scholarly journals Wall deposition experiments in a new spray dryer

Author(s):  
Timothy A. G. Langrish ◽  
Xing Huang ◽  
Chao Zhong

Wall deposition tests have been conducted on a new spray-drying sytem. Solutions of salt and skim milk powder have been dried with different inlet temperatures (170 °C and 230 °C) and solid contents (8.8 wt% and 30 wt%). The experiment showed that increasing the temperature caused an decrease in the amount of deposition for salt solution, but an increase for skim milk. The experiments also showed that a higher solid content caused an increase in deposition. The trends agreed with the studies using a conventional spray dryer, but the amount of deposition appeared to be lower in the new spray dryer at the same operating conditions Keywords: Spray drying; wall deposition

2021 ◽  
Author(s):  
K. Cevik ◽  
H. Yalcin

Abstract The aim of this study was to investigate microencapsulation of palm oil fractions (palm olein (POL) and 90% palm olein+10% palm stearin (POS)) using skim milk powder (SMP) and maltodextrin (MD) by spray drying. Twenty-seven emulsions with POL were prepared to determine appropriate solid content (SC) and oil/coating material ratio (O/CM) of the emulsions to be fed into the spray dryer. Emulsion properties, such as viscosity and stability, were affected by SC and coating materials. The effects of coating materials used in microencapsulation of POL and POS were also tested by using different ratios of SMP and MD. The microencapsulation efficiency (69.28–84.97%), the microencapsulation yield (14.50–31.79%), and the peroxide value (4.12–7.07 meq O2/kg oil) of the powders were affected by the coating materials (P < 0.05).


1955 ◽  
Vol 53 (4) ◽  
pp. 387-397 ◽  
Author(s):  
P. H. R. Anderson ◽  
Doris M. Stone

SummaryEight explosive outbreaks of food poisoning, occurring in school canteens in England during 1953 and affecting 1190 known cases, are described. The clinical features were characteristic of the toxin type of illness. No deaths occurred.The food causing all of these outbreaks was prepared from spray-dried skim milk powder. It was not subsequently heat-treated and was usually consumed 3–4 hr. after preparation.The spray-dried milk powder proved to contain a high content of bacteria, including large numbers of Staph. aureus, of a phage pattern often associated with food poisoning. The assumption was therefore made that these outbreaks were caused by staphylococcal enterotoxin.Because the food was often consumed within 3–4 hr. of reconstitution of the milk powder—before, in fact, the staphylococci had had time to grow—it is concluded that the poisoning must have been due mainly to pre-formed toxin.Consideration is given to the opportunities for the formation of toxin in a spray-drying plant, and reasons are brought forward for believing that it is formed mainly in the balance tank where the warm milk is kept, sometimes for several hours, before passing into the final drying chamber.The processing of the milk and the precautions for preventing contamination of the finished product are discussed.


2006 ◽  
Vol 69 (3) ◽  
pp. 682-685 ◽  
Author(s):  
ORGUN DEVECİ ◽  
EMEL SEZGİN

In this study, skim milk powder was produced from cow's milk contaminated artificially with aflatoxin M1 (AFM1) at two different levels, 1.5 and 3.5 μg/liter (ppb), and the effects of process stages on the AFM1 contents were investigated. Pasteurization, concentration, and spray drying caused losses of about 16, 40, and 68%, respectively, in AFM1 content of the milk contaminated with 1.5 μg/liter AFM1, and losses of 12, 35, and 59%, respectively, in the milk contaminated with 3.5 μg/liter AFM1. These losses were found to be statisticially significant at the level of P &lt; 0.01. After 3- and 6-month storage periods, AFM1 content of the skim milk powder produced from milk with 1.5 μg/liter AFM1 decreased by 2 and 5%, respectively, whereas these rates were 2 and 4%, respectively, for the skim milk powders made from milk with 3.5 μg/liter AFM1 (after adjustment for sample weight). Changes in AFM1 content of milk powder samples were found statistically insignificant (P &gt; 0.05 and P &gt; 0.01) for 3- and 6-month storage periods.


2011 ◽  
Vol 46 (9) ◽  
pp. 1830-1839 ◽  
Author(s):  
Atefeh Amiri-Rigi ◽  
Mohammad A. Mohammadifar ◽  
Zahra Emam-Djomeh ◽  
Mehrdad Mohammadi

1991 ◽  
Vol 58 (3) ◽  
pp. 269-283 ◽  
Author(s):  
Harjinder Singh ◽  
Lawrence K. Creamer

SummaryThe effect of preheat treatment, evaporation and drying in a commercial plant on the denaturation of βlactoglobulin and α-lactalbumin, their incorporation into the casein micelle and the heat stability characteristics of the milks and powders were determined. Preheat treatments between 110 °C for 2 min and 120 °C for 3 min denatured between 80 and 91% of β-lactoglobulin and between 33 and 45% of α-lactalbumin. Evaporation increased the extent of denaturation but spray drying did not increase it further. The incorporation of α-lactalbumin and βlactoglobulin into the micelles was markedly less than the amount that denatured and was not a constant ratio to it. Heat coagulation times at 140 °C of milks, concentrates and powders diluted to the original milk concentration were measured as a function of pH. In general, the greater the collective heat treatment, the shorter the time required to achieve coagulation. Spray drying shifted the peak positions in the pH-heat coagulation time profiles. In contrast, heat coagulation times (measured at 120 °C) of concentrates and powders diluted to 20% total solids content increased with the severity of the preheat treatment. Surprisingly, spray drying markedly increased the heat coagulation times of the diluted concentrates.


1979 ◽  
Vol 46 (4) ◽  
pp. 663-672 ◽  
Author(s):  
James Abbot ◽  
Frank A. Glover ◽  
Donald D. Muir ◽  
Paul J. Skudder

SummaryPowders were prepared from whole and skim-milk using reverse osmosis (RO) as a first stage followed by either evaporation and spray drying or spray drying alone. They were compared with powders made by the conventional method of evaporation and spray drying. Measurements were made of powder solubility, free fat content, whey protein denaturation, vitamin content, powder morphology and bacterial count. The free fat contents of powders prepared from whole milk concentrated by RO were high; otherwise, there were no significant differences in the properties of powders made from milks concentrated initially by RO and those prepared by conventional evaporation. The results indicate that it is feasible to use RO for the manufacture of skim-milk powder and for dried whole milk production where higher free fat levels are not detrimental.


2021 ◽  
Vol 11 (7) ◽  
pp. 3150
Author(s):  
Alicja Barańska ◽  
Aleksandra Jedlińska ◽  
Katarzyna Samborska

Buckwheat honey is proven to demonstrate health beneficial properties; however, its application in the industry is limited due to its high viscosity and syrupy-like consistency. The paper aimed to investigate process performance and physiochemical properties of carrier-reduced buckwheat honey. Honey was spray dried conventionally (inlet/outlet drying temperature: 180 °C/80 °C) and at low drying temperature with dehumidified air application (inlet/outlet drying temperature: 80 °C/45 °C) with maltodextrin as traditional carrier and alternatively with skim milk powder. The results of this study indicate that lowering the humidity of drying air enabled a decrease in carrier content of up to 25% (w/w solids), following powder recovery over 87%, which has not been recorded before for buckwheat honey powders. The results for the physicochemical properties proved that the application of the dehumidified air and skim milk powder as a carrier ameliorated their physiochemical properties and the antioxidant activity. Furthermore, the energy consumption of dehumidified-air-assisted spray drying was investigated as a basis for potential industrial application of this innovative method, which has not been studied in the literature before. The industrial application of this method must be carefully analyzed with regard to its advantages, as the energy consumption is significantly higher than in conventional spray drying.


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