Quality Of Almonds Research Articles

Evaluating Market Structures and Credit Services for Small Scale Almond Producers in the Samangan and Balkh Provinces, Afghanistan

The objectives of the study were to investigate market price structure, market information systems, and credit services for smallholder almond producers around the Samangan and Balkh provinces of Afghanistan. A sample of 125 almond producers were the participants of the study. The primary tool for data collection was a questionnaire conducted by face to face interviews, and the secondary data of the survey collected from various sources, (CSO, FAO reports, government publications, USAID reports, NGOs reports, journals, and websites). Data were analyzed using parametric and nonparametric statistical methods. Results of the study showed that there were significant fluctuations in the average price of different almond varieties between 2014 and 2018 period. Exporters and local traders have the most influence on price determination. According to the study on the market information; 41.6% of producers acquired market information regularly, and 58.4% of them did not receive market information regularly. The research concludes that Afghanistan has a high potential and many opportunities to produce good quality of almond not only for domestic use but also for export to neighbors and more distant countries. This will help the country to take steps towards sustainable horticulture and the improvement of a viable economy.

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.

Nutrition Quality Parameters of Almonds as Affected by Deficit Irrigation Strategies.

The influence of full irrigation, double-regulated (RDI) and sustained deficit irrigation (SDI) treatments on almond quality was assessed by analyzing different parameters: sugars, organic acids, antioxidant activity, total phenolic content (TPC), and volatile compounds. Almond quality studies for plants submitted to water stress are scarce, and it is essential to understand the biochemical responses of plants to water stress in maintaining fruit yield and quality. Citric acid, sucrose, antioxidant activity, and TPC were not affected by the application of studied deficit irrigation strategies (DI). An increase in malic acid and a decrease in glucose was observed for stressed samples (T3 and T4), while a higher number of total volatiles compounds was found for moderate RDI (T2). Using deficit irrigation strategies, the almond yield and quality was not changed, and in fact, some parameters, such as glucose and key volatile compounds, slightly increased under moderate RDI. This finding might encourage farmers to implement these strategies and contribute to sustainable agriculture.

Review of the Sensory and Chemical Characteristics of Almond ( Prunus dulcis) Flavor.

Understanding almond flavor, in terms of both sensory aspects and chemistry, is essential for processors to maintain almond quality and to correctly identify acceptable or unacceptable product. This overview of the sensory and chemical characteristics of almond flavor discusses raw and heat-processed almonds, the volatile compounds generated upon heating, the aroma qualities associated with various odorants, and the use of descriptive sensory analysis for sweet almonds. Flavor development and off-flavors in almonds due to rancidity is also explored. The review examines the existing methods used to assess common nonvolatile as well as volatile indicators of lipid oxidation in almonds and the correlation of these indicators with consumer acceptance. Recent research on the relationship among volatile profile, rancidity indicators, and consumer acceptance is presented.

Nutritional quality of almond, canarium, cashew and pistachio and their oil photooxidative stability.

Daily consumption of nuts is recommended as a part of a healthy diet as they contain protein and are rich in beneficial fatty acids and essential nutrients. The nutritional qualities of nuts are affected by their fatty acid composition and other factors such as maturity. Oil oxidative stability is important to determine nut nutritional quality in terms of fatty acid composition over storage. Therefore, this study aimed to (a) assess the nutritional quality (photooxidative stability and nutrient composition) of almond, cashew, pistachio and canarium (a newly commercialised indigenous nut); and (b) explore differences in nutrient concentrations between immature and mature canarium nuts. A decrease in polyunsaturated fats after photooxidation in almond and pistachio was observed. Canarium oil did not change following photooxidation suggesting canarium may display a long shelf life when stored appropriately. Our study indicated that almond provided over 50% of the recommended daily intake for manganese whereas canarium intake provided 50% of the recommended daily intake for iron (for males). Pistachio was richer in potassium compared with other nuts and canarium was richer in boron, iron and zinc than other nut species. Mature canarium kernels were richer in boron, iron and zinc but contained less potassium than immature canarium. Therefore, the current study recommended to store kernels in dark to decrease oil photooxidation, and maturity of canarium kernels at the harvest time was important affecting nutrient concentrations of kernels.

Rootstock effect on some quality characteristics of almond cultivars ‘Troito’, ‘Marcona’ and ‘Texas’

This study was carried out in order to determine the rootstock effect on content of oil and most abundant fatty acids (oleic acid and linoleic acid), oleic acid/linoleic acid ratio, total phenolic content (TPC) and radical-scavenging activity (RSA) of almond kernels. The experimental orchard was established in 2006 in Surduk (North Serbia). Cultivars 'Troito', 'Marcona' and 'Texas' were budded (grafted) on myrabalan plum seedlings and 'GF 677'. Results revealed significant influence of rootstock on evaluated characteristics. Except content of oleic acid and oleic acid/linoleic acid ratio all other parameters had higher values when cultivars were grafted onto myrabalan plum. As expected, significant differences were also determined among studied cultivars. Except content of linoleic acid, for all other parameters the lowest values were found in 'Marcona', while highest for 'Texas'. Obtained results can be used for improving of almond quality in agroecological conditions of Serbia.

Effect of fertigation on growth, yield and quality of almond under Kashmir conditions

An experiment was conducted for three consecutive years during 2011–12 to 2013–14 with an objective to improve growth, yield and quality of almond by fertigation. There were seven fertigation treatments laid out in randomised block design with three replications. The results revealed maximum plant height (3.67 m), TCSA of main trunk (101.22 cm2), primary, secondary and tertiary branches (20.51 cm2, 6.66 cm2 and 1.97 cm2), canopy volume (8.21m3), and nut yield (4.94 kg/tree and 5.48 t/ha), leaf nitrogen and potassium content (2.39% N and 1.41%K) with 75% RDF through fertigation (split application of N: K in the ratio of 2/3N: 1/3K at nut set to nut development and 1/3N: 2/3K at kernel filling to maturation stage(T-4). The highest fruit number (2208/tree), however, was recorded with 100% RDF through fertigation (T2). The maximum nut weight and size (2.29 g and 36.51 × 21.45 mm), kernel weight and size (1.48 g and 24.71 × 14.59 mm) were recorded with 50% RDF through fertigation (T5) treatment of almond variety Waris under Kashmir valley condition.

Effect of mango kernel starch coatings on the shelf life of almond ( Prunus dulcis ) kernels

The effect of mango kernel starch (MKS) coatings on shelf life of roasted almonds was determined. The coating formulations were prepared by gelatinizing 4% MKS in distilled water and plasticized with glycerol, sorbitol, and their 1:1 mixture (50% of starch weight; db). Lipid oxidation was evaluated by peroxide value (PV), thiobarbituric acid reactive substances (TBARS), and p-anisidine (AV) values. Results showed significant differences in coated and uncoated nuts and the rate of oxidation was significantly low in all coated samples. All coated nuts provided effective protection against oxidation compared with the control, particularly, the sorbitol coated nuts that did not show any sign of deterioration during 100 days of storage at 40 °C whereas in control rancidity appeared just after 50 days. Sensory evaluation of coated nuts also supported the chemical testing outcomes and all the coated nuts received higher scores for color, flavor, and texture than uncoated nuts. Practical applications Almonds have high commercial value and are consumed both in raw or roasted form and also added as an ingredient in many processed foods including confectionary, bakery products, ice creams, and beverages. The quality of almonds deteriorates during storage due to oxidation of its oil content that contains high proportion of oleic acids (unsaturated fatty acids) that are susceptible to oxidation. Among different renewable resources mango kernel starch is abundant but underutilized source of starch which has not been received significant attention from the researchers so far. At present, this inexpensive source of starch is usually ignored and wasted during mango processing; in spite of the fact that most of its properties are comparable to other commercial starches. Therefore, the application of edible coating based on mango kernel starch can make a significant contribution in prolonging shelf life of almonds, while developing healthy and natural foods.

Verification of radio frequency pasteurization process for in-shell almonds

Salmonella outbreaks related to consumption of raw almonds have forced nut industry to seek effective pasteurization processes. Radio frequency (RF) treatment is a potential pasteurization method for controlling Salmonella while maintaining product quality. Escherichia coli ATCC 25922 is nonpathogenic and can be used as a surrogate of pathogenic Salmonella when their thermo-tolerances are equivalent. Since thermal resistance of target pathogens can be reduced by raising water activity in dry samples, the aim of this study was to explore the application of RF treatments to control E. coli ATCC 25922 in pre-washed in-shell almonds without quality losses. A 6 kW, 27.12 MHz RF heating system was used to rapidly pasteurize 1.7 kg washed in-shell almonds together with hot air heating at 55 °C. To meet effective pasteurization requirements and maintain almond quality, the RF treatment protocol was obtained by using an electrode gap of 10.5 cm for pasteurization, 12 cm for drying, and followed by forced room air cooling in 3 cm thick samples. The results showed that the RF heating at the electrode gap of 10.5 cm for 1.5 min achieved 5-log reductions of E. coli ATCC 25922 and the followed RF drying for 8.5 min reduced the moisture content of almond shell back to 5.08% w.b. Kernel color, peroxide value, weight loss, fatty acid value and fatty acid composition of RF treated almonds met good quality standard used by almond industry. Therefore, RF treatments are an effective and rapid heating method to control Salmonella in pre-washed in-shell almonds.

Effectiveness of superheated steam for inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type 30, and Listeria monocytogenes on almonds and pistachios

This study was undertaken to evaluate the effectiveness of superheated steam (SHS) on the inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Enteritidis phage type (PT) 30 and Listeria monocytogenes on almonds and in-shell pistachios and to determine the effect of superheated steam heating on quality by measuring color and texture changes. Almonds and in-shell pistachios inoculated with four foodborne pathogens were treated with saturated steam (SS) at 100°C and SHS at 125, 150, 175, and 200°C for various times. Exposure of almonds and pistachios to SHS for 15 or 30s at 200°C achieved >5log reductions among all tested pathogens without causing significant changes in color values or texture parameters (P>0.05). For both almonds and pistachios, acid and peroxide values (PV) following SS and SHS treatment for up to 15s and 30s, respectively, were within the acceptable range (PV<1.0meq/kg). These results show that thermal application of 200°C SHS treatment for 15s and 30s did not affect the quality of almonds and pistachios, respectively. Therefore, SHS treatment is a very promising alternative technology for the tree nuts industry by improving inactivation of foodborne pathogens on almonds and pistachios while simultaneously reducing processing time.

Pollination and Plant Resources Change the Nutritional Quality of Almonds for Human Health

Insect-pollinated crops provide important nutrients for human health. Pollination, water and nutrients available to crops can influence yield, but it is not known if the nutritional value of the crop is also influenced. Almonds are an important source of critical nutrients for human health such as unsaturated fat and vitamin E. We manipulated the pollination of almond trees and the resources available to the trees, to investigate the impact on the nutritional composition of the crop. The pollination treatments were: (a) exclusion of pollinators to initiate self-pollination and (b) hand cross-pollination; the plant resource treatments were: (c) reduced water and (d) no fertilizer. In an orchard in northern California, trees were exposed to a single treatment or a combination of two (one pollination and one resource). Both the fat and vitamin E composition of the nuts were highly influenced by pollination. Lower proportions of oleic to linoleic acid, which are less desirable from both a health and commercial perspective, were produced by the self-pollinated trees. However, higher levels of vitamin E were found in the self-pollinated nuts. In some cases, combined changes in pollination and plant resources sharpened the pollination effects, even when plant resources were not influencing the nutrients as an individual treatment. This study highlights the importance of insects as providers of cross-pollination for fruit quality that can affect human health, and, for the first time, shows that other environmental factors can sharpen the effect of pollination. This contributes to an emerging field of research investigating the complexity of interactions of ecosystem services affecting the nutritional value and commercial quality of crops.

Genetic analysis for physical nut traits in almond

Almond breeding is increasingly taking into account kernel quality as a breeding objective. Although information on nut and kernel physical parameters involved in almond quality has already been compiled, the genetic control of these traits has not been studied. This genetic information would improve the efficacy of almond breeding programs. A linkage map with 56 simple-sequence repeat markers was constructed for the “Vivot” × “Blanquerna” almond population showing a wide range of variability for the physical parameters of nut and kernel. A total of 14 putative quantitative trait loci (QTLs) controlling these physical traits were detected in the current study, corresponding to six genomic regions of the eight almond linkage groups (LG). Some QTLs are colocated in the same region or shared the same molecular markers, in a manner that reflects the correlations between the physical traits, as well as with the chemical components of the almond kernel. The limit of detection values for any given trait ranged from 2.06 to 5.17, explaining between 13.0 and 44.0 % of the phenotypic variance of the trait. This new genetic information needs to be taken into account when breeding for physical traits in almond. Increases in the positive quality traits, both physical and chemical, need to be considered simultaneously whenever they are genetically independent, even if they are negatively correlated. This is the first complete genetic framework map for physical components of almond nut and kernel, with 14 putative QTLs associated with a large number of parameters controlling physical traits in almond.

Mapping quantitative trait loci for kernel composition in almond

BackgroundAlmond breeding is increasingly taking into account kernel quality as a breeding objective. Information on the parameters to be considered in evaluating almond quality, such as protein and oil content, as well as oleic acid and tocopherol concentration, has been recently compiled. The genetic control of these traits has not yet been studied in almond, although this information would improve the efficiency of almond breeding programs.ResultsA map with 56 simple sequence repeat or microsatellite (SSR) markers was constructed for an almond population showing a wide range of variability for the chemical components of the almond kernel. A total of 12 putative quantitative trait loci (QTL) controlling these chemical traits have been detected in this analysis, corresponding to seven genomic regions of the eight almond linkage groups (LG). Some QTL were clustered in the same region or shared the same molecular markers, according to the correlations already found between the chemical traits. The logarithm of the odds (LOD) values for any given trait ranged from 2.12 to 4.87, explaining from 11.0 to 33.1 % of the phenotypic variance of the trait.ConclusionsThe results produced in the study offer the opportunity to include the new genetic information in almond breeding programs. Increases in the positive traits of kernel quality may be looked for simultaneously whenever they are genetically independent, even if they are negatively correlated. We have provided the first genetic framework for the chemical components of the almond kernel, with twelve QTL in agreement with the large number of genes controlling their metabolism.

Review of Current Technologies for Reduction of Salmonella Populations on Almonds

After the 2001 and 2004 Salmonellosis outbreaks that were associated with raw almonds, ensuring the microbial safety of almonds by treating them to achieve a minimum 4-log reduction of Salmonella population became mandatory in California, the world’s largest almond producer. In this paper, we summarize potential pathways of microbial contamination during almond production and manufacturing. Furthermore, we review sanitization technologies, including chemical, thermal, and non-thermal methods, as well as proprietary systems with regard to microbial and sensory quality of almonds and compare various aspects of their use during almond processing.

The effect of X-ray irradiation on Salmonella inactivation and sensory quality of almonds and walnuts as a function of water activity

The overall goal of this study was to develop a set of process design principles for low-energy X-ray irradiation of tree nuts. Almonds and walnuts were inoculated with Salmonella Enteritidis PT30 and Salmonella Tennessee, and conditioned to four different water activities (0.23, 0.45, 0.64, and 0.84 a(w)). Thereafter, the inoculated/conditioned samples were irradiated to achieve up to a 5-log reduction in Salmonella using a pilot scale low-energy X-ray food irradiator. Greater efficacy (D(10)-value: the dose required to eliminate 90% of the microbial population) for inactivating SE PT30 and S. Tennessee was seen on the surface of almonds (0.226-0.431 kGy) than on walnuts (0.474-0.930 kGy) at all water activities. Also, the efficacy did not change monotonically with water activity. Overall, no significant difference (P>0.05) in sensory characteristics was seen between non-irradiated almonds and those irradiated to achieve a 5 log reduction in Salmonella. However, irradiating walnuts to the dose corresponding to a 5 log reduction caused a perceivable change in flavor. Post-irradiation storage tests revealed that surviving bacterial counts did not change over 120 days, regardless of nut type, Salmonella serovar, and a(w). Therefore, low-energy X-ray irradiation technology appears to be a promising non-thermal pasteurization strategy for certain types of nuts.

THE DEFINITION OF THE EUROPEAN ALMOND CORE COLLECTION

THE DEFINITION OF THE EUROPEAN ALMOND CORE COLLECTION

THERMODYNAMIC ANALYSIS OF MOISTURE ADSORPTION ISOTHERMS OF RAW AND BLANCHED ALMONDS

ABSTRACTThe equilibrium moisture content of raw and blanched almonds of California grown “Carmel” variety was determined by using static gravimetric method at 25, 35 and 45C over a range of water activities (Aw) from 0.11 to 0.97. The sorption data were fitted to the Guggenheim–Anderson–de Boer (GAB) model. The goodness of fit of the model was evaluated by standard error of estimate, mean relative percentage deviation modulus and randomness of residual, which showed good fit of the GAB equation to the experimental data. The moisture adsorption isotherms of almonds exhibited type II sigmoid shape. Thermodynamic properties such as differential enthalpy and entropy were determined from moisture adsorption data by using the Clausius–Clapeyron equation. The results showed that enthalpy–entropy compensation theory was applicable for the moisture adsorption phenomena of raw and blanched almonds. The adsorption process of almond was enthalpy‐controlled.PRACTICAL APPLICATIONSOver 80% of the world almond production is grown in California and shipped to over 90 countries around the world. When exported to distant markets in the tropical regions, the physical, chemical and microbiological changes in almonds could cause the deterioration of food products due to environmental factors. Despite the large‐scale production and export of almonds, very little information on the sorption characteristics of almond varieties grown in California can be found in the literature. Reliable information on sorption isotherms is critical to designing optimum storage and shipping conditions to ensure desired levels of almond quality at consumption. This paper presents results from a comprehensive study of the sorption characteristics of one of the most important almond varieties grown in California, namely “Carmel.”

Improving Chocolate Flavor in Poor‐Quality Cocoa Almonds by Enzymatic Treatment

This paper proposes a method to enzymatically treat poor-quality cocoa almonds (known as "slate") to ensure the formation of chocolate flavor precursors. The production of flavor precursors improves the quality of these almonds, which are usually responsible for the low quality of the liquor produced. Proteases and carboxypeptidases from different sources were tested under various conditions. The different treatments were evaluated by chemical analysis (hydrolysis efficiency) and sensory analysis of the treated material compared to good-quality cocoa almonds. The results show that it is possible, through the use of microbial enzymes, to generate the mixture of compounds that will release, after roasting, the characteristic chocolate flavor in poor-quality almonds. However, it is necessary to optimize the conditions of enzymatic treatment to obtain better results and thus establish a process that can be used for industrial purposes for manufacturing cocoa and chocolate. The basidiomycete Moniliophtora perniciosa is the causative agent of witches' broom disease (WBD) of the cocoa tree, whose seeds are the source of chocolate. It is the most important phytopathological problem of cocoa-producing areas of the American continent, and has decimated the Brazilian cocoa industry. In Bahia (Brazil), M. perniciosa was identified in 1989 and, as a consequence of its spreading, the annual production of cocoa almonds dropped from 450,000 to 90,000 tons within 12 y, reducing export values from an all-time high of about US$ 1 billion to 110 million. The high incidence of WBD incapacitates Brazil to produce enough cocoa almonds even for the internal market, leading the country to import low-quality cocoa almonds mainly from African countries. Our work proposes an enzymatic treatment to increase the quality of that cocoa almonds and, consequently, to improve the quality of the chocolate produced and consumed in the country.

Volatile composition and descriptive sensory analysis of Italian vanilla torrone

SummaryVanilla torrone is a honey‐ and almond‐based confectionery product very famous in Italy, especially during Christmas. In this study, the effects of two factors, the manufacturing company and the manufacturing season, on the volatile composition of vanilla torrone were studied. Volatile compounds in torrone samples were extracted using simultaneous distillation‐extraction and finally isolated, semi‐quantified and identified using GC‐MS. A trained panel was also used to make a descriptive analysis of torrone. Benzene derivatives and terpenes were the predominant chemical groups in torrone samples. The addition of artificial flavourings (mainly vanillin and benzaldehyde) played an important role in determining the final composition of volatiles and their concentrations. However, the amount and quality of almonds and honey and the intensity of almond toasting could also play important roles. If manufacturers want to provide a more homogeneous product to the consumers, more attention should be paid to the composition and concentrations of the flavourings added.

Characteristics of Iranian almond nuts and oils

AbstractAlmonds of nine different iranian cultivars were studied. The characteristics of almond nuts and almond oils from these cultivars were determined. They also were studied for possible deterioration of their oils during long storage time. Almond nuts from some cultivars showed significant differences. The variations found in the oil characteristics of different cultivars are not definitely due to varietal differences. The majority of these data does not agree with that found in literature. Acid and peroxide values are very low in both 3 and 12 month old samples, proving the good keeping quality of almonds with regard to their oil content.