Food Gels (food + gel)

Distribution by Scientific Domains


Selected Abstracts


CHARACTERISTICS OF GELLAN GUM BASED FOOD GELS

JOURNAL OF TEXTURE STUDIES, Issue 4 2010
DIPJYOTI SAHA
ABSTRACT Fruit-based gels with gellan gum as the gelling agent was prepared. Textural attributes of the gellan gum gels, formed with different concentrations of the gum (0.5,3.0%) and sugar and/or pineapple juice, were determined employing the methods of large-deformation uniaxial compression and stress relaxation. Fracture stress/energy markedly increases with an increase in the concentration of gellan gum while fracture strain exhibits a marginal effect. The change in these compressive textural parameters is more pronounced for sugar added samples compared with gels without sugar. Marked decay in stress relaxation curves was observed; the extent of relaxation decreases marginally with an increase in gum content up to 2% but shows much lesser values beyond 2% addition. The sugar added samples exhibit lesser relaxation characteristics but higher relaxation times indicating elastic characteristics compared with samples without sugar. Use of gellan gum provides an innovative method for developing fruit juice based gels as a convenience food because of attractive transparent appearance and textural attributes. PRACTICAL APPLICATION The use of hydrocolloids like gellan gum can develop fabricated foods in the form of fruit juice based gels having unique textural properties. These properties can be altered to suit the consumer preference by varying the proportions of gellan gum, fruit juice and sugar. The results in the present investigation arising from compression and relaxation testing thus help in characterizing the developed gels. [source]


Relaxation Time Spectrum of Hydrogels by CONTIN Analysis

JOURNAL OF FOOD SCIENCE, Issue 3 2000
R. Mao
ABSTRACT: CONTIN is a general-purpose program for inverting noisy linear algebraic and integral equations by means of inverse Laplace transform. This study explored the application of CONTIN analysis to determine the relaxation time distribution spectra for food gels, including gellan, carrageenan, whey protein, and gelatin gels, based on stress-relaxation data. CONTIN results represent the continuous relaxation time spectra when the number of the terms in the discrete Maxwell stress-relaxation model approached infinity. The CONTIN results for gellan gels were correlated to the texture properties of gels from compression tests with respect to the effects of calcium concentrations. CONTIN analysis may be a very effective tool in elucidating the microstructural properties of a hydrogel from mechanical testing. [source]


GELLING BEHAVIOR OF RICE FLOUR DISPERSIONS AT DIFFERENT CONCENTRATIONS OF SOLIDS AND TIME OF HEATING

JOURNAL OF TEXTURE STUDIES, Issue 3 2008
ALKA KAPRI
ABSTRACT Rice flour dispersions, under suitable conditions of processing, can form a gel. The effect of concentration of solids (10,18%) and time (0,75 min) of processing on textural attributes, and viscoelasticity were investigated along with sensory attributes. The textural attribute determined is gel strength, while viscoelasticity was determined in terms of mechanical spectra like storage modulus (G,), loss modulus (G,), complex viscosity (,*) and loss factor (tan ,) during a frequency sweep varying from 0.01 to 40 Hz at a constant stress of 25 Pa. Microstructural observation indicates the swelling of starch granules in the beginning of heating, while damaged granule and leached-out materials are visible at the end of the gelling process. Desirability function analysis has been applied to obtain a rice gel with acceptable textural attributes; a solid concentration of 15.2% and a heating time of 75 min can lead to the development of a gel with a satisfaction level of 0.6. PRACTICAL APPLICATIONS Rice flour gels in the form of hard-set gels, porridges and spreads are popular in several parts of the world particularly for feeding of infants and children. The application of the present study lies in understanding the role of major processing variables on the quality attributes and viscoelasticity of a product, characterization of cooked gels and for developing rice flour-based food gels. The findings may also be extended for the development of other cereal-based gels. [source]


Ferulic acid: pharmaceutical functions, preparation and applications in foods

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2004
Shiyi Ou
Abstract Ferulic acid (4-hydroxy-3-methoxycinnamic acid), an effective component of Chinese medicine herbs such as Angelica sinensis, Cimicifuga heracleifolia and Lignsticum chuangxiong, is a ubiquitous phenolic acid in the plant kingdom. It is mainly conjugated with mono- and oligosaccharides, polyamines, lipids and polysaccharides and seldom occurs in a free state in plants. Ferulic acid is a phenolic acid of low toxicity; it can be absorbed and easily metabolized in the human body. Ferulic acid has been reported to have many physiological functions, including antioxidant, antimicrobial, anti-inflammatory, anti-thrombosis, and anti-cancer activities. It also protects against coronary disease, lowers cholesterol and increases sperm viability. Because of these properties and its low toxicity, ferulic acid is now widely used in the food and cosmetic industries. It is used as the raw material for the production of vanillin and preservatives, as a cross-linking agent for the preparation of food gels and edible films, and as an ingredient in sports foods and skin protection agents. Ferulic acid can be prepared by chemical synthesis and through biological transformation. As polysaccharide ferulate is a natural and abundant source of ferulic acid, preparation of ferulic acid from plant cell wall materials will be a prospective pathway. Copyright © 2004 Society of Chemical Industry [source]