Characterization of Hazelnut Milk Powders: A Comparison of Spray-Drying and Freeze-Drying

Abstract

Production of hazelnut milk powder (HMP) was investigated using maltodextrin (MD) as supporting material. Spray-drying and freeze-drying techniques were used to obtain the powder material. MD was added at concentrations of 5%, 10% and 15% (w/w) prior to drying. The powder properties were evaluated by determining flowing properties (Hausner ratio and angle of repose), thermal behaviour using DSC, molecular properties using FTIR, solubility and zeta potential. Hausner Ratio for both spray dried (SDHMP) and freze-dried (FDHMP) samples varied from 1.30 to 1.64 corresponding to very poor flow. The FDHM powder samples exhibited slightly lower Hausner Ratio values than SDHM powders. FTIR spectras showed that both SDHM and FDHM exhibited similar absorbance characteristics with slight differences. Lower endothermic transition temperatures were recorded from FDHMP when compared to SDHMP. The solubility in water for both powder samples ranged from 20 to 65 % depending on the drying method and MD content. Based on the residual moisture content, water activity, solubility and flowability, spray drying process was found to produce better quality powders compared to freeze drying process.

Physical Properties of Protein Extract Powder From Stale Bread and Evaluation of Its Use in Wheat Bread Containing Chickpea Flour

“…Then 150 taps (compression) were performed using a glass rod at a constant speed on the powder sample while in the graduated cylinder. The tapped density was calculated by dividing the mass by the volume of the sample after the taps (Ermis et al 2018). The flow property of protein powder was evaluated by the Hausner ratio (HR) using Eq.…”

Püskürtmeli̇ Kurutucu İle Yaği Alinmiş Ayçi̇çeği̇ Protei̇n Ekstrakti Tozu Üreti̇mi̇: Fonksi̇yonel Özelli̇kleri̇ Ve Toz Karakteri̇zasyonu

“…3) was calculated from the bulk (ρb) and tapped density (ρt) values (Hausner, 1967). The flow behaviour of SPP was evaluated based on the data given in Table 1 ( Ermis et al, 2018).…”

“…The absorbance values were obtained from 4000 cm -1 to 600 cm -1 . Crystal surface was cleaned using a piece of a soft tissue paper wetted with ethanol and a background (air) scan was done prior to analysis (Ermis et al, 2018). The thermal behaviour of SPP was characterized using a Shimadzu differential scanning calorimeter, DSC-60 Plus (Shimadzu Co. Ltd., Kyoto, Japan).…”

“…Around 2-3 milligrams of sample were sealed in a hermetic aluminium pan and heated from 25 to 100 °C at a rate of 10 °C/min. An empty aluminium pan was considered as reference (Ermis et al, 2018).…”

“…Determination of flow properties is needed to predict the behaviour of a powder material during processing steps such as storage, handling, transportation and discharge to prevent flow problems (i.e. rat-holing, arching, erratic flow and flooding) (Ermis et al, 2018). The compressibility of SPP was found to be high and this might be attributed to the closer particle packing, irregular particle properties and increase in inter-particle surface contact (Amagliani et al, 2016).…”