Rheological Properties and Microstructure of Acid Milk Gels as Affected by Fat Content and Heat Treatment

The effects of fat content and the supplementation of milk with Sodium Caseinates (SCN) and Whey Proteins Concentrates (WPC) on the rheological and sensory properties of stirred yogurt made from buffalo milk were investigated. Whether the heat treatment of the milk affected the rheological behavior and the sensory characteristics of the samples was also evaluated. Principal Component Analysis (PCA) was used to assess in detail the relative contribution of whey proteins, caseins and fat on the rheological properties and sensory characteristics of the samples. Furthermore, it related the instrumental and objective sensory data to consumer perception (hedonic response of non-trained panelists). The objective acidity and white color intensity were positively correlated and increased with increasing casein content. Fat interacted synergistically with caseins to increase all the hedonic attributes, apart from odor. As far as rheological properties are concerned, elastic modulus (G'), instantaneous elasticity (Gg), retarded elasticity (GR) and Newtonian viscosity (?0) were positively correlated with increasing casein content. However, tan ? was negatively correlated with the aforesaid attributes and increased with increasing fat content. Whey proteins in the presence of fat determined the magnitude of flow behavior index (n). The lactic acid concentration (%) and the b component of color (yellow color intensity) were affected positively by SCN and WPC addition but in the absence of fat. In all regression equations the effect of process temperature was found to be insignificant. Finally, the consumer-optimized composition of the fat and the added SCN can be used to formulate a marketable product.

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Effect of interactions between denatured whey proteins and casein micelles on the formation and rheological properties of acid skim milk gels

Journal of Dairy Research ◽

10.1017/s0022029998003057 ◽

1998 ◽

Vol 65 (4) ◽

pp. 555-567 ◽

Cited By ~ 162

Author(s):

JOHN A. LUCEY ◽

MICHELLE TAMEHANA ◽

HARJINDER SINGH ◽

PETER A. MUNRO

Keyword(s):

Heat Treatment ◽

Rheological Properties ◽

Loss Tangent ◽

Whey Proteins ◽

Skim Milk ◽

Casein Micelles ◽

Heated Milk ◽

Tan Δ ◽

Reconstituted Milk ◽

Acid Milk Gels

The effect of interactions of denatured whey proteins with casein micelles on the rheological properties of acid milk gels was investigated. Gels were made by acidification of skim milk with glucono-δ-lactone at 30°C using reconstituted skim milk powders (SMP; both low- and ultra-low-heat) and fresh skim milk (FSM). The final pH of the gels was ∼4·6. Milks containing associated or ‘bound’ denatured whey proteins (BDWP) with casein micelles were made by resuspending the ultracentrifugal pellet of heated milk in ultrafiltration permeate. Milks containing ‘soluble’ denatured whey protein (SDWP) aggregates were formed by heat treatment of an ultracentrifugal supernatant which was then resuspended with the pellet. Acid gels made from unheated milks had low storage moduli, G′, of <20 Pa. Heating milks at 80°C for 30 min resulted in acid gels with G′ in the range 390–430 Pa. The loss tangent (tan δ) of gels made from heated milk increased after gelation to attain a maximum at pH ∼5·1, but no maximum was observed in gels made from unheated milk. Acid gels made from milks containing BDWP that were made from low-heat SMP, ultra-low-heat SMP and FSM had G′ of about 250, 270 and 310 Pa respectively. Acid gels made from milks containing SDWP that were made from ultra-low-heat SMP or FSM had G′ values in the range 17–30 Pa, but gels made from low-heat SMP had G′ of ∼140 Pa. It was concluded that BDWP were important for the increased G′ of acid gels made from heated milk. Addition of N-ethylmaleimide (NEM) to low-heat reconstituted milk, to block the —SH groups, resulted in a reduction of the G′ of gels formed from heated milk but did not reduce G′ to the value of unheated milk. Addition of 20 mm-NEM to FSM, prior to heat treatment, resulted in gels with a lower G′ value than gels made from reconstituted low-heat SMP. It was suggested that small amounts of denatured whey proteins associated with casein micelles during low-heat SMP manufacture were probably responsible for the higher G′ of gels made from milk containing SDWP and from milk heated in the presence of 20 mm-NEM, compared with gels made from FSM.

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Rheological properties of acid milk gels as affected by the nature of the fat globule surface material and heat treatment of milk

International Dairy Journal ◽

10.1016/s0958-6946(99)00123-5 ◽

1999 ◽

Vol 9 (8) ◽

pp. 537-545 ◽

Cited By ~ 81

Author(s):

Y.H. Cho ◽

J.A. Lucey ◽

H. Singh

Keyword(s):

Heat Treatment ◽

Rheological Properties ◽

Surface Material ◽

Fat Globule ◽

Acid Milk Gels

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Tuning the rheological properties of protein-based oleogels by water addition and heat treatment

Food Hydrocolloids ◽

10.1016/j.foodhyd.2017.11.043 ◽

2018 ◽

Vol 79 ◽

pp. 100-109 ◽

Cited By ~ 16

Author(s):

Auke de Vries ◽

Demi Jansen ◽

Erik van der Linden ◽

Elke Scholten

Keyword(s):

Heat Treatment ◽

Rheological Properties ◽

Water Addition

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INFLUENCE OF FAT CONTENT ON RHEOLOGICAL PROPERTIES OF MOLTEN ICE CREAM COMPOUND COATINGS AND THICKNESS OF SOLIDIFIED PRODUCTS

Journal of Food Process Engineering ◽

10.1111/j.1745-4530.2008.00342.x ◽

2011 ◽

Vol 34 (1) ◽

pp. 144-159 ◽

Cited By ~ 6

Author(s):

DORRA GHORBEL ◽

NAZIHA BARBOUCHE ◽

HAÏTHEM RIAHI ◽

AHMED BRAHAM ◽

HAMADI ATTIA

Keyword(s):

Rheological Properties ◽

Ice Cream ◽

Fat Content ◽

Compound Coatings

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Effects of reducing fat content on the proteolytic and rheological properties of Cheddar-like caprine milk cheese

Small Ruminant Research ◽

10.1016/j.smallrumres.2012.11.034 ◽

2013 ◽

Vol 110 (1) ◽

pp. 46-51 ◽

Cited By ~ 5

Author(s):

D.L. Van Hekken ◽

Y.W. Park ◽

M.H. Tunick

Keyword(s):

Rheological Properties ◽

Fat Content ◽

Caprine Milk

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Effect of Temperature and Used Ingredients on Rheological Parameters of Pancake Dough

Acta Technologica Agriculturae ◽

10.2478/ata-2013-0016 ◽

2013 ◽

Vol 16 (3) ◽

pp. 63-66

Author(s):

Peter Hlaváč ◽

Monika Božiková

Keyword(s):

Rheological Properties ◽

Dynamic Viscosity ◽

Kinematic Viscosity ◽

Fat Content ◽

Effect Of Temperature ◽

Rheological Parameters ◽

Rotational Viscometer ◽

Two Samples ◽

Dynamic And Kinematic Viscosity ◽

Temperature Dynamic

Abstract This paper presents the selected rheological properties of pancake dough such as dynamic and kinematic viscosity and fluidity. The effect of used ingredients and temperature on rheological properties is investigated. Measurements were performed on three pancake dough samples. In two samples, there was used milk with a different fat content, and in the third sample, all ingredients were in a powder state. A digital rotational viscometer Anton Paar DV-3P was used for measuring the rheological properties. The principle of viscometer measurement is based on the dependence of sample resistance to probe rotation. Results of measurements are shown as graphical dependencies of rheological parameters on temperature. Exponential functions were used to express the dependencies of all rheological parameters on temperature. Dynamic and kinematic viscosity decreased, and fluidity increased with temperature. The highest values of dynamic viscosity were obtained for pancake dough from powder ingredients. A higher fat content of used milk caused higher values of dynamic viscosity.

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Effect of Heat Treatment on Rheological Properties of Bambangan (Mangifera pajang kosterm) Fruit Juice

Advances in Agricultural and Food Research Journal ◽

10.36877/aafrj.a0000115 ◽

2020 ◽

Vol 1 (2) ◽

Author(s):

Jumardi Roslan ◽

Hay Chye Ling ◽

Mohd Dona Sintang ◽

Suryani Saallah

Keyword(s):

Heat Treatment ◽

Rheological Properties ◽

Fruit Juice ◽

Market Potential ◽

Pseudoplastic Fluid ◽

Treatment Conditions ◽

High Temperature Short Time ◽

Long Time ◽

Mild Temperature ◽

Short Time

Bambangan (Mangifera pajang Kosterm) is an indigenous fruit that can be found in Borneo Island including Sabah and Sarawak (Malaysia), Kalimantan (Indonesia), and Brunei. Besides being freshly eaten, the pulp of bambangan fruit can be processed for juice production to expand its market potential. During the processing of fruit juice, the application of heat treatment such as pasteurization and sterilization might influence their rheological behavior. Thus, the present study aims to investigate the effect of heat treatment on the rheological properties of bambangan fruit juice (BFJ). The freshly squeezed BFJ was subjected to different heat treatment conditions; sterilization (121°C, 3 minutes), mild temperature long time (MTLT) pasteurization (65°C, 15 minutes), and high temperature short time (HTST) pasteurization (90°C, 1 minute). Rheological analysis of the heat-treated BFJ was performed using a rheometer at a shear rate ranging from 1 to 250 s-1 and a temperature between 5 °C to 70 °C. Pasteurization at 90 °C for 1 minute (HTST) was found to be the most suitable heat treatment for the BFJ. At this condition, the BFJ exhibited a non-Newtonian pseudoplastic fluid behavior (n < 1), fitted well with the Herschel-Bulkey model. The value of parameters obtained from Herschel-Bulkley equation for HTST treatment of bambangan juice were n= 0.83, k= 0.32 and yield stress= 3.96. The viscosity values of HTST bambangan juice at the temperature of 5, 20, 40 and 70 °C were 3.53, 2.33, 1.53 and 1.76 Pa.s respectively. This rheological information is of fundamental importance in optimizing equipment design, process control, and sensory evaluation.

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