scholarly journals Factors Affecting the Stability of Vitamin C in Tropical Fruit Juices and Nectars

1969 ◽  
Vol 48 (1) ◽  
pp. 1-12
Author(s):  
Abdul R. Rahman ◽  
J. Anziani ◽  
J. R. Cruz-Cay
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Fruit Juices ◽  
Tropical Fruit ◽  
Factors Affecting ◽  
Synthetic Vitamin ◽  
The Stability ◽  
And Storage

Studies were conducted on the effect of certain factors such as temperature, pH, degrees Brix, concentration of vitamin C, and storage in sealed as well as in open containers, on the stability of vitamin C in tropical fruit juices and nectars. They were fortified with different quantities of synthetic vitamin C (1-ascorbic acid) ranging between 10 and 4,000 mg. per 100 ml.

scholarly journals Studies on the Stability of Vitamin C at Elevated Concentrations in Canned Tropical Fruit Juices and Nectars

1969 ◽  
Vol 48 (4) ◽  
pp. 327-336
Author(s):  
Abdul R. Rahman ◽  
J. Anziani ◽  
E. Díaz Negrón
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Room Temperature ◽  
Fruit Juices ◽  
The Other ◽  
Tropical Fruit ◽  
The Stability ◽  
Different Levels

Studies were conducted to determine the stability of vitamin C at elevated concentrations in canned tropical fruit juices and nectars. Canned guava nectar, as well as juices of orange, tomato, and pineapple were fortified with ascorbic acid at seven different levels ranging from the original content present in the samples to about 300 mg. per 100 ml. Half of the samples were stored at room temperature and the other similar half at 100°F. for a period of 6 months. The results indicated that the losses of vitamin C were higher in the samples stored at 100°F. than in those stored at room temperature—regardless of the level of concentration. However, in the guava nectar the percentage of vitamin C destruction was relatively higher at lower concentrations and lower at higher concentrations at both temperatures. No such pattern could be observed in the juices. But the losses of vitamin C in the juices at all levels of concentration ranged below 30 percent at room temperature and below 40 percent at 100°F. This is relatively less than the losses that occurred in the guava nectar.

scholarly journals ELECTROCHEMICAL EVALUATION OF THE STABILITY OF ASCORBIC ACID IN WHEY FROM CHEESE AND RICOTTA

2017 ◽  
Vol 14 (27) ◽  
pp. 51-55
Author(s):  
Lucélia HOEHNE ◽  
Adriano GENNARI ◽  
Eduardo Miranda ETHUR ◽  
Maurício HILGEMANN ◽  
Claucia Fernanda Volken SOUZA ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Cyclic Voltammetry ◽  
Vitamin C ◽  
Antioxidant Capacity ◽  
Electrochemical Techniques ◽  
Factors Affecting ◽  
Oxidative Reactions ◽  
Antioxidant Evaluation ◽  
The Stability ◽  
Electrochemical Evaluation

Ascorbic acid has aroused particular interest due to its antioxidant capacity, which can prevent oxidative reactions. Cyclic voltammetry stands out as one of the main electrochemical techniques for antioxidant evaluation. The cheese and ricotta whey are subproducts of the dairy, and have several components that allow its use in various foods. The enrichment of subproducts with essential substances in food may make its use even more attractive by industries. Therefore, the aim of this study was to evaluate the stability of ascorbic acid in cheese and ricotta whey using cyclic voltammetry. For this, the cheese and ricotta whey were collected from a dairy industry of the Vale do Taquari-RS and were fortified with ascorbic acid and its stability was evaluated according to the electrochemical profiles of the samples. With the data obtained, it was concluded that one of the factors affecting directly the stability of ascorbic acid was the pH, but more studies are needed to evaluate other interfering stability of vitamin C.

Factors affecting measurement of urinary oxalate.

1984 ◽  
Vol 30 (8) ◽  
pp. 1339-1343 ◽  
Author(s):  
B C Mazzachi ◽  
J K Teubner ◽  
R L Ryall
Keyword(s):  
Ascorbic Acid ◽  
Room Temperature ◽  
Alkaline Ph ◽  
Ascorbic Acid Concentration ◽  
Factors Affecting ◽  
The Stability ◽  
Gas Chromatographic Method ◽  
And Storage ◽  
Urine Specimens ◽  
Positive Interference

Abstract Using a gas-chromatographic method, we examined the effects of phosphate concentration, added calcium chloride, and pH on precipitation of oxalate from urine. All three factors are important, but the pH of precipitation is particularly so, especially in the presence of even normal concentrations of ascorbic acid. At pH 8, increases in measured oxalate ranged from 20% at an ascorbic acid concentration of 1 mmol/L to more than 300% at 15 mmol/L. Ascorbic acid is rapidly converted to oxalate at alkaline pH. We also investigated the stability of both untreated and acidified urine containing ascorbic acid during storage for up to one month at -70, -20, and 4 degrees C, and room temperature. After one month, untreated collections were stable at -70 degrees C and acidified collections at -20 and -70 degrees C. We recommend conditions for assay and storage of urine specimens that are to be assayed for oxalate under which positive interference by ascorbic acid is minimized.

scholarly journals The effect of selected substances on the stability of standard solutions in voltammetric analysis of ascorbic acid in fruit juices

2019 ◽  
Vol 17 (1) ◽  
pp. 655-662
Author(s):  
Radosław Kowalski ◽  
Artur Mazurek ◽  
Urszula Pankiewicz ◽  
Marzena Włodarczyk-Stasiak ◽  
Monika Sujka ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Room Temperature ◽  
Nutritive Value ◽  
Fruit Juices ◽  
Optimum Concentration ◽  
Voltammetric Analysis ◽  
The Stability ◽  
Standard Solutions

AbstractThe objective of the study was to identify suitable additives stabilizing standard solutions of ascorbic acid (AA) that would not cause interference in the analytical process with the use of voltammetry in the determination of the AA content in food products. In addition, the effect of various conditions of storage of selected fruit juices and drinks on the concentration of vitamin C was studied. The study demonstrated that AA degradation was inhibited the most effectively by tartaric acid and its optimum concentration was set to 200 mg L-1. Analysis of selected fruit juices stored in various temperature conditions confirmed that an elevation of temperature and extension of the time of storage caused a decrease in the content of vitamin C in the analyzed samples, while closing the packages caused a limitation of the changes in concentration of this vitamin. On the basis of literature data and of the results obtained in the present study it can be concluded that fruit juices should be stored at a temperature lower than room temperature to retain their nutritive value.

scholarly journals The effect of freezing-drying, cloudiness and concentration on the keeping quality of various blackcurrant products

1964 ◽  
Vol 36 (1) ◽  
pp. 161-180
Author(s):  
Taina Kuusi
Keyword(s):  
Ascorbic Acid ◽  
Relevant Literature ◽  
Organoleptic Properties ◽  
Black Currant ◽  
Organoleptic Evaluation ◽  
Freeze Dried ◽  
Juice Concentrate ◽  
The Stability ◽  
And Storage

Experiments have been made in the development of various new black-currant products, such as cloudy juice, juice concentrate and various freeze-dried preparations, along with a study of the effect of these different methods of preparation on the initial quality and storage properties. The quality was assessed from the stability of ascorbic acid and colour, the aroma number, and organoleptic evaluation. Storage lasted up to 8 months. It was established that the cloudiness exercised a slight protective effect on ascorbic acid. However, the instability of the cloud meant that the appearance of the cloudy juice was less attractive than that of the clear juice. No well-founded advantage of the cloudy juice could be demonstrated. Concentration proved less suitable, as there occurred harmful changes in ascorbic acid, colour and organoleptic properties. The freezing-drying method was excellent with respect to ascorbic acid and colour. In contrast, considerable losses in aroma occurred, with consequent weakening of the organoleptic properties. This method would be of advantage only in combination with aroma recovery, and solution of the financial problems involved. The results are discussed in the light of relevant literature.

Factors Affecting Protein Distribution and Structure in a Dried Droplet

2008 ◽  
Author(s):  
Vishard Ragoonanan ◽  
Alptekin Aksan
Keyword(s):  
Surface Flux ◽  
Secondary Flows ◽  
Controlled Environment ◽  
Biological Macromolecules ◽  
Protein Distribution ◽  
Sessile Droplet ◽  
Factors Affecting ◽  
The Stability ◽  
Contact Line Pinning ◽  
And Storage

Convective/diffusive drying of biopreservation solutions that contain biological macromolecules or organisms is widely-utilized, especially in desiccated and vitrified state preservation. Typically, solutions are deposited on a surface as thin films or droplets and are dried in a controlled environment. A typical biopreservation solution contains the biomaterial to be preserved, non-reducing sugars (trehalose, sucrose, etc.), polyols, and salts [1]. There are several factors that affect the overall stabilization and storage efficiency of a biopreservation solution: the properties of the chemicals in the solution, the thermodynamic state of the product to be stabilized, the processing conditions, and the interactions of the solution with the surface it is dried on. For example, during drying of a sessile droplet in a low relative humidity environment, secondary flows form within the droplet due to contact line pinning and non-uniform surface flux. These flows mainly cause accumulation of solutes at the droplet’s periphery [2]. An additional factor is the specific interactions among the constituents of the biopreservation solution, which can affect the stability of the biological material.

Structural and Morphological Characteristics of Hybrid Nanomaterials Type Ascorbic Acid-hydrotalcite Used for Stimulating Salivary Secretion

2018 ◽  
Vol 69 (5) ◽  
pp. 1244-1246
Author(s):  
Georgeta Zegan ◽  
Loredana Golovcencu ◽  
Eduard Radu Cernei ◽  
Elena Mihaela Carausu ◽  
Daniela Anistoroaei
Keyword(s):  
Drug Delivery ◽  
Ascorbic Acid ◽  
Vitamin C ◽  
Morphological Analysis ◽  
Interlayer Space ◽  
Morphological Characteristics ◽  
Salivary Secretion ◽  
Morphological Characterization ◽  
Hybrid Nanomaterial ◽  
The Stability

A new hybrid nanomaterial type vitamin C/ZnAl-hydrotalcite, acting as drug delivery system for ascorbic acid, was developed in order to use it for stimulating salivary secretion. The synthesis of this nanomaterial was achieved using a simple coprecipitation method for intercalation of ascorbate anions in the ZnAl-hydrotalcite gallery. The stability of vitamin C was significantly increased after its incorporation into the interlayer space. Structural and morphological characterization techniques revealed an alteration of the pristine nanomaterial type ZnAl-hydrotalcite when vitamin C was loaded in its matrix. Structural and morphological analysis showed that ascorbate anions were intercalated in the interlayer of ZnAl-hydrotalcite having no effect on the hydroxide lattice of hydrotalcite, so this new nanomaterial can be used for the intended purpose.

The Effect of Storage Method on the Vitamin C Content in Some Tropical Fruit Juices

2009 ◽  
Vol 4 (2) ◽  
pp. 79-84 ◽  
Author(s):  
V.O. Ajibola ◽  
O.A. Babatunde ◽  
S. Suleiman
Keyword(s):  
Vitamin C ◽  
Fruit Juices ◽  
Tropical Fruit ◽  
Storage Method

scholarly journals Strawberry Puree Functionalized with Natural Hydroxytyrosol: Effects on Vitamin C and Antioxidant Activity

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5829
Author(s):  
Alejandra Bermúdez-Oria ◽  
Yougourthane Bouchal ◽  
África Fernández-Prior ◽  
Blanca Vioque ◽  
Juan Fernández-Bolaños
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Vitamin C ◽  
Functional Food ◽  
Dehydroascorbic Acid ◽  
Model System ◽  
Human Diet ◽  
Low Concentrations ◽  
High Concentrations ◽  
The Stability

The natural antioxidant hydroxytyrosol (HT) was used to functionalize a strawberry puree. The effect of the antioxidant on the stability of the two bioactive forms of vitamin C (ascorbic acid-AA and dehydroascorbic acid-DHAA) in strawberry puree stored at 4 °C, compared with the effect on a model system of AA in water, was investigated. In the absence of HT, the concentration of vitamin C in strawberry puree decreased but not in the model system. Low concentrations of HT in strawberry puree (0.05 and 0.1 mg HT/g puree) stabilized vitamin C and improved its antioxidant activity. However, at high concentrations of HT (from 0.5 mg HT/g puree), although the antioxidant activity improved, degradation of vitamin C occurred. Therefore, the concentration of HT used to obtain a functionalized strawberry puree it is very important. An adequate concentration increases the antioxidant activity and protects vitamin C from degradation, developing a functional food. However, an inadequate concentration of HT affects the vitamin C content, which is essential for the human diet because it cannot be biosynthetized by the organism.

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