Comparison of thermal, ultraviolet-c, and high pressure treatments on quality parameters of watermelon juice

Effect of UV-C irradiation and heat treatment on the shelf life stability of a lemon–melon juice blend: multivariate statistical approach

“…For example, Tran and Farid (2004) reported that UV-C treatment was able to inactivate only 5% of PME enzyme and did not prevent the cloudiness of the orange juice after UV treatment (73.8 mJ/cm2 UV dose). Moreover, Zhang et al (2011) observed 35% residual PME activity in watermelon juice subjected to a UV dose of 9.7 J/mL. Sew, Ghazali, Martín-Belloso, and Noranizan (2014) also reported that PME enzyme could not be inactivated in pineapple juice exposed to UV-C irradiation (11.23 mJ/cm 2 UV dose).…”

Extending the Shelf Life of Fresh Marula (Sclerocarya birrea) Juice by Altering Its Physico-Chemical Parameters

“…It is also noted that the microbicidal activity of high pressure is enhanced by low pH or temperatures above and below ambient. High hydrostatic pressure acts primarily on non-covalent linkages, such as ionic bonds, hydrogen bonds and hydrophobic interactions, and it promotes reactions in which there is an overall decrease in volume (Adams and Moss, 1995;Indrawati et al, 2008;Sampedro et al, 2008;Chao, et al 2011). It can have profound effects on proteins, where such interactions are critical to structure and function, although the effect is variable and depends on individual protein structure.…”

“…As a general rule vegetative bacteria and fungi can be reduced by at least one log cycle by 400 MPa applied for 5 min. (Indrawati et al, 2008;Sampedro et al, 2008;Chao et al, 2011) Bacterial endospores are more resistant to hydrostatic pressure, tolerating pressures as high as 1200 MPa. Their susceptibility can be increased considerably by modest increases in temperature, when quite low pressures (100 MPa) can produce spore germination, a process in which the spores lose their resistance to heat and to elevated pressure.…”

“…Hydrostatic processing has a number of appealing features for the food preparations such as Marula fruit juice. (Indrawati, et al, 2008;Sampedro, et al, 2008;Chao, et al, 2011) It acts instantly and uniformly throughout a substance so that the processing time is not related to container size and there is none of the penetration problems associated with heat processing. Nutritional quality, flavour, appearance and texture resemble the fresh material very closely.…”

“…To the consumer where it has been used it is regarded as a 'natural' process with none of the negative associations of processes such as irradiation or chemical preservatives. ((Indrawati, et al, 2008;Sampedro, et al, 2008;Chao, et al, 2011) Appertized foods include those which are hermetically sealed into containers, usually cans, and then subjected to heat process in-pack. While this has been hugely successful as a long term method of food preservation, it does require extended heating periods in which a food's functional and chemical properties can be adversely affected.…”