Improvement of rheological properties of firm acid gels by skim milk heating is conserved after stirring

2003 ◽  
Vol 70 (4) ◽  
pp. 423-431 ◽  
Author(s):  
P Cayot ◽  
J-F Fairise ◽  
B Colas ◽  
D Lorient ◽  
G Brulé
Keyword(s):  
Storage Modulus ◽  
Skim Milk ◽  
Rheological Parameters ◽  
Water Retention Capacity ◽  
Gel Structure ◽  
Casein Micelles ◽  
Retention Capacity ◽  
Β Lactoglobulin

The enhancement of the strength of set acid gels by heating milk was related to rheological parameters (water retention capacity, storage modulus) of corresponding stirred gels. To obtain accurate rheological data from stirred gel it was necessary to maintain a constant granulometry of gel particles and to recognize time after stirring as a contributing factor. Two hours after stirring, the gel exhibited a higher storage modulus when milk was heated above 80 °C. A measurement of viscosity of just-stirred yoghurt was sufficient to predict correctly the quality of a stirred gel analysed by viscoelastic measurements. Increased resstance to syneresis of just-stirred gels was related to higher viscosity. The quantity of β-lactoglobulin (β-lg) bound to casein micelles explains the improvement of these gel qualities. We have considered that the structure of the initial firm gel (mesostructure level) was conserved in fragments within the stirred gel. Consequently, the explanation given by various authors for the effect of heating milk on the properties of set gels can also be applied to stirred gels. The same mechanism, described in literature for structure formation of set gels from acidified milk is purposed to explain the role of heating milk on the recovery of gel structure after stirring. The β-lg association with casein micelles during heating favoured micelle connections during the acidification. It also favoured the association of gel fragments after stirring during the recovery in gel structure.

The Role of β-lactoglobulin in the primary phase of rennin action on heated casein micelles and heated milk

1974 ◽  
Vol 41 (3) ◽  
pp. 367-372 ◽  
Author(s):  
J. V. Wheelock ◽  
A. Kirk
Keyword(s):  
Heat Treatment ◽  
Complex Formation ◽  
Skim Milk ◽  
Primary Phase ◽  
Casein Micelles ◽  
Heated Milk ◽  
Β Lactoglobulin

SummaryIt has been shown that the inhibition caused by heat treatment, of the primary phase of rennin action on casein micelles, is dependent on the presence of β-lactoglobulin. The degree of inhibition increased with increasing amounts of added β-lactoglobulin for both heated casein micelles and heated skim-milk to a constant value. The results are fully consistent with the hypothesis that the inhibition is caused by complex formation between β-lactoglobulin and κ-casein when milk is heated.

scholarly journals Role of Growing Medium in Yield and Quality of Anthurium: A Review

2019 ◽  
Vol 40 (03) ◽  
Author(s):  
Paramveer Singh ◽  
Arti Arhar ◽  
Ajay Bhardwaj
Keyword(s):  
Flowering Plant ◽  
Water Retention Capacity ◽  
Flower Stalk ◽  
Retention Capacity ◽  
Yield And Quality ◽  
Growing Medium ◽  
Aerial Roots ◽  
Good Medium

Anthurium belongs to family Araceae and is highly praised flowering plant for its colourful long lasting unique flower and shining foliage. It is also an excellent plant for interior and as cut flower, especially for flower arrangement. The most suitable part of anthurium is modification of the leaf and botanically known as ‘spathe’. Heart shaped spathe emerges on the long flower stalk with a spadix. This plant blooms almost continuously under suitable conditions. It is epiphytic in nature with climbing, creeping and arboreous stems including many aerial roots that aid in taping water and nourishment. Quality and productivity of anthurium flowers depends on the growing medium. Most of the anthurium growers prepare own their growing media, but they do not know that the low productivity and quality might come from an poor potting mixture that they are using. One of the most important components of anthurium cultivation is the choice of growing substrate or medium. It is known to grow best in a well aerated medium with good water retention capacity and drainage. A good medium needs to be able to anchor the roots and stems so that the plant will not topple over as it grows larger, yet it should provide sufficient moisture, nutrient and aeration to the plant. The objective of this review is to present a summary of the influence of various growing medium on the growth, flowering, productivity and quality of anthurium grown in protected conditions. The results from the literature prove that the productivity of anthurium tends to be more in those plants which grown in different growing medium compared to soil grown plants.

Effect of Storage Time on the Physicochemical and Sensory Properties of Man-tou (Chinese Steamed Bread)

2007 ◽  
Vol 3 (3) ◽  
Author(s):  
Kun Sha ◽  
Ping Qian ◽  
Li-Jun Wang ◽  
Zhan-hui Lu ◽  
Li-Te Li
Keyword(s):  
Water Retention ◽  
Storage Time ◽  
Soluble Starch ◽  
Prolonged Storage ◽  
Water Retention Capacity ◽  
Study Quality ◽  
Total Water ◽  
Retention Capacity ◽  
Steamed Bread

In this study, quality of Man-tou, the Chinese traditional steamed bread during storage was studied. Values for water retention capacity, total water solubles, soluble starch, and soluble amylose and amylopectin of Man-tou decreased with storage time. Results showed that hardness, chewiness and gumminess of Man-tou increased, while, springiness cohesiveness and resilience decreased along with prolonged storage time (p<0.05). Sensory evaluation results showed that all sensory rating of Man-tou, including softness, stickiness, cohesiveness, elasticity, taste and total score, dropped drastically within 24 h of storage time (p<0.05). Differential Scanning Calorimeter (DSC) was used to determine crystalline structure of amylopectin in Man-tou, and the value for enthalpy of crystallization was found increased with storage time. Amylopectin crystallization was significantly associated to Man-tou firming (p<0.01).

Ethanol stability of casein micelles – a hypothesis concerning the role of calcium phosphate

1987 ◽  
Vol 54 (3) ◽  
pp. 389-395 ◽  
Author(s):  
David S. Horne
Keyword(s):  
Ionic Strength ◽  
Skim Milk ◽  
Buffer System ◽  
Casein Micelles ◽  
Buffer Solutions ◽  
Relative Response ◽  
Using Data ◽  
The Stability ◽  
Ethanol Stability

SummaryThe ethanol (EtOH) stability of skim milk and the stability towards aggregation of casein micelles diluted into ethanolic buffer solutions were compared using data obtained from previously published experiments. Differences in absolute stability and in relative response were observed when Ca2+ level and pH were adjusted, the buffer system results lying below those from skim milk in both cases. Increasing the ionic strength of skim milk adjusted to pH 7·0 lowered its EtOH stability whereas increasing the ionic strength of the diluting buffer increased the stability of the casein micelles. The hypothesis is put forward that the differences are due to the simultaneous precipitation of Ca phosphate when EtOH is added to skim milk. This draws calcium from the caseinate sites of the micelle, counteracting the destabilizing effects of the EtOH towards the micelle. Such removal and the consequent restructuring are kinetically controlled and micellar precipitation in skim milk finally occurs when the micellar coagulation time falls within the time scale of the restructuring reactions.

High-pressure treatment of milk: effects on casein micelle structure and on enzymic coagulation

2000 ◽  
Vol 67 (1) ◽  
pp. 31-42 ◽  
Author(s):  
ERIC C. NEEDS ◽  
ROBERT A. STENNING ◽  
ALISON L. GILL ◽  
VICTORIA FERRAGUT ◽  
GILLIAN T. RICH
Keyword(s):  
Whey Proteins ◽  
Skim Milk ◽  
Casein Micelle ◽  
Casein Micelles ◽  
Dense Networks ◽  
Protein Levels ◽  
Micelle Structure ◽  
Milk Casein ◽  
Β Lactoglobulin ◽  
Gel Network

High isostatic pressures up to 600 MPa were applied to samples of skim milk before addition of rennet and preparation of cheese curds. Electron microscopy revealed the structure of rennet gels produced from pressure-treated milks. These contained dense networks of fine strands, which were continuous over much bigger distances than in gels produced from untreated milk, where the strands were coarser with large interstitial spaces. Alterations in gel network structure gave rise to differences in rheology with much higher values for the storage moduli in the pressure-treated milk gels. The rate of gel formation and the water retention within the gel matrix were also affected by the processing of the milk. Casein micelles were disrupted by pressure and disruption appeared to be complete at treatments of 400 MPa and above. Whey proteins, particularly β-lactoglobulin, were progressively denatured as increasing pressure was applied, and the denatured β-lactoglobulin was incorporated into the rennet gels. Pressure-treated micelles were coagulated rapidly by rennet, but the presence of denatured β-lactoglobulin interfered with the secondary aggregation phase and reduced the overall rate of coagulation. Syneresis from the curds was significantly reduced following treatment of the milk at 600 MPa, probably owing to the effects of a finer gel network and increased inclusion of whey protein. Levels of syneresis were more similar to control samples when the milk was treated at 400 MPa or less.

Effects of High Hydrostatic Pressure Treated Mung Bean Starch on Characteristics of Batters and Crusts from Deep-Fried Pork Nuggets

2014 ◽  
Vol 10 (2) ◽  
pp. 261-268 ◽  
Author(s):  
Lingwen Zhang ◽  
Hongfang Ji ◽  
Mingduo Yang ◽  
Hanjun Ma
Keyword(s):  
Hydrostatic Pressure ◽  
High Hydrostatic Pressure ◽  
Mung Bean ◽  
Oil Content ◽  
Dry Weight ◽  
Water Retention Capacity ◽  
Starch Granules ◽  
Retention Capacity ◽  
Mung Bean Starch

Abstract Influences of mung bean starches treated with different high hydrostatic pressure (HHP) on the properties of batters and crusts from deep-fried pork nuggets were explored. HHP-treated starch increased water retention capacity of batter and consequently the batter pick-up. The increase in pressure at 150–450 MPa could facilitate hydration and swelling of starch granules during gelatinization. The crusts containing HHP-treated starches had higher moisture and less oil content, and the oil content was 15.82 g/100 g dry weight (DW) for 450 MPa treated starch, which was much lower than that of native starch (18.39 g/100 g DW) (p<0.05). Additionally, HHP-treated starches changed the crispness of crusts with increases in the slope and decrease in the shearing distance. Results indicated that mung bean starch treated with HHP in the range of 150–450 MPa could improve the quality of deep-fried battered food.

Comparison of heat and pressure treatments of skim milk, fortified with whey protein concentrate, for set yogurt preparation: effects on milk proteins and gel structure

2000 ◽  
Vol 67 (3) ◽  
pp. 329-348 ◽  
Author(s):  
ERIC C. NEEDS ◽  
MARTA CAPELLAS ◽  
A. PATRICIA BLAND ◽  
PRETIMA MANOJ ◽  
DOUGLAS MACDOUGAL ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Whey Protein ◽  
Skim Milk ◽  
Milk Proteins ◽  
Whey Protein Concentrate ◽  
Protein Concentrate ◽  
Casein Micelles ◽  
Micelle Structure ◽  
Dynamic Structures ◽  
Β Lactoglobulin

Heat (85 °C for 20 min) and pressure (600 MPa for 15 min) treatments were applied to skim milk fortified by addition of whey protein concentrate. Both treatments caused > 90% denaturation of β-lactoglobulin. During heat treatment this denaturation took place in the presence of intact casein micelles; during pressure treatment it occurred while the micelles were in a highly dissociated state. As a result micelle structure and the distribution of β-lactoglobulin were different in the two milks. Electron microscopy and immunolabelling techniques were used to examine the milks after processing and during their transition to yogurt gels. The disruption of micelles by high pressure caused a significant change in the appearance of the milk which was quantified by measurement of the colour values L*, a* and b*. Heat treatment also affected these characteristics. Casein micelles are dynamic structures, influenced by changes to their environment. This was clearly demonstrated by the transition from the clusters of small irregularly shaped micelle fragments present in cold pressure-treated milk to round, separate and compact micelles formed on warming the milk to 43 °C. The effect of this transition was observed as significant changes in the colour indicators. During yogurt gel formation, further changes in micelle structure, occurring in both pressure and heat-treated samples, resulted in a convergence of colour values. However, the microstructure of the gels and their rheological properties were very different. Pressure-treated milk yogurt had a much higher storage modulus but yielded more readily to large deformation than the heated milk yogurt. These changes in micelle structure during processing and yogurt preparation are discussed in terms of a recently published micelle model.

scholarly journals Production of kale seedlings on substrates containing proportions of organic compost

2021 ◽  
Vol 10 (8) ◽  
pp. e58010817707
Author(s):  
José Luís Trevizan Chiomento ◽  
Isabel Cristina Lourenço da Silva ◽  
Lourival Dantas Fagundes ◽  
Rafael Tronco Homrich ◽  
Nicolas dos Santos Trentin ◽  
...  
Keyword(s):  
Root System ◽  
Aerial Part ◽  
Water Retention ◽  
Chemical Characterization ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
The One ◽  
Physical And Chemical ◽  
Organic Compost

One of the difficulties in the kale seedlings production in containers is to ensure the production of aboveground biomass with a limited portion of roots, restricted to a small volume of substrate. Thus, we investigated whether substrates with organic compost added to it associated with kale cultivars interfere in the quality of seedlings produced in a greenhouse. Here, we studied two kale cultivars and five substrates. The experiment was designed in randomized blocks, with treatments arranged in a bifactorial scheme (2 x 5), with three replications. We carried out the physical and chemical characterization of the substrates and evaluated attributes of the aerial part and root system of the kale seedlings. The results showed that the substrate with the highest water retention was the one without the addition of organic compost. The greater the proportion of organic compound added to the substrate, the higher the nitrogen, phosphorus and organic carbon values. Seedlings produced in the substrate with greater water retention capacity had better performance in relation to the morphology of the aerial part and the morphology of the root system. We conclude that seedlings of kale cultivars associated with substrates with higher water retention have better quality. Seedlings of the ‘Gaudina’ cultivar stand out for their better phytometric morphology, while seedlings of the ‘Manteiga’ cultivar have higher quality of root biomass.

scholarly journals Use of organic fertilization with irrigation in coffee production in brazilian cerrado

2020 ◽  
Vol 15 (5) ◽  
pp. 1
Author(s):  
André Luís Teixeira Fernandes ◽  
Eusímio Felisbino Fraga Júnior ◽  
Márcio José de Santana ◽  
Reginaldo De Oliveira Silva ◽  
Marcelo Moreira Dias
Keyword(s):  
Water Retention ◽  
Chicken Manure ◽  
Water Retention Capacity ◽  
Brazilian Cerrado ◽  
Soil Water Retention ◽  
Organic Fertilization ◽  
Retention Capacity ◽  
Yield And Quality ◽  
Productive Development

Coffee irrigation has increased in the main Brazilian coffee regions. However, in recent years, with climate change, years with water deficits greater than 150 mm have been observed, affecting the vegetative and productive development of the crop and also the replenishment of surface and underground springs. One practice that increases soil water retention capacity is organic fertilization. This work evaluated different combinations of irrigation and organic fertilization on the yield and quality of coffee produced in the Minas Gerais cerrado region. The treatments were: T1: total irrigation; T2: no irrigation; T3: total irrigation + organic fertilization (chicken manure, 10 ton ha-1); T4: no irrigation + organic fertilization (chicken manure, 10 ton ha-1); T5: 50% irrigation + organic fertilization (chicken manure, 10 ton ha-1). After 7 harvests, it was concluded that the treatment that combined organic fertilization with application of half of the necessary irrigation presented the best yield, superior to the treatment with total irrigation and exclusively mineral nutrition.

Effect of biochar amendment on the properties of growing media and growth of containerized Norway spruce, Scots pine, and silver birch seedlings

2021 ◽  
Vol 51 (1) ◽  
pp. 31-40
Author(s):  
Egle Köster ◽  
Jukka Pumpanen ◽  
Marjo Palviainen ◽  
Xuan Zhou ◽  
Kajar Köster
Keyword(s):  
Norway Spruce ◽  
Scots Pine ◽  
Silver Birch ◽  
Water Retention Capacity ◽  
Retention Capacity ◽  
Growing Media ◽  
Collar Diameter ◽  
Aboveground Growth ◽  
Biochar Amendment

Common practices and several studies have demonstrated the positive effect of biochar amendment on climate change mitigation, soil properties, and plant growth. We performed a greenhouse experiment to assess the potential of wood biochar to improve the properties of the growing media and the growth of seedlings in boreal tree species. We added willow biochar (0%, 5%, 10%, and 20%) to raw peat and measured the growth of Norway spruce (Picea abies (L.) H. Karst.), Scots pine (Pinus sylvestris L.), and silver birch (Betula pendula Roth) seedlings. In addition, the co-effect of biochar amendment with 0%, 50%, and 100% fertilization was estimated. We found that using up to 10% of biochar did not reduce the water retention capacity of the growing media significantly. Moreover, biochar amendment significantly increased carbon, nitrogen, potassium, and phosphorus concentrations and had a significant liming effect on the growing media. The biochar amendment increased the aboveground growth of spruce seedlings and root biomass, as well as the root collar diameter, of birch seedlings. Biochar amendment did not affect the quality of seedlings, estimated by the Dickson’s quality index, for spruce and pine, while the quality of birch increased. Based on our results, biochar has potential in forest seedling production.

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