a short-term in vitro protein digestibility (IVPD) analysis. The fatty acid analysis results showed that most of the products predominantly contained oleic acid (C18:1 ω-9) and linoleic acid (C18:2 ω-6). Hemp drink contained the highest omega-6/omega-3 (ω6/ω3) ratio among all tested products (3.43). Oat drink and almond drink were the PBMA with the highest short-term protein digestibility, non-significantly different from cow's milk, while soy drink showed the lowest value of protein digestibility. In conclusion, PBMA showed a significant variability depending on the plant source, both in terms of fatty acid composition and protein digestibility. These results provide more in-depth nutritional information, for future product development, and for consumer's choice.

Review about Non-Lipid Components and Minor Fat-Soluble Bioactive Compounds of Almond Kernel

This work presents a bibliographic review about almond kernel non-lipid components, in particular about the protein fraction, the carbohydrates and the mineral fraction. In addition, other fat-soluble phytochemicals which are present in minor concentrations but show important antioxidant activities are reviewed. Almond kernel is a rich protein food (8.4-35.1%), in which the globulin-albumin fraction dominates, followed by glutelins and prolamins. Within the almond kernel protein profile, amandine dominates. Free amino acids represent a small amount of the total nitrogen quantity, highlighting the presence of glutamic acid and aspartic acid, followed by arginine. Carbohydrates that appear in almond kernels (14-28%) are soluble sugars (mainly sucrose), starch and other polysaccharides such as cellulose and non-digestible hemicelluloses. Regarding the mineral elements, potassium is the most common, followed by phosphorus; both macronutrients represent more than 70% of the total mineral fraction, without taking into account nitrogen. Microminerals include sodium, iron, copper, manganese and zinc. Within the phytochemical compounds, tocopherols, squalene, phytosterols, stanols, sphingolipids, phospholipids, chlorophylls, carotenoids, phenols and volatile compounds can be found.

Nutritional quality of formulated complementary diet from defatted almond seed, yellow maize and quality protein maize flours

Traditional complementary foods are mainly starchy foods with limiting nutrient quality and can be fortified using protein rich crops like almond seed. This research thus aimed at investigating the nutritional quality of the formulated complementary diet from locally available almond seeds (Prunus amygdalus), high quality protein (QPM) and yellow maize after blending into flours. The proximate and amino acid compositions, in vitro protein qualities and functional properties of the blended flours were determined using standard methods. The in vivo studies involved feeding the weanling Wister albino rats with blended flours and commercial Cerelac (control), followed by hematological and histopathological determinations, while sensory attributes were evaluated by the semi-trained panelists. The protein contents of the flour blends (24–28%) were significantly (p < 0.05) better with adequate indispensable amino acids and improved functionalities than commercial cerelac (23%). Comparatively, the dried germinated QPM (DGQPM) has significant (p < 0.05) higher biological value (~ 37%) than fermented high QPM (FHQPM) (~ 30%), thereby indicating that the germination process improved protein quality of the diets. Besides, the in vivo data showed a positive effect of germination process as the rats fed with DGQPM has low white blood cells (30 × 102) compared to FHQPM (42 × 102) and cerelac (51 × 102). However, the fermentation process improved the packed cell volume of rats fed with FHQPM (49%) when compared to DGQPM and cerelac (47%). The formulated diets have no negative effects on the protein content (45.19–51.88 mg N/g) and weight (0.25–1.36 g) of the internal organs (liver, kidney and tissue) of the animals when compared to cerelac (53.72–55.04 mg N/g; 0.25–1.98 g), respectively. The panelists generally accepted all the formulated diets, hence encouraging their utilization in the global preparation of complimentary foods for young children to meet their nutritional needs and adding value to the locally produced underutilized almond seeds.

Physicochemical and microstructural properties and probiotic survivability of symbiotic almond yogurt alternative using polymerized whey protein as a gelation agent

A plain symbiotic almond yogurt-like product was formulated and developed using a plant-based starter YF-L02 (Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus supplemented with Lactobacillus acidophilus, Lactobacillus paracasei, and Bifidobacterium animalis) and inulin; 0.6% polymerized whey protein (PWP), 0.3% pectin, and 0.05% xanthan gum were optimized for the formula of the almond yogurt alternative. Two groups with/without calcium citrate and vitamin D₂ were prepared and analyzed for chemical composition, changes in pH, viscosity, and probiotic survivability during storage at 4 °C for 10 weeks. The results showed that (1) over 10 weeks storage, the differences in the pH, viscosity, and probiotic survivability between the control and the fortified samples were not significant (P > 0.05); (2) the pH of both yogurt samples decreased 0.2 units while their viscosity slightly increased during storage; (3) the populations of L. paracasei and B. animalis remained above 10⁶ cfu/g during the storage, whereas the population of L. acidophilus decreased dramatically during the first 4 weeks, especially the control group; (4) the microstructure was examined by scanning electron microscopy, revealing a compact and denser gel structure formed by 0.6% PWP with the presence of 0.3% pectin and 0.05% xanthan gum. In conclusion, PWP might be a proper gelation agent for the formulation of symbiotic almond yogurt alternative. PRACTICAL APPLICATION: In this study, polymerized whey protein was used as a gelation agent to formulate symbiotic almond yogurt alternatives with comparable physical texture and probiotic survivability to dairy yogurt during storage. This technology may be used for the development of plant-based fermented foods.

Biological properties of almond proteins produced by aqueous and enzyme-assisted aqueous extraction processes from almond cake

The almond cake is a protein-rich residue generated by the mechanical expression of the almond oil. The effects of the aqueous (AEP) and enzyme-assisted aqueous extraction processes (EAEP) on the biological properties of the almond cake protein were evaluated. Total phenolic content (TPC), antioxidant capacity, inhibitory effects against crucial enzymes related to metabolic syndrome, antimicrobial potential, and in vitro protein digestibility profile were assessed. EAEP provided the best results for antioxidant capacity by both ORAC (397.2 µmol TE per g) and ABTS (650.5 µmol TE per g) methods and also showed a high (~ 98%) potential for α-glucosidase inhibition. The AEP resulted in protein extracts with the highest lipase inhibition (~ 70%) in a dose-dependent way. Enzymatic kinetic analyses revealed that EAEP generated uncompetitive inhibitors against α-glucosidase, while EAEP, AEP, and HEX-AEP (used as control) generated the same kind of inhibitors against lipase. No protein extract was effective against any of the bacteria strains tested at antimicrobial assays. An in silico theoretical hydrolysis of amandin subunits corroborated with the results found for antioxidant capacity, enzyme inhibitory experiments, and antimicrobial activity. Digestibility results indicated that the digestive proteases used were efficient in hydrolyzing almond proteins, regardless of the extraction applied and that HEX-AEP presented the highest digestibility (85%). In summary, EAEP and AEP skim proteins have the potential to be used as a nutraceutical ingredient. The biological properties observed in these extracts could help mitigate the development of metabolic syndrome where EAEP and AEP skim proteins could be potentially used as a prophylactic therapy for diabetes and obesity, respectively.

A One-Pot Ultrasound-Assisted Almond Skin Separation/Polyphenols Extraction and its Effects on Structure, Polyphenols, Lipids, and Proteins Quality

Almond skin is an important by-product in the almond processing industry, rich in potentially health-promoting phenolic compounds. The objective of this present study is to separate the skin from the almond and extract its polyphenol contents using Ultrasound-Assisted Extraction (UAE) at room temperature. Optimization was performed according to a two-variable central composite design (CCD), and the optimum combination of ultrasonic intensity and extraction temperature was obtained through multi-response optimization: ultrasonic intensity (UI), 9.47 W.cm−2; and temperature, 20 °C for an extraction time of 20 min. Under the above-mentioned conditions, total phenolic content was 258% higher with UAE than silent experiment. Mathematic modelling and microscopic investigations were achieved to enable understanding physical and structural effects of ultrasound on almond skins and comprehension of the mechanism behind the enhancement of mass transfer phenomena. Scanning Electron Microscopy (SEM) showed different acoustic cavitation impacts including fragmentation, sonoporation, and erosion. Extracts were analyzed by ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), identifying a combination of flavanols, flavanones and non-flavonoids. UAE shows no negative effect on almond proteins and lipids when compared to natural almonds (NS).

Growth and digestive enzyme activities of rohu labeo rohita fed diets containing macrophytes and almond oil-cake

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Rohu were fed with almond oil-cake/ duckweed/ water fern and fishmeal blend diets.

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Highest growth was found in duckweed-based diet fed rohu.

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Duckweed is a rich source of amino acids for rohu.

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Feed composition influenced amylase, protease and lipase activities.

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Duckweed helped to replace 300 g/kg dietary fishmeal without affecting growth.

The impact of plant-based diets on the digestive physiology of rohu Labeo rohita fingerlings (10.66 ± 0.53 g) was evaluated. A diet with all protein supplied by fishmeal was included as a control (F). Four test diets containing 300 g/kg protein were formulated using the following plant ingredients and fishmeal in a 1:1 blend: almond oil-cake Terminalia catappa (FTC), duckweed Lemna minor (FLM), water fern Salvania molesta (FSM) and combination of these three ingredients (FTCLMSM). The final body weight and specific growth rate were significantly higher in rohu fed diet FLM compared to the other treatments. Significantly lower feed conversion ratio in rohu fed diet FLM showed that diet was utilized efficiently in this feeding regime compared to the other diets. The composition of diets also influenced the digestive enzyme activities of the fish. Thus, amylase, trypsin and chymotrypsin activities were significantly higher in rohu fed diet FLM compared to the rohu fed the other diets. Protease activity was significantly higher in rohu fed diets FTC and F and lipase activity was significantly higher in rohu fed diet FTC compared to the rohu fed the other diets. The inclusion of raw duckweed in feed replaced 300 g/kg of dietary fishmeal without affecting growth.

Almonds (Prunus Dulcis Mill. D. A. Webb): A Source of Nutrients and Health-Promoting Compounds

Almonds (Prunus dulcis Miller D. A. Webb (the almond or sweet almond)), from the Rosaceae family, have long been known as a source of essential nutrients; nowadays, they are in demand as a healthy food with increasing popularity for the general population and producers. Studies on the composition and characterization of almond macro- and micronutrients have shown that the nut has many nutritious ingredients such as fatty acids, lipids, amino acids, proteins, carbohydrates, vitamins and minerals, as well as secondary metabolites. However, several factors affect the nutritional quality of almonds, including genetic and environmental factors. Therefore, investigations evaluating the effects of different factors on the quality of almonds were also included. In epidemiological studies, the consumption of almonds has been associated with several therapeutically and protective health benefits. Clinical studies have verified the modulatory effects on serum glucose, lipid and uric acid levels, the regulatory role on body weight, and protective effects against diabetes, obesity, metabolic syndrome and cardiovascular diseases. Moreover, recent researchers have also confirmed the prebiotic potential of almonds. The present review was carried out to emphasize the importance of almonds as a healthy food and source of beneficial constituents for human health, and to assess the factors affecting the quality of the almond kernel. Electronic databases including PubMed, Scopus, Web of Science and SciFinder were used to investigate previously published articles on almonds in terms of components and bioactivity potentials with a particular focus on clinical trials.

Health issues and technological aspects of plant-based alternative milk

A growing number of consumers opt for plant-based milk substitutes for medical reasons, like cow's milk protein allergy (CMPA), lactose intolerance (LI), or as a lifestyle choice. Plant-based milk substitutes, or plant extracts, are water-soluble extracts of legumes, oilseeds, cereals or pseudocereals that resemble bovine milk in appearance. It is produced by reducing the size of the raw material, extracted in water and subsequently homogenized, being an alternative to cow's milk. They are considered cow's milk replacers due to similar chemical composition and can also be used as a substitute for direct use or in some animal milk-based preparations. On the other hand, these substitutes exhibit different sensory characteristics, stability and nutritional composition from cow's milk. They are manufactured by extracting the raw material in water, separating the liquid, and formulating the final product. Others process like homogenization and thermal treatments are indispensable to improve the suspension and microbiological stabilities of the final product so that can be consumed. However new and advanced non-thermal processing technologies such as ultra-high pressure homogenization and pulsed electric field processing are being researched for tackling the problems related to increase of shelf life, emulsion stability, nutritional completeness and sensory acceptability without the use of high temperatures. Some pre-treatments such as peeling, bleaching or soaking can be performed on the raw material in order to improve the final product. The nutritional properties are influenced by the plant source, processing, and fortification. The addition of other ingredients as sugar, oil and flavorings is done to the plant-based milk substitute to make them more palatable and be more acceptable to consumers. Thus, the aim is to review the main reasons for the consumption of plant-based milk substitute as well as the raw materials used and the technological aspects of its production.

Characterization of physico-chemical and bioactive properties of oils of some important almond cultivars by cold press and soxhlet extraction

The oleic acid composition of almonds oils expressed by cold press varied from 73.56% in Cristomorto cultivar to 76.59% in Tuono while oleic acid in oils extracted by soxhlet method ranged from 71.86% in Cristomorto and 75.63% in Tuono cultivars. Also, oil from cold press extraction contained 19.51% and 21.86% linoleic acid for Ferragnes and Tuono almond cultivars, respectively, while 18.74 and 20.51% linoleic acid was recorded in Soxhlet extracted oil from Ferragnes and Tuono almonds, respectively. In addition, α-tocopherol contents of the oil samples varied significantly (p < 0.05) from 14.18 to 16.86 mg/100 g in Tuono and 15.71-17.96 mg/100 g in Ferragnes for cold-press and soxhlet extracted oils, respectively. β-Sitosterol composition of the oil obtained by cold press ranged from 157.94 (Tuono) and 171.68 mg/100 g (Cristomorto) while β-sitosterol content varied from 148.91 (Tuono) and 159.68 mg/100 g (Cristomorto) for oil extracted by Soxhlet method.

Determination of the protein quality of almonds (Prunus dulcis L.) as assessed by in vitro and in vivo methodologies

Almonds (Prunus dulcis), such as all nuts, are positioned within the protein foods grouping within the current U.S. Dietary Guidelines. The ability to make claims related to the protein content of almonds, within the United States, requires substantiation via the use of the Protein Digestibility-Corrected Amino Acid Score (PDCAAS). The present study was designed to provide current estimates of PDCAAS, using both in vivo and in vitro assays, of key almond varietals from the 2017 California harvest. Additionally, historical protein and amino acid composition data on 73 separate analyses, performed from 2000 to 2014, were analyzed. Amino acid analysis confirmed lysine as the first-limiting amino acid, generating amino acid scores of 0.53, 0.52, 0.49, and 0.56 for Butte, Independence, Monterey, and Nonpareil varietals, respectively. True fecal protein digestibility coefficients ranged from 85.7% to 89.9% yielding PDCAAS values of 44.3-47.8, being highest for Nonpareil. Similar, albeit lower, results were obtained from the in vitro assessment protocol. Analysis of the historical data again positioned lysine as the limiting amino acid and yielded information on the natural variability present within the protein and amino acid profiles of almonds. Comparison of the 2017 AA profile, averaged across almond varietals, to the historical data provided strong evidence of persistence of amino acid composition and indices of protein quality over time.

Effects of almond, dried grape and dried cranberry consumption on endurance exercise performance, recovery and psychomotor speed: protocol of a randomised controlled trial

Background

Foods rich in nutrients, such as nitrate, nitrite, L-arginine and polyphenols, can promote the synthesis of nitric oxide (NO), which may induce ergogenic effects on endurance exercise performance. Thus, consuming foods rich in these components, such as almonds, dried grapes and dried cranberries (AGC), may improve athletic performance. Additionally, the antioxidant properties of these foods may reduce oxidative damage induced by intense exercise, thus improving recovery and reducing fatigue from strenuous physical training. Improvements in NO synthesis may also promote cerebral blood flow, which may improve cognitive function.

Methods and analysis

Ninety-six trained male cyclists or triathletes will be randomised to consume ~2550 kJ of either a mixture of AGC or a comparator snack food (oat bar) for 4 weeks during an overreaching endurance training protocol comprised of a 2-week heavy training phase, followed by a 2-week taper. The primary outcome is endurance exercise performance (5 min time-trial performance) and secondary outcomes include markers of NO synthesis (plasma and urinary nitrites and nitrates), muscle damage (serum creatine kinase and lactate dehydrogenase), oxidative stress (F2-isoprostanes), endurance exercise function (exercise efficiency, submaximal oxygen consumption and substrate utilisation), markers of internal training load (subjective well-being, rating of perceived exertion, maximal rate of heart rate increase and peak heart rate) and psychomotor speed (choice reaction time).

Conclusion

This study will evaluate whether consuming AGC improves endurance exercise performance, recovery and psychomotor speed across an endurance training programme, and evaluate the mechanisms responsible for any improvement.

Trial registration number

ACTRN12618000360213.

Optimization of ultrasound parameters and its effect on the properties of the activity of beta-glucosidase in apricot kernels

In this paper, ultrasound was used as an auxiliary tool to activate the activity of beta-glucosidase (beta-GC) in apricot kernels, and its parameters were optimized to evaluate the effects on the beta-GC activity with the response surface methodology (RSM), variables including ultrasonic time, temperature, power and frequency. The results indicate that the obtained quadratic regression model could simulate the actual conditions, and the optimum conditions were as follows: exposure time of 31 min, temperature 50 °C, power 225 W and frequency 28 kHz, and the activity of beta-GC achieved 3.64 × 105 U/g·apricot kernel (dry weight), having an increase of 34.67% compared to the untreated beta-GC. In addition, the changes of the beta-GC properties demonstrated that ultrasound did improve the activity of beta-GC by influencing the beta-GC's properties of fluorescence, circular dichroism, thermal property, etc. All these results would contribute to understand the mechanism of the rapid debitterizing of apricot kernels accelerated by ultrasound.

Review: Optimizing ruminant conversion of feed protein to human food protein

Ruminant livestock have the ability to produce high-quality human food from feedstuffs of little or no value for humans. Balanced essential amino acid composition of meat and milk from ruminants makes those protein sources valuable adjuncts to human diets. It is anticipated that there will be increasing demand for ruminant proteins in the future. Increasing productivity per animal dilutes out the nutritional and environmental costs of maintenance and rearing dairy animals up to production. A number of nutritional strategies improve production per animal such as ration balancing in smallholder operations and small grain supplements to ruminants fed high-forage diets. Greenhouse gas emission intensity is reduced by increased productivity per animal; recent research has developed at least one effective inhibitor of methane production in the rumen. There is widespread over-feeding of protein to dairy cattle; milk and component yields can be maintained, and sometimes even increased, at lower protein intake. Group feeding dairy cows according to production and feeding diets higher in rumen-undegraded protein can improve milk and protein yield. Supplementing rumen-protected essential amino acids will also improve N efficiency in some cases. Better N utilization reduces urinary N, which is the most environmentally unstable form of excretory N. Employing nutritional models to more accurately meet animal requirements improves nutrient efficiency. Although smallholder enterprises, which are concentrated in tropical and semi-tropical regions of developing countries, are subject to different economic pressures, nutritional biology is similar at all production levels. Rather than milk volume, nutritional strategies should maximize milk component yield, which is proportional to market value as well as food value when milk nutrients are consumed directly by farmers and their families. Moving away from Holsteins toward smaller breeds such as Jerseys, Holstein-Jersey crosses or locally adapted breeds (e.g. Vechur) would also reduce lactose production and improve metabolic, environmental and economic efficiencies. Forages containing condensed tannins or polyphenol oxidase enzymes have reduced rumen protein degradation; ruminants capture this protein more efficiently for meat and milk. Although these forages generally have lower yields and persistence, genetic modification would allow insertion of these traits into more widely cultivated forages. Ruminants will retain their niches because of their ability to produce valuable human food from low value feedstuffs. Employing these emerging strategies will allow improved productive efficiency of ruminants in both developing and developed countries.

Past, present and future: The strength of plant-based dairy substitutes based on gluten-free raw materials

Plant-based foods are gaining popularity and the market is developing fast. This trend is based on several factors, like the change of lifestyle, interest in alternative diets, and the increasing awareness about sustainable production of food and especially proteins. Plant-based dairy substitutes can serve as an option to traditional food products, meeting many of these interests. However, the market is in its infancy and needs to progress. Trends show, that the market will change from being focused on mainly soya, almond and rice-based products, due to their unsustainable farming, and nutritional concerns, like genetic modification and low protein content. The market is likely to shift towards alternative plants to meet consumers' needs and desire for healthy, flavourful and intriguing products. In this regard, the aspect of allergy-free, like gluten-free products gain in importance. Research studies are approaching the nutritional quality of plant-based dairy substitutes, such as improving the protein quality and glycaemic properties. Furthermore, the application of these products or plant proteins as functional ingredients or substitutes for cow's milk in dairy products like cheese and yoghurt are disseminated. However, there is still a need for much more diversified studies in order to overcome stability, textural, nutritional and sensory problems.

Beyond the Cholesterol-Lowering Effect of Soy Protein: A Review of the Effects of Dietary Soy and Its Constituents on Risk Factors for Cardiovascular Disease

The hypocholesterolemic effect of soy is well-documented and this has led to the regulatory approval of a health claim relating soy protein to a reduced risk of cardiovascular disease (CVD). However, soybeans contain additional components, such as isoflavones, lecithins, saponins and fiber that may improve cardiovascular health through independent mechanisms. This review summarizes the evidence on the cardiovascular benefits of non-protein soy components in relation to known CVD risk factors such as hypertension, hyperglycemia, inflammation, and obesity beyond cholesterol lowering. Overall, the available evidence suggests non-protein soy constituents improve markers of cardiovascular health; however, additional carefully designed studies are required to independently elucidate these effects. Further, work is also needed to clarify the role of isoflavone-metabolizing phenotype and gut microbiota composition on biological effect.

Evaluation of Physicochemical and Glycaemic Properties of Commercial Plant-Based Milk Substitutes

The market for plant-based dairy-type products is growing as consumers replace bovine milk in their diet, for medical reasons or as a lifestyle choice. A screening of 17 different commercial plant-based milk substitutes based on different cereals, nuts and legumes was performed, including the evaluation of physicochemical and glycaemic properties. Half of the analysed samples had low or no protein contents (<0.5 %). Only samples based on soya showed considerable high protein contents, matching the value of cow's milk (3.7 %). An in-vitro method was used to predict the glycaemic index. In general, the glycaemic index values ranged from 47 for bovine milk to 64 (almond-based) and up to 100 for rice-based samples. Most of the plant-based milk substitutes were highly unstable with separation rates up to 54.39 %/h. This study demonstrated that nutritional and physicochemical properties of plant-based milk substitutes are strongly dependent on the plant source, processing and fortification. Most products showed low nutritional qualities. Therefore, consumer awareness is important when plant-based milk substitutes are used as an alternative to cow's milk in the diet.

Effect of high pressure processing on dispersive and aggregative properties of almond milk

BACKGROUND

A study was conducted to investigate the impact of high pressure (450 and 600 MPa at 30 °C) and thermal (72, 85 and 99 °C at 0.1 MPa) treatments on dispersive and aggregative characteristics of almond milk. Experiments were conducted using a kinetic pressure testing unit and water bath. Particle size distribution, microstructure, UV absorption spectra, pH and color changes of processed and unprocessed samples were analyzed.

RESULTS

Raw almond milk represented the mono model particle size distribution with average particle diameters of 2 to 3 µm. Thermal or pressure treatment of almond milk shifted the particle size distribution towards right and increased particle size by five- to six-fold. Micrographs confirmed that both the treatments increased particle size due to aggregation of macromolecules. Pressure treatment produced relatively more and larger aggregates than those produced by heat treated samples. The apparent aggregation rate constant for 450 MPa and 600 MPa processed samples were k450MPa,30°C  = 0.0058 s(-1) and k600MPa,30°C  = 0.0095 s(-1) respectively.

CONCLUSIONS

This study showed that dispersive and aggregative properties of high pressure and heat-treated almond milk were different due to differences in protein denaturation, particles coagulation and aggregates morphological characteristics. Knowledge gained from the study will help food processors to formulate novel plant-based beverages treated with high pressure. © 2015 Society of Chemical Industry.

Antioxidant capacity of hydrolyzed protein fractions obtained from an under-explored seed protein: Gingerbread plum (Neocarya macrophylla)

The antioxidant capacity of gingerbread plum kernel protein fraction (albumin, globulin and glutelin) hydrolysates (GPKH) was studied. Gingerbread plum kernel protein fractions were hydrolyzed through a combined action of two digestive enzymes (pespsin and trypsin). The hydrolyzed fractions were subjected to antioxidant test via several chemical assays such as: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, hydroxyl radical-scavenging activity, reducing power and metal chelating activity. Total phenolic contents, amino acid composition and molecular weight distribution were also evaluated. The glutelin fraction hydrolysate showed the strongest antioxidative activity throughout the entire investigation: 79.09, 58.81, 52.08 % and 40.7 μg/mL GAE for DPPH, hydroxyl radical, chelating activity and total phenolics respectively. GPKH possess a molecular weight ranging from 300 to 4000 Da and also showed much more high reducing power than some common standards such as BHA and α-tocopherol indicating that, hydrolysates derived from gingerbread plum kernel protein could be a new antioxidants source.

Nutritional value and volatile compounds of black cherry (Prunus serotina) seeds

Prunus serotina (black cherry), commonly known in Mexico as capulín, is used in Mexican traditional medicine for the treatment of cardiovascular, respiratory, and gastrointestinal diseases. Particularly, P. serotina seeds, consumed in Mexico as snacks, are used for treating cough. In the present study, nutritional and volatile analyses of black cherry seeds were carried out to determine their nutraceutical potential. Proximate analysis indicated that P. serotina raw and toasted seeds contain mostly fat, followed by protein, fiber, carbohydrates, and ash. The potassium content in black cherry raw and toasted seeds is high, and their protein digestibility-corrected amino acid scores suggest that they might represent a complementary source of proteins. Solid phase microextraction and gas chromatography/flame ionization detection/mass spectrometry analysis allowed identification of 59 and 99 volatile compounds in the raw and toasted seeds, respectively. The major volatile compounds identified in raw and toasted seeds were 2,3-butanediol and benzaldehyde, which contribute to the flavor and odor of the toasted seeds. Moreover, it has been previously demonstrated that benzaldehyde possesses a significant vasodilator effect, therefore, the presence of this compound along with oleic, linoleic, and α-eleostearic fatty acids indicate that black cherry seeds consumption might have beneficial effects on the cardiovascular system.

Phytoprostanes in almonds: identification, quantification, and impact of cultivar and type of cultivation

The phytoprostane profile in 11 almonds cvs varied greatly according to the genotype and several factors (agricultural system conventional or ecological and irrigation).

Evaluation of seasonal antioxidant activity and total phenolic compounds in stems and leaves of some almond (Prunus amygdalus L.) varieties

BACKGROUND

This study aimed to determine the seasonal changes of total antioxidant activity and phenolic compounds in samples taken from leaves (April, July, October) and stems (April, July, October, January) of some almond (Prunus amygdalus L.) varieties (Nonpareil, Ferragnes and Texas).

RESULTS

It was indicated that antioxidant activity and phenolic compounds in leaves and stems of Nonpareil, Ferragnes and Texas showed seasonal differences. Antioxidant activity IC50 of these varieties reached the highest value in April for leaves whereas in October for stems. The highest level of total phenolic compounds was in January for stems while in October for leaves.

CONCLUSIONS

These results showed that total antioxidant activity and phenolics in leaves and stems of almond varieties changed according to season and plant organ.

Protein quality evaluation twenty years after the introduction of the protein digestibility corrected amino acid score method

In 1989 the Joint FAO/WHO Expert Consultation on Protein Quality Evaluation recommended the use of the Protein Digestibility Corrected Amino Acid Score (PDCAAS) method for evaluating protein quality. In calculating PDCAAS, the limiting amino acid score (i.e., ratio of first limiting amino acid in a gram of target food to that in a reference protein or requirement) is multiplied by protein digestibility. The PDCAAS method has now been in use for 20 years. Research emerging during this time has provided useful data on various aspects of protein quality evaluation that has made a review of the current methods used in assessing protein quality necessary. This paper provides an overview of the use of the PDCAAS method as compared to other methods and addresses some of the key challenges that remain in regards to protein quality evaluation. Furthermore, specific factors influencing protein quality including the effects of processing conditions and preparation methods are presented. Protein quality evaluation methods and recommended protein intakes currently used in different countries vis-à-vis the WHO/FAO/UNU standards are further provided. As foods are frequently consumed in complement with other foods, the significance of the PDCAAS of single protein sources may not be evident, thus, protein quality of some key food groups and challenges surrounding the calculation of the amino acid score for dietary protein mixtures are further discussed. As results from new research emerge, recommendations may need to be updated or revised to maintain relevance of methods used in calculating protein quality.