Moisture Dependent Geometric and Mechanical Properties of Wild Pistachio (Pistacia vera L.) Nut and Kernel

In this research, wild pistachio (Pistacia vera L.) nuts and kernels were analyzed for selected geometric properties and mechanical behavior under compression loading. The average length, width and thickness arithmetic and geometric mean diameter of wild pistachio nuts at 5.83% w.b. were 13.98, 8.76, 7.25, 9.93, and 9.75 mm, while the corresponding values of kernels at 6.03% w.b. moisture content were 11.07, 5.92, 4.83, 7.21, and 6.88 mm, respectively. As the moisture content of pistachio nut increased from 5.83 to 30.73% w.b., the bulk density, apparent density and terminal velocity were found to increase from 521 to 543 kgm^?3, 809 to 829 kgm^?3, and 5.51 to 6.29 ms^?1, respectively, whereas porosity decreased from 35.14% to 34.63%. The results revealed that wild pistachio nut required higher rupture force and energy to crack wild pistachio nuts for compression along the L-axis as compared to other two axes.     

Effect of gamma irradiation on the physico‐chemical and sensory properties of raw shelled peanuts (Arachis hypogaea L.) and pistachio nuts (Pistacia vera L.)

Backround The present study evaluated the quality of raw peanuts and pistachio nuts as a function of irradiation dose in order to determine dose levels causing minimal undesirable changes to these products. Physico‐chemical (colour, peroxide value, hexanal content, fatty acid composition, volatile compounds) and sensory (colour, texture, odour, taste) properties of raw peanuts and pistachio nuts were determined after irradiation at doses up to 7 kGy. Results Results showed an eight‐ and seven‐fold increase in peroxide value and a twelve and five‐fold increase in hexanal content after irradiation at a dose of 7 kGy for peanuts and pistachio nuts, respectively. An increase was also observed in saturated fatty acids (20.51–28.28% and 15.24–24.87%) with a parallel decrease in unsaturated fatty acids (79.49–71.72% and 84.76–75.13%) for peanuts and pistachio nuts, respectively. Likewise, volatile compounds such as aldehydes, alkanes, ketones and alcohols comprising secondary oxidation products of peanut and pistachio nut lipids increased after irradiation. Pistachio nut colour parameter a* and to a lesser extent parameters, L* and b* decreased after irradiation leading to a slight but noticeable darkening in product colour while colour parameter L*, b* and a* of raw peanut remained unchanged by irradiation up to 7 kGy. Conclusion Based on sensory evaluation, peanuts and pistachio nuts become unacceptable for consumption when irradiated at doses higher than 3 kGy. Copyright © 2009 Society of Chemical Industry     

Effect of roasting on colour and volatile composition of pistachios (Pistacia vera L.)

Pistachios have been roasted following the Iranian traditional method (soaking in salty water, drying and roasting at 135 °C). Three Iranian pistachio cultivars (Ahmad Aghaei, Akbari and Kaleghouchi) were compared for their volatile compositions, colour and odour intensity. Lightness decreased in the course of roasting, which resulted from Maillard reaction. Raw pistachios had lower concentrations of most volatiles than roasted. A total of twenty‐six compounds were detected in roasted pistachios; these included aldehydes, terpenes, alcohols and only two pyrazines and one furan. These mixtures of volatiles implied that the Iranian roasting system is very soft, and samples retained most of the vegetable notes from fresh pistachios and some roasted notes were generated as well (from 2‐ethyl‐5‐methylpyrazine and 2,6‐dimethyl‐3‐ethylpyrazine). Sample from cultivar Akbari presented higher odour intensity than those by the other two cultivars, due mainly to higher concentrations of pyrazines developed during the roasting step.     

Development of a Hull-Less Pumpkin (Cucurbita pepo L.) Seed Oil Press-Cake Spread

A stable, oil-based spread rich in the omega-3 (ω-3) and omega-6 (ω-6) fatty acids was developed using a hull-less pumpkin seed (Cucurbita pepo L.) oil press-cake, a by-product of the pumpkin oil pressing process, along with cold-pressed hemp oil. Response surface methodology (RSM) was applied to investigate the effects of two factors, as the formulation's compositional variables: a commercial stabilizer (X(1) ) and cold-pressed hemp oil (X(2) ) added to the pumpkin seed oil press-cake in the spread formulations. A central composite, 2-factorial experimental design on 5 levels was used to optimize the spreads where model responses were ω-3 fatty acids content, spreadability (hardness), oil separation, and sensory evaluation. The selected responses were significantly affected by both variables (P < 0.05). The spreads resembled commercial peanut butter, both in appearance, texture and spreadability; were a source of ω-3 fatty acids and with no visual oil separation after 1 mo of storage. An optimum spread was produced using 1.25% (w/w) of stabilizer and 80% of hemp oil (w/w, of the total added oil) which had 0.97 g of ω-3 fatty acids per serving size; penetration depth of 68.4 mm; oil separation of 9.2% after 3 mo of storage; and a sensory score of 17.5. Practical Application: A use of by-products generated from different food processing technologies, where the edible waste is successfully incorporated as a value-added ingredient, has become a very important area of research to support global sustainability efforts. This study contributes to the knowledge of a product design process for oil-based spread development, where oil press-cake, a by-product of the oil pressing process of the naked pumpkin seeds, was used and where results have demonstrated that a new product can be successfully developed and potentially manufactured as a functional food.     

Panelist Texture Preferences Affect Sensory Evaluation of Green Bean Cultivars (Phaseohs vulgaris L.)

The effects of textural preferences on sensory intensity and hedonic scores assigned by consumer panelists (50 preferred “soft” and 38 “crisp” beans) to green beans (Phaseolus vulgaris L.) of two cultivars cooked by 2 methods were studied. Boiled and 'Strike’beans were rated lighter than steamed and‘Mustang’beans.‘Mustang’beans were scored more acceptable for color, flavor, and overall likability. Soft textural preference panelists liked steamed beans less than boiled beans for texture, flavor, and overall likability. Hedonic scores assigned by panelists of crisp textural preference did not differ by preparation method. Selecting panelists without considering textural preferences may influence hedonic but not intensity scores.     

Pistachio (Pistacia vera var Kerman) from Argentinean cultivars. A natural product with potential to improve human health

The chemical profile, mineral content as well as antioxidant activities of three cultivars of Pistacia vera cv Kerman were investigated. The total phenolic (TP) content flavonoids (FT) and anthocyanins (TA) were measured. Additionally, the profile of polyphenols was analyzed. A slight, not significant, increment was observed in TP content between cultivars with different age (5, 9 and 11 years old). The 9 years old cultivar showed the highest FL value, while the 11 years old cultivar had the higher TA content. Main polyphenols were separated by HPLC and identified by electrospray ionization (ESI) coupled to quadrupole-time of flight mass spectrometry (LC–ESI–QTOF–MS). Gallic acid and (+)-catechin were present in higher amounts. The presence of myricetin, isoquercitrin and a dimer of procyanidin are reported for the first time in pistachio. Additionally, K, Ca and Mg were found in high proportion. The highest antioxidant capacity was measured in the 11 years old pistachio cultivar. This work presents the first evidence that Pistacia vera cv Kerman from Argentinean cultivars could be considered as a functional food or ingredient in a diet, with potential to improve human health.     

Development and characterisation of a sugar‐free milk‐based dessert formulation with fig (Ficus carica L.) and carboxymethylcellulose

The objective of this study was to develop an optimum formula for ‘Shir Anjir’, an Iranian dessert containing milk, dried fig (13, 16.5, 20%) and carboxymethylcellulose (CMC) (0, 0.35, 0.7%) with no added sugar. Apparent viscosity, flow behaviour indices, pH, acidity (% lactic acid), total solid and colour parameters were compared. Sensory tests were performed to evaluate degree of liking of colour, appearance, taste, texture, mouthfeel and general acceptance. Figs and CMC influenced the dessert's characteristics. The most popular formula contained milk, 16.5% figs and 0.7% CMC and had an apparent viscosity of 3.78 Pa·s at 5 °C, exhibiting a shear‐thinning behaviour.     

Effect of chronic consumption of pistachios (Pistacia vera L.) on glucose metabolism in pre-diabetics and type 2 diabetics: A systematic review

Pistachio is a nut with high polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA), polyphenols and carotenoids content, and the synergism between these compounds appears to affect glucose metabolism. In this systematic review we analyzed studies in which the effect of chronic consumption of pistachio on markers of glucose metabolism was evaluated in pre-diabetic and type 2 diabetics. We used the PubMed, Scopus, Cochrane and Lilacs databases. The research terms used were pistachio, pre-diabetes, type 2 diabetes mellitus, insulin resistance, blood glucose, hyperglycemia and glycated hemoglobin (HbA1c). Four articles were selected, of which three tested the intake of 50 to 57 g of pistachio/day and one 20% of the daily caloric intake, for a period of 1 to 4 months. Studies reported a decrease in fasting blood glucose, insulinemia, HOMA-IR, and fructosamine, but no change in HbA1c. Lower concentrations of miR-192 and miR-375 were also found, which correlated positively with HOMA-IR. The synergism between PUFA, MUFA, polyphenols and carotenoids present in pistachios can modulate specific miRNA, increasing insulin sensitivity through the PI3K-AKT signaling pathway. This modulation can be used as a tool to monitor the response to interventions, favoring the prevention and treatment of complications related to diabetes.     

Development and characterisation of functional cocoa (Theobroma cacao L.)-based edible films

The aim of this study was to develop functional edible films containing cocoa (Theobroma cacao L.) powder extract using alginate, pectin and chitosan in combination with proteins (whey protein isolate, soya and hemp protein). The films were examined for their physico-chemical (dry matter content, colour, thickness), mechanical (elongation at break (EAB)), bioactive (the content of total polyphenols (TPC), flavan-3-ols (F3olC), antioxidant capacity (AC)) and sensory properties. The plain alginate film exhibited the highest EAB (29.1%). The highest TPC and F3olC were determined in plain alginate (29 mg GAE/g and 2.75 mg (+)-catechin/g) and pectin (29 mg GAE/g and 2.25 mg (+)-catechin/g) films. The addition of proteins resulted in prolonged release of polyphenols and enhanced functional properties; however, the formation of protein–polyphenol complexes caused slight alterations in the bioactive composition of the films. The obtained results indicate a high potential of the developed films as functional, biodegradable form of active food packaging.     

棕榈油与红棕油替代牛油对传统火锅底料风味物质布料吸附特性的影响

针对市售传统牛油火锅底料风味易被衣物吸附的问题，以红棕油、棕榈油、棕榈油与牛油混合油(棕榈油与牛油比例分别为7∶3、1∶1及3∶7)及牛油所制得的6种火锅底料为原料，模拟火锅食用时布料吸附火锅底料风味物质的过程，对火锅底料进行感官评价，并通过感官评价、电子鼻分析和全二维气相色谱质谱联用仪(GC×GC-MS)结合相对气味活度值(ROAV)法对火锅底料风味物质的布料吸附特性进行研究，探究红棕油和棕榈油替代牛油对传统火锅底料风味物质布料吸附特性的影响。结果表明：添加红棕油和棕榈油不会影响火锅底料的感官；吸附红棕油或棕榈油火锅底料风味物质的布料感官评分较高，且在电子鼻W5S感应器的响应值较低；GC×GC-MS检测结果表明布料吸附不同油脂制备的火锅底料的风味物质具有较大差异；ROAV结果表明醇类及醛类物质贡献最大，布料吸附6种火锅底料风味物质的共有关键风味成分(ROAV≥1)有α-松油醇、芳樟醇、正辛醛、壬醛、癸醛、反式-2-壬醛，相较于牛油，红棕油及棕榈油能减少布料吸附的风味物质。综上，红棕油或棕榈油火锅底料感官好，其风味物质的布料吸附性较低，可以取代牛油火锅底料。     

LIQUID HOLDING CAPACITY AND INSTRUMENTAL AND SENSORY TEXTURE PROPERTIES OF HERRING (CLUPEA HARENGUS L.) RELATED TO BIOLOGICAL AND CHEMICAL PARAMETERS

Instrumental texture measurements done on raw herring fillets only partly describe the sensory texture of marinated herring fillets. Sensory texture parameters of marinated fillets were related to instrumental texture measurements of raw fillets by three different data analysis approaches. Uniaxial compression measurements were used as a single parameter, as compression curves or fitted to polynomials. Data from all three methods were related to sensory firmness (r = 0.310–0.366, P < 0.05). Elasticity could be predicted from the maximum compression force (r = 0.181, P < 0.05). The compression curve contained information correlating with all the measured sensory texture parameters (r = 0.102–0.310, P < 0.05), while the fitted polynomials, in addition to firmness, could predict fatty mouthfeel (r = 0.201, P < 0.05). The most information about the sensory texture was obtained from the compression curves. This study shows that the texture properties of herring are highly intercorrelated and can be regarded as a multivariate complex of parameters. The liquid holding capacity (LHC), defined as the moisture held after a low centrifuge speed expressible moisture measurement, and the texture of herring are influenced by a variety of factors, e.g., spawning time of year, gonad maturity, body size, age and lipid content (P < 0.05). Increases in body weight, age and lipid content are intercorrelated and result in marinated fillets being more firm, elastic, juicy and fatty. Decreases in these factors will give marinated fillets that are perceived to be gritty and with low intensities of firmness, elasticity, juiciness and fatty mouthfeel.