How to reduce the energy costs of food and dairy products to spray drying?

The most frequently used technique for dehydration of dairy products is spray drying. This is an effective method to preserve biological products as it does not involve prolong exposure of materials to severe heat treatment. Due to the variety and complexity of the concentrates to be dried, a more rigorous understanding of spray-drying based on physico-chemical and thermodynamic properties is necessary. At the same time, the current state of the art did not allow easy determination of the parameters of spray-drying of dairy products prior to drying, except from performing several complex and expensive experiments with pilot-scale spray-dryer. Nevertheless, recent advances in the understanding of product behavior toward water transfer with the development of a desorption method makes it possible to give several answers to the following question: What is the best strategy to anticipate the behavior of concentrate toward drying and to improve the process, the economy and the quality of the dairy powders? The strategical approach can be developed on the knowledge of the thermodynamic parameters of the spray dryer coupled to physico-chemical characteristics of the concentrate. The software SD2P® (Spray Drying Parameters Simulation & Determination) developed by Schuck et al. (2009) is a way, among others, to predict the value of these parameters when they are not known. The combined results provide more precise determination of spray-drying parameters (including inlet/outlet air temperature, mass/powder flow rate, powder temperature, etc.), powder state during spray-drying (stickiness) and the cost of spray-drying with respect to weather conditions. Several cases will be presented to show the interest of this strategy in order to anticipate the spray-drying parameters and the powder behavior. Please click Additional Files below to see the full abstract

Technological breakthrough and innovation in the production of whey powders, with 30-40% reduction in energy costs

There are two essential stages in the elimination of water for the production of whey and permeate powders: concentration by vacuum evaporation followed by spray drying. These two operations alone represent 25% of the energy consumed by the French dairy industry, the major part of which is due to the drying stage. Indeed, 96.7% of the whey water is removed during the vacuum evaporation/concentration stage, whereas drying, which removes only 3.3% of the water, requires 31% of the total energy used over the entire process. One possible way to reduce energy consumption would be for the product to enter the drying tower at a higher level of dryness. We therefore propose replacing the drying tower with rotating evaporators, i.e. equipment adapted to highly viscous products able to pass from a liquid state to a granular state by a continuous process. Please click Additional Files below to see the full abstract

How does particle size influence caking in lactose powder?

Particle size distribution (PSD) is known to influence product properties such as flowability andcompressibility. When producing crystalline lactose, different steps can affect the PSD of the finalpowder. The aim of this study was to investigate the influence of PSD on caking and the mechanismsinvolved. Smaller particles showed higher moisture sorption and a greater caking tendency, measured bydynamic vapor sorption and ring shear testing, respectively. Therefore, moisture sorption isothermsappeared as a valuable tool to predict the effect of PSD on humidity caking, as confirmed by the results ofring shear testing. Controlling the amount of fines, characterized by a higher content of impurities, alarger specific surface area and a broader span of the PSD, was found critical to limit caking. Moreprecisely, both the total surface area and the span of the PSD require close attention as they cansignificantly influence humidity and mechanical caking

New process for the production of permeate powders without spray dryer

An innovative process scheme for the production of dairy permeate powders was tested at the pilot scale. It includes: (i) overconcentration of the permeate concentrate from 60 to 80% w/w dry matter (DM) content; (ii) granulation of the overconcentrate with powder up to 88% DM; and (iii) drying of the granules up to 97% DM.The quality of the resulting powder was comparable to a standard powder produced using conventional technologies. Furthermore, considering energy required for water removal, the new process led to significant savings: they were estimated in the range of 10.7 to 23.5% and up to 32% when taking into account the whole production process or the drying step alone, respectively

Nanofiltration of lactic acid whey: A process to improve the dryability and the quality of powder

Nanofiltration of lactic acid whey: A process to improve the dryability and the quality of powder. 6. European Drying Conference: EuroDrying 201

Microstructure and chemical composition of camel and cow milk powders’ surface

This study aimed at investigating the chemical composition and microstructure of spray dried camel and cowmilk powders' surfaces with two different milk-fat contents (1 and 20g 100 g−1). The SEM (Scanning ElectronMicroscopy) micrographs showed that spherical particles with a ‘brain’-type surface for both milk powders wereproduced. The surface roughness (Ra) of whole (WDMP) and skimmed (SDMP) camel milk powders(Ra=7.6 ± 0.4 nm and 5.6 ± 0.7 nm, respectively) were significantly lower as compared with the partiallyskimmed (PSCMP) and skimmed (SCMP) cow milk powders. The XPS (X-ray Photoelectron Spectroscopy)analysis highlighted that the surface of skimmed camel milk powders contained twice the lactose amount(17.7 ± 0.8%) as compared to cow milk powders (8.7 ± 0.4%). Furthermore, both milk powders showed theoverexposure of proteins and fats at their surfaces regardless of the fat content. The CLSM (Confocal LaserScattering Microscopy) micrographs highlighted that most of the camel milk fat globules were encapsulated bythe proteins near the powder surface. Camel milk fat behavior during particle formation was attributed to theirlower size distribution and their higher crystallization temperature

Influência do equipamento na cinética de cristalização do soro concentrado

O principal objetivo deste trabalho consistiu na determinação do efeito do tipo de cristalizador na eficiência da cristalização da lactose em soro de leite concentrado, utilizando dois equipamentos que dispõem de diferentes formas de agitação (tanque 1 – agitador central e tanque 2 – agitador periférico), mantendo as demais condições de cristalização constantes, como: taxa de resfriamento; temperatura; velocidade de agitação; tempo de cristalização e teor se sólidos solúveis por tratamento. A maior taxa de cristalização no soro concentrado foi obtida pelo emprego da agitação central [Tempo (min) = 0,1927 (% cristalização da lactose) + 21,681] e [Tempo (min) = -0,06 (oBrix) + 51,233] sob a taxa de resfriamento de -0,34 oC ± 0,05 oC por minuto, durante a primeira hora e alcançando a temperatura de 25,8o ± 1,2 oC após 4 horas. A agitação central promoveu as maiores taxas de cristalização em soro concentrado com 50 oBrix, 55 oBrix e 60 oBrix. Observou-se que mudanças nas condições de cristalização do soro concentrado (em diferentes tanques) e no teor de sólidos solú­veis implicam na obtenção de pós com diferentes propriedades de reidratação, de adesão e com teores distintos de lactose cristalizada, impactando na conservação durante o prazo de validade.The main objectives of this project were to determine the effect of the crystallizer design on lactose crystallization efficiency in concentrated whey. Two different crystallizers were used, one presenting a central agitation (tank 1) and the other presenting a peripheral agitation (tank 2). All others crystallization parameters were kept constant such as cooling rate; temperature; stirring speed; crystallization time and concentration of soluble solids by treatment.The best rate for lactose crystallization in concentrated whey was obtained applying central stirring and 55 oBrix [Time (min) = 0.1927 (% lactose crystallization) + 21.681] and [Time (min)= -0.06 (oBrix) + 51.233] under the cooling rate of -0.34 oC ± 0.05 oC per minute during the first hour and achieving the final temperature of 25.8o ± 1.2 oC after 4 hours, central stirring promoted highest rates of lactose crystallization in concentrated whey with 50, 55 and 60 oBrix.The type of Tank for crystallization and the dry matter content in concentrated whey affect whey powder rehydration, stickiness into the chamber, different levels of lactose crystallization and storage of the powder

Hidrolise da lactose e producao de leite em po : aspectos technologicos

The food industry has the challenge and the opportunity to develop new products with reduced or low lactose content in order to meet the needs of a growing mass of people with lactose intolerance. The manufacture of spray dried products with hydrolyzed lactose is extremely challenging. These products are highly hygroscopic,which influence the productivity and conservation of the powders, not to mention the undesirable and inevitable technological problem of constant clogging of drying chambers. The aim of this study was to evaluate the effect of different levels (0%, 25%, 50%, 75% and > 99%) of enzymatic lactose hydrolysis on the production andstorage of whole milk powder. The samples were processed in a pilot plant and characterized in relation to their composition analysis; to their degree of hydrolysis of lactose; and to their sorption isotherms. The results indicated the hydrolysis of lactose may affect the milk powder production due to a higher extent of powderadhesion within the spray dryer chambers and due to a higher tendency to absorb water during storage.A indústria de alimentos tem como desafio e oportunidade desenvolver novos produtos com reduzido ou baixo teor de lactose, a fim de atender uma crescente massa de portadores de má digestão da lactose. A secagem dos produtos com lactose hidrolisada é um desafio tecnológico devido a higroscopicidade dos mesmos, influenciando na produtividade, no entupimento das câmaras e na conservação dos pós. O objetivo deste estudo foi avaliar o efeito de diferentes níveis de hidrólise enzimática da lactose (0%, 25%, 50%, 75% e > 99%), na produção e estocagem de leite em pó integral utilizando como ferramentas de caracterização dos produtos fabricados em planta piloto a análise de composição, o controle do grau de hidrólise e as isotermas de sorção. Todos os resultados indicam que a hidrólise da lactose afeta a produção do leite em pó por aumentar a adesão no spray dryer e a absorção de umidade durante a estocagem

The N-terminus of FILIA Forms an Atypical KH Domain with a Unique Extension Involved in Interaction with RNA

FILIA is a member of the recently identified oocyte/embryo expressed gene family in eutherian mammals, which is characterized by containing an N-terminal atypical KH domain. Here we report the structure of the N-terminal fragment of FILIA (FILIA-N), which represents the first reported three-dimensional structure of a KH domain in the oocyte/embryo expressed gene family of proteins. The structure of FILIA-N revealed a unique N-terminal extension beyond the canonical KH region, which plays important roles in interaction with RNA. By co-incubation with the lysates of mice ovaries, FILIA and FILIA-N could sequester specific RNA components, supporting the critical roles of FILIA in regulation of RNA transcripts during mouse oogenesis and early embryogenesis