scholarly journals Changes of quality of rennets during storing

2012 ◽  
Vol 60 (6) ◽  
pp. 189-196
Author(s):  
Monika Kozelková ◽  
Miroslav Jůzl ◽  
Táňa Lužová ◽  
Květoslava Šustová ◽  
Aneta Bubeníčková
Keyword(s):  
Near Infrared ◽  
Color Change ◽  
Coagulation Time ◽  
Time Activity ◽  
Spectrophotometric Methods ◽  
Color Changes ◽  
Rennet Coagulation ◽  
Total Color Change ◽  
Instrumental Methods

This work deals about evaluation of qualitative parameters of rennets. During the six months storing of rennets were determined following qualitative parameters: pH, rennet coagulation time, activity (strange) of rennet and dose of rennet, and finally were used instrumental methods: Near infrared spectroscopy (NIR) for recognizing age of rennets and spectrophotometric methods of determining the color of rennets. The theory found in the references suggests, that the activity of rennet should decrease by an average of 1–2 % per month, but the results are showing, that are changing quality of rennets namely mostly activity (strange) of rennet, which was decreased by 33% per half year. In analysis of color of rennets weren’t observed major changes by the whole group. Some statistical differences were detected in the partial values L*a*b*, most advantageous were evaluation by rennet total color change during storage, which were higher than noticeable change in four samples. The least color changes (P > 0.05) were observed in microbial rennets, with no values observed (ΔEab < 2) that can be recognized even by the human eye when subjected to parallel comparison. It was found that the NIR analysis can be used to recognizing of rennets, which are different ages.

scholarly journals PENGARUH RESIN TERHADAP PERUBAHAN WARNA PADA CAT TEMBOK

2019 ◽  
Vol 5 (2) ◽  
pp. 132
Author(s):  
Nurlela Nurlela ◽  
Risnawati Risnawati
Keyword(s):  
Film Thickness ◽  
Vinyl Acetate ◽  
Polyvinyl Acetate ◽  
Color Change ◽  
Color Difference ◽  
Background Color ◽  
Color Changes ◽  
Synthetic Resins ◽  
Color Background

The Influence of Resin against the Change of Color on the Wall PaintThe quality of the paint is determined by the resin used. Synthetic resins for polymer paints are made by combining several monomers to achieve various characteristics. The incorporation of some monomers such as polyvinyl acetate resin, acrylic vinyl resin and acrylic styrene resin which act as a binder can affect the quality of the paint especially the color change. The purpose of this study is to find the color changes that occur on the wall paint by using Poly Styrene Acrylic , Poly Vinyl Acetate and Poly Vinyl Acrylic. From the results of the measurement of color difference, significant color change occurs in the Poly Vinyl Acetate (PVAc) + Poly Vinyl Acrylic (PVA) and Poly Styrene Acrylic (PSA). The results of the quality test of the three resins based on pH test, scrub test and viscosity test, PSA has better quality compared to PVA + PVAc and PVA resin. From the color difference measurement test, some things need to be considered, are temperature, film thickness, substrate color/background color and measurement conditions (measured in wet sample/in plate/dry surface) and test on resin added additive according to the type of each resin.Keywords: Paint, Resin, Color Changes, Poly Vinyl Acetate, Poly Styrene.ABSTRAK Kualitas dari cat sangat ditentukan oleh resin yang digunakan. Resin sintetis untuk cat berupa polimer yang dibuat dengan menggabung beberapa monomer untuk mencapai berbagai karakteristik. Penggabungan dari beberapa monomer seperti resin poli vinil asetat, resin vinil akrilik dan resin stirena akrilik yang berfungsi sebagai pengikat mampu mempengaruhi kualitas cat terutama dari perubahan warna. Tujuan dari penelitian ini adalah untuk mengetahui perubahan warna yang terjadi pada cat tembok dengan menggunakan Poli Stirena Akrilik, Poli Vinil asetat dan Poli Vinil Akrilik. Dari hasil pengukuran perbedaan warna, perubahan warna cukup signifikan terjadi pada resin Poli vinil Asetat (PVAc) + Poli Vinil Akrilik (PVA) dan resin  Poli Stirena Akrilik (PSA). Hasil uji Kualitas cat dari ketiga resin berdasarkan uji pH, uji scrub dan uji viscositas, PSA memiliki kualitas yang lebih baik dibandingkan dengan resin PVA+PVAc dan PVA. Dari pengujian pengukuran perbedaan warna, beberapa hal yang perlu di perhatikan, yaitu suhu, film thickness, warna substrat/background color dan kondisi pengukuran (diukur dalam keadaan wet sample/dalam bentuk plate/dry surface) dan pengujian terhadap resin yang ditambahkan zat aditif yang sesuai dengan tipe masing-masing resin tersebut.Kata Kunci: Cat, Resin, Perubahan Warna, Poli Vinil, Poli Stirena.

scholarly journals Methods of Assessing Milk Proteins Coagulation as a Part of the Forecasting System of Technological Properties

2021 ◽  
pp. 503-519
Author(s):  
Elena Illarionova ◽  
Alexandr Kruchinin ◽  
Svetlana Turovskaya ◽  
Alana Bigaeva
Keyword(s):  
Near Infrared ◽  
Milk Proteins ◽  
Raw Milk ◽  
Optical Measurements ◽  
Integrated Monitoring ◽  
Milk Clotting ◽  
Advantages And Disadvantages ◽  
Rennet Coagulation ◽  
Instrumental Methods ◽  
Instrumental Approaches

Introduction. An integrated monitoring of raw milk’s contents, quality, and security is a key factor that guarantees the high-quality dairy production. As a result, new research methods of rennet clotting are a topical and urgent area of study. The research objective was to systemize and analyze the basic criteria and assessment methods of rennet-induced protein gels in milk systems. Study objects and methods. The authors reviewed the official Russian criteria and methods of raw milk assessment by its rennet coagulation properties. The research also featured the most widespread instrumental approaches used in best practices from around the world. Results and discussion. In Russian and foreign cheese production, milk is always tested for its physicochemical and microbiological indicators, with a mandatory check of its coagulation characteristics. Russian cheese-makers use different modifications of rennet and rennet-fermenting tests based on subjective sensory evaluation, while international scientific trends in this area aim at developing and improving instrumental methods by using a complex indicator MCP. This indicator characterizes the parameters of rennet coagulation with the help of such devices as Formagraph, Lattodinamografo, Optigraph, etc. Formagraph is a simple instrument for measuring rheological properties of milk clotting. It was popular in the late XX century. The resent years saw the development of other methods of instrumental control, including those based on optical measurements. For instance, Ortigraph is one such instrument that receives unified data on coagulation properties of raw milk by using near-infrared waves. Sensory and instrumental methods have their advantages and disadvantages. However, the most significant criteria for a quick test of cheeseability, yield, and quality are the speed of analysis and the comparability and reproducibility of results. Conclusion. To improve cheeseability testing, Russian cheese-makers need to use the international experience, which offers standardized evaluation criteria in combination with various instrumental approaches. However, the integration of foreign regulations and methods into Russian studies is not the only option. The improvement and development of national instrumental methods of evaluating milk protein coagulation is also crucial.

scholarly journals Assessment of changes in color and color parameters of light-cured composite resin after alternative polymerization methods

2013 ◽  
Vol 07 (01) ◽  
pp. 110-116 ◽  
Author(s):  
Emine Sirin Karaarslan ◽  
Bulbul Mehmet ◽  
Ertas Ertan ◽  
Mehmet Ata Cebe ◽  
Aslihan Usumez
Keyword(s):  
Composite Resin ◽  
Color Change ◽  
Color Difference ◽  
Study Groups ◽  
Color Parameters ◽  
Color Changes ◽  
Yellow Color ◽  
Before And After ◽  
Total Color Change

ABSTRACTObjective:To examine the amount of change in color and color parameters of a composite resin (Filtek P60) polymerized by five different polymerization methods.Methods: A Teflon mold (6mm in diameter, 2mm in height) was used to prepare the composite resin discs (n=10). G1: Polymerization with inlay oven; G2: Polymerization with HQTH and autoclave; G3: Polymerization with LED and autoclave; G4: Polymerization with HQTH; G5: Polymerization with LED. Colorimetric values of the specimens before and after polymerization were measured using a spectrophotometer. The CIE L*a*b color system was used for the determination of color difference. Analysis of variance (ANOVA) was used to analyze the data for significant differences. Tukey’s HSD test and paired two-tailed tests were used to perform multiple comparisons (α=.05).Results: There were no significant differences in total color change (ΔE*ab) among the polymerization groups (P>.05). However, the lowest color change (ΔE*ab) value was 3.3 in LED and autoclave; the highest color change (ΔE*ab) value was 4.6 in HQTH. For all groups, CIE L*, C*ab and a*values decreased after polymerization (P<.05). The highest Δb* and ΔC*ab values were observed in specimens polymerized in an inlay oven (P<.05).Conclusion: Composite resin material showed color changes above the clinically accepted value in all study groups (ΔE*ab≥3.3). All specimens became darker during investigation (ΔL*< 0). Specimens polymerized with inlay oven presented the highest Δb* values which means less yellow color in specimens. (Eur J Dent 2013;7:110-116)

scholarly journals Color stability of esthetic coatings applied to nickel-titanium archwires

2017 ◽  
Vol 46 (5) ◽  
pp. 307-311
Author(s):  
Marcus Vinicius Neiva Nunes do REGO ◽  
Geórgia Wain Thi LAU ◽  
Yago Carneiro ARAÚJO ◽  
Rayssa Melo e SILVA
Keyword(s):  
Epoxy Resin ◽  
Color Change ◽  
Color Stability ◽  
Surface Characteristics ◽  
Nickel Titanium ◽  
Staining Solution ◽  
Color Changes ◽  
Significant Difference ◽  
Total Color Change ◽  
Coating Type

Abstract Introduction Color stability is an important feature to be considered when using esthetic coated archwires. Objective To evaluate color changes on the surface of esthetic nickel-titanium archwires coated with Teflon (Ortho Organizers, USA) or epoxy resin (Tecnident, Brazil) after immersion in staining solution. Material and method Twelve 20-mm-long wire segments were used for each type of coating, which were mounted as two test specimens with a width of 7 mm each. The buccal surface of the archwires was evaluated for fluorescence and color measurements both at baseline and after immersion in a staining solution for 21 days using the VITA Easyshade® Compact spectrophotometer (Model DEASYC220). Differences in total color change according to coating type were compared using an independent samples t-test (p<0.05). The surface characteristics of as-received coated archwires were assessed using scanning electron microscopy. Result Color changes were observed on the esthetic coatings, with a significant difference between the two brands analyzed. Surface analysis revealed flaws such as wear, pitting, elevations, lack of material, granulation, grooves, cracks, and lack of standardization in the coating process in all as-received archwires, but flaws were less evident in epoxy-resin coatings. Conclusion The two esthetic coatings did not show color stability, but Teflon coatings showed a more intense color change than epoxy-resin coatings.

scholarly journals Responses of Apples to Postharvest Jasmonate Treatments

1998 ◽  
Vol 123 (3) ◽  
pp. 421-425 ◽  
Author(s):  
Xuetong Fan ◽  
James P. Mattheis ◽  
John K. Fellman
Keyword(s):  
Color Change ◽  
Titratable Acidity ◽  
Apple Fruit ◽  
Soluble Solids ◽  
Maximum Effect ◽  
Minimum Concentration ◽  
Color Changes ◽  
Promotive Effect ◽  
Solids Content

The effect of exogenous methyl jasmonate (MJ) and jasmonic acid (JA) compared with the effect of ethephon on surface color and quality of `Golden Delicious' and `Fuji' apples (Malus ×domestica Borkh.) was studied. Treatments were applied by dipping fruit in water solutions of JA, MJ, or ethephon or by exposing fruit to MJ vapors. Response to MJ vapor treatment depended on fruit developmental stage, with the maximum effect occurring as fruit began to produce ethylene. MJ promoted color changes more effectively than JA. The promotive effect of JA increased with JA concentration. A minimum concentration of 0.1 mmol·L-1 JA was needed to promote significant color change within 15 d at 20 °C. JA at 1 or 10 mmol·L-1 promoted color change more effectively than 0.35 or 3.5 mmol·L-1 ethephon. The magnitude of JA-promoted responses decreased at lower temperatures. Treatments with 10 mmol·L-1 JA or 3.5 mmol·L-1 ethephon were phytotoxic. Treatments using JA at 1 or 10 mmol·L-1 in water promoted loss of fruit titratable acidity compared to controls. Firmness and soluble solids content were relatively unresponsive to JA treatments. Based on these results, using JA and MJ to promote degreening of apple fruit with minimal loss of other quality attributes appears feasible.

scholarly journals Effects of Chlorella sp. Additions on the Changes of Visceral Mass and Proximate Contents of Shellfish

2019 ◽  
Vol 7 (2) ◽  
pp. 79
Author(s):  
Clara Dhisa Sumunaring Ratna ◽  
Trijoko Trijoko
Keyword(s):  
Color Change ◽  
Food Preferences ◽  
Nutrient Content ◽  
Northern Coast ◽  
Visceral Mass ◽  
Color Changes ◽  
Chlorella Sp ◽  
Good Taste ◽  
High Nutrient

Shellfish, called as kerang in Indonesia, contains animal protein that’s popular, making it as and important fisheries and marine commodity. Supported by the good taste and high nutrient content in it. Paphia undulata or Kerang  Batik, Peryglipta reticulata or Kerang Kemiri, Meretrix meretrix or Kerang Tahu, and Codakia tigerina or Kerang Madu, are consumption shells from northern coast of Java. To improve the quality of shellfish, Chlorella added as shellfish food preferences. It supported by the high nutrient content in Chlorella sp. Shellfish kept for 15 days in a basket with a sand substrate and drainage from sea. Therefore, the water quality had been controlled for the changed of salinity and water temperature. Parameters used to see the improvement shellfish quality is the color changes on visceral mass and the changes of proximate content (moisture, protein, fat, carbohydrate and ash). This study proves the color changes on visceral mass and proximate content. The color change occurs on the visceral mass and the gills. The changes of viscerall mass occurs on kerang batik from white greyish to yellow while the more clearly gills occurs on kerang madu and kemiri. Meanwhile, the change of proximate shown by the increasing of protein and moisture on all the spesies while on the otherside the decreasing of carbohydrate and ash, but the increasing of fat only occurs on kerang batik and kerang madu. The higher proximate changes occur on kerang madu, where the ammount of moisture at 71,43 ± 0,03 %, the protein at 16,55 ± 0,02 %, the fat at 1,35 ± 0,04 %, the carbohydrate at 2,9 ± 0,03 %, and the ash at 8,09 ± 0,04 %. The conclusion of this research are kerang madu has the higher positive influences by addition of Chlorella, shown by the increasing of proximate contents and the clearly of gills. Keywords : addision of Chlorella sp., changes of visceral mass, proximate, shellfish

Expanded Thermochromic Color Changes in VO2 Thin Film Devices Using Structured Plasmonic Metal Layers

2013 ◽  
Vol 1494 ◽  
pp. 171-177
Author(s):  
Yan Wang ◽  
John F. Muth
Keyword(s):  
Thin Films ◽  
Near Infrared ◽  
Color Change ◽  
Large Change ◽  
Metallic Phase ◽  
Metallic Thin Films ◽  
Color Changes ◽  
Surface Plasmas ◽  
Metal Layers

ABSTRACTWe investigate metallic thin films on VO2 and show that the magnitude of the reflected color change in that visible portion of the spectrum as VO2 undergoes the insulating to metallic phase transition can be controlled by changing the type of metal, the thickness of the metal and by patterning the metal at the nano scale. We consider the role of surface plasmas in the metal film and show that in the near infrared, the magnitude of the reflectivity increase for metal coated VO2 films, but decrease for uncoated VO2 thin films. This is explained in the context of Fresnel equations and considering the large change in the imaginary part of the dielectric constant as the VO2 changes state from the insulating to metallic phase.

Assessment of spoilage potential posed by Alicyclobacillus spp. in plant-based dairy beverages mixed with fruit juices during storage

2020 ◽  
Author(s):  
ANASTASIA KAPETANAKOU ◽  
Konstantina Passiou ◽  
Kalliopi Chalkou ◽  
Panos Skandamis
Keyword(s):  
Color Change ◽  
Inoculum Size ◽  
Fruit Juices ◽  
Mitigation Strategies ◽  
Initial Inoculum ◽  
Color Changes ◽  
Beverage Industry ◽  
Total Color Change ◽  
And Storage ◽  
Dairy Beverages

The scope of the present study was to assess the spoilage potential of different Alicyclobacillus spp. in commercial pasteurized (ambient-stable) plant-based dairy beverages mixed with fruit juices at different inoculation levels and storage temperatures. Different products (Coconut and Berry‒CB; Almond, Mango, and Passionfruit‒AMP; Oat, Strawberry, and Banana‒OSB) were inoculated with 10 or 2x103 spores/mL of either Alicyclobacillus acidoterrestris or A. fastidiosus or A. acidocaldarius strain composites, while non‒inoculated samples served as controls. Samples inoculated with A. acidoterrestris and A. fastidiosus were stored at 30°C and 45°C, while in case of A. acidocaldarius storage took place at 50°C for 240 days. Gas composition, Alicyclobacillus spp. populations, total viable counts, pH, aw, color, and guaiacol off-taste were monitored. CB and AMP supported growth of A. acidoterrestris and A. fastidiosus, reaching populations of 4.0‒5.0 log CFU/mL. In OSB, populations of the latter species remained close to the initial inoculation levels during storage at 30°C, while at 45°C, the populations declined &lt;1 CFU/mL. A. acidocaldarius growth was supported only in CB samples, reaching ca. 3.0 log CFU/mL at 50°C, regardless of initial inoculum size. Total color change was increased during storage, however the instrumentally recorded color changes were not macroscopically visible. Spoilage in terms of guaiacol off-taste, was identified only in CB and AMP samples inoculated with A. acidoterrestris after 60 days at 30°C and 45°C. Considering that these products are becoming increasingly popular and the scarcity of existing literature related to their spoilage by Alicyclobacillus spp., the contribution of the findings and data of present study are critical for assessing the significance of Alicyclobacillus spp. as a potential spoilage hazard in these products and thus, to assist in the design and implementation of effective mitigation strategies by the beverage industry.

Effect of frequency of milking on yield, composition and processing quality of milk

2002 ◽  
Vol 69 (3) ◽  
pp. 367-374 ◽  
Author(s):  
BERNADETTE O'BRIEN ◽  
GERARD RYAN ◽  
WILLIAM J. MEANEY ◽  
DAVID McDONAGH ◽  
ALAN KELLY
Keyword(s):  
Milk Yield ◽  
Milk Fat ◽  
Milk Composition ◽  
Plasmin Activity ◽  
Coagulation Time ◽  
Once Daily ◽  
Rennet Coagulation ◽  
Milking Frequency ◽  
Quality Of Milk

The objective was to determine the effect of once-daily milking (ODM) and omitting one evening milking each week (13TWM), in late lactation on milk production, composition and processability. Seventy-two cows were assigned to three treatments (ODM, 13TWM and twice-daily milking [TDM]) from 4 October to 12 December. Cows were on average 218 d into lactation at the start of the trial, and all cows were managed similarly throughout the trial. Milk yields and gross milk composition of cows on all treatments were measured, and milk samples for detailed compositional and processability analysis were collected from TDM and ODM treatments at two consecutive milkings and at one milking each week, respectively. Milk yield was significantly reduced (P<0.001) and milk fat and protein concentrations were increased (P<0·01) with ODM compared with TDM. Milk yield and fat and protein concentrations of milk from TDM and 13TWM herds were similar. Casein concentrations in ODM and TDM milks were similar, but ODM milk had a higher (P<0·05) whey protein content. Somatic cell count of ODM and TDM milks was similar. Rennet coagulation time (RCT) and curd firmness (A60) of milk were not affected by milking frequency. However, rate of curd aggregation (K20) of ODM milk was reduced (P<0·05) compared with that of TDM milk. Plasmin activity in ODM milk was numerically higher than in TDM milk, but the effect was not significant. ODM milk had higher NAGase activity than TDM milk (P<0·01). In conclusion, once daily milking reduced milk yield by 29% and did not adversely affect the processability of milk. Moreover, one evening milking per week could be eliminated without adverse effects on milk yield or composition.

scholarly journals The Effects of Natural Weathering on Color Stability of Impregnated and Varnished Wood Materials

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Turkay Turkoglu ◽  
Ergun Baysal ◽  
Hilmi Toker
Keyword(s):  
Scots Pine ◽  
Color Change ◽  
Color Stability ◽  
The Other ◽  
Natural Weathering ◽  
Color Changes ◽  
Oriental Beech ◽  
Total Color Change ◽  
Dark Color ◽  
Copper Arsenate

The aim of this study was to investigate effects of natural weathering on color stability of Scots pine (Pinus sylvestrisL.) and Oriental beech (Fagus orientalisL.) impregnated with some chemicals [tanalith-E (TN-E), adolit-KD5 (AD-KD5), and chromated copper arsenate (CCA)] and then varnished [synthetic varnish (SV) and polyurethane varnish (PV)]. While applying varnish increased lightness, impregnation decreased lightness of the wood specimens before natural weathering. Natural weathering caused greenish, bluish, and dark color tones of the wood surface. Total color change was increased with increasing exposure times in natural weathering. Untreated (control) wood specimens exhibited higher color changes than the other wood specimens in all the stages of natural weathering. The total color changes of untreated Oriental beech specimens were less than untreated Scots pine specimens. The color stability of impregnated and varnished wood specimens gave better results than untreated and solely varnished wood specimens after natural weathering. The best color stability was obtained from both Oriental beech and Scots pine wood impregnated with TN-E before PV coating.

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