Impact of enzyme on quality of blackcurrant and plum juices

The aim of work was optimization of technology of cloudy blackcurrant and plum juices production. The major concern was the increase of product cloudiness and its stability. Red fruit were processed with commercial pectinolytic preparations (Pectinex BE Colour, Pectinex BE XXL, and mixture of Rohapect PTE with Rohament PL). The effect of enzyme dose, maceration time and addition of ascorbic acid (in case of plum) on juices quality was investigated. Using single enzyme, either polygalacturonase or pectin lyase did not allow obtaining juices with high enough turbidity, however appropriate enzyme mixture allowed to obtain cloudy juice with the turbidity of at least 230 NTU for blackcurrant and above 500 NTU for plum juice. The best pressing-yield for blackcurrant was achieved with polygalacturonase and pectin lyase, 65 g/100 g after 1 h and 74 g/100 g after 4 h of pectinolysis. The macerating mixture gave about 58÷59 g/100 g yield, irrespectively of enzymation time. Pressing-yield of plum juices was in the range of 94÷97 g/100 g due to the fact that practically only skins were retained on pressing cloth. Addition of ascorbic acid (AA) during plum juice processing in quantity of 500 mg/kg had protective effect on anthocyanins. In control plum juices range of anthocyanins contents were 12.1÷16.5 mg/100 ml while in juice with AA addition even 21.4÷24.5 mg/100 ml.     

THE EFFECT OF ENZYMATIC MASH TREATMENT, PRESSING, CENTRIFUGATION, HOMOGENIZATION, DEAERATION, STERILIZATION AND STORAGE ON CARROT JUICE

The enzyme preparation Pectinex Smash XXL was employed to macerate the carrot pulp, the effect of enzymatic mash treatment (EMT), pressing, centrifugation, homogenization, deaeration, sterilization and storage on carrot juice was investigated. As compared with the control sample, an increase of juice yield, total soluble solid (TSS) and carotenoids in carrot juice was close to 20%, 1% and 26 mg/kg, respectively, after EMT. The EMT also increased the color parameters CIEL*, a*and C*values in carrot juice. However, it significantly decreased the viscosity from 2.54 to 2.09 mPa·s. The centrifugation resulted in a significant decline in turbidity from 240.33 to 187.33 NTU and a significant increase in the color parameters in carrot juice. After homogenization, the turbidity and the carotenoids in carrot juice were significantly reduced from 187.33 to 161.67 NTU and from 61.87 to 58.76 mg/kg, respectively. The turbidity and carotenoids in carrot juice decreased during storage, and all the color parameters had a closer relationship with storage temperature and time; higher storage temperature and longer storage time caused greater loss of color.     

Purification of polygalacturonase from Aspergillus awamori Nakazawa MTCC 6652 and its application in apple juice clarification

Polygalacturonase (PG) is necessary during fruit juice clarification process for the degradation of insoluble viscous pectinacious compounds. In the present study, PG from Aspergillus awamori Nakazawa MTCC 6652 produced by solid-state fermentation of mosambi (Citrus sinensis var mosambi) peel was decolorized and purified 34.8 fold with 69.8% recovery exploiting activated charcoal. The SDS-PAGE profiling revealed molecular weight of the purified PG as 30 kDa. The optimum pH and temperature of the purified enzyme were 4.5 and 50 °C, respectively. After decolorization and purification it was applied in the apple juice clarification process. The clarified juice exhibited 38% viscosity reduction with % T₆₆₀ of 93%, A₄₂₀ of 0.3 and pH 3.     

Effect of pectinase treatment on extraction of antioxidant phenols from pomace,for the production of puree-enriched cloudy apple juices

Effects of pomace maceration on yield, turbidity, cloud stability, composition of phenolics, antioxidant activity and colour properties were studied, to evaluate the potential applicability of enzyme preparations in puree-enriched cloudy apple juice production. The yield of mixed juice and puree from pomace obtained in the enzymatic processing of apple ranged from 92.3% to 95.3%, significantly higher than the yield from the control without enzymatic pomace treatment (81.8%). Higher turbidity was obtained upon pomace treatment with Pectinex XXL and Pectinex Ultra SPL enzymes. The total content of phenolic compounds in apple pomace was higher than in raw juices (1520 mg/kg and 441 mg/L, respectively). The total polyphenol yields were higher in juices treated with Pectinex AFP L-4, Pectinex Yield Mash and Pectinex XXL, as compared to the control treatment. During 6 months of storage, a significant change was observed in the content of polyphenols, especially in procyanidin fractions.     

Effect of UV-LED irradiation processing on pectolytic activity and quality in tomato (Solanum lycopersicum) juice

The aim of this research was to analyze pectolytic activities (pectinmethylesterase “PME” and polygalacturonase “PG”) and physical qualities in tomato juice treated by UV-LED, Hot Break (HB), and Cold Break (CB) processing. Tomato juice treated by UV-LED (117 mJ/cm²) obtained a residual PME activity similar to that of CB, and tomato juice treated by UV-LED (351 mJ / cm²) had a residual PME activity 28.3% lower than HB (p < 0.05). The effect of UV-LED on PG activity was similar to HB and 49% lower than CB (p < 0.05). Furthermore, UV-LED processing caused a decrease in pH and total acidity and a significant increase in total lycopene content. Antioxidant activity and viscosity for UV-LED processing were similar to CB, total polyphenol content and °Brix were similar to HB (p > 0.05). Therefore, this study provides a promising application of UV-LED technology for controlling enzymatic activity in tomato juice, and an alternative to heat treatment.Industrial relevanceNowadays, the tomato industry uses heat treatments to inactivate pectolytic enzymes. UV-LED technology could have an industrial appreciation, as it was efficient in decrease the activity of these enzymes, in addition, preserved and increased some bioactive compounds. Therfore, it is proposed as an efficient method for processing fruit and vegetable juices. Nevertheless, further studies are needed to clarify the effect of this technology on pectolytic enzymes and quality parameters in liquid fruit and vegetable foods.     

Effect of enzyme‐aided pressing on anthocyanin yield and profiles in bilberry and blackcurrant juices

Bilberries (Vaccinium myrtillus) and blackcurrants (Ribes nigrum) were treated with extensive dosages of commercial cell wall degrading enzyme preparations, i.e. Econase CE, Pectinex Ultra SP‐L, Pectinex Smash, Pectinex BE 3‐L and Biopectinase CCM. The enzymes were dosed based on the polygalacturonase activity. The juice yield was improved in both berries as a result of the enzymatic treatment. The improvement was more pronounced with blackcurrants owing to their thicker cell walls. The impact of the enzymatic treatment on anthocyanins present in the juices was investigated using HPLC‐DAD. The enzyme preparations affected the contents and composition of anthocyanins in the juices. Pectinex Ultra SP‐L, Pectinex Smash, Pectinex BE 3‐L and Biopectinase CCM increased the total content of anthocyanins by 13–41% in the bilberry juices and by 18–29% in the blackcurrant juices. Econase CE, however, produced a dramatic decrease in the total anthocyanin content in the bilberry juice due to its enzyme profile, whereas no such effect was observed with the blackcurrant juice. All the enzyme mixtures tested produced a total or extensive loss of anthocyanidin galactosides in bilberry juice. Commercial enzyme preparations used in the production of berry juices can improve extraction of anthocyanins into the juice. However, they may effectively hydrolyse certain glycosides and thus affect the profile of extracted anthocyanins. Copyright © 2005 Society of Chemical Industry     

Changes in quality attributes of pulsed light and thermally treated mixed fruit beverages during refrigerated storage (4 °C) condition

The effect of batch pulsed light (PL) irradiation (3000 J cm⁻²) on the shelf-life of the beverage blend comprising apple ber (Indian jujube), carambola (star fruit), and black table grapes was investigated. The equivalent thermally treated beverage (90 °C|5 min) exhibited greater stability from microbial and enzymatic spoilage but retained 27% less antioxidants and 14% less vitamin C than PL-treated juice. Thermally and PL-treated blends possessed sensory scores of 5.8 and 7.2, respectively. The beverage's microbial shelf-life (population ≤ 6-log₁₀ cfu/mL) was extended to 45 days at 4 °C after the PL treatment. The PL exposure did not alter the pH and soluble solids during storage. The PL-treated juice, after 45 days, was placed on par with the freshly prepared juice by the sensory panel. The PL-treated juice preserved 61% more antioxidants, 38.8% more phenolics, and 68.2% more vitamin C than the thermally pasteurized beverage after 45 days of refrigerated storage.Industrial relevanceWhile the fruit processing industry demands microbial safety and enzymatic stability, today's consumer demands juices of high nutritional quality. This study utilizes under-explored fruits like apple ber (Indian jujube) and carambola (star fruit) to make a shelf-stable mixed fruit beverage. This study will help the industry understand the potential of PL treatment in accomplishing microbial safety, enzymatic stability, and nutritional quality, along with the utilization of under-explored fruits.     

Rapid Extraction of Pawpaw Juice with the Application of Locally Produced Pectic Enzymes from Saccharomyces Cerevisiae ATCC 51712

Pawpaw (Carica papaya) fruit is highly perishable; hence, conversion into a value-added product such as juice concentrate will be useful. Pawpaw fruit is, however, high in pectin; therefore, its juice extraction is difficult without an extraction aid such as the addition of pectic enzymes. Our laboratory has developed a simple enzymatic method that enables the extraction of pawpaw juice with considerable ease. Pectic enzymes were obtained from Saccharomyces cerevisiae (ATCC 52712) cultured in pawpaw juice for 6 days at room temperature (25–28°C) and centrifuged to obtain the enzyme in the supernatant. Addition of this enzyme (32 mg total protein) to 200 g pawpaw mash and incubation for 30 min resulted in significant (P < 0.05) reduction in the viscosity of the mash with corresponding increases in the flow rate of free-run juice (85%). Simultaneously, large increases in the volume of free-run juice (180%) over the controls were obtained. Since the overall increase in total juice volume was only 35% as compared with 180% for volume of free–run juice and 80% increase in flow rate for free–run juice, it was concluded that the major effect of the enzyme treatment on pawpaw juice extraction is on the decrease in processing time as a result of the degradation of the pectin in the fruit flesh.     

Enzymatic added extraction and clarification of fruit juices–A review

Enzymatic treatment for juice extraction is most commonly used now a days. The enzymatic process is claimed to offer a number of advantages over mechanical-thermal comminution of several fruit pulps. Enzymes are an integral component of modern fruit juice manufacturing and are highly suitable for optimizing processes. Their main purposes are: increase extraction of juice from raw material, increase processing efficiency (pressing, solid settling or removal), and generate a final product that is clear and visually attractive. Juice extraction can be done by using various mechanical processes, which may be achieved through diffusion extraction, decanter centrifuge, screw type juice extractor, fruit pulper and by different types of presses. Enzymatic treatment prior to mechanical extraction significantly improves juice recovery compared to any other extraction process. Enzymatic hydrolysis of the cell walls increases the extraction yield, reducing sugars, soluble dry matter content and galacturonic acid content and titrable acidity of the products. Enzymatic degradation of the biomaterial depends upon the type of enzyme, incubation time, incubation temperature, enzyme concentration, agitation, pH and use of different enzyme combinations. We can conclude from the technical literature that use of the enzymes i.e. cellulases, pectinases, amylases and combination of these enzymes can give better juice yield with superior quality of the fruit juice. Pectinase enzyme can give maximum juice yield i.e. 92.4% at 360 minutes incubation time, 37°C incubation temperature and 5 mg/100 g of enzyme concentration. Whereas the combination of two enzymes i.e. pectin methyl esterase (PME) and polygalacturonase (PG) at 120 minutes of incubation time, 50°C of incubation temperature and 0.05 mg/100 gm of enzymatic concentration can give the maximum yield of 96.8% for plum fruits. This paper discusses the use of enzymes in fruit juice production focusing on the juice recovery, clarity and effect of the particular enzyme on the biochemical properties of the fruit juices.     

Optimising enzymatic maceration in pretreatment of carrot juice concentrate by response surface methodology

In this paper, enzyme preparation for carrot pulp maceration was screened out and enzymatic maceration processing condition of the carrot pulp was optimised by response surface methodology for carrot juice concentrate. Pectinex Smash XXL was the best commercial enzyme preparation than Pectinex Ultra SP‐L, Pectinase FNP‐1 and cellulose FNC‐1 employed in the carrot juice processing in the study. The effect of enzyme concentration and incubation time and their complex interaction on juice β‐carotene content, juice yield and viscosity in the maceration process was studied by using experiments of central composite rotatable design. The results indicated that under the optimal conditions that the enzyme concentration was 100 mL t^?1 and incubation time was 80 min, the juice β‐carotene content was ≥54.2 mg kg^?1, the juice yield ≥63.5% and the juice viscosity ≤2.1 mPa S.     

Effect of mash maceration and ripening stage of apples on phenolic compounds and antioxidant power of cloudy juices: A study using chemometrics

The effects of different enzymatic preparations on total phenolic content, phenolic profile (HPLC), and ferric reducing antioxidant power (FRAP) of cloudy juices from Lis Gala and Fuji Suprema apples varieties, at three ripening stages (unripe, ripe and senescent) were investigated using Principal Component Analysis and Hierarchical Cluster Analysis. The commercial preparations enzymatic (Ultrazym^® AFPL; Pectinex^® Ultra Clear; Pectinex^® SMASH XXL; Panzym^® YieldMASH) increased the total phenolic compounds and ferric reducing capacity of the cloudy juice from unripe and ripe Lis Gala (respectively by 67 and 49% for unripe apples, and 28 and 33% for ripe apples) and unripe Fuji Suprema apples (23 and 55%), while for the ripe Fuji Suprema apples only Pectinex^® Ultra Clear and Panzym^® YieldMASH had this effect. No significant (p > 0.05) was observed on senescent stage, whatever the enzymatic preparation. Enzymatic preparations could increase phenolic compounds concentration and antioxidant capacity of cloudy apple juice, but this effect depended on the maturity of the apples.     

Enzymatic Clarification of Fruit Juices by Fungal Pectin Lyase

The activity of pectic enzymes was measured in culture filtrates of four selected fungal strains. Pectin lyase (PL) activity was produced by all fungi, but pectinesterase activity was not detected in culture filtrates of the strain Penicillium expansum F16. The use of crude enzymes resulted in good clarification of apple juice as evaluated by an increase in transmittance at 660 nm. PL activities were partially purified by dye-affinity chromatography on Blue Sepharose. The enzyme was bound to the column and eluted in a single peak, free of PE activity, and not coinciding with the major amount of protein. Apple, grape, and passion fruit juices were effectively clarified by these partially purified enzymes. Methanol content was determined by gas-liquid chromatography, being undetectable in the clarified juices. These pectic enzymes demonstrate potential for use in fruit juice processing.     

Bioethanol production from sugar beet molasses and thick juice by free and immobilised Saccharomyces cerevisiae

The aim of this study was the investigation and comparison of the potential of sugar beet molasses and thick juice as raw materials for bioethanol production, as renewable and sustainable energy sources. Ethanol fermentation of a wide range of initial sugar concentrations (100–300 g/L) was performed using either free or immobilised Saccharomyces cerevisiae in calcium alginate beads in the absence of any added nutrients. In general, immobilised cells showed better fermentative performance, enhanced ethanol productivity, stability and cell viability compared with free cells, under the same fermentation conditions. The high concentration of non‐sugar components contained in molasses affected yeast fermentation performance and viability. Maximum ethanol concentration in fermented media of 84.6 and 109.5 g/L were obtained by immobilised cells for initial sugar concentrations of 200 and 250 g/L for molasses and thick juice, respectively. However, the highest ethanol yields of 31.7 L per 100 kg of molasses and 37.6 L per 100 kg of thick juice were obtained by immobilised cells at an initial sugar concentration of 175 g/L. In the high gravity fermentation process, thick juice resulted in a higher ethanol yield per mass of raw material compared with molasses. This study shows the advantage of immobilised yeast for the efficient production of high gravity bioethanol from thick juice, which was a more favourable raw material than molasses. © 2018 The Institute of Brewing & Distilling     

Synergistic impact of sonication and high hydrostatic pressure on microbial and enzymatic inactivation of apple juice

The combination of innovative, non-thermal technologies for the production of safe and quality fruit juices is a recent trend in food processing. The purpose of this study was to evaluate the effects of combined treatment of ultrasound (US) and high hydrostatic pressure (HHP) on enzymes (polyphenolase, peroxidase and pectinmethylesterase), microorganisms (total plate counts, yeasts and molds) and phenolic compounds (total phenols, flavonoids and flavonols) of apple juice. Moreover, its effects on ascorbic acid, antioxidant capacity and DPPH free radical scavenging activity, color values, pH, soluble solids and titratable acidity were investigated. Fresh apple juice was treated with US (25 kHz and 70% amplitude) at 20 °C for 60 min with subsequent HHP treatment at 250, 350 and 450 MPa for 10 min at room temperature. The results revealed that the combined US-HHP450 treatment caused highest inactivation of enzymes with complete inactivation of total plate counts, yeasts and molds. It also significantly improved the phenolic compounds, ascorbic acid, antioxidant capacity, DPPH free radical scavenging activity and color values. The present results suggest that the combination of US and HHP can act as a potential hurdle to produce safe and high quality apple juice with reduced enzymes and microbial activity and improved nutrition.     

Changes in quality attributes throughout storage of strawberry juice processed by high-intensity pulsed electric fields or heat treatments

The effects of high-intensity pulsed electric field (HIPEF) processing (35 kV/cm for 1700 μs applying 4-μs pulses at 100 Hz in bipolar mode) on color, viscosity and PME and PG activities in strawberry juice were studied and compared to those of heat treatments (90 °C for 60 s or 30 s) through 63 days of storage. L^∗ and viscosity values of the HIPEF-processed juices were higher than those found in the thermally treated. In addition, HIPEF-treated juice exhibited lower 5-(hydroxymethyl)-2-furfural (HMF) concentration and browning index than heat-treated juices throughout storage. On the other hand, HIPEF-treated juice maintained low residual pectin methylesterase (PME) activity (13.1%) for 63 days, whereas in the case of the thermally treated, 22.2 and 48.8% was retained after 60 s and 30 s, respectively. Strawberry juice treated by HIPEF achieved lower residual polygalacturonase (PG) activity (73.3%) than those of heat-processed at 90 °C for 60 s (76.2%) or 30 s (96.8%). Thus, HIPEF could be a feasible alternative to thermal processing to minimize browning and viscosity loss in strawberry juice during storage.     

α-葡聚糖酶在蔗汁澄清工艺中的应用研究

使用细丽毛壳菌发酵生产的α-葡聚糖酶粗酶液在蔗汁中进行试验,试验结果表明,在混合汁中添加粗酶液,用常规的亚硫酸法工艺进行澄清处理,过滤速度与沉降速度均提高了40%,葡聚糖除去率为20%,清汁混浊度降低60%,色值降低10%。在混合汁、清汁与糖浆中添加粗酶液,葡聚糖含量分别减少20%、15%与5%。葡聚糖酶的加入对蔗糖无影响。     

橙汁饮料中的总黄酮含量及其与浑浊稳定性关系研究

为探讨橙汁和橙汁饮料的黄酮含量分布及其与浑浊稳定性的关系,测定了14种橙汁饮料的总黄酮含量、浑浊度及粘度。上清液经过0.45μm膜过滤后黄酮含量与上清液相当。储存一定时间后橙汁浑浊度明显降低,橙汁上清稀释液吸光度A₆60 nm与混匀液的稀释液相比只占9%⁵6%;橙汁饮料经过膜过滤后浑浊度与上清液相比也明显降低。可见,总黄酮含量与饮料的浑浊度变化无关。Spearman秩相关性分析显示,只有100%橙汁混匀液的粘度与浑浊度正相关（p<0.01）,总黄酮含量与浑浊度不相关（p>0.05）。对含橙汁饮料,浑浊稳定性降低不影响总黄酮含量水平。      

酶解生产微胶囊胡萝卜速溶粉工艺研究

胡萝卜在我国大部分省市均有种植,其β-胡萝卜素、维生素、矿物质含量丰富。本文利用微胶囊技术将经酶解处理的胡萝卜加工成一种速溶产品。利用液态果胶酶PectinexUltraSP-L和PectinexSMASHXXL酶解胡萝卜浆,提高了胡萝卜汁的产量。结果表明,果胶酶PectinexUltraSP-L最佳用量(以胡萝卜浆重量计)为0.09ml/kg胡萝卜浆液,PectinexSMASHXXL最佳用量0.18ml/kg胡萝卜浆液,最佳温度50℃,酶解时间2h,酶处理后出汁率能提高到82.8%。加入15%玉米油,3%乳化剂,3%酪朊酸钠和40%糊精微胶囊化后喷雾干燥得到胡萝卜速溶粉。该产品既能直接加水冲调饮用,也能作用一种成分加入到其它配方食品中,应用范围得到了进一步的扩大。     

高压脉冲电场技术在热带果汁加工中的应用前景

高压脉冲电场杀菌技术(简称PEF)是一项新兴的食品非热加工技术,在果蔬汁的加工中已显示出优越性.对国内外近年来关于PEF对果蔬汁中酶的影响、灭菌的效果及对其品质的影响等方面进行综述,分析热带果汁加工中存在的主要问题及PEF技术在热带果汁加工中的应用前景.     

酶技术在果菜汁饮料生产中的应用

讨论了果胶酶、纤维素酶、溶菌酶等十几种酶在水果汁、蔬菜汁饮料加工和储藏中的应用；讨论了酶技术对果菜汁饮料稳定性、营养成分、色泽和风味的影响。