Dairy products techniques

Conventional thermoforming of polystyrene and PVC is the most widely used technique for making packages for dairy products and for disposable cups and trays. 

In summary, the new 2D experiments of relaxation and diffusion appear to offer a new method to identify and quantify the components in dairy products. The two components are well separated in the 2D maps while they can be heavily overlapped in the ID spectrum. We find that some microscopic properties of the products can be reflected in the relaxation and diffusion properties. These new techniques are likely to be useful to assist the characterization of the products for quality control and quality assurance. 

Emey DR. 1975. Confirmation of polybrominated biphenyl residues in feeds and dairy products, using an ultraviolet irradiation-gas-liquid chromatographic technique. J Assoc Off Anal Chem 58(6) 1202-1205. 

TMP Cattaneo, A Feroldi, PM Toppino, C Olieman. Sample preparation for selective and sensitive detection of soya proteins in dairy products with chromatographic and electrophoretic techniques. Neth Milk Dairy J 48 225 -234, 1994. 

Fats, oils, and dairy products digest sample with lipase, extract with hexane. Purify hexane extracts obtained from either extraction technique by silica solid-phase extraction in the sample cleanup mode. The internal standard is phylloquinone 2,3-epoxide (unlabeled for UV detection and tritium labeled for coulometric detection). 

A simple isocratic technique was developed for the quantitative analysis of OAs in dairy products. An Aminex HPX-87 (300-mm X 7.8-mm ID) analytical column was eluted with 0.009 N H2S04 mobile phase UV detection at 220 and 275 nm was utilized. Lactic, citric, formic, acetic, propionic, and butyric acids were quantified for whole milk, skim milk powder,... 

Enhanced imaging of several dairy products has been demonstrated through the application of a relatively elaborate preparative technique in combination with a cold-field emission scanning electron microscope (FESEM) [86], The preparative methods include a metal-impregnation technique, termed tannin-ferrocyanide-osmium (TA-F-O, Figure 21), which was adapted from Hirano et al. [87]. 

Klotz,A. and Einspanier, R. (2001) Development of a DNA-based screening method to detect cow milkin ewe, goat and buffalo milk and dairy products using PCR-LCR-EIA technique. Milchwissenschaft, 56, 67-70. 

Gas chromatographic analysis of FFAs isolated from dairy products has been preformed by a number of different techniques. Examples of... 

Odor-active components in cheese flavor, many of which are derived from milk lipids, can be detected using GC-olfactometry (GC-O). GC-0 is defined as a collection of techniques that combine olfactometry, or the use of the human nose, as a detector to assess odor activity in a defined air stream post-separation using a GC (Friedich and Acree, 1988). The data generated by GC-0 are evaluated primarily by aroma extract dilution analysis or Charm analysis. Both involve evaluating the odor activity of individual compounds by sniffing the GC outlet of a series of dilutions of the original aroma extract and therefore both methods are based on the odor detection threshold of compounds. The key odourants in dairy products and in various types of cheese have been reviewed by Friedich and Acree (1988) and Curioni and Bosset (2002). 

Garcia-Ayuso, L.E., Luque De Castro, M.D. 1999. A comparative study between chromatography and other techniques for quantification of triglycerides and fatty acids in dairy products. Seminars Food Anal. 4, 39-52. 

Spectroscopic Techniques (NMR, Infrared and Fluorescence) for the Determination of Lipid Composition and Structure in Dairy Products... 

Spectroscopic Techniques Used to Study Fats in Dairy Products... 

Simple and rapid spectroscopic methods, such as front-face fluorescence, attenuated total reflectance Fourier-transform infrared and nuclear magnetic resonance spectroscopies, have a great potential for investigation of the structure of fats in dairy products and of the relation between structure and texture. Although fluorescence, infrared and NMR spectroscopies are techniques, the theory and methodology of which have been exploited extensively in studies in both chemistry and biochemistry, the usefulness of these spectroscopies for molecular studies has not been yet fully recognized in food science. Fluorescence, infrared and NMR spectroscopies coupled... 

From the general point of view, ultrasound has advantages regarding the measurement of dairy product quality in that it may be implemented inline, non-invasively and even using non-contacting techniques such as laser excitation and detection (Mulet et al, 1999). Ultrasound can also be safe, hygienic and economic in implementation, all characteristics desirable for any technique for the measurement of food quality (Povey, 1997a). Moreover, it can reveal aspects of the quality of dairy products which are not measurable by current techniques. An example is the extraordinary capability of ultrasound to detect crystal nucleation (Povey et al., 2001 Hindle et al., 2002). 

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