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The use of regression with life-data is helpful to observe whether one or more factors affect the failure time (spoilage) of a product, obtaining a model that predicts the time to fail (TTF). TTF models link kinetic (lag time) and probabilistic (growth /no-growth prediction) models for selected formulation/storage conditions. Our objective was to assess the individual and combined effects of pH, a w , and the incorporation of potassium sorbate (KS) or sodium benzoate (BNa) at selected concentrations on the microbial stability of peach nectar during storage at 25°C, in order to model and predict TTF. Peach nectars were formulated with 40% fruit pulp and the necessary sucrose syrup and citric acid to attain a w 0.96, 0.97, or 0.98 and pH 3.0, 3.5, or 4.0; while 0, 500, or 1000ppm of KS or BNa were added. Nectars were stored for 180 days in glass jars at 25°C, and periodically analyzed (standard plate as well as yeast and mould counts). The experimental design and analyses were replicated three times. Storage times that revealed microbial populations higher than 10 4 CFU/mL and signs of spoilage were registered to model TTF by survival analysis. From the 54 combinations tested, 9 formulations (without antimicrobials) exhibited early spoilage (<5 days). For the combinations formulated with 500ppm of BNa, spoilage was detected after 30 days; much longer spoilage times were observed for nectars with 1000ppm of KS or BNa. In general, KS was more effective than BNa in delaying spoilage when 1000ppm were added. TTF models included individual and interaction effects of the evaluated factors and revealed good agreement among experimental and predicted data (R 2 >0.90). Survival analysis through TTF models can be used to predict spoilage time under specific factor combinations or to select factor levels for a specific shelf-life of peach nectars. [ABSTRACT FROM AUTHOR]

Regime (direction, amount, rate, and pattern) of change in aroma active compounds was quantified as a function of four pulsed electric field (PEF) treatment times, three fruits, and 10 physical and eight sensory properties using the best-fit multiple linear regression (MLR) models. The PEF treatment times did not deteriorate 94% of the sensory properties and 70% of the physical properties and significantly change 57% of a total of 73 aroma active compounds detected for sour cherry juice, and apricot and peach nectars. The best performing MLR models belonged to 1-methyl-4-prop-1-en-2-ylcyclohexene as a function of fruit type, treatment time, and titratable acidity (= 49 mg/L; R adj 2 = 95.7%; R cv 2 = 94.9%) and to 2-[(2S,5S)-5-ethenyl-5-methyloxolan-2-yl]propan-2-ol as a function of fruit type, and treatment time (SE = 157 mg/L; R adj 2 = 98.2%; R cv 2 = 98.0%), respectively ( n = 48; p < 0.001). Industrial relevance Pulsed electric field (PEF) is one of the leading nonthermal food technologies especiallyfor processing of high acid low viscosity foods with satisfactory quality and microbial inactivation. It was shown in this study that PEF with different treatment times can successfully be applied in the pasteurization of sour cherry juice, and apricot and peach nectars with minimum loss of aroma active compounds and sensory and physical properties. Both PEF processing conditions and results can be used as a guide to determine PEF processing parameters for industrial scale processing of juices/nectars. [ABSTRACT FROM AUTHOR]

Effects of pulsed electric field (PEF) processing on 28 aroma active compounds, and four physical and eight sensory properties of peach nectar were explored using the best-fit multiple linear regression (MLR) models and Monte Carlo simulations as a function of the treatment times of 0, 66, 131, and 210 μs. The PEF treatment time of 131 μs on average led consistently to the least loss of most compounds. Significantly enhanced or no significant changes in the sensory properties were found as a function of the PEF treatment times. The most influential sensory predictor of the 28 MLR models was flavour, while the aroma compound most influential on the sensory properties of aftertaste, flavour, sweetness, and overall acceptance was octadecanoic acid. Monte Carlo simulations were used for the probabilistic assessments of stochastic variability and uncertainty associated with aroma active compounds of PEF-treated peach nectar. [ABSTRACT FROM AUTHOR]

Enterolobium cyclocarpum, (caro-caro), especie ampliamente diseminada en Venezuela, produce goma con alto rendimiento. Se estudió el comportamiento de este hidrocoloide como aditivo en la preparación de néctares de durazno. El ensayo consistió en seis tratamientos, utilizando diferentes concentraciones de la goma (0,20; 0,30; 0,50; 0,70; 1%), y un tratamiento control (sin goma). Las características físico-químicas (acidez, pH, sólidos solubles, viscosidad, estabilidad) y las propiedades sensoriales del producto elaborado se evaluaron. Se aplicó un diseño de bloques al azar con seis repeticiones. Los resultados mostraron que la viscosidad exhibida por los néctares elaborados a la mayor concentración (1%), se incrementó significativamente (PEnterolobium cyclocarpum, (caro-caro), species widely disseminated in Venezuela, produces gum with high yield. It was studied the behavior of this hydrocolloid as additive in the preparation of peach nectar. It was carried out six treatments using different gum concentration (0.20; 0.30; 0.50; 0.70; 1%) wich were compared with a treatment without gum. There were measured physicochemical characteristics (acidity, pH, soluble solids, viscosity and stability) and sensorial attributes of the product. A random desing of blocks with six repetitions was applied. The results showed that the viscosity exhibited by the product obtained, using the highest gum concentration (1%) increased significatively (P

The aim of this study was to make a physicochemical and sensorial evaluation of five types of peach nectar, given for consumption by producers in Dâmbovița County. Peach nectars are one of the most consumed types of nectar, because peaches are native fruits with special sensorial qualities. Quality Standards of nectars in Romania impose legal limits for: soluble solids, titratable acidity, vitamin C, insoluble substances, foreign bodies and other analyzes were performed according to the methods prescribed by CODEX ALIMENTARIUS. In accordance with Standards and CODEX ALIMENTARIUS, peach nectar pH should be maximum 4 pH units, relative density of about 1,0576, soluble solids content at least 11%, titratable acidity of not less than 0,4%, the content of vitamin C at least 10 mg ascorbic acid/100ml, the content of insoluble substances maximum 0,5g/100cm³ and foreign bodies are not allowed. Comparative analysis of the results was in relation with Technical Standards for noncarbonated soft drinks industry. [ABSTRACT FROM AUTHOR]

Processed food products present high energy intensity, along with a large amount of food losses and waste. The recovery of residual biomass as integrated renewable energy source could represent an interesting option for the substitution of fossil energy, contributing to the transition of agro-food sector towards a low-carbon economy. Two scenarios were compared, in order to evaluate the impacts of a fossil fuel-based food chain and the potential benefits of the integration of bioenergy production, using peach nectar as case study. In the first scenario, peach nectar is produced, distributed and consumed using fossil energy, while residuals are wasted. In the second scenario, byproducts from the nectar chain are used to produce bioenergy from combustion or anaerobic digestion, which is then consumed to substitute electricity and heat. A comparative life cycle assessment (LCA) based on the same functional unit was performed. Main results show that, in the conventional scenario, most of the damage derives from land use, especially for sugar and glucose production, from the fossil energy consumption of about 15 MJ l −1 , and the related greenhouse gas (GHG) emissions of 0.91 kg CO 2 eq l −1 . Food waste leads to a loss of about 20 kcal l −1 . Bioenergy integration would allow a 13–15% damage reduction, mainly due to the substitution of indirect energy consumption. The effects on human health and ecosystem quality are limited. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the efficacy of short wave ultraviolet (UVC) irradiation for the inactivation of Aspergillus flavus or Aspergillus niger inoculated in peach nectar. A commercial UVC-disinfection unit with a total dose of 203kJ/m2 achieved 4 and 3 log reductions for A. flavus and A. niger, respectively. Variations observed in the characteristics of the nectar (acidity, color, pH, and soluble solids) before and after the treatment were minimal. The efficacy of combined treatments of UVC with commercially available food antimicrobial agents, potassium sorbate (KS, 250–2000ppm) and sodium benzoate (NB, 250–1000ppm) was tested. Inactivation effectiveness decreased with increasing KS concentration. The highest microbial inactivation (up to five logarithmic cycles) was achieved for A. flavus during the combined UVC–NB treatments, which also exhibited nectar microbial stability up to 15days at 25°C. Weibull model adequately described the UVC inactivation of A. flavus and A. niger, obtaining a shape parameter for both populations of n <1. Industrial relevance: Combined treatments of food antimicrobials and UVC irradiation can be utilized effectively for the reduction of microbial contamination of peach nectar. Potassium sorbate absorbs UVC-light therefore, in a combined treatment it can only be added after the UVC treatment; but sodium benzoate and UVC proved to be more successful at reducing microbial populations of A. flavus and A. niger than their individual treatments. [Copyright &y& Elsevier]

ABSTRACT Applicability of pulsed electric fields (PEFs) to process peach nectar as a function of electric field strength and treatment time with respect to microbial inactivation and measurement of physical and chemical properties of peach nectar was evaluated. No significant difference was detected in terms of pH, °Brix, titration acidity (TA), conductivity, color (L *, a * and b*), nonenzymatic browning index (NBI), metal ion concentration, ascorbic acid content and beta carotene concentration between control and PEF-treated peach nectar samples (P > 0.05). On the other hand, Escherichia coli O157:H7, Staphylococcus aureus, Listeria monocytogenes, Erwinia carotowora, Pseudomonas syringae, Botrytis cinerea and Penicillum expansum were significantly inactivated (P ≤ 0.05). PEF can successfully be applied to peach nectar with significant amount of microbial inactivation without a significant adverse effect on physical and chemical properties. PRACTICAL APPLICATIONS Pulsed electric field (PEF) processing, considered a novel technology, posses a significant potential to achieve nonthermal (cold) pasteurization and/or sterilization of liquid materials, especially fruit juices. This study was performed to determine potential use of PEF to process peach nectar based on the measurement of changes in physical and chemical properties as well as in microbial inactivation. PEF processing significantly inactivated inoculated microorganisms without adverse effects on both physical and chemical properties. Based on the results, it can be concluded that PEF technology can successfully be applied pasteurization of peach nectar. [ABSTRACT FROM AUTHOR]

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Consumers are looking even more for food with pleasant characteristics in terms of flavor, appearance, aroma and texture. Thanks to technological advances, it is possible to find low-calorie products with these characteristics, with competitive prices when compared with similar products containing sucrose. In this study, peach nectar samples containing sucrose and the sweeteners aspartame, cyclamate/saccharin 2:1 blend, stevia, sucralose and acesulfame-K, were evaluated by Descriptive Quantitative Analysis. This methodology is the most complete and sophisticated technique for the sensory characterization of a product, because it allows a complete description of all the attributes existent in such product. Eleven consumers were selected by their discriminative capacity, repeatability of judgment and agreement with the sensory team. Sucrose sample were at ideal sweetness and the sweeteners samples were at equi-sweet concentrations. The descriptive terms were yellow color (YCL), cloudy aspect (CLD), brightness (BRI), visual viscosity (VIS), peach aroma (PAR), sweet aroma (SAR), herb aroma (HAR), peach flavor (PFL), sweetness (SWE), bitterness (BIT), herb flavor (HFL), sourness (SOU), residual bitterness (RBT), residual sweetness (RSW), astringency (AST) and body (BOD). The results were evaluated by analysis of variance, Tukey's test and Principal Component Analysis. The results show that the samples did not have statistical difference (P ≤ 0.05) in the attributes YCL, CLD and BRI. The sample sweetened with sucrose presented higher grades in the attributes VIS, PAR, PFL, SWE and BOD, differing statistically (P ≤ 0.05) from the other samples. Samples containing Stevia received high grades in unpleasant attributes, such as HAR, HFL, BIT, RBT and RSW, which would certainly influence its acceptance in consumers' tests. Acesulfame-K also presented high grades in the attributes BIT and RBT. PRACTICAL APPLICATIONS Quantitative Descriptive Analysis is one of the most sophisticated methods to characterize sensory attributes of products, providing a complete description of important sensory properties. With this technique, it is possible to study qualitative and quantitative aspects of the products. This methodology is used when launching a new product; in quality control applications; to track sensory changes in a product over time; to correlate instrumental, chemical or physical with sensory measurements, among others. In this research, several lexicons were generated to describe the peach nectar sweetened with different sweeteners, highlighting some characteristics of sweeteners such as bitterness and residual tastes. It also presents a comparison among the nectar sweetened with sucrose and sweeteners and shows which sweetener has a descriptive profile more similar to sucrose. With this information, people suffering from diabetes or obesity, major problems in the whole world, could find a sugar substitute with similar properties of sucrose. [ABSTRACT FROM AUTHOR]

Abstract: Inhibitory effects of pulsed electric fields (PEF) on Penicillum expansum inoculated into sour cherry juice, apricot and peach nectars were determined based on germination tube elongation, spore germination rate, and light and scanning electron microscopy (SEM) observations in this study. After inoculation of juice/nectar samples with P. expansum spores at the level of 105–106 cfu/mL, the samples were processed by bench scale PEF pulse generator as a function of differing electric field strengths (0, 13, 17, 20, 23, 27, 30 and 34kV/cm) and processing times (0, 62, 94, 123, 163, 198 and 218μs). Results revealed that with an increase in electric field strength and processing time, germination tube elongation and spore germination rate were completely inhibited. Light and SEM observations revealed considerable morphological alterations in fungal conidia such as cytoplasmic coagulation, vacuolations, shrinkage and protoplast leakage. PEF processing of juice/nectars was demonstrated to be effective in inactivating P. expansum. To our knowledge, this is the first study confirming the inhibitory effects of PEF on germination tube elongation and spore germination rate of P. expansum in fruit juice/nectars. [Copyright &y& Elsevier]

Eight samples of peach nectars were profiled by a trained panel and assessed for overall liking by a consumer panel. Internal preference mapping was used to derive a multidimensional space of samples based only on acceptance data. The first three preference dimensions showed significant fit for 91.2% of the consumer population. According to the position of these consumers on the maps, four subgroups could be formed. The first dimension was mainly related to sweetness and off-flavour. The second dimension was related to acidity and texture attributes (body, viscosity, sliminess, mouth-coating) and the third dimension was defined by flavour intensity, peach flavour, and artificial and cooked flavours. Based on these results, the preference criteria of each consumer subgroups were established. [ABSTRACT FROM AUTHOR]

Presents a study that aims to optimize the acceptability of a low-calorie peach nectar formulation using different levels of guar gum and aspartame based on Response Surface Methodology (RSM). Comparison of the acceptability of the optimized product with commercial regular and low-calorie nectars; Preparation of 16 low-sugar peach nectar samples.

The effectiveness of pouches, including plastic and aluminum foil laminations, in preserving the physiochemical and sensory characteristics of peach nectar compared to the more traditional packages (can and glass jar) was determined. Three sucrose syrup to peach puree ratios (50:100, 60:100, 70:100) were tested and based on the results obtained from a sensory panel, the final study was performed using a ratio of 60:100. The sensory, color, viscosity, and chemical data showed that pouches made from aluminum foil laminations were as good in retaining the quality of the peach nectar as the jar and the can. Significant correlations were found between several instrumental and sensory parameters used in determining the quality of peach nectar. [ABSTRACT FROM AUTHOR]

Peach fruits (Prunus persica L.) contain a complex of nutritive and biologically active substances. The extraction of juice from peaches is relatively difficult due to the high content of fruit pulp so for the purposes of the juice industry, most peaches are processed in puree which is the basis for the production of peach juice products. Data on the nutrient content in peach juices-purees are few and require clarification and addition as applied to industrial products. The aim of the study was to investigate and update the composition of main nutrients of peach juice-puree. Material and methods . The nutrient composition of peach juice products of industrial production has been studied. Analysis of the results obtained in conjunction with the analysis of the data of reference books and scientific publications regarding peach fruits and juices-purees from them has been performed. Results and discussion . Nutrient profile of peach juice-puree has been established. The nutrient profile shows the content of more than 30 nutritive and biologically active substances. The prevailing saccharide in peach juice-puree is sucrose; glucose and fructose are present in lower concentrations. In addition to sugars, peach juice-puree contains sorbitol - about 0.4 g per 100 g. The total acidity of peach juice-puree is low, in 100 g there is an average of 0.5 g of organic acids, most of which are L-malic and citric acids. Regarding the polyphenols of peach juice-puree, the most significant are hydroxycinnamic acids, mostly chlorogenic, at the concentration of about 10 mg/100 g. The main type of peach juice products on the market are peach nectars containing 40-50% of juicepuree. Peach nectar is rich in vitamin E - more than 20% of the daily requirement per serving, dietary fiber (15% of the daily requirement for pectins and 5% of total dietary fibers), and the content of hydroxycinnamic acids in it fully satisfies or exceeds the adequate daily intake. A serving of peach nectar also contains on average 7% of daily requirement for β-carotene, 8% in copper, 6% in potassium. Conclusion . The most significant micronutrient and minor biologically active substances for peach juice products are dietary fibers, hydroxycinnamic (chlorogenic) acids, β-carotene, vitamin E, and potassium and copper., Competing Interests: The authors declare no overt and potential conflict of interest related to the publication of this article., (Copyright© GEOTAR-Media Publishing Group.)

Enterolobium cyclocarpum, (caro-caro), especie ampliamente diseminada en Venezuela, produce goma con alto rendimiento. Se estudió el comportamiento de este hidrocoloide como aditivo en la preparación de néctares de durazno. El ensayo consistió en seis tratamientos, utilizando diferentes concentraciones de la goma (0,20; 0,30; 0,50; 0,70; 1%), y un tratamiento control (sin goma). Las características físico-químicas (acidez, pH, sólidos solubles, viscosidad, estabilidad) y las propiedades sensoriales del producto elaborado se evaluaron. Se aplicó un diseño de bloques al azar con seis repeticiones. Los resultados mostraron que la viscosidad exhibida por los néctares elaborados a la mayor concentración (1%), se incrementó significativamente (P