Engelsen, Søren Balling

Jespersen, Birthe P Møller

Mikkelsen, Mette Skau

Thompson, Cecilia S.

English

Copenhagen University Research Information System

u n i ve r s i t y  o f  co pe n h ag e n  Københavns UniversitetLifestyle foods - investigation of ß-glucan enriched yoghurtsMikkelsen, Mette Skau; Thompson, Cecilia S.; Jespersen, Birthe P Møller; Engelsen, SørenBallingPublication date:2004Document versionEarly version, also known as pre-printCitation for published version (APA):Mikkelsen, M. S., Thompson, C. S., Jespersen, B. P. M., & Engelsen, S. B. (2004). Lifestyle foods - investigationof ß-glucan enriched yoghurts.Download date: 02. Feb. 2020D E P A R T M E N T   O F   F O O D   S C I E N C EF A C U L T Y   O F   L I F E   S C I E N C E S U N I V E R S I T Y   O F   C O P E N H A G E NLifestyle foods- investigation of β-glucan enriched yoghurtsMette Skau Nielsena†, Cecilia S. Thompsonb, Birthe M. Jespersena and Søren B. EngelsenaaQuality & Technology, bDairy Technology† Presenting author. E-mail: skau@life.ku.dkBackgroundHealth benefits and hydrocolloid functionality of mixed linkage (1→3,1→4)-β-D-glucan (BG) dietary fibres from cereals make them interesting food constituents (1). The texture promoting effect of cereal BG on dairy products have been reported previously (2), but problems with phase separation and product instability have to be solved before the possible health beneficial effects from a BG dairy product can be fully utilised.We have studied the influence of:- β-glucan concentration- pH - storage time - milk protein content - an emulsifieron level of syneresis in yoghurts to evaluate the interaction between BG and milk proteins.AimThe study will contribute to the understanding of soluble barley β-glucanfibres in milk formulations designated to be used as a health promoting functional food.References1 Wood, P.J. (2004), Trends food sci. tech., 15, 313-320; 2 Brennan, C.S. & Tudorica, C.M.(2008), J. food sci. tech., 43, 824-833; 3 Spreer, E. (1998), Milk & dairy product tech., Marcel Dekker Inc., NY, USAYoghurt manufactureTo improve gel characteristics and avoid syneresis yoghurts are often stabilised with hydrocolloids e.g. pectin or xanthan gum. Also dry matter content and pH can be modified to improve product stability (3). In this study yoghurts were manufactured from skimmed milk powder, SMP (10%, 15% w/v) and acidified with glucono-δ-lactone, GDL (pH 3.8, 4.2, 4.6). The barley β-glucan, Glucagel® (0.5%, 1.5%) containing yoghurts were compared to non-supplemented and inulin, Orafti® (0.5%, 1.5%) supplemented controls. Measurements were conducted on fresh yoghurt samples and after 8 days of storage. ConclusionsBeta-glucan at levels 0.5-1.5% in yoghurt interferes with the casein gel network resulting in increased syrenesis. Varying the pH did not improve the stability of the BG yoghurts.  Hydration of the BG fibres and increasing the dry matter content from 10% to 15% SMP improved product stability. Addition of an emulsifier decreased syrenesis levels suggesting that interactions between the BG and casein gel network is of hydrophobic rather than electrostatic nature.    Syneresis levels for yoghurts made from 10% skimmed milk powder with addition of β-glucan (BG) or inulin (I) at levels 0.5% or 1.5%. pH is varied at three levels (3.8, 4.2, 4.6) and measurements are conducted on fresh samples (day 0) and one week old samples (day 8).020406080control BG 0.5% BG 1.5% I 0.5% I 1.5%syneresis (%)Day 0020406080control BG 0.5% BG 1.5% I 0.5% I 1.5%pH 4.6pH 4.2pH 3.8Day 8SyrenesisYoghurts made with 10% SMP and inulin (I)showed low, and similar, syneresis levels compared to control samples. Thus, inulin at the studied levels, and under the given conditions does not interfere with the casein gel network. Yoghurts made with 10% SMP and β-glucan(BG) showed consequently higher syneresislevels compared to control and inulin samples - the 0.5% BG yoghurt with maximum levels. The decreased levels of syneresis after 8 days of storage for samples with 1.5% BG suggests that increased hydration of the fibres results in increased liquid retention.   Effect of dry matter contentAn increase of SMP to 15% rendered improved results for the BG supplemented samples with less syneresis, but values were still not comparable to control samples.024681012control BG 0.5% BG 1.5%syneresis (%) pH 4.6pH 4.2pH 3.8Syneresis levels for fresh yoghurt samples (day 0) made from 15% skimmed milk powder with addition of β-glucan (BG) at levels 0.5% or 1.5%. pH is varied at three levels (3.8, 4.2, 4.6).Effect of an emulsifier Measurements of fresh yoghurts with 0.5% BG and addition of Tween®20 showed a decrease in syneresis levels with increasing amount of Tween®20.  4045505560control T 1% T 2% T 3%syneresis (%)Syneresis levels for fresh yoghurt samples (day 0, pH 4.2) made from 10% skimmed milk powder with addition of 0.5% BG and Tween®20 (T) at levels 1%, 2% or 3%. 

Lifestyle foods - investigation of ß-glucan enriched yoghurts

https://curis.ku.dk/portal/files/40471459/PosterICC2009_MSN.pdf

Lifestyle foods - investigation of ß-glucan enriched yoghurts

Abstract

Similar works

Full text

Available Versions

Copenhagen University Research Information System