scholarly journals Using Dielectric Relaxation Spectroscopy to Characterize the Glass Transition and Onset of Crystallinity of Skim-Milk Powder

2018 ◽  
Author(s):  
Martin G. Buehler
Keyword(s):  
Glass Transition ◽  
Shelf Life ◽  
Dielectric Relaxation ◽  
Loss Tangent ◽  
Milk Powder ◽  
Skim Milk ◽  
Skim Milk Powder ◽  
Dielectric Relaxation Spectroscopy ◽  
Scanning Calorimetry ◽  
Boundary Curves

This paper describes the dielectric relaxation spectroscopy (DRS) method for obtaining glass transition temperature and the onset of crystallinity of skim milk powder (SMP). The methodology consists of exposing SMP samples to numerous constant temperatures, T, and water activities, aw, and measuring the relaxation time. Measurements are based on changes in the loss-tangent height at its peak frequency. Glass transition times are identified at peaks in the loss-tangent height versus time curve and the onset of crystallinity times are identified when the loss-tangent height collapses. The analysis leads to two boundary curves: glass transition Tg, aw curve and the onset of crystallinity Tc, aw curve. They separate the SMP stable (long shelf life) and unstable (short shelf life) regions. Two curve fitting algorithms were developed for (a) aw2, tg curve where tg is the time to glass transition and aw2, tc curve where time tc is the time to onset of crystallinity and (b) Tg, aw and Tc, aw boundary curves. Finally, the DRS data are compared to differential scanning calorimetry (DSC) results.

Studies on sensory and keeping qualities of pumpkin based Kheer

2015 ◽  
Vol 34 (4) ◽  
Author(s):  
Shaikh Adil ◽  
Sudhakar Changade ◽  
Anant Dhotre ◽  
Santosh Chopde
Keyword(s):  
Shelf Life ◽  
Milk Powder ◽  
Skim Milk ◽  
Storage Period ◽  
Skim Milk Powder ◽  
Overall Acceptability ◽  
Significant Difference ◽  
The Difference ◽  
Shelf Life Studies ◽  
Pumpkin Powder

The objective of this study was evaluation of the shelf life of reconstituted <italic>kheer</italic> packed in previously sterilized cups and stored at 10± 1°C for 3 days. During period of studies the samples were examined for sensory evaluation after the first, second and third day using five treatments T1 (Pumpkin flesh <italic>kheer</italic>), T2 (1 per cent pumpkin powder + 43 per cent skim milk powder), T3 (2 per cent pumpkin powder + 42 per cent skim milk powder), T4 (3 per cent pumpkin powder + 41 per cent skim milk powder) and T5 (4 per cent pumpkin powder + 40 per cent skim milk powder). Samples were studied for sensory properties <italic>viz</italic>. colour, flavour, body texture, appearance and overall acceptability. Statistical analysis for shelf life studies revealed that both the treatments and storage period had significant effect on sensory qualities of the product. The scores for colour, flavour, body and texture, appearance and overall acceptability of all <italic>kheer</italic> samples decreased with the advancement of storage period. The rate of decline in the flavour score of T3 was more as compared to all other treatments. The score for T3 was (7.12) on first day which dropped to (6.05) on third day. The rate of decrease of scores for body and texture was more in treatment T5 than T1, T2, T3 and T4. There was a statistically significant difference in the appearance of reconstituted <italic>kheer</italic> samples for all the treatments on the day of preparation. The difference between all treatments was non-significant on second and third day of storage. The overall acceptability for T1, T2, T3, T4 and T5 samples decreased with the progress of storage period.

Infant food based on coconut protein, groundnut protein isolate and skim milk powder. I.—Preparation, chemical composition and shelf-life

1964 ◽  
Vol 15 (12) ◽  
pp. 839-841 ◽  
Author(s):  
M. R. Chandrasekhara ◽  
G. Ramanatham ◽  
G. Rama Rao ◽  
D. S. Bhatia ◽  
M. Swaminathan ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Shelf Life ◽  
Milk Powder ◽  
Skim Milk ◽  
Skim Milk Powder ◽  
Protein Isolate ◽  
Infant Food ◽  
Coconut Protein

Water sorption and glass transition properties of spray dried lactose hydrolysed skim milk powder

LWT ◽  
2007 ◽  
Vol 40 (9) ◽  
pp. 1593-1600 ◽  
Author(s):  
Ashok K. Shrestha ◽  
Tony Howes ◽  
Benu P. Adhikari ◽  
Bhesh R. Bhandari
Keyword(s):  
Glass Transition ◽  
Water Sorption ◽  
Milk Powder ◽  
Skim Milk ◽  
Skim Milk Powder ◽  
Spray Dried

scholarly journals PEG-POSS Star Molecules Blended in Polyurethane with Flexible Hard Segments: Morphology and Dynamics

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 99
Author(s):  
Konstantinos N. Raftopoulos ◽  
Edyta Hebda ◽  
Anna Grzybowska ◽  
Panagiotis A. Klonos ◽  
Apostolos Kyritsis ◽  
...  
Keyword(s):  
Glass Transition ◽  
Star Polymer ◽  
Polymerization Process ◽  
Degree Of Crystallinity ◽  
Dielectric Relaxation Spectroscopy ◽  
Scanning Calorimetry ◽  
Similar System ◽  
Soft Phase ◽  
Hard Segments ◽  
Star Molecules

A star polymer with a polyhedral oligomeric silsesquioxanne (POSS) core and poly(ethylene glycol) (PEG) vertex groups is incorporated in a polyurethane with flexible hard segments in-situ during the polymerization process. The blends are studied in terms of morphology, molecular dynamics, and charge mobility. The methods utilized for this purpose are scanning electron and atomic force microscopies (SEM, AFM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and to a larger extent dielectric relaxation spectroscopy (DRS). It is found that POSS reduces the degree of crystallinity of the hard segments. Contrary to what was observed in a similar system with POSS pendent along the main chain, soft phase calorimetric glass transition temperature drops as a result of plasticization, and homogenization of the soft phase by the star molecules. The dynamic glass transition though, remains practically unaffected, and a hypothesis is formed to resolve the discrepancy, based on the assumption of different thermal and dielectric responses of slow and fast modes of the system. A relaxation α′, slower than the bulky segmental α and common in polyurethanes, appears here too. A detailed analysis of dielectric spectra provides some evidence that this relaxation has cooperative character. An additional relaxation g, which is not commonly observed, accompanies the Maxwell Wagner Sillars interfacial polarization process, and has dynamics similar to it. POSS is found to introduce conductivity and possibly alter its mechanism. The study points out that different architectures of incorporation of POSS in polyurethane affect its physical properties by different mechanisms.

Improved heat stability of recombined evaporated milk emulsions by wet heat pretreatment of skim milk powder dispersions

2021 ◽  
pp. 106757
Author(s):  
Jianfeng Wu ◽  
Simin Chen ◽  
Teng Wang ◽  
Hao Li ◽  
Ali Sedaghat Doost ◽  
...  
Keyword(s):  
Milk Powder ◽  
Skim Milk ◽  
Heat Stability ◽  
Skim Milk Powder ◽  
Heat Pretreatment ◽  
Wet Heat

Anti-obesity effects of Lactobacillus rhamnosus 4B15, and its synergy with hydrolysed lactose skim milk powder

2021 ◽  
pp. 104997
Author(s):  
Sejeong Kim ◽  
Jae Yeon Joung ◽  
Daekyoung Kang ◽  
Nam Su Oh ◽  
Yohan Yoon
Keyword(s):  
Milk Powder ◽  
Lactobacillus Rhamnosus ◽  
Skim Milk ◽  
Skim Milk Powder

A note on the performance and management of calves reared on cold acidified milk replacer fed ad libitum

1983 ◽  
Vol 36 (1) ◽  
pp. 147-150 ◽  
Author(s):  
W. S. Thickett ◽  
N. H. Cuthbert ◽  
T. D. A. Brigstocke ◽  
M. A. Lindeman ◽  
P. N. Wilson
Keyword(s):  
Milk Powder ◽  
Skim Milk ◽  
Live Weight ◽  
Skim Milk Powder ◽  
Barley Straw ◽  
Milk Replacer ◽  
Bull Calves ◽  
The Mean ◽  
Ad Libitum ◽  
Dry Food

ABSTRACTResults are presented from six trials dealing with aspects of management on the cold ad libitum system of calf rearing using an acidified milk replacer containing over 600 g skim milk powder per kg.Thirty-six calves were housed in pens of six for each trial and were fed through a teat and pipeline from a storage barrel. Acidified milk replacer, pH 5·6, was mixed cold at 125 g/1 and made available ad libitum to 3 weeks. A rationed allowance was given daily, on a reducing scale, over the following 2 weeks with weaning completed at 35 days. A pelleted dry food containing 180 g crude protein per kg, together with water in buckets and barley straw in racks, was available ad libitum throughout. Each trial lasted 8 weeks. Results for the mean of the six cold ad libitum trials involving 216 calves were compared with the mean results of 10 conventional bucket-fed trials carried out separately at the same unit, involving 912 calves. All calves were purchased British Friesian male (bull) calves.Calves on the ad libitum system showed improved live-weight gains of 9·4 kg at 3 weeks, 8·8 kg at 5 weeks and 7·5 kg at 8 weeks, compared with the conventional system. The consumption of milk replacer powder was higher in ad libitum trials at 29·4 kg cf. 12·5 kg by bucket but intake of pelleted dry feed was lower on the ad libitum system at 50·7 kg cf. 71·3 kg to 8 weeks. Calf appearance scores were significantly improved on the ad libitum system which gave the main improvement in performance in the first 3 weeks.

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