A combined method implementing both xenon hydrate formation and the freezing process for the preservation of barley as a simulated food

• Published in: Journal of food engineering 2015-11, Vol.165, p.104-111
• Main Authors: Arunyanart, Thunyaboon, Siripatrawan, Ubonrat, Takeya, Satoshi, Noritake, Hiroko, Makino, Yoshio, Oshita, Seiichi
• Format: Article
• Language: English
• Subjects: Food processing; Freezing; Gas hydrates; Nuclear magnetic resonance; Preservation techniques; X-ray radiographic imaging techniques; Xenon
• ISSN: 0260-8774; 1873-5770
• DOI: 10.1016/j.jfoodeng.2015.05.017

•Xenon hydrate formation was used for reduction of bulk water before freezing process.•A combined method of both xenon hydrate formation and the freezing process (CXF) was used.•CXF could more effectively maintain sample tissue states than the freezing alone process.•Xenon hydrate formation in plant cells was observed by using an X-ray microscope.•Xenon hydrate formation occurred inside and surrounding the cells of sample tissue. Freezing clearly damages plant cells and tissues when ice crystals form, and these affect the quality and speed up the deterioration of frozen agricultural products. This study attempted to use a combined method of both xenon hydrate formation and the freezing process (CXF) to lengthen the preservation of barley coleoptile cells, as opposed to using the freezing alone process (FAP). Barley coleoptile cells were used in this study as the sample simulated food, and xenon hydrate formation was encouraged in samples at 1.0MPa and 1°C for 0.5, 1, 2, 3, 4 and 5h, respectively. The results showed that the amount of xenon hydrate in barley coleoptile cells increased with storage time, and that their cellular structure could be destroyed when increasing the amounts of xenon hydrate. Therefore, conditions under a xenon pressure of 1.0MPa at 1°C for 1h were used to control the amounts of implemented xenon hydrate. The process of CXF, including the introduction of xenon gas under a pressure of 1.0MPa at 1°C for 1h frozen to −20°C, was studied. Typical restricted diffusion phenomenon were determined using a nuclear magnetic resonance method, and it was found that CXF barley coleoptile cells were similar to those of fresh barley. In contrast, the FAP barley coleoptile cells showed unrestricted diffusion phenomenon. The results from X-ray radiographic images also suggested that the CXF process can preserve the shape of barley coleoptile tissues and, additionally, it was found that xenon hydrate formation occurred inside the cells and intercellular spacing of such cells. It can therefore be suggested that the assumed process of xenon hydrate formation in plant cells results in CXF being more effective for the preservation of plant cells and their tissues than the FAP process.