Simplex-centroid mixture formulation for optimised composting of kitchen waste.

Composting is a good recycling method to fully utilise all the organic wastes present in kitchen waste due to its high nutritious matter within the waste. In this present study, the optimised mixture proportions of kitchen waste containing vegetable scraps (V), fish processing waste (F) and newspaper (N) or onion peels (O) were determined by applying the simplex-centroid mixture design method to achieve the desired initial moisture content and carbon-to-nitrogen (CN) ratio for effective composting process. The best mixture was at 48.5% V, 17.7% F and 33.7% N for blends with newspaper while for blends with onion peels, the mixture proportion was 44.0% V, 19.7% F and 36.2% O. The predicted responses from these mixture proportions fall in the acceptable limits of moisture content of 50% to 65% and CN ratio of 20-40 and were also validated experimentally

A Review on Analytical Methods for Honey Classification, Identification and Authentication

Authentication of food products is of great concern in the context of food safety and quality. In recent years, interest in honey authenticity in relation with botanical or geographical origin and adulteration has increased. Honey is a ready-to-eat natural food with high nutritional content and gives many health benefits. Authentication of honey has primary importance for both industries and consumers in combatting common honey frauds in the form of mislabeling of honey origin and adulteration with sugar or syrups. Various analytical methods are used for detecting original honey. With a diverse range of equipment and techniques, the conventional analytical methods are still being used in association with advanced techniques as they are part of preliminary screening, processing and product standards. Most of the analytical methods provide indications of pollen distribution, physicochemical parameters and profile analysis of phenolic, flavonoid, carbohydrate, amino acids, aroma and individual marker components. This review provides an overview and summary of instrumental and analytical methods available for honey authentication from conventional to recent molecular techniques. It is useful as a guide to choosing appropriate method for analysis, classification and authentication of honey

Glazing effects on bread crust and crumb staling during storage.

The uses of cornstarch, egg white, skim milk and shortening as glazes on bread surfaces were investigated for its ability to reduce bread staling. Four concentrations of glazes were applied to sweet bun surfaces. Bread crumb and crust samples were measured for its firmness and moisture during storage. The rates of change in firmness and moisture contents of crumb and crust with storage time were analyzed by comparing with nonglazed breads as control. While both crumb and crust firmness and the crust moisture content increased with storage time, crumb moisture content decreased significantly (P PRACTICAL APPLICATIONSThe use of glaze materials in baked products may provide more than an aesthetic function of creating appearance appeal. This research shows that glazing of breads reduces bread staling through its ability to retain crumb moisture and reduce crumb firming. This finding provides means of improving bread quality in terms of textural properties and its shelf life by means of processing and with no alter in ingredients' formulation

Rheological and textural studies of fresh and freeze-thawed native sago starche.

The viscoelastic and textural properties of freshly prepared and freeze-thawed sago starch–sugar gels were studied in comparison with other native starches from corn, wheat, tapioca, and potato. The gelatinisation and retrogradation properties of starches were studied using a DSC while the pasting properties of starch–sugar mixtures during the cooking period were studied using a starch pasting cell. The freeze-thaw stability of gels was evaluated by gravimetric measurements of the water of syneresis. The different starches gave properties which varied following to their botanical sources. High-amylose cereal starches (wheat and corn) produced harder gels, while low-amylose root starch (tapioca) produced softer gels. Sago and potato gels showed close similarities in their viscoelastic and textural characteristics. Although the freeze-thaw cycle greatly increased the viscoelasticity and hardness of these two gels, reheating at high temperature significantly reduced these negative effects and resulted in partial recovery of the gel structures. Sago starch produced gels with very low syneresis and high cohesiveness, implying its potential use as a gelling agent in the frozen food industries

Co-composting of palm oil mill wastes.

Co-composting is one of the important bio-waste treatments in the palm oil industry for achieving sustainable process and zero waste. However, improper conditions of composting may cause several problems such as gas emission, bad odour, low quality product, production delay and high handling cost. Enhancing the efficiency of waste composting becomes a vital issue to overcome these problems. This review provides information on the practices and developments related to co-composting of the palm oil mill waste. The description on a typical palm oil mill process and the wastes generated, i.e. empty fruit bunch and palm oil mill effluent, as composting substrates are given. The common windrow composting system is described. The recent venture of using microorganisms in composting processes are also covered under the pretext of several researchers’ interpretation that composting can be accelerated by the introduction of microorganism to the process through its influence on the physical, dynamic and biological behaviours of organic material. The criteria of choosing functional microbes for fast composting are discussed

Direct and indirect power ultrasound assisted pre-osmotic treatments in convective drying of guava slices

Application of ultrasound to osmotic dehydration of guava slices via indirect sonication using an ultrasonic bath system and direct sonication using an ultrasonic probe system was studied. Pre-treatments were designed in three osmotic solution concentrations of 0, 35, and 70 °Brix at indirect ultrasonic bath power from 0 to 2.5 kW for immersion times ranging for 20–60 min and direct ultrasonic probe amplitudes from 0 to 35% for immersion times of 6–20 min. The calculated ultrasound intensities from calorimetric ultrasound power dissipated indicated that direct sonication was more intensive than indirect sonication. The general linear model (GLM) showed that ultrasound input (power and amplitude), osmotic solution concentrations, and immersion time increased the water loss, solid gain, and total colour change of guava slices significantly with P < 0.0005. Indirect sonication in osmotic solutions contributed to high water loss and solid gain with acceptable total colour change than direct sonication. Applying ultrasound pre-osmotic treatment in 70 °Brix prior to hot-air drying reduced the drying time by 33%, increased the effective diffusivity by 35%, and decreased the total colour change by 38%. A remarkable decrease of hardness to 4.2 N obtained was also comparable to the fresh guava at 4.8 N

Development of nutraceutical product

The aim of this study was to discuss the development of nutraceutical product which includes the current market trends, challenges, and exploitation of natural resources through various processing. Wet granulation and dry granulation techniques were adopted for such processes. Wet granulation covers high shear mixing granulation, fluidized bed granulation, and twin screw granulation. Dry granulation covers roll compaction and uniaxial die compaction. These techniques were compared and reviewed in terms of physical, chemical and toxicity studies. The physical study considered the particle size, density, morphology, flowability and dissolution. The chemical study discussed on the active ingredients in the nutraceutical products and the toxicity study was presented by investigation carried out on rats. There is a high potential for development of nutraceutical product. By understanding the various techniques of processing and characterisations, more nutraceutical products can be marketed

Modelling of rheological behaviour of soursop juice concentrates using shear rate-temperature-concentration superposition

The effect of temperature and concentration on rheological behaviour of freeze dried soursop juice concentrates were investigated using a rheometer over a wide range of temperatures (10–70 °C) and concentrations (10–50 °Brix) at shear rates of 0–400 1/s. The Power law is the best fitted model to the rheological data due to the high value of coefficient of determination (R2 = 0.9989). The soursop juice concentrates exhibited shear thinning or pseudoplastic behaviour with n < 1. The consistency coefficients dependency on temperature and concentration were well described by Arrhenius relationship and exponential relationship respectively. The flow activation energy of soursop juice concentrates were 8.32–30.48 kJ/mol. The superposition technique with Power law model sufficiently modelled the overall rheological characteristics of soursop juice concentrates into a single master curve using shift factors based on double shifting steps with R2 = 0.9184. This technique also showed that the soursop juice concentrates increases in viscosity and pseudoplasticity behaviour with concentration

Effect of partial sugar replacement with ultrasonically treated citrus pectin on aeration and rheological properties of batter

Ultrasound treatment was applied on citrus pectin solution prior mixing into batter as partial replacement of sugar content. The pectin solutions were treated with ultrasound at 20%, 40%, and 60% amplitude for 5, 15, and 25 min. It was then replaced with 20% and 30% of sugar content in batter formulation. Aeration properties were tested by measuring batter density and rheological properties of batter, also volume and hardness of cake. The results shown that 20% of sugar replacement with non‐treated pectin in batter system gave lower batter density at lower viscosity, and higher consistency index with less viscoelasticity produced lower cake volume and cake hardness compared with 30% of sugar replacement. Ultrasound treatment on pectin solution at shorter duration was able to further reduce the batter density which increases the cake aeration by producing higher cake volume with lower hardness compared with non‐treated pectin in lower level of sugar replacement

Rheological and textural studies of fresh and freeze-thawed native sago starch-sugar gels. I. Optimisation using response surface methodology.

A three-factor–three-level Box–Behnken design was adopted to study the simultaneous effects of two compositional variables (6–8% sago starch and 25–35% sugar) and one processing variable (shearing speed of mixer at 20–50 rpm) on textural and rheological properties of gels. Analysis of variance (ANOVA) was performed to evaluate the potential interactive and quadratic effects between these variables. Sago starch and sugar levels both increased gel stiffness and viscoelasticity. Shearing, on the other hand, reduced gel stiffness and viscoelasticity. Ridge analysis was performed to estimate the values of these variables which maximised and minimised the textural parameters of hardness, gumminess, resilience, cohesiveness, and springiness. Pearson correlations among various rheological and textural properties of gels were studied. The processing conditions that contributed to an optimum gel setting were found at sago starch of level of 7.69%, sugar of 30.29%, and shearing speed of 45.86 rpm