Buttermilk Properties in Emulsions with Soybean Oil as Affected by Fat Globule Membrane-Derived Proteins

The potential utilization of buttermilk from an industrial source was studied in this research, focusing primarily on its composition and use as ingredient in oil-in-water emulsions. Buttermilk contained not only large amounts of caseins and whey proteins, but also material derived from the natural milk fat globule membrane (MFGM). Emulsions made with soybean oil (10% w/w) and buttermilk were stable with a low concentration (about 1% w/w) of buttermilk solids. MFGM-proteins and skim milk proteins did not seem to compete for adsorption at the emulsion interface. The protein adsorbed at the interface was present in an aggregated form and gave a maximum surface coverage of about 8 mg/m².     

MULTIFACTORIAL STUDY OF HAZE FORMATION IN MODEL WINE SYSTEMS

A multifactorial design was used to study the role of protein (Pro), polyphenols (PP), sucrose (Suc), pectin (Pec), potassium (K), and pH in the formation of haze in wine. Model wines (32) containing two levels of each factor plus yeast and nutrients were made and allowed to ferment to 0 Brix. Measurements of transmission at 633 nm (%T) following heating showed that PP, Pro, Pro*PP, Pec, and PP*Pec were all significant factors affecting turbidity. Molecular weight and size determinations by size‐exclusion chromatography‐laser light scattering indicated that molecular weight depended on Suc*Pec, Pro*PP*pH, and Pro*Pec*pH while molecular radius depended on PP*Suc*Pec, Pro, PP*Pec, and Suc*pH. Measurement of protein after filtration showed that Pro, PP, Pro*PP, and Pro*PP*pH were all factors. Laser diffraction studies showed three primary peaks in the range 0.05 ‐ 800 μm. The smallest size range had Pro*pH as a significant factor, while the largest had Pec and Pro*K as factors. These results indicate that a variety of factors are important to haze formation and that measurement of particle size, distribution, and interactions depends upon the instrument used to measure it.     

INTEGRATING OR SEGREGATING ROMA MIGRANTS IN FRANCE IN THE NAME OF RESPECT: A SPATIAL ANALYSIS OF THE VILLAGES D'INSERTION

The French republican model has long promoted an individualist, universal and difference‐blind conception of citizenship. Yet the sociological and historical reality of decolonization and immigration has strained the coherence of this conception and helped to reveal the tension between the universalism of republican principles and the particularistic application of such principles to a specific nation, defined in political and territorial terms. One limit of this model is particularly visible in the spatial management of immigration and segregation trends. Indeed, while French urban planning officially rejects any policies explicitly directed at ethnic minorities, preferring to address social inequalities in spatial terms, it has not prevented French society from pursuing a strict and enduring process of ethno‐racial segregation. Recently, the traditional universalist position has faced a new dilemma with regard to the social and spatial treatment of the Romani populations that have settled in France since the early 2000s. Local authorities have adopted various measures to accommodate and “manage” these populations through specific spatial and administrative devices, some of which are called villages or inclusion villages (villages d'insertion). This article offers a spatial and political analysis of such local policies, focusing on three main ambiguities that characterize this urban device—security function, integrative role, and ethno‐cultural component. The authors show that the villages d'insertion offer a paradigmatic situation in which the usual scales and frames of justice get blurred, and call for a new conception of citizenship, required to promote equal respect to all populations.     

LEMON EXTRACT AS NATURAL PRESERVATIVE IN FRUIT SALAD

In this study the feasibility of using lemon extract to preserve the microbial quality of fresh fruit salad is addressed. In particular, two different packaging strategies were tested: lemon extract directly dissolved into the fruit solution and lemon extract dissolved into a gelatin that was put at the bottom of the salad tray. The microbiological quality decay kinetic of the differently packed cut fruit, stored at 4C, was determined by monitoring spoilage microorganisms for about 20 days. Results show that the active gel in the packaged fruit salad does not seem to affect to a great extent the growth of the investigated microorganisms; on the contrary, the use of the active solution seems to be effective in inhibiting the growth of the natural spoilage microflora, preserving the microbial quality of the packaged product for a longer time.

PRACTICAL APPLICATIONS

The results obtained in this research could be advantageously used by industry as a request of consumer demand for high-quality convenience food. The present research represents a starting point to develop high safety packaging systems able to prolong the shelf life of fresh cut fruit. Encouraging results on the use of natural products to control postharvest rotting indicate that it is possible to substitute the synthetic compounds with preservatives safer for man and environment.     

OPTIMIZING STABILITY OF ORANGE JUICE FORTIFIED WITH WHEY PROTEIN AT LOW pH VALUES

Abstract The influence of temperature, heating time and pH on the stability of whey protein-fortified Valencia orange juice was determined by uronic acid content, degree of esterification (DE), % transmission measurements (%T) and capillary electrophoretic analysis of the juice-protein supernatants. Uronic acid content and charge of pectins showed no significant change in heat-treated samples with added proteins. The %T decreased with decreasing pH and increasing temperature and heating time for α-lactalbumin (α-lac), β-lactoglobulin (β-lg) and whey protein isolate (WPI). The lowest transmission values were shown at pH 3.0 and 85C. Capillary electropherograms confirmed more extensive juice-protein interactions in WPI and β-lg added juices than in those containing α-lac, especially at low pH, resulting in more stable juice-protein mixtures.     

RESPONSE SURFACE MODEL FOR EFFECTS OF TEMPERATURE, WATER ACTIVITY AND pH ON GERMINATION OF BACILLUS CEREUS SPORES

A response surface model was developed for effects of temperature (20 to 40C), pH (4.5 to 6.5) and water activity (a_w) (0.94 to 0.99) on germination of Bacillus cereus ATCC 11778 spores. Germination depended, to varying extents, on the interactions among the independent variables and complexity of the medium. In particular it was affected (P < 0.05) by interactions of a_w with temperature and pH and by temperature in its quadratic term. The model was validated against data not used in its development. Mean absolute relative error of predictions (model accuracy) was 22.8% in model systems and 10.17% in real systems. Bias factors were 0.887 and 0.922 for model and real systems, respectively. Results indicated that the model developed was "fail safe" and provided reliable predictions of germination of B. cereus.