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Analytical assessment of the intense heat load of whipping cream, coffee cream, and condensed milk at retail in Austria and Germany

View Article: PubMed Central - PubMed

ABSTRACT

Time temperature integrators (TTIs) are useful tools in estimating the heat load applied on differently processed dairy products. The objective of this study was to analyze and assess three TTIs – lactulose, furosine, and acid-soluble β-lactoglobulin (β-Lg) – in 70 high heated dairy products at retail in Austria and Germany comprising whipping cream, coffee cream/milk, and condensed milk products. While β-Lg was not appropriate to evaluate the heat load of these products, furosine and especially lactulose increased with rising intensity of heat treatment, and are appropriate to distinguish between several heating categories analyzed. Pasteurized (n = 8) and “heat treated” (n = 5) whipping cream samples showed lowest furosine (48 ± 14/ 45 ± 19 mg.100 g−1 protein) and low lactulose (29 ± 10/57 ± 28 mg.L−1) concentrations, followed by ESL whipping cream (n = 10), ESL coffee cream (n = 1), and UHT whipping cream (n = 10) (furosine = 72 ± 37/71/161 ± 30 mg.100 g−1 protein; lactulose = 56 ± 41/161/195 ± 39 mg.L−1), respectively. Sterilized condensed milk samples (n = 14) showed the highest concentrations of both TTIs and could be clearly separated from UHT treated samples (n = 5) (furosine = 491 ± 196/216 ± 46 mg.100 g−1 protein; lactulose = 1997 ± 658/409 ± 161 mg.L−1), whereas the so-called heat-treated samples (n = 9) had a heat load in between showing an extreme range of variation for both TTIs.

No MeSH data available.


Related in: MedlinePlus

Native polyacrylamide gel electrophoresis (12.5% T) of whey protein fractions soluble at pH 4.6 of different dairy products. a Whipping cream samples (group I, left side): pasteurized, ESL, and UHT samples; b selected coffee cream/milk and condensed (cond.) milk samples (group II, right side): “heat treated”, UHT, and sterilized samples. Raw milk and pasteurized milk are given as references. BSA (bovine serum albumin), α-lactalbumin (α-La), and β-lactoglobulin (β-Lg) as well as β-Lg concentrations as determined with RP-HPLC in milligrams per liter (if concentration was under LOQ–n.d. not determined)
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Fig4: Native polyacrylamide gel electrophoresis (12.5% T) of whey protein fractions soluble at pH 4.6 of different dairy products. a Whipping cream samples (group I, left side): pasteurized, ESL, and UHT samples; b selected coffee cream/milk and condensed (cond.) milk samples (group II, right side): “heat treated”, UHT, and sterilized samples. Raw milk and pasteurized milk are given as references. BSA (bovine serum albumin), α-lactalbumin (α-La), and β-lactoglobulin (β-Lg) as well as β-Lg concentrations as determined with RP-HPLC in milligrams per liter (if concentration was under LOQ–n.d. not determined)

Mentions: Selected whipping cream, coffee cream/milk, and condensed milk samples of different heating categories (pasteurized, “heat treated”, ESL, UHT, sterilized) were applied to native PAGE (12.5% T). Acid-soluble whey proteins were separated, and the results of both groups are shown in Fig. 4a and b, where raw milk and pasteurized milk are given as references. Protein patterns of raw milk (Fig. 4a) and pasteurized liquid milk (Fig. 4b) showed intense bands of typical whey protein fractions (e.g., α-La, bovine serum albumin (BSA) and β-Lg), whereas banding patterns of whipping cream samples were weaker (especially β-Lg), thereby showing distinct differences in intensity comparing the different heating categories (Fig. 4a). Obviously, intensity of acid-soluble whey proteins decreased corresponding to an increasing heat load of whipping cream samples analyzed. Thus, pasteurized and ESL whipping cream could be clearly differentiated from UHT whipping cream samples; corresponding β-Lg concentrations measured by RP-HPLC are given on top of the electrophoretogram (Fig. 4a).Fig. 4


Analytical assessment of the intense heat load of whipping cream, coffee cream, and condensed milk at retail in Austria and Germany
Native polyacrylamide gel electrophoresis (12.5% T) of whey protein fractions soluble at pH 4.6 of different dairy products. a Whipping cream samples (group I, left side): pasteurized, ESL, and UHT samples; b selected coffee cream/milk and condensed (cond.) milk samples (group II, right side): “heat treated”, UHT, and sterilized samples. Raw milk and pasteurized milk are given as references. BSA (bovine serum albumin), α-lactalbumin (α-La), and β-lactoglobulin (β-Lg) as well as β-Lg concentrations as determined with RP-HPLC in milligrams per liter (if concentration was under LOQ–n.d. not determined)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC5037155&req=5

Fig4: Native polyacrylamide gel electrophoresis (12.5% T) of whey protein fractions soluble at pH 4.6 of different dairy products. a Whipping cream samples (group I, left side): pasteurized, ESL, and UHT samples; b selected coffee cream/milk and condensed (cond.) milk samples (group II, right side): “heat treated”, UHT, and sterilized samples. Raw milk and pasteurized milk are given as references. BSA (bovine serum albumin), α-lactalbumin (α-La), and β-lactoglobulin (β-Lg) as well as β-Lg concentrations as determined with RP-HPLC in milligrams per liter (if concentration was under LOQ–n.d. not determined)
Mentions: Selected whipping cream, coffee cream/milk, and condensed milk samples of different heating categories (pasteurized, “heat treated”, ESL, UHT, sterilized) were applied to native PAGE (12.5% T). Acid-soluble whey proteins were separated, and the results of both groups are shown in Fig. 4a and b, where raw milk and pasteurized milk are given as references. Protein patterns of raw milk (Fig. 4a) and pasteurized liquid milk (Fig. 4b) showed intense bands of typical whey protein fractions (e.g., α-La, bovine serum albumin (BSA) and β-Lg), whereas banding patterns of whipping cream samples were weaker (especially β-Lg), thereby showing distinct differences in intensity comparing the different heating categories (Fig. 4a). Obviously, intensity of acid-soluble whey proteins decreased corresponding to an increasing heat load of whipping cream samples analyzed. Thus, pasteurized and ESL whipping cream could be clearly differentiated from UHT whipping cream samples; corresponding β-Lg concentrations measured by RP-HPLC are given on top of the electrophoretogram (Fig. 4a).Fig. 4

View Article: PubMed Central - PubMed

ABSTRACT

Time temperature integrators (TTIs) are useful tools in estimating the heat load applied on differently processed dairy products. The objective of this study was to analyze and assess three TTIs – lactulose, furosine, and acid-soluble β-lactoglobulin (β-Lg) – in 70 high heated dairy products at retail in Austria and Germany comprising whipping cream, coffee cream/milk, and condensed milk products. While β-Lg was not appropriate to evaluate the heat load of these products, furosine and especially lactulose increased with rising intensity of heat treatment, and are appropriate to distinguish between several heating categories analyzed. Pasteurized (n = 8) and “heat treated” (n = 5) whipping cream samples showed lowest furosine (48 ± 14/ 45 ± 19 mg.100 g−1 protein) and low lactulose (29 ± 10/57 ± 28 mg.L−1) concentrations, followed by ESL whipping cream (n = 10), ESL coffee cream (n = 1), and UHT whipping cream (n = 10) (furosine = 72 ± 37/71/161 ± 30 mg.100 g−1 protein; lactulose = 56 ± 41/161/195 ± 39 mg.L−1), respectively. Sterilized condensed milk samples (n = 14) showed the highest concentrations of both TTIs and could be clearly separated from UHT treated samples (n = 5) (furosine = 491 ± 196/216 ± 46 mg.100 g−1 protein; lactulose = 1997 ± 658/409 ± 161 mg.L−1), whereas the so-called heat-treated samples (n = 9) had a heat load in between showing an extreme range of variation for both TTIs.

No MeSH data available.


Related in: MedlinePlus