Whey Powder (whey + powder)

Distribution by Scientific Domains


Selected Abstracts


Antioxidative ability of native and thermized sour whey in oxidation-catalysed model systems,

INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2007
JINHAN SHON
Antioxidative properties of sour (cottage) were evaluated with (thermized) and without (native) heat treatment (80°C for 30 min). A model system comprising a Tween 20 stabilized peanut oil in phosphate buffer (pH 7.0) emulsion containing lipid oxidation catalysts, FeCl3, H2O2 and ascorbate was used. Native sour whey powder (SWP) was significantly better than thermized whey in terms of limiting the formation of thiobarbituric acid-reactive substances and peroxide value. Antioxidative ability was best at pH 3.0 and decreased with increasing pH. SWP (20%, w/v) was significantly better than all commonly used antioxidants tested after 96 h of incubation at 40°C. [source]


EFFICACY OF SOUR WHEY AS A SHELF-LIFE ENHANCER: USE IN ANTIOXIDATIVE EDIBLE COATINGS OF CUT VEGETABLES AND FRUIT,

JOURNAL OF FOOD QUALITY, Issue 5 2007
JINHAN SHON
ABSTRACT The effectiveness of edible coatings containing sour whey powder (SWP), compared with soy protein isolate (SPI) and calcium caseinate (CC), in reducing oxidative browning and moisture loss during storage (4C) of cut apples, potatoes, carrots, and onions was investigated. Oxidative discoloration, as determined by the Commission Internationale de I'Eclairage L*a*b* color scale, was significantly reduced (P < 0.05) by treatments over a storage time of 120 min. Loss of lightness was reduced by CC, SPI and SWP coatings. These respectively showed 2.7, 3.3 and 1.5% change of L* value in coated apples as compared with 7.4% in the control. Browning in cut potatoes was significantly reduced from a 145.1% increase in the a* value of the control to 45.9, 37.0 and 30.3% increase for CC, SPI and SWP treatments, respectively. The b* values also reflected the effectiveness of SWP. The moisture barrier effect, tested over a period of 5 days at 4C, was significantly better for the treatments than control. SWP was the best and significantly reduced moisture loss in potatoes and carrots by 40 and 59%, respectively, over control. Cut onions did not show any treatment effect both in terms of off-color development and moisture loss. The reasons for the excellent moisture barrier and antioxidative property of SWP were discussed. PRACTICAL APPLICATIONS Oxidative degradation of fresh fruits and vegetables is a major problem faced by the industry today. Most of the fresh produce is grown in the southwestern part of the country, requiring days of transportation to retail outlets. As the educated consumer is highly health conscious, any effort in extending the shelf life will have to be nonchemical, and preferably natural. Because of small profit margins, the intervention must also be inexpensive. Millions of MT of sour whey, a by-product of cottage whey manufacture, is wasted because of the lack of appropriate food applications. It is natural, nutritious and presently very inexpensive. Our research investigated the possibility of using this by-product as a final wash to enhance the so-called window of freshness of fresh produce and fruit. [source]


Color Stability of Edible Coatings During Prolonged Storage

JOURNAL OF FOOD SCIENCE, Issue 7 2000
T.A. Trezza
ABSTRACT: The yellowing rates of edible coatings were determined at 23, 40, and 55 °C at 75% relative humidity (RH). Whey protein isolate (WPI) coatings had lower yellowing rates than whey protein concentrate (WPC) and the same rates as shellac coatings. Hydroxypropyl methylcellulose (HPMC) coatings had the lowest yellowing rates. Zein coatings became less yellow during storage; however, their color was still pronounced. Activation energies and Q10 values for the yellowing of whey protein coatings were similar to those previously reported for the browning of whey powder. The results indicate that WPI coatings can be used in place of shellac coatings when low-color development is desired. WPC coatings can be used to tailor color development of a food. [source]


PHYSICAL, SENSORY AND FLOW PROPERTIES OF WHEAT STARCH,DAIRY BY-PRODUCT SPRAY-DRIED PEKMEZ MIXTURES

JOURNAL OF TEXTURE STUDIES, Issue 2 2008
DURMU
ABSTRACT Pekmez, also known as a concentrated grape juice, was spray dried in a laboratory-type pilot drying unit to obtain pekmez powder (PP). The flow characteristics of PP, wheat starch (WS) and some dairy by-products (whey powder, skim milk powder, calcium caseinate and sodium caseinate) systems as binary and ternary mixtures were studied. The empirical power law model fitted the apparent viscosity,rotational speed data. PP,dairy by-product and WS,dairy by-product mixed solutions exhibited a shear-thinning behavior at 21C with flow behavior index (n) values of 0.86 , n , 0.92 and 0.06 , n , 0.27, respectively. WS,dairy by-product mixed solutions showed high shear-thinning behavior with the highest consistency index (k = 25,425,180,599 mPa·sn). However, PP,WS and PP,WS,dairy by-product mixed solutions at the same temperature exhibited the shear-thickening behavior with flow behavior index (n) values of 1.05 , n , 1.18. PRACTICAL APPLICATIONS Pekmez has become popular as a healthy food product; therefore, its rheologic properties were extensively studied by some researchers. However, pekmez powder (PP) is a new product and has not been produced yet in the food industry. Spray drying of foods has been spread recently in almost all food industry branches because it provides some advantages such as extending the shelf life, storage stability, decreasing the storage costs of the food products, etc. For this reason, production technology is first developed; PP is produced and studied in this study. There is no published data informing the rheologic, physical and sensory properties of pekmez or PP as binary and ternary mixtures with other components such as wheat starch (WS) and any dairy by-product. The purpose of this study was mainly to characterize the rheologic behavior of the PP,WS,dairy by-product mixed solutions and determine their physical and sensory properties. [source]


An evaluation of biological and abiotic controls for grapevine powdery mildew.

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2006

Abstract Grapevine powdery mildew (Erysiphe necator) affects grape yield and fruit quality worldwide. Managers of conventional vineyards rely mainly on synthetic fungicides and sulfur to control powdery mildew, while in organic vineyards sulfur is the main control agent, often in rotation with canola-based oils, bicarbonates and biological control agents. The efficacy of those materials has not been evaluated critically under field conditions in Australia. Accordingly, a range of materials showing most promise in previous greenhouse trials (Crisp et al. 2006 Australian Journal of Grape and Wine Research12, pp. 192,202) were assessed via field trials in commercial vineyards. Applications of either milk or whey (alone, or mixed with a canola oil-based product), as well as applications of potassium bicarbonate (commercial formulation), all reduced the severity of powdery mildew compared with untreated vines. Eight applications of a 1:10 dilution of milk, 45 g/L whey powder or programs comprising rotations of potassium bicarbonate plus oil and whey, applied at 10,14 day intervals, reduced the severity of powdery mildew to levels not significantly different from that on vines sprayed with sulfur (wettable powder, 3,6 g/L). However, the relative control of powdery mildew by the test materials in field trials was dependent on the susceptibility of the grapevine cultivar and the extent of spray coverage achieved. In vineyards where highly susceptible cultivars were planted, and spray coverage was compromised, the resultant control of powdery mildew was reduced; and sometimes to commercially unacceptable levels. [source]