Concentrated Apple Juice Research Articles

Concentration of natural aroma compounds from fruit juice hydrolates by pervaporation in laboratory and semi-technical scale. Part 2. Economic analysis

The second part of a two-article series presents an economic analysis of the production of concentrated apple juice hydrolates via pervaporation. The average permeability of the membrane and the results obtained for the semi-pilot scale studies presented in the first part of the paper allowed for the determination of the required membrane area for the separation of aroma compounds from apple hydrolate. The simulation was divided into the base case scenario and sensitivity analysis for both batch and continuous process configurations. The economic indicators made it possible to calculate the cost-effectiveness of the implementation of the proposed solution. Both the base case scenarios and their sensitivity analysis revealed that the continuous production generates significantly higher revenues over the batch case. The results of the economic analysis demonstrated that pervaporation is a profitable and feasible option for aroma recovery from fruit hydrolates.

Detection and quantification of Alicyclobacillus acidoterrestris by electrical impedance in apple juice

Alicyclobacillus acidoterrestris is a thermotolerant bacterium able to grow in fruit juices and drinks, as the spoilage by Alicyclobacillus in the final product does not product any gas, but leads to a “medicine flavor” due to the formation of guaicol. Also, its detection is a challenge for the quality control departments, because it takes several days to get the results of traditional microbiology methods. This study aimed at developing a more accurate electrical impedance technique for the detection of A. acidoterrestris in concentrated apple juice. Samples of apple juice were inoculated with A. acidoterrestris spores isolated from a peach and grape juice. For the spore germination, several heat-shock treatments were tested (80 °C/10 min, 70 °C/20 min and 60 °C/30 min). Direct and indirect electrical impedance was applied to detect and quantify the microorganism in the inoculated apple juice, using BAT broth and Bimedia 002A (pH 4). The 80 °C/10 min treatment was selected for spore activation. The valid electrical impedance technique was the indirect method in BAT broth, which measured the changes in the impedance through the formation of CO2. In addition, a positive correlation (r = 0.98, R2 = 0.97) was observed between the classical microbiology (BAM agar) and the indirect impedance method.

Optimum design of a multi-stage reverse osmosis process for the production of highly concentrated apple juice

Reverse Osmosis (RO) membrane process has been commonly used for clarification and concentration of apple juice processes, due to significant advance in membrane technology, requirements for low energy and cost, and effective retention of aroma components. In this paper, a multi-stage RO industrial full-scale plant based on the MSCB 2521 RE99 spiral-wound membrane module has been used to simulate the process of concentrating apple juice and to identify an optimal multi-stage RO process for a specified apple juice product of high concentration measured in Brix. The optimisation problem is formulated as a Nonlinear Programming (NLP) problem with five different RO superstructures to maximise the apple juice concentration as well as the operating parameters such as feed pressure, flow rate and temperature are optimised. A simple lumped parameter model based on the solution-diffusion model and the contribution of all sugar species (sucrose, glucose, malic acid, fructose and sorbitol) to the osmotic pressure is assumed to represent the process. The study revealed that the multi-stage series RO process can optimise the product concentration of apple juice better than other configurations. It has been concluded that the series configuration of twelve elements of 1.03 m2 area improves the product apple juice concentration by about 142% compared to one element. Furthermore, the feed pressure and flow rate were found to have a significant impact on the concentration of the apple juice.

A new method developed to characterize the 3D microstructure of frozen apple using X-ray micro-CT

Non-destructive imaging techniques have become indispensable to improve insights into the microstructural changes occurring in fruit tissue during freezing. Here, apple cortex tissue samples were frozen using different freezing rates: (i) slow freezing (2.0 °C per min.), (ii) intermediate freezing (12.6 °C per min.) and fast freezing (18.5 °C per min.). Temperature-controlled X-ray micro-CT was optimized and then applied to visualize and quantify the 3D microstructure and ice crystal distribution at a pixel resolution of 3.8 μm. Ice crystal size distributions with mean equivalent diameters of about 41 ± 3.5 μm, 55 ± 7.4 μm and 71 ± 9.6 μm were obtained for the fast, intermediate and slow freezing rates, respectively. A new imaging methodology was developed and validated to allow segmentation of the ice crystals in frozen apple tissue using the X-ray attenuation coefficients of the reference model samples, i.e. frozen pure water and concentrated apple juice.

Investigation of optimum ohmic heating conditions for inactivation of Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in apple juice

BackgroundControl of foodborne pathogens is an important issue for the fruit juice industry and ohmic heating treatment has been considered as one of the promising antimicrobial interventions. However, to date, evaluation of the relationship between inactivation of foodborne pathogens and system performance efficiency based on differing soluble solids content of apple juice during ohmic heating treatment has not been well studied. This study aims to investigate effective voltage gradients of an ohmic heating system and corresponding sugar concentrations (°Brix) of apple juice for inactivating major foodborne pathogens (E. coli O157:H7, S. Typhimurium, and L. monocytogenes) while maintaining higher system performance efficiency.ResultsVoltage gradients of 30, 40, 50, and 60 V/cm were applied to 72, 48, 36, 24, and 18 °Brix apple juices. At all voltage levels, the lowest heating rate was observed in 72 °Brix apple juice and a similar pattern of temperature increase was shown in18–48 °Brix juice samples. System performance coefficients (SPC) under two treatment conditions (30 V/cm in 36 °Brix or 60 V/cm in 48 °Brix juice) were relatively greater than for other combinations. Meanwhile, 5-log reductions of the three foodborne pathogens were achieved after treatment for 60 s in 36 °Brix at 30 V/cm, but this same reduction was observed in 48 °Brix juice at 60 V/cm within 20 s without affecting product quality.ConclusionsWith respect to both bactericidal efficiency and SPC values, 60 V/cm in 48 °Brix was the most effective ohmic heating treatment combination for decontaminating apple juice concentrates.

Concentration of apple juice using a vacuum microwave evaporator as a novel technique: Determination of quality characteristics

AbstractThis study was evaluated the use of a novel concentration technique, a vacuum microwave evaporator (VME) in the production of clear apple juice concentrate and the investigation of its effects on the quality characteristics of the juice. The optimum processing conditions of the VME for apple juice concentrate were determined using response surface methodology. The apple juice concentrate was produced by VME, a rising film evaporator (RFE), and a rotary evaporator (RE) at the optimum process conditions. The results show that the evaporation rate of VME was three times higher than that of RE and was two times higher than that of RFE. VME produced minimum changes in the color of the apple juices (L*, a*, b*, ΔE, Hue°, and ΔC) compared to RE and RFE. VME was also found the best group that preserved the quality characteristics of apple juices (TTA, NEBI, and TPC) compared with conventional evaporation methods.Practical applicationsMicrowave heating provides volumetric heating of food. The concentration carried out quickly with the combined system, microwave and vacuum, which allows mass and energy transfer quickly at a short time. The physicochemical, and biochemical properties of the concentrated apple juices processed using VME were found to be better than those of the juices produced using the other conventional methods. The obtained data can be useful for optimization of fruit juice concentrate production in industrial concentration processes.

Development of a mathematical model for apple juice compounds rejection in a spiral-wound reverse osmosis process

The use of Reverse Osmosis (RO) membrane processes for the clarification and the concentration of apple juice is proposed as an alternative to the conventional concentration technique, which is based on evaporation and freezing. Several models have been published on RO process models relying on different assumptions that predict the permeate flux and aroma compounds rejections for aqueous solutions apple juice. The solution-diffusion model (Lumped model) has been applied for the previous models. The main instrument of this study is the use of the gPROMS software to develop a new distributed steady state model that will relax a number of earlier assumptions.The model has been validated with an observational data of apple juice filtration derived from the literature by analysing the permeate flux and the performance of membrane rejection at different concentrations, temperatures and pressures for a laboratory scale of spiral-wound RO module. Simulated results corroborate with experimental and model predictions.

Market competition and concentration in the world market of concentrated apple juice

In the study, I examined the market competition and concentration in the word market of concentrated apple juice. I used RCA index to determine comparative advantages In the world China possesses the strongest comparative advantages. Besides China, Poland, Hungary, Chile, Ukraine, Turkey and Moldova possess strong comparative advantages too. I used Herfindahl-Hirschman-index to determine the market concentration. Based on it – excluding the high Chinese market share between 2006 and 2010 – the world market of concentrated apple juice can be considered as a market with a moderate concentration. Based on the secondary research the study has a detailed examination of cause and effect relationships behind the RCA and HHI index results

Effect of temperature and nutrient concentration on the growth of six species of sooty blotch and flyspeck fungi

Summary. We assessed the effects of temperature and nutrient concentration on the growth of commonly occurring members of the sooty blotch and flyspeck (SBFS) complex in the Midwest United States. Radial growth in vitro of two isolates of each of six SBFS species (Dissoconium aciculare, Colletogloeum sp. FG2, Peltaster sp. P2, Sybren sp. CS1, Pseudocercosporella sp. RH1, and Peltaster fructicola) was measured at 10, 15, 20, 25, 30 and 35°C for 7 weeks. Optimal growth for all six species occurred at 20 to 25°C, with slower growth at 10 and 15°C and little to no growth at �0 or �5°C. Differences in growth rate among species were evident at 10, 15, and 35°C. In a separate trial, the same isolates were incubated at 25°C in darkness on cellulose membrane (12-14 kDa) placed on Noble agar that had been amended to obtain concentrations of 0, 0.01, 0.05 or 0.5% apple juice. After 3 weeks, colonies were digitally photographed and colony opacity was assessed. The presence and concentration of apple juice strongly impacted colony morphology as evidenced by changes in colony tone, and some species were more sensitive to changes in apple juice concentration than others. These findings are the first published evidence of differences among newly described SBFS species in response to temperature and nutrient concentration.

Innovation and Practice of Separation Pre-Pressing Technology and Whole Apple Utilization

Apple and apple products are one kind of popular fruit and fruit products among the world. The planting acreage, output and trade quantity of the apples in the world are keeping increasing. At present, China has become the biggest apple producing and trading country. However, Chinese companies of concentrated apple juice suffer a serious deficit since the global financial crisis. The most important reasons are the rising cost of raw materials, less utilization and the single products. In order to solve these problems, pressing pre-peeled apple and the whole apple utilization were proposed, which not only solved the less processing quality, discoloration, pesticide residues and other issues, but also processed apples based on the nutrients of different parts (juice, flesh, peel and seeds). It may extend juice processing chain and achieve zero waste of processing apples which will be the future direction of the juice industry.

Mixing Process of Apple Juice Concentrate

The rheological properties of apple concentrate were studied over the range 4-70°C, solid concentration 71 wt% of apple concentrate, and shear rate 9.3-74.4 s-1. Shear rate - shear stress data indicate that apple juice concentrate (71%) behaves as pseudoplastic fluid at (4, 10°C) while the concentrate exhibited Newtonian fluid at temperatures studied (30-70°C). The effect of rheological properties of apple juice concentrate on mixing parameters was investigated. An impeller mixer was connected with ammeter in order to predict the power of the mixer at different impeller to column diameter (D/T). The relation between power number, blend number, pumping number and Reynolds number were calculated at different D/T ratio.

Progressive freeze-concentration of apple juice and its application to produce a new type apple wine

Progressive freeze-concentration (PFC) by a tubular ice system was successfully applied to concentrate apple juice from 13.7 to 25.5 oBrix under a program controlled operation for the coolant temperature and the circulation pumping speed. The organic acid distribution and the flavor profile analysis revealed that no substantial differences were observed for the juice before and after concentration both in organic acids and flavor components showing the high quality concentration by PFC. This was also confirmed by electronic taste and flavor analyzers. The PFC-concentrated apple juice was fermented to obtain a new type apple wine with alcohol content as high as 13.7 vol-% without chaptalization. The organic acid distribution was slightly changed before and after fermentation while the flavor profile changed drastically. The present technique will be applicable to produce new type of wine from many other fruits.

Combined effect of sugar content and pH on the growth of a wild strain of Zygosaccharomyces rouxii and time for spoilage in concentrated apple juice

The objective of this study was to evaluate the combined effect of sugar content (66–70 °Brix) and pH (2.0–3.5) on the growth of a wild strain of Zygosaccharomyces rouxii B-WHX-12-54 by response surface (RS) methodology. Experiments were performed in concentrated apple juice inoculated with this strain at standard storage condition (isothermal, 25 °C) for 60 days. Results show that pH was the most significant limiting factor that affects the growth parameters (potential maximum growth rate and lag phase duration), although the effect of sugar content was also significant. In a second experiment, the time for spoilage (TFS) by this strain in concentrated apple juice was assessed under isothermal (25 °C) and non-isothermal conditions, in an attempt to simulate standard storage and overseas shipping temperature conditions, respectively. Results show that pH was again the environmental factor with the highest effect on delaying the spoilage of the product caused by this strain. Although concentrated apple juice stored under non-isothermal condition showed lower microbial stability (evidenced in lower TFS values) than that stored under standard isothermal condition, a pH value below 2.3 was sufficient to extend the shelf life of the product to more than 60 days under both temperature conditions. The results obtained in this study could be used by producers and buyers to predict and control the growth and TFS of Z. rouxii strain B-WHX-12-54 in concentrated apple juice.

Comparison of Artificial Neural Network and Response Surface Methodology Performance on Fermentation Parameters Optimization of Bioconversion of Cashew Apple Juice to Gluconic Acid

Abstract The study examined the impact and interactions of cashew apple juice (CAJ) concentration, pH, NaNO3 concentration, inoculum size and time on gluconic acid (GA) production in a central composite design (CCD). The fermentation process and parameters involved were modeled and optimized using artificial neural network (ANN) and response surface methodology (RSM). The ANN model established the optimum levels as CAJ of 250 g/l, pH of 4.21, NaNO3 of 1.51 g/l, inoculum size of 2.87% volume and time of 24.41 h with an actual GA of 249.99 g/l. The optimum levels predicted by RSM model for the five independent variables were CAJ of 249 g/l, pH of 4.6, NaNO3 of 2.29 g/l, inoculum size of 3.95% volume, and time of 38.9 h with an actual GA of 246.34 g/l. The ANN model was superior to the RSM model in predicting GA production. The study demonstrated that CAJ could serve as the sole carbon source for GA production.

Simple linear correlation between concentration and electrical properties of apple juice

The results of studies undertaken with the aim of determining the effect of Total Soluble Solids (TSS) on the electrical conductivity of reconstituted apple juice and the evaluation of mathematical relationships between TSS and electrical properties of the juice are presented in the paper.The experimental material was the apple juice (8–12 °Brix) prepared from a concentrate (66.3 °Brix), n=21. The TSS content was determined by the refractometric method. Measurements of the impedance (Z), resistance (R) admittance (Y) and conductance (G) were performed by means of the HP 4263B meter at a constant voltage of 200mV, frequencies ranged from 100Hz to 100kHz and a temperature of approx. 20°C. Linear correlations were derived using regression analysis to predict TSS as a function of electrical parameters (Y, G, Z and R). The relations observed were described with the regression equations in a standard form of: y=a±bx. These equations are suitable for further studies to develop methods for rapid determination of the TSS content in different fruit juices as well as for the detection of their adulteration. For this purpose, the measurements of admittance or conductance over the range of 1–100kHz may be applied.

Appraisal of Artificial Neural Network and Response Surface Methodology in Modeling and Process Variable Optimization of Oxalic Acid Production from Cashew Apple Juice: A Case of Surface Fermentation

This study assessed the effects and interactions of cashew apple juice (CAJ) concentration, pH, time, methanol concentration, and NaNO3 concentration on oxalic acid fermentation in a central composite design. The efficacies of artificial neural network (ANN) and response surface methodology (RSM) in modeling and optimizing the process were evaluated using correlation coefficient (R), coefficient of determination (R2), and absolute average deviation (AAD). The highest oxalic acid production observed was 120.66 g/L under optimum values of a CAJ concentration of 291 g/L, pH of 6.9, time of 10.82 days, methanol concentration of 2.91% (v/v), and NaNO3 concentration of 1.05 g/L that were numerically predicted by the developed RSM quadratic model. Using the developed ANN model coupled with rotation inherit optimization, the highest oxalic acid production observed was 286.75 g/L under the following optimum values: CAJ of 291 g/L, pH of 6.5, time of 12.64 days, methanol concentration of 3.82% (v/v), and NaNO3 concentration of 2.41 g/L. The results showed that the ANN model (R = 0.9996, R2 = 0.9999, AAD = 0.21%) was better than the RSM model (R = 0.9986, R2 = 0.9973, AAD = 1.00%) for optimizing oxalic acid fermentation. The use of the ANN model led to a 2.4-fold increase in oxalic acid yield over the RSM model.

Dynamics of the loss and emergence of volatile compounds during the concentration of cashew apple juice (Anacardium occidentale L.) and the impact on juice sensory quality

Concentrating cashew apple juice alters the beverage aroma and flavor, compromising consumer acceptability of the concentrated beverage. To understand the mechanisms involved in these changes, this research characterized the dynamics of the loss and emergence of volatile compounds during cashew apple juice concentration, reporting their impact on beverage sensory quality. Fresh cashew apple juice (10.3°Brix) was concentrated in a thermal-siphon type evaporator operating in a closed system. Five samples were taken throughout the concentration process with the following soluble solids contents: 11.8°Brix, 14.9°Brix, 20.2°Brix, 29.6°Brix and 42.1°Brix. Trained judges rated the aroma note intensities, described as “fresh cashew apple” and “cooked” as perceived in the fresh and concentrated beverages. The headspace volatiles of the six samples were identified and quantified by GC–MS. The results indicated the esters as the major component in the fresh juice (226.46μgkg−1) representing 45.0% of the total mass of volatiles, followed by the terpenes (118.98μgkg−1), acids (45.23μgkg−1), aldehydes (39.10μgkg−1), alcohols (18.91μgkg−1), lactones (19.15μgkg−1), hydrocarbons (18.02μgkg−1) and ketones (11.05μgkg−1). Predictive statistical models (R2>0.956, p≤0.002) revealed that on reaching 14.9°Brix, the ester concentration declined more than 90%, the terpene content almost 100%, alcohols 85%, aldehydes 80% and hydrocarbons 90%. At 14.9°Brix, the intensity of “fresh cashew apple” aroma still predominated in the juice, but the panelists detected the presence of a weak “cooked” aroma. Concentration of the beverage to 20.2°Brix or above expressively increased the cooked aroma intensity and the concentration of hydrocarbons, alcohols and some aldehydes usually associated with off-flavors such as pentanal and decanal. This raises the possibility that some of these compounds might have been formed during juice processing. Juice with better sensory quality could possibly be obtained by concentrating the beverage to levels below 20.2°Brix, recovering the esters that evaporated off the juice until ~15°Brix is reached, and re-adding them to the juice concentrated.

Optimization of low alcoholic bitter gourd apple beverage by applying Response surface methodology (RSM)

Bitter gourd (Momordica charantia) - a member of the cucurbitaceae family, and a popular vegetable among gourds is known as bitter melon, bitter gourd, balsam pear and karela. It has bitter taste and is known to possess many medicinal properties including those for the cure of diabetes caused by insulin deficiency or resistance. Attempts were made to prepare a low alcoholic beverage from bitter gourd and apple by standardizing the concentration of apple juice, DAHP and inoculum size by applying central composite design (CCD) of RSM. On the basis of physico-chemical and sensory characteristics, a run having 40% apple juice, 0.15 % DAHP and 2.5% inoculum level were rated as the best. It has the highest TSS, rate of fermentation, ethanol, reducing and, total sugars and total phenols. With the addition of 0.15% DAHP as a nitrogen sources, bitter gourd based wine had the highest total soluble solid (TSS), titratable acidity, ethanol, total and reducing sugar content and lowest volatile acidity and higher alcohols. Different concentrations of yest innoculum used did not significantly influenced most of the physic-chemical characteristics. Must inoculated with 2.5% Saccharomyces cerevisiae var ellipsoideus used for the preparation of bitter gourd based wine had the highest fermentability and ethanol content. However, the product being low alcoholic, need pasteurization at 62 degreesC for 20 min. keeping a head-space of 2.5 cm in a glass bottle. Bitter gourd beverage so prepared holds promise as a medicinal drink as bitter gourd is known to be antidiabetic.

Effects of magnesium ions on both VHG batch and continuous fruit wine fermentations

In Poland, fruit wines or aromatized fruit wines are semi-sweet or sweet and contain approximately 15–16% (v/v) ethanol. Their production can be classified as a very high-gravity (VHG) fermentation. Magnesium has a beneficial effect on VHG fermentations as it protects the yeast cells against ethanol, osmotic and temperature stress. The effect of the magnesium concentration in an apple must, containing 32% sugars, on the fermentative parameters of batch and continuous fermentations was assessed. In the batch process, a magnesium concentration of ~8.5 mg/L resulted in decreased the ethanol production in comparison to a magnesium concentration of ~250, 490 and 970 mg Mg2+/L. The highest amount of Mg also caused a metallic taste. A continuous fermentation was carried out for 2.5 months in a four-column packed-bed fermentor. The medium contained ~50, 250 and 490 mg Mg2+/L and the yeast was immobilized on foam glass. During the continuous fermentation, no differences at p ≤ 0.05 in terms of fermentative parameters were seen with magnesium additions. The same beginning amount of magnesium ions in the medium led to a similar use of this element, both in batch and in continuous fermentation. The more Mg2+ that was present in the medium, the more Mg2+ was used by the yeast. The results suggest that the minimal dose of magnesium, under the described conditions, is 50 mg/L, corresponding to the amount of Mg in the medium prepared using concentrated apple juice and tap water. This finding has industrial significance, as Polish wine companies prepare their fruit musts using tap water. Copyright © 2014 The Institute of Brewing & Distilling

Inactivation of Alicyclobacillus acidoterrestris Spores in Apple and Orange Juice Concentrates by Gamma Irradiation

The objective of this study was to evaluate the effect of different concentrations of reconstituted apple and orange juice on reduction of Alicyclobacillus acidoterrestris spores by gamma irradiation. Spores of A. acidoterrestris were inoculated into three concentrations of apple (18, 36, and 72 °Brix) and orange (11, 33, and 66 °Brix) juice and subjected to five radiation doses (1, 3, 5, 7, and 10 kGy). No significant reductions (P > 0.05) in spores were observed after the 1-kGy treatment for all apple and orange concentrations. Spores in 18, 36, and 72 °Brix apple juice concentrates subjected to 10 kGy were reduced to 4.34, 3.9, and 3.84 log CFU/ml, respectively. Similar results were observed for orange juice. When 10 kGy was applied to 11 °Brix orange juice, populations of spores were reduced by 5 log CFU/ml. The reduction of spores in 33 and 66 °Brix orange juice concentrates exposed to 10-kGy gamma irradiation was 4.54 and 3.85 log CFU/ml, respectively. Juice concentration did not affect (P > 0.05) the number of surviving A. acidoterrestris spores from the same kGy treatment. Gamma irradiation treatment did not change the pH or water activity of the juice (P > 0.05).