Characteristics Of Juice Research Articles

Microbial Analysis of Vended Fruit Juices and Sauces Consumed in Restaurants in Narsingdi City, Bangladesh

Fresh fruit juices from cafes and restaurants are a popular beverage in Narsingdi city of Bangladesh during summer season. Food-borne outbreaks may arise from them since harmful germs from the unsanitary surroundings of the food preparation area easily infect them. The purpose of the current study was to identify the microbiological characteristics of various fruit juices and sauces consumed in different cafes and restaurants in Narsingdi City, Bangladesh. The detection of total viable bacterial load, total fungi count, coliforms, and some other pathogenic bacteria was checked in a total of thirty-nine juice and sauce samples, specifically of six categories of juices (orange, lemon, pineapple, sugarcane, papaya, and apple) and three categories of sauces (tomato sauce, mustard sauce, and tamarind sauce). Total viable bacteria in these samples ranged from 104 to 108 CFU/mL. Sixty percent of the samples had total coliforms (including Escherichia coli and Klebsiella spp.), all of which alarmingly exceeded the conventional bacteriological limits (1.0×104 CFU/mL) advised for fruit juices. Vibrio spp., Salmonella spp., and Staphylococcus spp. were identified as harmful microorganisms. Standard biochemical, microscopic, and cultural assays were used to identify each of these bacterial isolates. Sulfomethoxazole-trimethoprim, Ciprofloxacin, Tetracycline, Nalidixic Acid, Gentamicin, Ceftriazone, Ampicillin, and Netilmicin were among the drugs against which the isolates showed variable levels of drug resistance. The microbiological evaluation of these well-known ready-to-drink goods is therefore constantly required; otherwise, they could pose health risks.

Chemical and Sensory Evaluation of Blackberry (Rubus sp.) Juice Concentrated by Reverse Osmosis and Osmotic Evaporation.

Blackberry can be considered a source of phenolic compounds with antioxidant properties, especially anthocyanins, which are responsible for the attractive color of the juice. However, blackberry juice quality can be reduced under severe heat treatments, resulting in darkened color and altered taste. Membrane separation processes are an alternative for the clarification and concentration of fruit juices, with advantages as the maintenance of the nutritional, sensory, and functional characteristics of the product. The aim of this work was to evaluate the effect of membrane concentration on the physicochemical and sensory characteristics of blackberry juice. The juice was first clarified by an enzymatic treatment associated with microfiltration and then concentrated by reverse osmosis and osmotic evaporation. Samples were analyzed for pH, titratable acidity, soluble and total solids, phenolic content, antioxidant activity, and total anthocyanins. The concentrated juices were then reconstituted for sensory evaluation. It was verified that reverse osmosis and osmotic evaporation resulted in juices with total solid concentrations of 29 and 53 g∙100 g-1, respectively, with slight differences in pH and acidity. Some phenolic compounds were lost during processing. The concentration of anthocyanins and the antioxidant capacity of the osmotic evaporation-concentrated juice increased 6.2 and 7.7 times, respectively, compared to the initial juice. Regarding sensory analysis, the juices concentrated by RO and EO presented acceptance percentages (scores between 6 and 9) of 58% and 55%, respectively. Consumers described them as "good appearance", "refreshing", "tasty", "sweet", or "with ideal sweetness", in agreement with the high acceptance scores (6.2 and 6.9, respectively).

Effect of conventional blanching of apple slices on quality characteristics of apple juice after storage at 4oC for 30 days.

???? ??? ??????? ??? ??????? ???? ?????? ?? ???? ?????? ?????? ???? ?? ???????? ??????. ??????? ???????? ???????? ??? ????? ?????? ???????? ??? ???? ????? (4)????? ???? (30) ???? ????????? ?? ???? ??????? ??? ???????? ?????? ????? ????? ????? ??????????? ???????? ?? ???? ?????? ?? ????????? ???????? ?? ??? ???? PPO (????????? ????????). ???? ?????? ???????? ?? ??? ??????? ???????? ???? ??? ??????? ??: ?????? ???????? ???????? ??????? ???????? ???????? ?????? ??? ??????????? ?????? ????????? ?????? ????? ???????? ?? ??? ???? ?????? ???????? ???????? ????? ???? ?? ????? ??????? ?? ?????????. ???? ???? ???? ?????????? ????? ?????? ????????? ????? ????? ????? ???????? ?????? ??????? ?????????? ?????? ?? ?????? ??? ????? ???? ???????? ??? ??? ???? ???????. ?? ????? ?? ????? ???????.

Effects of different lactic acid bacteria on the physicochemical properties, functional characteristics and metabolic characteristics of fermented hawthorn juice

Effects of different lactic acid bacteria on the physicochemical properties, functional characteristics and metabolic characteristics of fermented hawthorn juice

Ultra-high-pressure homogenization in chicory root juice production

The demand for freshly squeezed natural fruit juices has increased in recent years, however their shelf life is quite short. Thermal processes applied to extend the shelf life of such products and increase their storage stability cause significant losses in color and other sensory properties, depending on the temperature applied. Therefore, the preference for high-pressure homogenization as an alternative to thermal processes is on the rise. We aimed to determine effects of ultra-high-pressure homogenization and production stages on some quality properties of chicory root juice. Ultra-high-pressure homogenization was applied at the pressure levels of 0 (Control), 50, 100, 150, and 200 MPA. The samples also included juice after homogenization with an ULTRA-TURRAX disperser and after a water bath. Ultra-high-pressure homogenization affected such quality characteristics of chicory root juice as total soluble solids (p < 0.01), pH (p < 0.01), L* (p < 0.01), a* (p < 0.01), b* (p < 0.01), a*/b* (p < 0.01), chroma (p < 0.01), hue angle (p < 0.01), and total color difference ΔE (p < 0.01). Higher levels of ultra-high-pressure homogenization pressure increased pH (p < 0.05), a* values (p < 0.05), and the a/b* ratio (p < 0.05) but reduced L* (p < 0.05), b* (p < 0.05), chroma (p < 0.05), and hue angle (p < 0.05) values of the juice samples. Thus, the use of ultra-high-pressure homogenization (100 and 200 MPa) contributed to improving the total soluble solids and redness values of chicory root juice. Our study showed that the ultra-high-pressure homogenization process improved the quality of chicory root juice.

Sensory approach to added sugar reduction in strawberry juices using fuyu persimmon

The aim of this study was to produce strawberry juice with reduced added sugar content, use the alternative natural sweetness of persimmon, and evaluate its physicochemical and sensory characteristics. Five different strawberry juice formulations were prepared with a 25% reduction in the added sucrose content with 0, 12.5, 25, 37.5, and 50% added persimmon pulp. Color, soluble solids, pH, and titratable acidity were evaluated, and CATA and acceptance sensory tests were performed with 100 consumers. In general, adding persimmon pulp to strawberry juice significantly affects both its physicochemical and sensory properties. From a physicochemical point of view, as the persimmon content increased, the strawberry juice tended to turn from red to orange, and there was an increase in soluble solids content and pH, as well as a decrease in acidity. From a sensory point of view, changes in sensory profile and product acceptability were also observed. However, persimmon showed potential as a natural sweetener in strawberry juice to reduce added sugar. Formulations with lower levels of persimmon pulp (12.5 and 25%) showed promise as these formulations maintained the valued sensory characteristics of strawberry juice and used the natural sweetness of persimmon to reduce added sugars, making them healthier beverage alternatives.

Improving sucrose extraction technology when processing substandard raw materials

Long-term storage of large volumes of sugar beets, due to an increase in the production capacity of enterprises, leads to a decrease in the technological quality of raw materials. Unstable weather conditions cause freezing and subsequent thawing, which destroys beet tissue, increasing its accessibility to microorganisms. Processing of substandard raw materials is accompanied by the use of a whole range of bactericidal drugs at different stages of production, to which resistance of the accompanying microflora develops over time. To reduce the degree of infection of intermediate products at the production site, it is proposed to use a bactericidal preparation based on the sodium salt of dichloroisocyanuric acid (DCCN), which can be introduced into the extractant before feeding it into the diffusion apparatus. The influence of the quantity, concentration of the DCCN solution and the temperature of the extractant on the qualitative characteristics of diffusion and purified juices was experimentally established. A positive effect of DCN was revealed during the processing of beets contaminated with Leuconostoc mesenteroides. Using mathematical modeling methods, regression dependencies were obtained that reflect the relationship between process parameters and quality characteristics of juices. The optimal parameters for the use of DCCN in preparing the extractant for the diffusion process have been established: temperature 65 °C, concentration of the DCCN solution 0.05 %, its amount 15 %. This drug can also be used at the stages of storing sugar beets, processing beet chips before extraction, and disinfecting equipment.

Cold plasma processing of kiwifruit juice: Effect on physicochemical, nutritional, microstructure, rheological properties and sensory attributes.

This study aimed to compare the untreated, cold plasma (CP)-optimized (30 kV/5 mm/6.7 min), CP-extreme (30 kV/2 mm/10 min), and thermally treated (TT) (90 ℃/5 min) kiwifruit juices based on the physicochemical (pH, total soluble solids (TSS), titratable acidity (TA), total color change (ΔE)), physical (particle size and rheology), microstructure (optical microscope), bioactive compounds (polyphenol, ascorbic acid, and sugar compounds), and sensory characteristics of kiwifruit juice. The pH, TSS, and TA were not significantly affected in CP and TT juice, whereas the ΔE (6.52) of TT juice lies in the range of "greatly visible." The microstructure characteristics of juice significantly changed after CP and thermal treatment. The cell and tissue disruption in CP-extreme and thermally treated juice was more than CP-optimized. The particle size of juice decreased irrespective of treatment, but the span value of CP-optimized juice was the lowest. Further, the CP treatment showed a lower consistency index, apparent viscosity, and pseudoplasticity of juice than the thermal treatment. The CP-treated juice retained bioactive and nutritional attributes more than thermally treated juice. The CP-optimized, CP-extreme, and thermal treatment reduced the sucrose content by 54, 55, and 23%, while the fructose and glucose content were increased by 17, 12, & 93%, and 17, 11 & 99%, respectively. Among the CP-treated juice, CP-optimized (71.36 mg/100g) contained a higher amount of ascorbic acid than the CP-extreme (64.36 mg/100g). Based on the similarity values in the fuzzy logic analysis, the sensory attributes of CP-optimized treated juice were superior to CP-extreme and thermal treated. PRACTICAL APPLICATION: In this era, non-thermal processing techniques are trending for retaining the nutrition and stability of juice. The old plasma (CP)-treated kiwifruit juice had better nutritional, bioactive compounds, and sensory attributes than the thermally treated juice. Further, the CP-treated juice had higher flowability and lower viscosity, making it ideal for juice processing. The conclusions drawn suggest that CP processing is a better alternative for processing kiwifruit juice than thermal processing.

Potential Utilization of Defective Fruit Juice Products for Black Soldier Fly Cultivation to Reduce Waste Generation in the Beverage Industry

The waste of fruit juice and tea defective products has organic content that conventionally has the potential to be utilized as a medium or place for maggot growth, but until now it has not been equipped with supporting scientific studies. Therefore, the objectives of the study are: 1) Assessing the characteristics of fruit juice and tea product waste, 2) Assessing the effectiveness of maggot in reducing fruit juice and tea product waste. This research is experimental in nature using variations in the composition of fruit juice and tea product waste as a source of nutrition for maggot which is carried out for 12 days. This variation uses the Complete Randomized Design method with 3 (three) treatments, namely variations in the composition of 60% tea + 40% fruit juice waste (S1), 50% tea + 50% fruit juice waste (S2), and 40% tea + 60% fruit juice waste (S3) in duplo. In addition, this study was completed with a control treatment. The results showed that the characteristics of fruit juice and tea waste containing protein (3.78-4.59%), fat (0.90-1.31%), carbohydrates (28.15-29.15%), crude fiber (2.42-3.12%) can be used as maggot cultivation media. The highest protein and crude fiber contents were found in the S3 composition waste at 4.59% and 3.12%. Maggot cultivation results that showed the highest fat and carbohydrate content were found in S1 composition waste at 1.31% and 29.15%. The recommended composition variation is S1 composition with the highest substrate consumption value and waste reduction index of 57.47% and 20.06%.

QUALITY AND SAFETY PARAMETERS BEFORE AND AFTER PASTEURIZATION OF APPLE JUICE

The research was carried out in September (2023) on the premises of the “Kosovo Agricultural Institute” in the city of Peja. The purpose of this research was to show the influence of pasteurization on the physical, chemical, and organoleptic characteristics of apple juice. During the study, several analyses of the physical, chemical, and sensory parameters of apple juice were carried out. The parameters that have been realized include: °Brix value, Total acidity, Vitamin C, pH and SO2, sensory parameters: aroma, color, taste, and clarity-turbidity. The purpose of this research is the importance of knowing the influence of some parameters on apple juice before and after pasteurization. Pasteurization of apple juice is of great importance due to various factors related to food safety, storage, and consumer health. In the analysis of sensory parameters, the juice before pasteurization had a milder and lighter aroma, had a lighter yellow color, tasted less sweet, less fresh, and had low acidity. Clarity was present but contained some turbidity. In the analysis of sensory parameters, the evaluation of physicochemical parameters and sensory parameters should contribute to valuable knowledge on the physicochemical transformations caused by pasteurization in apple juice. Understanding these changes is very important for maintaining product quality and ensuring customer satisfaction. The study provides a basis for optimizing pasteurization processes to minimize unwanted changes in juice characteristics.

Co-fermentation of Lactiplantibacillus and Streptococcusccus enriches the key-contribution volatile and non-volatile components of jujube juice

Lactic acid bacteria (LAB) fermentation can enhance the quality and flavor characteristics of fruit juice. Herein, the impact of individual Lactiplantibacillus plantarum subsp. plantarum (L. plantarum) or Streptococcus thermophilus (S. thermophilus) and co-fermentation of them on jujube juice was compared, and their quality characteristics, volatile and non-volatile compounds were investigated. The results showed that the co-fermentation of selected LAB strains effectively improved the quality of fermented jujube juice (FJJ) as expected, and the types and content of volatile organic compounds (VOCs) increased in FJJs. Among them, the co-fermented sample posed relatively high content of aroma-active compounds with OAV ≥1 (nonanal, decanal, etc), benzaldehyde and acids compared with others, contributing to a more attractive and pleasant flavor. Moreover, non-targeted metabolomic analysis identified 114 and 79 differential metabolites (DMs) between co-fermented and L. plantarum fermented or S. thermophilus fermented samples, respectively. Notably, carboxylic acids and their derivative metabolites as well as organic acids were the crucial components affecting the quality of FJJ. Furthermore, metabolic pathways of DMs of different samples were predominantly enriched in “biosynthesis” and “metabolism”, such as aline, leucine, and isoleucine biosynthesis pathway. Therefore, co-fermentation could enrich the acids, essential amino acid, and VOCs, thereby improving its quality and flavor characteristics. The correlation analysis revealed that most of key VOCs were positively or negatively correlated with D-galacturonate, indicating the importance of D-galactose pathway. Thus, this study provided a theoretical foundation for enhancing the quality and flavor of jujube juice through LAB co-fermentation, offering valuable insights for improving the juice processing.

Deacidification of concentrated cranberry juice by electrodialysis with bipolar membranes: A feasibility and comprehensive study

Electrodialysis with bipolar membranes (EDBM) recently shown promising outcomes as a novel green technology to deacidify cranberry juice without altering its polyphenolic compounds, responsible for many health benefits. The performance of EDBM depends on many factors, including the concentration of the treated solution. While previous research only deacidified cranberry juice by EDBM with concentration of 8°B, the present study aimed to assess the physicochemical attributes of more concentrated juices and the effect of using specific ones (5°B, 15°B, 25°B and 35°B) during EDBM on deacidification and electrodialytic parameters evolution. Optimal juice characteristics for EDBM use (viscosity, conductivity) were exhibited at 25°B. The 4 selected juice concentrations were successfully deacidified by 39.0 ± 2.5 % but with significantly different process times (from 46 ± 2 min to 471 ± 16 min). Extended treatment duration led to a slight loss in anthocyanins and proanthocyanidins, likely due to increased polyphenols-membranes interactions, which contributed to system resistance growth. However, the reduction in citric (32 ± 3 %) and malic (61 ± 4 %) acids remained consistent, regardless of the juice concentration. This work confirmed the feasibility of producing a concentrated and deacidified cranberry juice by EDBM, that can represent a great potential to the functional food market.

Enhancement of nutritional characteristics of Tartary buckwheat (Fagopyrum tataricum) sprouts, passion and pineapple juice fermented by yeast (Saccharomyces cerevisiae) and Lactobacillus plantarum

Enhancement of nutritional characteristics of Tartary buckwheat (Fagopyrum tataricum) sprouts, passion and pineapple juice fermented by yeast (Saccharomyces cerevisiae) and Lactobacillus plantarum

Determining the impact of pre-pressing pretreatments applied to sugarcane on the aroma compounds and quality characteristics of sugarcane juice.

The study examined the effects of three pretreatments, blanching (5, 10, and 30min), ultrasound (15, 20, and 30min), and steam blanching (10, 20, and 30min) on sugarcane, assessing their impact on sugarcane juice quality parameters and aroma compounds. The control had the highest soluble solid content, while the ultrasound-15min (US-15min)-treated sample had the lowest, affecting pH, total acidity, and color values significantly. Color analysis showed lower L* values and less greenish tones in treated samples. The implemented pretreatments effectively reduce the browning index, with the US-20min treatment showing the most significant reduction compared to the control sample. All pretreatments deactivated polyphenol oxidase. Carbon isotope analysis yielded significant results. Principal component analysis and hierarchical clustering linked 1,1-diphenyl-2-picrylhydrazyl (DPPH) with 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 5-hydroxymethyl furfural (HMF) with total phenolic content. The study also highlights significant variations in aroma compound profiles among pretreated sugarcane juice samples, with blanching for 10 min showing notable increases in specific compounds like 2-heptanone and nonanol. Hierarchical clustering showed similarities between blanching-30min and US-30min, contrasting with the control. Blanching-10min had a positive impact on sugarcane juice quality. In conclusion, the study emphasized how pretreatments affect physicochemical properties and aroma compounds in sugarcane juice. PRACTICAL APPLICATION: The research findings suggest that blanching and ultrasound pretreatments can be used by the food industry to improve sugarcane juice quality by reducing browning, enhancing color, and altering aroma profiles. These pretreatments could extend the shelf life and appeal of sugarcane juice, making it more attractive to consumers while maintaining its nutritional properties.

Yield Performance and Quality Assessment of Brazilian Hybrid Grapes Influenced by Rootstocks and Training Systems

The choice of training system impacts the architecture and physiological characteristics of grapevines, affecting grape production and quality. Continuous studies are necessary to optimize viticulture production in Brazil. This study aimed to evaluate the effects of rootstocks and different training systems on the production and quality of ‘IAC 138-22 Máximo’ and ‘BRS Violeta’ grapevines for juice and wine. The experiment was conducted over two productive cycles (2019/2020 and 2020/2021) in an experimental vineyard at the Advanced Center for Fruit Research as part of the Agronomic Institute (IAC), in Jundiaí, São Paulo, Brazil (23°06′ S, 46°55′ W, and 745 m altitude). For each cultivar, a randomized block design in a 2 × 2 factorial scheme was used, with two rootstocks (‘IAC 766 Campinas’ and 106-8 ‘Mgt’) and two training systems (low and high trellises), with five blocks of three plants per experimental plot. In both cycles, the gas exchange and grapevine production, the chemical characteristics of the grape juice (must), and the chemical compounds in the berry skins were evaluated. The rootstocks and training systems influenced the variables evaluated in both cultivars, with the high trellis system providing the best results. This approach increased the photosynthetic rate, improved water-use efficiency, elevated grapevine production, and enhanced fruit quality. Therefore, its use is recommended for training grapevines. Regarding rootstocks, the best scion–rootstock affinity was found between hybrid grapevines and ‘IAC 766 Campinas’.

A comparative analysis of red and white dragon fruit pulp and juice characteristics.

To ascertain their potential applications in the food industry, dragon fruit varieties, namely H. undatus and H. polyrhizus, were thoroughly analyzed for their physical, nutritional, and phytochemical properties. The focus was on pulp and juice, emphasizing color, mineral content, proximate analysis, and phytochemical constituents. Red flesh dragon fruit displayed a bright pink color, a slightly smaller length (9.1 cm), and a larger diameter (8.3 cm) compared to white flesh dragon fruit (9.9 cm length, 7.53 cm diameter). Red flesh dragon fruit also exhibited higher circumference and weight. White flesh dragon fruit demonstrated superior juice yield (36.23 %) compared to red flesh dragon fruit (35.28 %). Red flesh dragon fruit had higher levels of total sugar (8.45 %), protein (1.36 %), and ascorbic acid (19.83 mg/100g) in its pulp. It also showed elevated mineral content of calcium, magnesium, and phosphorus. Conversely, white flesh dragon fruit had higher fat content (0.65 %) and carbohydrate content (9.76 %) in its pulp. White flesh dragon fruit displayed brighter color characteristics with higher L*, a*, and b* values. Phytochemical analysis revealed the presence of betacyanin in red flesh dragon fruit (30.87 mg/100g) but not in white flesh dragon fruit. Red flesh dragon fruit exhibited significantly higher total phenolic content in pulp (49.67 mg GA/100g) and juice (41.25 mg GA/100g) than white flesh dragon fruit. These findings highlight substantial differences (P < lt; 0.05) between red and white flesh dragon fruit in physical, nutritional, and phytochemical aspects, offering valuable insights for their incorporation into diverse food products, such as beverages and ice cream.

Phytochemical and Flavor Characteristics of Mulberry Juice Fermented with Lactiplantibacillus plantarum BXM2.

Fermentation of mulberry juice not only improves its shelf life, but also effectively enhances their flavor and nutritional quality. This study elucidated the phytochemical and flavor characteristics of mulberry juice fermented with Lactiplantibacillus plantarum BXM2, originally isolated from naturally fermented fruit beverage, through widely targeted metabolomics. The fermentation produced the unique flavor of fermented juice and decreased the pH from 4.15 to 3.19. The metabolomic analysis detected 907 non-volatile metabolites, from which 359 significantly different non-volatile metabolites (up 238, down 121) were screened out. Among 731 identified volatile metabolites, 26 flavor substances were the major contributors to the flavor differences between fermented and unfermented mulberry juices. It is hypothesized that lipid metabolism and amino acid catabolism are crucial pathways for the flavor enhancement of mulberry juice fermented with L. plantarum BXM2. Meanwhile, significant increases of the contents of a variety of bioactive substances, such as indole-3-lactic acid, octadeca-9,12,15-trienoic acid, di-/tri-peptides, etc., conferred additional health potential to BXM2-fermented mulberry juice.

Compositional Characteristics of Currant Juices Prepared by Different Processes and Other Selected Currant Products

The quality of black/red currant products, which are valuable components of a healthy diet, depends on many aspects, e.g., natural variability, climatic conditions, degree of ripeness, processing technology, and recipe. The aim of the study was to assess the effect of the harvest year (2020 and 2021) and different processes (with or without prepress enzymatic treatment) on the chemical composition of 38 laboratory-prepared black/red currant (BC/RC) juices and to compare them with 19 selected commercial products, using 20 compositional and quality markers. Significant differences (p < 0.01) were observed for BC in sucrose, Dp-3-glu, and Cy-3-glu content within the different processes, as well as fructose and ascorbic acid content within the harvest year (p < 0.05). The greatest differences between BC and RC juices were observed in ascorbic acid content (1567 mg/kg in BC and 261 mg/kg in RC), citric acid content (34.6 g/kg in BC and 23.2 g/kg in RC), and in the anthocyanin profile. The major anthocyanins of the currant products were identified as Dp-3-rut (39.1–50.4%), Cy-3-rut (30.1–39.1%), Cy-3-glu (3.6–18.2%), and Dp-3-glu (9.4–13.5%) in BC and Cy-3-glu (59.3–67.2%) and Cy-3-rut (14.2–19.8%) in RC. The chemical composition of commercial products was found to be highly variable and dependent on the recipe used.

Quality Evaluation of Bergamot Juice Produced in Different Areas of Calabria Region.

Citrus fruits are extensively cultivated worldwide, with Italy and Spain being major producers. In Southern Italy, particularly in Reggio Calabria, a typical citrus fruit is produced, namely, bergamot (Citrus bergamia Risso et Poiteau), known for its mysterious origins and exceptional quality essential oil protected by the EU's PDO (Protected Designation of Origin) designation. Despite historical challenges, bergamot has regained prominence for its nutraceutical potential, especially its flavonoid-rich juice, offering significant health benefits. However, little attention has been paid to understanding the qualitative and quantitative differences of bergamot juice in Calabrian production areas. For this reason, this work aims to investigate the quality characteristics of bergamot juice produced in different areas of Calabria sites. The results showed the best quality attributes of bergamot fruits harvested in the PDO area. In particular, higher levels of total soluble solids, stable acidity, and higher juice were found. In addition, higher contents of ascorbic and citric acids, which are nutritionally valuable and tasteful, were found. The phenolic profile, characterized by the key compounds of bergamot, highlighted the better nutraceutical potential of the fruit grown in the PDO area.

Effect of pasteurization time and temperature on the physico-biochemical properties of soursop (Annona muricata L.) juice

This study aimed to determine the effect of pasteurization time and temperature on soursop juice characteristics. Soursop (Anonna muricata L.), a climacteric fruit, is a high source of natural antioxidants and contains polyphenol oxidase (PPO) enzyme, which causes browning and can reduce the phenol content in fruit which can reduce antioxidant activity. The pasteurization process was carried out to inactivate PPO in soursop juice production. Soursop juice was prepared from soursop fruit pulp pasteurized at temperatures (56, 62, 68, 74, and 80 oC) for various pasteurization times (5, 10, and 15 minutes). Time and temperature of pasteurization had a significant effect (ρ < 0.05) on physical characteristics (Total Soluble Solid/TSS, viscosity, pH, and colour), polyphenol oxidase enzyme activity, antioxidant activity, and microbial population. Pasteurization at 62 ˚C for 5 minutes can maintain antioxidant activity with the greatest total phenol of 85.45 ± 3.5 mg GAE/100 g, total flavonoid of 71.38 ± 6.9 mg QE/100 g, and antioxidant activity of 76.91 ± 0, 33%. Pasteurization at 80 ˚C for 15 minutes can reduce the total number of bacteria from 350 ± 24 CFU/mL to 54 ± 22 CFU/mL, which has a TSS value of 13.73 ˚brix, viscosity of 928.67 mPa, pH of 4.40, a total colour change of 0.556, and has the lowest PPO enzyme specific activity of 0.0005 U/mg with enzyme inactivation of 93%.