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

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.

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1568
Author(s):  
Rebecca R. Milczarek ◽  
Carl W. Olsen ◽  
Ivana Sedej

Watermelon (Citrullus lanatus) juice is known for its refreshing flavor, but its high perishability limits its availability throughout the year. Watermelon juice concentrate has extended shelf-life and lower transportation and storage costs, but the conventional thermal evaporation process for concentrating juice degrades the nutritional components and sensory quality of the product. Thus, in this work, a large-scale, non-thermal forward osmosis (FO) process was used to concentrate fresh watermelon juice up to 65°Brix. The FO concentrate was compared to thermal concentrate and fresh juices, and to commercially available refrigerated watermelon juices, in terms of lycopene and citrulline content, total soluble phenolics, antioxidant activity, and sensory properties. The FO concentrate had statistically similar (p < 0.05) levels of all the nutrients of interest except antioxidant activity, when compared to the thermal concentrate. The reconstituted FO concentrate maintained the same antioxidant activity as the raw source juice, which was 45% higher than that of the reconstituted thermal concentrate. Sensory results showed that reconstituted FO concentrate resulted in highly liked juice, and it outperformed the reconstituted thermal concentrate in the sensory hedonic rating. This work demonstrates the possibility to produce a high-quality watermelon juice concentrate by forward osmosis.


2020 ◽  
Vol 65 (12) ◽  
pp. 778-784
Author(s):  
D. P. Piskunov ◽  
L. A. Danilova ◽  
A. S. Pushkin ◽  
S. A. Rukavishnikova

A literature review in the article presents an analysis of the influence of endogenous and exogenous factors on quality of preanalytical phase of laboratory testing. The review shows significance of external and internal factors influencing blood samples at preanalytical phase of laboratory testing. Among the exogenous factors considered: phlebotomy, test tubes for samples, transportation and storage. A number of factors exist at this phase that significantly affect test results. We examined these aspects of phlebotomy process: staff training, disinfectant contamination, needle diameter, needle material contamination. The review considers possible contamination with tube components and the importance of choosing the right anticoagulants and excipients. Transportation and storage of biological samples can be a source of errors at the preanalytical phase of laboratory testing. We analyzed the problem of determining the stability of analytes during storage and aspects of transportation samples by modern means. Among the endogenous factors considered: hemolysis, lipemia, icterricity, cell metabolism.. Hemolysis is one of the most frequent consequences of errors at the preanalytical phase. We analyzed importance of choosing a method for identifying hemolized tubes and the heterogeneity of bias results on different analytical systems. The review shows contribution of various classes of lipoproteins to turbidity of sample, possible preanalytical errors and impact on analytical tests. We examined possible effects of high bilirubin concentrations on analyte measurements. In the review, we also examined metabolism of some cells and its effect on samples.


2012 ◽  
Vol 92 (5) ◽  
pp. 901-912 ◽  
Author(s):  
Olivier M. Stoffyn ◽  
Rong Tsao ◽  
Ronghua Liu ◽  
David J. Wolyn

Stoffyn, O. M., Tsao, R., Liu, R. and Wolyn, D. J. 2012. The effects of environment and storage on rutin concentration in two asparagus cultivars grown in southern Ontario. Can. J. Plant Sci. 92: 901–912. Flavonoids have been shown to have many human health benefits due to their antioxidant activity. Concentration of rutin, the primary antioxidant in asparagus spears, can vary significantly with cultivar, location and season. Assessment of rutin in cultivars across locations throughout the harvest season in Southern Ontario, as well as in stored asparagus, is important for defining the potential benefits of consuming local asparagus. The objectives of this research were to determine the effects of cultivar, harvest time, location, spear diameter and part, and storage of fresh spears and freeze-dried flour on rutin concentration. Sampling date over the 6-wk harvest season and location did not significantly affect rutin concentration in either of the two cultivars tested. Rutin concentration was inversely related to air temperature before harvest and spear diameter, and for any given diameter, was highest in the tops of spears and decreased towards the bottom, in both cultivars. Soil temperatures before harvest were not correlated with rutin concentrations. Storage of fresh spears at 4°C, or freeze-dried flour at varying temperatures, did not affect concentration. The stability of rutin concentration throughout the harvest season, across locations and in stored products suggests predictable antioxidant levels in Ontario-grown asparagus.


1991 ◽  
Vol 56 (5) ◽  
pp. 1388-1392 ◽  
Author(s):  
K. PÄÄKKÖNEN ◽  
M. MATTILA

2017 ◽  
Vol 30 (3) ◽  
pp. 224
Author(s):  
Nuno Durão ◽  
José Amarante

Introduction: Prognathism is a common skeletal facial abnormality, associated with class III malocclusion, often with repercussions in quality of life. In addition to orthodontic treatment, sagittal split ramus osteotomy is the most common technique for its correction, and segment osteosynthesis is an important element of the post-surgical outcome.Materials and Methods: A search for relevant literature was conducted in the PubMed/MEDLINE database and in other relevant sources.Results: The stability of different fixation methods, their repercussions on inferior alveolar nerve lesions, and the type of material are among the most researched subjects.Discussion: Recent research about the type of osteosynthesis applied in the sagittal split ramus osteotomy for mandibular setback is discussed.Conclusion: Miniplates appear to be the better option for fixation of sagittal split osteotomy for mandibular setback. Bioabsorbable osteosynthesis may be an acceptable alternative to titanium.


2010 ◽  
Vol 8 (1) ◽  
pp. 26
Author(s):  
E P Samodra ◽  
H Cahyono

<p>The research was conducted to investigate the effect of soaking meat of Peranakan Ongole cattle with ascorbic acid and storage duration at 50C on physical quality of meat. The experiment was done in Complete Randomised Design by factorial 3 x 3. First factor was ascorbic acid with 3 levels (0%, 5%, 1%), and second factor is storage duration with 3 levels (0, 5, and 6 days). Variables that were measured: tenderness, cooking loss, water holding capacity and pH. Data were analyzed by variance analysis and the significant result were tested by Duncan’s test. Tenderness average for ascorbic acid ranging between 1,60 – 1,62 kg/cm2, and for storage duration was increased from 1,83 to 1,38 kg/cm2. Cooking loss average for ascorbat acid ranged from 43,33 to 44,89%, and for storage duration increased from 40,00 to 47,00%. Water holding capacity average for ascorbic acid ranging between 32,88 – 33,65%, but for storage duration decreased from 34,61 to 32,32%. The pH average for ascorbic acid ranging from 5,99 to 6,16, and increased for storage duration from 6,43 to 5,84. It can be concluded that physical quality of beef cattle was not affected<br />bay ascorbic acid up to 1%, but was significantly decreased by storage duration (p&lt;0,05).</p><p>Key words: Pernakan Ongole meat, ascorbat acid, storage time</p>


1966 ◽  
Vol 38 (3) ◽  
pp. 150-161
Author(s):  
Taina Kuusi

A study has been made of the quality properties of 12 home-grown varieties of black-currant. Samples were obtained from six localities over a period of three years. The properties studied consisted of the aroma number, the organoleptic evaluation, and the degree of ripeness. As regards aroma number, great variations were noted between the samples. The influence of variety was rather slight. In general, the aroma numbers were higher when the summer was cool and the growing locality more to the north, probably by reason of the losses of volatile reducing substances at higher temperatures. The utility of the aroma number in characterization of quality seems limited in scope. Smell and taste were taken as the main criteria in the organoleptic evaluation. The differences between the varieties were not very great, but in any event a relatively consistent sequence was discovered. Consideration is given to some factors which influence organoleptic properties. The degree of ripeness of the samples, and the effect of this factor on the quality properties, were studied. The degree of ripeness displays a correlation with the corresponding effective temperature totals. Here, the effect of the ripeness factor on the results was only slight, as unripe berries were removed from the samples before analysis. However, some effect may have remained, to some degree influencing the colour strength, but the organoleptic properties to a lesser degree.


2021 ◽  
Vol 919 (1) ◽  
pp. 012035
Author(s):  
N Aprilianti ◽  
R D Saraswati ◽  
S A Budhiyanti

Abstract This study aims to determine the effect of temperature and storage duration on Ulva lactuca fatty acid quality in microemulsion with ascorbic acid antioxidants. U. lactuca is a green algae obtained from coastal areas in Trenggole, Yogyakarta. The stages in this study were extraction of U. lactuca fatty acid, production of its microemulsion, and addition of ascorbic acid antioxidant. The extraction of fatty acid was carried out using hexane and ethanol solvents with a ratio of 1:19 (v/v) at 70°C for 3 hours. Furthermore, the microemulsion production was done by using three different types of surfactants, including Tween 80, Tween 20, and Span 80, at a ratio of 7,0:7,5:5,5 (v/v), respectively, with 80% water content and 200 ppm of U. lactuca fatty acid. This study consisted of three treatments of ascorbic acid antioxidants, namely 0, 100, and 200 ppm. The microemulsions with ascorbic acid were stored at 10, 30, and 50°C. The quality measurements were carried out between 4 to 20 days. The results showed the temperatures and storage time significantly affected turbidity, antioxidant activity, peroxide, and TBA value up to the 20th day of storage. The turbidity value increased more than 1% on the 20th day, while the peroxide and TBA values were still in the standard of food products. Therefore, the use of ascorbic acid as an antioxidant with a concentration of 200 ppm was appropriate to inhibit the rate of damage to the microemulsion.


2015 ◽  
Vol 7 (2) ◽  
pp. 99-109 ◽  
Author(s):  
Nadežda Prica ◽  
Milica Živkov Baloš ◽  
Sandra Jakšić ◽  
Željko Mihaljev ◽  
Brankica Kartalović ◽  
...  

The color, aroma and fl avor are major sensory characteristics of honey, which are mainly determined by the botanical origin of honey as well as by processing and storage conditions. Increased moisture content above the maximum permitted level could result in honey spoilage, which aff ects its sensory properties. The higher water-in-honey content, the greater possibility of yeast fermentation and thus the change of the fl avor and color ofhoney. Fermentation process results in alcohol formation and, in the presence of oxygen, the alcohol will break down to acetic acid and water, which causes honey to have sour taste. Thus, moisture content of honey is a critical parameter for its quality as it aff ects the stability of honey and its resistance to microbial spoilage during storage. Physicochemical analysis of moisture content and acidity of honey play an important role in determining the overall characteristic of honey and final assessment of its quality. In this study, the investigation of aforementioned parameters resulted in positive quality assessment for 48 of 50 examined honey samples produced in 2013 in the territory of Vojvodina.


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