Addition of buttermilk powder to yogurt: effects on particle size, microstructure and texture

The addition of buttermilk powder as partial fat replacer in yogurt formulations with constant dry matter was investigated. Three formulations of yogurt were produced containing 0% (T1), 1.36% w·w-1 (T2) and 3.34% w·w-1 (T3) of buttermilk powder in the final product. Particle size and pH variation were monitored during fermentation; scanning electron microscopy and texture profile analysis were performed in the final product. The control sample showed larger particle size on the day after production and at the end of fermentation, as well as a more compact network microstructure with a smaller average pore size. Compared to the prototypes with added buttermilk the control sample showed greater higher firmness. Buttermilk powder could act as fat replacer for yogurt but favors the formation of a less compacted network microstructure, with large pores, less springiness after 21 days, and less hardness in the two evaluated times (21 and 42 days).

Effect of buttermilk and skimmed milk powder on the properties of low-fat yoghurt

The aim of the study was to determine the potential of using buttermilk and skimmed milk powders as additives to standardize the dry matter content of milk in the production of low-fat yoghurt. A batch of yoghurt was produced using a starter culture of Lactobacillus delbruecki ssp. bulgaricus and Streptococcus thermophilus. The rates of milk acidification and pH levels were similar for both variants of yoghurt. After chilled storage (21 days), the yoghurt produced from milk supplemented with buttermilk powder was found to contain higher (P ≤ 0.05) levels of lactic acid (1.179%) than that supplemented with skimmed milk (1.154%). The use of buttermilk powder allowed reducing (not significantly, P > 0.05) syneresis in the stored yoghurt. The milk fat in the buttermilk–supplemented yoghurt showed lower (P ≤ 0.05) phospholipids content and exhibited slightly higher phospholipids loss during storage than the yoghurt produced from milk with addition of milk powder. No differences were found between the profile of fatty acids between the yoghurts enriched with skimmed milk powder and those enriched with buttermilk powder. Buttermilk can be used as an additive to produce a novel yoghurt type with modified functional features. Research Highlights The use of buttermilk powder did not affect fermentation process, however increased lactic acid content and water-holding capacity of yoghurt. The yoghurts with added buttermilk contained less phospholipids when compared with yoghurts supplemented with milk powder. Buttermilk powder can be incorporated as an ingredient in production of novel yoghurt type with improved functional features.

Comparison of some functional properties and protein profiles of different protein sources with egg components

Emulsifying and foaming properties of plant and animal-sourced proteins; wheat protein hydrolysates (WP1, WP2, and WP3), potato protein isolates (PP1, PP2), pea proteins isolates (PeP1, PeP2), whey protein concentrate (WPC), and buttermilk powder (BMP) were compared with the egg white powder (EWP) and egg yolk powder (EYP). Foaming capacity, stability, emulsion activity, stability, heat stability, morphology, and electrophoretic protein profiles were determined. The proteins representing competitive emulsifying functions were PeP1, WPC, and BMP. Heat treatment for 30 min at 80°C remarkably reduced the emulsion activity (EA) of EYP. Our findings demonstrated that patatin-rich potato protein (PP1), an allergen-free and vegan option, has great potential to replace the foaming function of the egg white. The relationship between the protein profiles of the samples and their functional properties was further discussed in detail.

Texture, colour and sensory properties of non-fat yoghurt as influenced by tara gum or combinations of tara gum with buttermilk powder

The texture, colour and sensory properties of non-fat yoghurts prepared with different tara gum concentrations (0.25, 0.50 and 1.0 gL-1) and different tara gum (TG) with buttermilk powder (BP) combinations (0.25+10, 0.50+10 and 1.0+10 gL-1) were investigated during storage. While addition of 0.25 and 0.50 gL-1 of tara gum caused an increase in firmness, consistency, cohesiveness, viscosity index of yoghurt samples, use of 1 gL-1 of tara gum and combinations of tara gum with buttermilk powder led to a decrease in these properties. During the storage period, increasing the concentration of tara gum resulted in significant decrease in L* and a* values, significant increase in b* value in yoghurt. Sensory properties of non-fat yoghurts supplemented with 0.25 and 0.50 gL-1 did not significantly differ from those of control yoghurts. In contrast, use of 1 gL-1 of tara gum and combinations of tara gum and buttermilk powder caused a significant decrease of sensory properties of non-fat yoghurt.

Prevalence of Cronobacter spp. and Salmonella in Milk Powder Manufacturing Facilities in the United States

ABSTRACT The U.S. Food and Drug Administration (FDA) conducted a sampling assignment in 2014 to ascertain the prevalence of Cronobacter spp. and Salmonella in the processing environment of facilities manufacturing milk powder. Cronobacter was detected in the environment of 38 (69%) of 55 facilities. The average prevalence of Cronobacter in 5,671 subsamples (i.e., swabs and sponges from different facility locations) was 4.4%. In the 38 facilities where Cronobacter was detected, the average prevalence of positive environmental subsamples was 6.25%. In 20 facilities where zone information of the sampling location was complete, Cronobacter was most frequently detected in zone 4, followed by zone 3, then zone 2, with zone 1 yielding the lowest percentage of positive samples. The prevalence of Cronobacter across the zones was statistically different (P < 0.05). There was no significant association between product type (i.e., lactose, whey products, buttermilk powder, and nonfat dried milk) and prevalence of Cronobacter in the facility. Salmonella was detected in the environment of three (5.5%) of the 55 facilities; all three facilities produced dried whey product. The overall prevalence of Salmonella in 5,714 subsamples was 0.16%. In facilities in which Salmonella was detected, the average prevalence was 2.5%. Salmonella was most frequently detected in zone 4, followed by zone 3. Salmonella was not detected in zone 1 or zone 2. The disparity between Salmonella and Cronobacter prevalence indicates that additional measures may be required to reduce or eliminate Cronobacter from the processing environment. HIGHLIGHTS

Effect of milk fat globule membrane materials on the crystallization behaviour in dairy recombined cream

Milk fat globule membrane (MFGM) fragments were isolated from reconstituted buttermilk (BM-MFGM) and from buttermilk whey (whey-MFGM) and used to make recombined cream. Besides, the commercial dairy ingredient, Lacprodan® PL20, a material rich in milk polar lipids and proteins, was used as another MFGM source. Recombined cream was prepared by homogenizing 35% (w/w) anhydrous milk fat into an aqueous phase containing individual BM-MFGM, Whey-MFGM, Lacprodan® PL20, or buttermilk powder (BMP) or a mixture of MFGM materials and BMP (4:6, w/w). The effect of MFGM on the fat crystallization behaviour, shear-induced partial coalescence was investigated and compared to those of natural cream and recombined cream made with BMP. It was found that the physicochemical properties of recombined cream were strongly affected by the MFGM source. Shear-induced partial coalescence of WheyMFGM40 was slower compared to that of natural cream. Amongst the four emulsifier materials used in this study, Whey-MFGM showed a similar crystallization behaviour to natural cream.