scholarly journals The most important quality criteria of some home-grown black-currant varieties III. Aroma number, organoleptic evaluation, and degree of ripeness

1966 ◽  
Vol 38 (3) ◽  
pp. 150-161
Author(s):  
Taina Kuusi
Keyword(s):  
Quality Criteria ◽  
Organoleptic Properties ◽  
Black Currant ◽  
Organoleptic Evaluation ◽  
Quality Properties ◽  
The North ◽  
Colour Strength ◽  
Important Quality ◽  
Reducing Substances

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.

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.

scholarly journals The most important quality criteria of some home-grown black-currant varieties IV. Gas-chromatographic analysis of aroma

1966 ◽  
Vol 38 (3) ◽  
pp. 162-179
Author(s):  
Taina Kuusi ◽  
Alpo Siiriä ◽  
Terttu Kuusi
Keyword(s):  
Quality Criteria ◽  
Weather Conditions ◽  
Considerable Effect ◽  
Chromatographic Study ◽  
Black Currant ◽  
Clear Cut ◽  
Important Quality ◽  
Nitrogen Stream ◽  
Cool Summer ◽  
One Year

A gas chromatographic study has been made of the volatile aroma components of black-currant. The material consisted of 12 home-grown varieties from 6 localities taken over a period of 2 years, although the series are not complete. Separate investigation was made of the low-boiling and high-boiling parts of the aroma; in the former case, material of two years was studied, and in the latter case, that of one year only. The lower-boiling components were isolated in chilled adsorption tubes from a nitrogen stream led through a berry homogenate at room temperature. Analysis was effected at 80°C with a polyetylene glycol/teflon column (the same mass served as filling for the adsorption tubes). In all, 13 components were registered, although their occurrence, and the amounts in the different samples, were somewhat variable. As regards the different factors, the variety exercised no more than a slight effect on the aroma picture, whereas weather conditions were important, influencing the frequency of the peaks and the general aroma level; a cool summer increased the level. The northernness of the growing locality had a similar effect, although this result its of preliminary nature. The degree of ripeness and the condition had a considerable effect; the level of aromagrams was higher with more ripe samples, and in particular the ethanol content, which forms the bulk of the low-boiling aroma, was increased. A positive correlation was detected between the height of the ethanol peak and the total aroma or aroma number. By contrast, the height of the methanol peak exhibited a slight negative correlation with the degree of esterification of the pectin. The higher-boiling compounds were isolated by vacuum distillation and subsequent extraction with ether. In the gas chromatography, use was made of a butandiol succinate polyester/celite column, and the temperatures were 120 and 150°C. In all, 25 components were observed. Of the various factors, the variety showed a clear-cut influence on the aroma picture, as differences in the occurrence of the peaks and the relative heights were noted between the varieties; in this series, quantitative comparisons between the samples were impossible. The effect of locality and degree of ripeness is less well defined. Organoleptic checking showed that the changes were small in isolation of the lower-boiling components. In contrast, isolation of the higher-boiling compounds induced more changes, so that an aroma fraction obtained in the organic solvent was more terpene-like than the original aroma.

scholarly journals The most important quality criteria of some homegrown black-currant varieties I. Ascorbic acid

1965 ◽  
Vol 37 (4) ◽  
pp. 264-281
Author(s):  
Taina Kuusi
Keyword(s):  
Ascorbic Acid ◽  
Acid Content ◽  
Quality Criteria ◽  
Ascorbic Acid Content ◽  
Weather Conditions ◽  
Black Currant ◽  
Quality Properties ◽  
Clear Cut ◽  
Degree Of Maturity ◽  
North Latitude

A comparative study has been made with a view to clarification of the quality properties of some home-grown black-currant varieties. Twelve varieties were examined; samples were obtained from 6 different localities, of which the southernmost was Piikkiö, and the northernmost Rovaniemi, over a period of three years. The analytical results were compared with the totals of heat, the totals of hours of sunshine, and the precipitaition during the years concerned. Ascorbic acid, one of the most important criteria of quality, was assayed by application of the method of Robinson & Stotz, slightly modified. On the basis of the results obtained, mutual comparison of the varieties studied is possible along with consideration of the possible effects of weather conditions and the degree of north latitude of the place of growth. It is well known that the ascorbic acid content is dependent upon the variety. Accordingly, the following diminishing sequence was found in the ascorbic acid content of the varieties studied: Boskoop, Roodknop, Westwick Choice, Wellington XXX, Gerby, Wellington X, Åström, Brödtorp, Goliath, Silvergieter, Janslunda and Black of Lepaa. In this series, the amount of ascorbic acid fell from 250 to 127 mg/100g; considerable variations occurred in each variety. As for weather conditions, the summer temperature showed the greatest effect; in general, low temperature increased the amount of ascorbic acid. However, Brödtorp and Black of Lepaa often formed an exception. The number of hours of sunshine produced a similar effect, but to a lesser degree; by contrast, precipitation evinced no clear-cut effect. The degree of north latitude of the locality also seems to exert some effect, probably mainly because a latitude further north means a lowering of the temperature, and consequent retardation of the ripening, which again causes higher ascorbic acid values. Comparison with published reports shows that in principle the present results are in line with those presented earlier. The differences might be attributable to different methods of assay, or variability in the varieties concerned. The northern latitude of the place of growth and the degree of maturity may be of importance.

scholarly journals The most important quality criteria of some homegrown black-currant varieties II. Dry matter, pectin, acid content, colour and formol value

1965 ◽  
Vol 37 (4) ◽  
pp. 282-304
Author(s):  
Taina Kuusi
Keyword(s):  
Acid Content ◽  
Dry Matter ◽  
Summer Temperature ◽  
Weather Factors ◽  
Black Currant ◽  
Degree Of Esterification ◽  
Quality Properties ◽  
Berry Size ◽  
Colour Strength ◽  
High Summer Temperature

The quality properties of black-currant have been investigated in respect of 12 home-grown varieties. Samples were obtained from 6 localities over a period of 3 years. The properties studied were dry matter, pectin and its degree of esterification, acid content, colour strength, and formol value. As regards dry matter, the differences between the varieties were small. A high summer temperature diminished the dry matter values. Some variations existed between the varieties in respect of pectin. Thus Wellington XXX and X contained an abundant amount of pectin, whereas Brödtorp and Black of Lepaa contained little. A high summer temperature lowered the pectin content, but the degree of its esterification remained high. A corresponding effect was noted as a consequence of the degree of north latitude of the place of growth: the amount of pectin was increased and its degree of esterification was lowered towards the north. With respect to the acid content, differences were remarked among the varieties, corresponding approximately to results reported earlier in literature. As a rule, the acid content of the home-grown varieties is higher than the values so reported. Of weather factors, sunshine seems to exercise most influence on the acid content, the acid being increased by a lack of it. Similarly, differences among the varieties were found in colour strength. This property seems to bear a negative correlation to the berry size, since the colouring compounds are localized in the skin part of the berry. The colour strength depends markedly upon the summer temperature, as is evidenced by both the comparison of the different years, and that of the different localities. Slight differences in the formed value were noted between the varieties. However, this value depends substantially upon the degree of maturity; it falls during ripening, a fact which renders comparison difficult.

Molecular Characterization of Novel Porcine Circovirus 3 (PCV3) in Pig Populations in the North of Vietnam

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Nguyen Van Giap ◽  
Chung Hee Chun ◽  
Huynh Thi My Le ◽  
Cao Thi Bich Phuong ◽  
Vu Thi Ngoc ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Porcine Circovirus ◽  
The North ◽  
Porcine Circovirus 3

scholarly journals Size-resolved characterization of organic aerosol in the North China Plain: new insights from high resolution spectral analysis

2021 ◽  
Author(s):  
Weiqi Xu ◽  
Chun Chen ◽  
Yanmei Qiu ◽  
Conghui Xie ◽  
Yunle Chen ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
North China Plain ◽  
North China ◽  
Fine Particles ◽  
Large Fraction ◽  
Organic Aerosol ◽  
Size Distributions ◽  
The North ◽  
The Impact

Organic aerosol (OA), a large fraction of fine particles, has a large impact on climate radiative forcing and human health, and the impact depends strongly on size distributions. Here we...

scholarly journals Electrical characterization of the North Anatolian Fault Zone underneath the Marmara Sea, Turkey by ocean bottom magnetotellurics

2013 ◽  
Vol 193 (2) ◽  
pp. 664-677 ◽  
Author(s):  
T. Kaya ◽  
T. Kasaya ◽  
S. B. Tank ◽  
Y. Ogawa ◽  
M. K. Tuncer ◽  
...  
Keyword(s):  
Fault Zone ◽  
Electrical Characterization ◽  
North Anatolian Fault ◽  
Marmara Sea ◽  
Ocean Bottom ◽  
North Anatolian Fault Zone ◽  
The North
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