Quality improvement of manuka honey through the application of high pressure processing

The quality of honey is known to be compromised when it goes through thermal processing due to its negative impact on the unstable and thermolabile honey components which originated from the nectar and bees themselves. This present work is undertaken to access the use of an emerging food preservation technique known as “High Pressure Processing” for treating honey, as an alternative to the conventional thermal processing. In this thesis, honey quality has been addressed by measuring the effects of high pressure processing parameters (pressure, time and temperature) on nutritional properties of honey, namely total phenolic content and antioxidant activity. Honey samples, contained in small pouches, were subjected to different pressures (200-600 MPa) at close to ambient temperatures (25-33°C) for different holding times (10 to 30 min). Thermal processing (49- 70°C) was also carried out for comparison purpose. Results demonstrated that high pressure processing operated at 600 MPa for 10 min has capability to increase significantly the total phenolic content and antioxidant activity by 47% and 30%, respectively. Besides, the result showed that high pressure processing can maintain the natural colour of honey which relates directly to consumer perception, while retaining its shear-thinning behaviour and viscosity with no significant changes (p > 0.05). High pressure processing can also control hydroxymethylfurfural (HMF) concentration in honey during process within the standard limit, 16.93 to 18.76 mg/kg (which is below than the maximum allowed limit of 40 mg/kg). This work also reveals that high pressure processing can enhance antibacterial activity of Manuka honey significantly. It shows an increase in the percentage inhibition of Staphylococcus epidermidis from 64.15 ± 5.86% to 84.34 ± 7.62% when honey was subjected to 600 MPa. Storage studies for one year at room temperature (25°C) demonstrated that high pressure-treated samples have a good retention to the physicochemical, nutritional and rheological properties of honey throughout storage, which confirms that the positive effect of high pressure on honey is not a temporary effect. Whereas, an insight study on the safety part showed that the Saccharomyces cerevisiae cell varied linearly with ° Brix, indicating that food compressibility has a significant role in the microbial inactivation

Metabolite profiling of heat treated whole palm oil extract

The chemically complex and diverse nature of the plant metabolome require different platform technology to entire range of metabolites. An ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) technique was developed to profile and identify a set of small-molecule metabolites found in heat treated whole palm oil extract. An investigation was carried out on the effect of heat treatment on the yield, quality and metabolites profile for whole palm oil extract. Palm fruits were collected, cleaned and sterilized for 0, 20, 40 and 60 minutes. The kernels were then stripped from the sterilized fruit to get the pulp (mesocarp part) and later the pulp was pressed using small scale expeller. The resulting puree was centrifuged at 4000 rpm for 20 minutes. The results show that there was a significant difference between sterilization time of 0 minute and 40 minutes in yield and quality. Of all, the highest yield of oil of 19.9% was obtained at sterilization time of 40 minutes with DOBI value of 5.95 ± 0.08 and FFA of 1.44 ± 0.10. The MarkerView software version 1.2.0.1 analysis of the UPLC-ESI-MS/MS preliminary experimental data demonstrated the distribution and identity of several compounds in the whole palm oil extract for 40 minutes sterilization and 0 minute of sterilization

Effect of thermal and non-thermal treatment on the quality of honey: a review

In recent year, there has been an increasing amount of studies on the quality of honey particularly physicochemical properties and its nutritional value. Unfortunately, these properties will be affected when it is exposed to a temperature higher than 60°C during the conventional thermal processing and also altered its nutritional properties such as antioxidant activity and brown pigment formation. Hence, non-thermal processing that might be proven to be significant benefit, applied without causing significant heating that can damage taste, texture and nutritional value of honey. Although there are many research has been done on non-thermal processing on the bio-compounds in various foods in various foods, the application of non-thermal processing for the enhancement of the quality of honey is underexplored. By studying the effects of non-thermal processing on the quality of honey, it will help to improve the use of honey and also a diversification in food products containing it

Storage Stability of α-tocopherol Extracted from Heated and Unheated Palm Oil Mesocarp

α-tocopherol is one of the eight vitamers in palm oil which known as powerful biological antioxidants. It is known as phytonutrient which is natural occurring bioactives. However, it has high affinity towards heat and light. An investigation was carried out on the effect of different heating time on the α-tocopherol concentration of the extracted palm oil mesocarp. The work was also aimed to determine the stability of α-tocopherol after stored for three months period. A set of samples were stored at room temperature range between 28ËšC - 32ËšC. Another set of samples were refrigerated at a temperature between -14ËšC to – 18ËšC. The result showed that the highest yield was obtained at 40 minutes of heating with 19.9 ± 0.21% (w/w). Statistical analysis showed that there was a significant difference in α-tocopherol content (p < 0.05) between room and freezer temperature storage. The results also showed that unheated sample records the highest losses of α-tocopherol with 65.42 ± 3.06% compared to heated sample which is 39.10 ± 1.78%

Numerical study of jet impingement cooling on a smooth curve surface

Impinging jets are a best method of achieving particularly high heat transfer coefficient and are therefore employed in many engineering applications. In this study we seek to understand the mechanism of the distributed heat on the curve surface with the goal of identifying preferred methods to predicting jet performance. The goals that have been achieved in the numerical results displayed are determine the influence of impingement jet characteristics on thermal and flow field on a curve surface, determine the variation of Nusselt numbers (NuD) along the curve surface in order to understand the heat transfer characteristics and study the effect of position (in the center, in the mid and in the end) and angle (α=90°, 60° and 30°) of jet impingement on curve surface, different Reynolds numbers (ReD) in range of (5000, 6000, 7000, 8000 and 9000). The program, which was extracted results it is (GAMBIT 2.4.6) and (FLUENT 6.3), simulation is (2-D) in submerged jet flow and the continuity, momentum and energy equations were solved by means of a finite volume method (FVM). This study covers the effect of different Reynolds numbers (ReD) on average Nusselt numbers (Nuavg) and local Nusselt numbers (NuD). From the result, the average Nusselt numbers (Nuavg) increased with the increase of Reynolds numbers (ReD) for all cases, in comparison between different positions (center, mid and end), of nozzle on curve surface at angle (α=90°) the maximum value of average Nusselt numbers (Nuavg=388.3) is found when the nozzle locate in the end followed by the mid position and smallest value of average Nusselt numbers (Nuavg=182.25) in the center of curve surface. In case of slant angle (α=60º) the maximum value of average Nusselt numbers (Nuavg=387.47) is found when the nozzle locate in the end followed by the mid position and smallest value of average Nusselt numbers (Nuavg=308.3) in the center of curve surface

High Pressure Processing of Honey: Preliminary Study of Total Microorganism Inactivation and Identification of Bacteria

Due to the demand for better quality and safety food as it provides health benefits, the study of innovative high pressure processing (HPP) is currently one of the most interesting researches in food processing and preservation. As an alternative to classical thermal processing, HPP has potential to produce high quality foods that are microbiologically safe with ‘fresh-like’ characteristics and improved functionalities. In present work, the use of HPP will be investigated for its ability to inactivate bacteria spores, the heat resistance microbes. Preliminary results show that it is possible to use HPP to inactivate microorganisms present in high sugar content foods, particularly in Manuka honey. Further investigation will be carried out to find an optimal combination of treatment pressure, temperature and time. This project will generate a new approach in honey processing which can guarantee the safety of honey without a compromise on its quality and natural freshness

Neem oil as biopesticides

Agricultural biotechnology is a wide logical method used to improve plants, animals, and microorganisms. The biotechnology cycle in the agricultural segment incorporates improving the harvests, living things, and microorganism's quality and resistibility by hereditary adjustment. Other than that, biotechnology in agriculture additionally known from the utilization of more secure natural sources to create an item that will be ready to ensure and build the creation of yields and domesticated animals, for example, manure and biopesticides. The World Health Organization (WHO) likewise had reported that the synthetic based pesticides would arrive at their constraints of utilization as it loses their adequacy after some time. This can be shown by the disclosure of pesticides obstruction bugs. The neem plant was accounted for as the top rundown spices that can possibly go about as a biopesticide; this is because of the presence of various dynamic mixes known as limonoids. The significant compound is the azadirachtin which assumes an essential job as bug sprays, and it executes the focused-on bugs by troubling their development and generative system. The neem oil biopesticides additionally are less harmful towards living beings and less contamination toward nature. In this way, the neem removed biopesticides are presently popularized and have been sold and utilized in different nations

A Comparative Study on Thermal and Non-thermal Processing of Kelulut Honey

Recent years have seen the various studies conducted on the kelulut honey based on their physicochemical and nutritional properties. The main concern in production of kelulut honey in maintaining the quality especially when it is being treated. Previous studies have shown that conventional thermal processing that comprises two phases of heating which are liquefaction and pasteurization will minimize the quality of kelulut honey in terms of its physicochemical and nutritional properties due to its heat sensitivity material criteria. In addition, the reduction in quality of honey due to the unsteady components, breakdown of vitamins and damage of enzymes when it heated at more than 60℃ in thermal processing. Hence, a systematic review is carried out to identify a suitable heat treatment for kelulut honey as compared to conventional thermal processing in treating honey. The search strategy was established in three databases (Google Scholar, PubMed and ScienceDirect) with the search keywords “(“Honeyâ€, “Kelulutâ€, “stingless beeâ€, “Trigonaâ€, “Meliponâ€, “Microwave heatingâ€, “Double boilingâ€, “HPP†or “High pressure processing†and “Ultrasoundâ€)â€. The data selection strategy was showed using PRISMA guidelines. A total of 311 journal papers were referred to complete this review, however, only 10 articles were highly considered specifically on the process of kelulut honey, where microwave heating, double boiling and high pressure processing (three articles respectively). Whereas, only two articles on analysis of ultrasound were found. From this literature review, it found that HPP provide higher benefit in improving physicochemical and nutritional properties of kelulut honey although it produces a lower change in colour if compared with other treatment. It can be concluded that HPP is the most potential in increasing the quality of kelulut honey followed by double boiling, ultrasound and microwave heating

Isolation and identification of polystyrene degrading bacteria from zophobas morio’s gut

Polystyrene (PS) and expanded polystyrene (EPS) are commodity plastics widely used in many industries. The increase of PS in the environment causes ecological threats. It has been observed that the beetle larvae feed on plastic packages, and this has drawn the researcher’s attention towards the complex system within the larvae’s gut where relationships between fungi, bacteria, and the insect host have been established. The objective of this study is to isolate and identify PS-degrading microbe from super worms. The study used polystyrene as a sole carbon source to isolate the positive PS-degrading bacteria. Five bacterial colonies which showed positive growth on the modified PS-agar plate were isolated. All five colonies of the PS-degrading bacterial isolates were identified using partial 16 S rRNA gene sequencing. The results showed a close relationship between Bacillus aryabhattai and Bacillus megaterium strains. An examination via biochemical studies for distinction was implemented further. Based on the morphological characterization and taxonomic method, the isolates were identified as Bacillus megaterium. The isolates' viability was tested using 2,3,5-triphenyltetrazolium chloride (TTC), and positive results were obtained with red-colored insoluble triphenylformazan (TPF) formed within 5 to 7 days. The isolation and identification of these bacteria from Zophobas morio’s gut may provide a promising source of a plastic degrading enzyme that can be further studied and manipulated in developing enzymatic biodegradation in plastic waste management

Antioxidants: nanotechnology and biotechnology fusion for medicine in overall

Antioxidant is a chemical substance that is naturally found in our food. It can prevent or reduce the oxidative stress of the physiological system. Due to the regular usage of oxygen, the body continuously produces free radicals. Excessive number of free radicals could cause cellular damage in the human body that could lead to various diseases like cancer, muscular degeneration and diabetes. The presence of antioxidants helps to counterattack the effect of these free radicals. The antioxidant can be found in abundance in plants and most of the time there are problems with the delivery. The solution is by using nanotechnology that has multitude potential for advanced medical science. Nano devices and nanoparticles have significant impact as they can interact with the subcellular level of the body with a high degree of specificity. Thus, the treatment can be in maximum efficacy with little side effect