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Biochemical studies on some dairy products are supported by functional additives

Biochemical studies on some dairy products are supported by functional additives. By: Hesham Mohamed Ali. Introduction. Intorduction. Functions of Food. First function. Nutrition: supply of nutrients Organoleptic and/or Sociocultural properties Added value: health benefit. Food.

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Biochemical studies on some dairy products are supported by functional additives

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  1. Biochemical studies on some dairy products are supported by functional additives By: Hesham Mohamed Ali

  2. Introduction Intorduction

  3. Functions of Food • Firstfunction • Nutrition: supply of nutrients • Organoleptic and/or • Sociocultural properties • Added value: health benefit Food • Secondfunction Functional Food • Third function

  4. Functional foods, such as Probiotics: Living organisms which have additional positive influences on healthbesides their nutritive value, if they are eaten in sufficient amounts. Prebiotics: Fermentative substances, which have a positive influence on the microflora of the gut (for instance nutritional fiber, fructooligosaccharides). Sybiotics: Combination of pro- and prebiotic foods Designer Foods: Products which have been developed to meetspecial purposesasCLA.

  5. Producing Functional Foods Addition of one or more components Removal of one or more components Functional Food Food Modification of one or more components or its/their bioavailability Concentration of one or more components

  6. The idea of research

  7. Conjugated linoleic acid (CLA), an anticarcinogenic compound with numerous other health benefits, is present mainly in dairy and beef lipids The main .. CLA isomer present in dairy and beef lipids is cis 9, trans 11 CLA at a 0.5% concentration. The typical minimum human dietary intake of CLA is 10 times less than the 3 g/d.

  8. CLA Content of Sample Menu

  9. CLA content of various foods

  10. Chemical Structure of CLAs c9,t11 c11,t13 t11,c13 t10,c12 t7,c9 t10,t12 c11,c13

  11. linoleic acid conjugated linoleic acid D -6-desaturase g-linolenic acid conjugated linolenic acid elongase all-cis 8,11,14-eicosatrienoic acid conjugated eicosatrienoic acid D -5-desaturase arachidonic acid conjugated arachidonic acid eicosanoids lipoxygenase cyclooxygenase Prostaglandins Leukotrienes Thromboxane Formation of metabolites of C18:2 isomers

  12. Sources of CLA modified feeding (enrichment with peanut oil, sunflower oil, linseed oil) oil rich in linoleic acid (sunflower oil, soy oil, safflower oil) microbiological enrichment in butter Candida antarctica enrichment in milk factor 2 isomerization (base) enrichment factor 20 CLA mixture CLA isomers microbiological isomerase (immobilizing resp. transgene MO) chem. synthesis primary material, e.g. ricinoleic acid linoleic acid

  13. requirement that has been extrapolated from animal and cell-line studies. The objectives of this study were to produce CLA isomers from soybean oil by photoisomerization of soybean oil linoleic acid and to study the oxidation status of the oil. Refined, bleached, and deodorized soybean oil with added iodine concentrations of 0, 0.1, 0.25, and 0.5% was exposed to a 100-W mercury lamp for 0 to 120 h. An SP-2560 fused-silica capillary GC column with FID was used to analyze the esterified CLA isomers in the photoisomerized oil. The CLA content of the individual isomers was optimized by response surface methodology. Attenuated total reflectance (ATR)-FTIR spectra in the 3400 to 3600 cm−1 range and 1H NMR spectra in the 8 to 12 ppm range of the photoisomerized soybean oil were obtained to follow hydroperoxide formation. The largest amount of cis 9, trans 11 CLA isomer in soybean oil was 0.6%, obtained with 0.25% iodine and 84 h of photoisomerization. Lipid hydroperoxide peaks in the ATR-FTIR spectra and aldehyde peaks in the 1H NMR spectra were not observed in the photoisomerized soybean oil, and the spectra were similar to that of fresh soybean oil. This study shows that CLA isomers can be produced simply and inexpensively from soybean oil by photoisomerization.

  14. Photocatalytic Production and Processing of Conjugated Linoleic Acid-Rich Soy Oil • Daily intake of conjugated linoleic acid (CLA), an anticarcinogenic, antiatherosclerotic, antimutagenic agent, and antioxidant, from dairy and meat products is substantially less than estimated required values. The objective of this study was to obtain CLA-rich soybean oil by a customized photochemical reaction system with an iodine catalyst and evaluate the effect of processing on iodine and iodo compounds after adsorption. After 144 h of irradiation, a total CLA yield of 24% (w/w) total oil was obtained with 0.15% (w/w) iodine. Trans,trans isomers (17.5%) formed the majority of the total yield and are also associated with health benefits. The isomers cis-9,trans-11 and trans-10,cis-12 CLA, associated with maximum health benefits, formed approximately 3.5% of the total oil. This amount is quite significant considering that total CLA obtained from dairy sources is only 0.6%. ATR-FTIR, 1H NMR, and GC-MS analyses indicated the absence of peroxide and aldehyde protons, providing evidence that secondary lipid oxidation products were not formed during the photochemical reaction. Adsorption processing vastly reduced the iodine and iodocompounds without CLA loss. Photocatalysis significantly increased the levels of CLA in soybean oil.

  15. CLA content • Several factors influence the CLA content of food products, such as: • Temperature • Protein quality • Choice of starter cultures • Period of aging • Variations of CLA content in foods are also affected by the animal’s: • Diet (type of feed, feeding regimen, grass quality, dietary restriction) • Age or breed • Seasonal factors

  16. Health implications of CLA Influence of processing conditions: * aging/storage (e.g. time, temperature) * heat treatment (e.g. pasteurization or pan frying of meat) * fermentation conditions (e.g. starter cultures) * food additives (e.g. BHT, ascorbic acid, propyl gallate, sodium caseinate)

  17. Health implications of CLA • CLA has been shown to reduce body fat in mice, as well as in rats and chickens • Evaluation of the metabolic effects of CLA in both intact animals and in adiposity culture has suggested that CLA directly affects key enzymes and processes involved in lipid mobilization and storage

  18. Reference • DeLany JP, West DB. J American College of Nutrition, 19:4, 487S-493S (2000) • Rainer L, Heiss C. Conjugated Linoleic Acid: health implications and effects on body composition. 2004. JADA. 104:6. • Eynbard AR, Lopez CB. Lipids in Health and Disease 2:6, 2003.

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