Improving Shelf Life, Maintaining Quality, and Delaying Microbial Growth of Broccoli in Supply Chain Using Commercial Vacuum Cooling and Package Icing

Poor and inconsistent quality is a major barrier to increasing produce consumption, and the lack of shelf-life after purchase is the quality issue at retail displays of produce. This research aimed to investigate and identify cooling techniques, namely vacuum cooling and package icing used in supply chains, and any resulting extension of broccoli shelf-life, maintenance of physicochemical quality, and delay in microbial growth at retail stores. Broccoli (Brassica oleracea var. italica cv. Montop) sustainably grown in the highlands of northern Thailand, Chiang Mai Province, under the Royal Project Foundation was experimented on vacuum cooling and package icing were selected to precool broccoli to 4 ± 1 °C. The effects of vacuum cooling using a final pressure of 0.6 kPa for 30 min and package icing using liner Styrofoam boxes (the best ratio of broccoli to crushed ice was 1:1 w/w) on physicochemical qualities, microbial growth, and shelf-life in simulated refrigerated retail displays were examined. The results illustrated that the shelf-life and quality of broccoli could be extended using both vacuum cooling and package icing. Both precooling techniques inhibited the yellowing of florets, provided high sensory scores, delayed microbial growth, and could be able to extend the shelf-life of broccoli. However, package icing offered greater potential for maintaining quality, especially retaining bioactive compounds, and extending shelf-life, thereby increasing the produce market window from 5 to 12 days at 8 ± 1 °C with 85% RH. Therefore, package icing was recommended in the supply chain for fresh broccoli cv. Montop grown in northern Thailand.

The effects of vacuum cooling to post-pasteurized honey on diastase enzyme activity and physical properties of Riau Forest Honey

Honey is defined as a traditional natural liquid which usually has a sweet taste derived from the nectar of flowers. The main component of honey is a natural saturated sugar solution consisting of a mixture of complex carbohydrates and contains various important micro-nutrients such as vitamins, minerals, enzymes, and organic compounds. These micro-nutrients are very susceptible to damage during the honey processing process. In this study, a cooling method in the form of vacuum cooling was applied with the aim of maintaining the micro-nutrients in honey. Vacuum cooling that is applied after the pasteurization process aims to release the latent heat trapped in the honey in a relatively short time and minimize damage to micronutrient, especially the diastase enzyme. The research design consisted of 2 factors, namely the volume chamber consisting of 12.5%, 25%, and 50%. The second factor is the cooling method which consists of conventional and vacuum cooling. The samples from the research were tested on diastase enzyme activity and the physical properties of honey such as moisture content, density, and acidity. The results showed that cooling with the vacuum cooling method had lower water content, low acidity, high density, and better diastase enzyme activity compared to conventional cooling.

ANALISIS KANDUNGAN ENZIM DIASTASE PADA MADU SINGKONG HASIL PROSES VACUUM EVAPORATION DAN VACUUM COOLING

Honey that has a moisture content above 22% should be done moisture reduction process. reduction of water content is done so that honey does not undergo fermentation and has a longer shelf life. One of the ways that can be used to reduce water content in honey is evaporation. Evaporation is of converting some of the water content in the material into steam by utilizing temperatures close to the boiling point of water. However, the minor content of honey, such as the diastase enzyme, is very sensitive to high temperatures. Therefore, vacuum evaporation is used so that the process uses a lower temperature to minimize the damage to the diastase enzyme. The research method was carried out in 3 stages, namely sampling, evaporation process, and sample testing. The results of this study indicate that the process of vacuum evaporation and vacuum cooling can change the proximate content of cassava honey to comply with SNI.

Analisa Kualitas Madu Singkong (Gula Pereduksi, Kadar Air, dan Total Padatan Terlarut) Pasca Proses Pengolahan dengan Vacuum Cooling

Honey is a natural liquid that is commonly used as an addition to food or drinks and has properties thatare believed to increase endurance and cure various diseases. Honey has different characteristics basedon taste, aroma, color. This can not be separated from the physico-chemical content of honey. Highwater content in honey can reduce the shelf life of honey because it can cause fermentation by yeast.So, in this study, cassava honey was processed using a vacuum cooling device designed by Mr. AnangLastriyanto from Brawijaya University with the aim of seeing the effect of changes in honey quality onlow temperature heating with vacuum pressure to reduce the water content of honey. After processingwith a vacuum cooling device, the reducing sugar content, moisture content and total dissolved solidsin the cassava honey are tested to show the effect of using a vacuum cooling device. Real honey has areducing sugar content of 52.43% and after vacuum cooling it becomes 55.06%. The water content ofreal honey is 27.2% to 11.22 after the vacuum cooling process. The total dissolved solids of the originalhoney was 68.75% Brix to 79.5% Brix after vacuum cooling.

Microstructure of Additive Manufactured Ti6Al4V by Electron Beam Melting

The electron beam melting-printed Ti6Al4V shows a great potential application for orthopedic implants and aerospace in recent years. A systematic study on the microstructure of additive manufactured Ti6Al4V by electron beam melting both parallel to and perpendicular to the building directions (Z axis) is presented in the present investigation. The results showed that the microstructure of the alloy was α lamina with HCP structure and β bar with BCC structure. The original β phase grew as columnar crystal along the direction of construction, showing an equiaxial shape in the cross section, numerous small α lamellae block the original β phase, and presenting a cluster distribution on the original β grain boundary, and a basket-like distribution in the original β grain. This may be due to the rapid cooling of the small pool after melting, the repeated heating of the subsequent constructed layer on the formed layer, and the subsequent limited vacuum cooling, resulting in the formation of the micro morphology, which leads to the original β grain boundaries broken, and the formation of a distinctive basket or widmanstatten structure [1, 2]. In addition, XRD results indicated that there was α′ martensite, part of which has been decomposes into α phases and β phases, SEM and TEM experiments also proved this. Of note is that random distribution dislocation was observed in TEM. Using EBSD results, and it may be understand that the sample build direction was parallel to [0001] crystal orientation and build plane parallel to (1210) and (1100) crystal facets.