Citrus Processing

Highly purified sugar concentrate from a residue of citrus pigments recovery process

“…The more direct effect of this purification step was the strong increase of the ratio, which passes from 8.8 to 32.3. With regard to the microbial level, it increased to about 135,000 cfu/ml; the microbial contamination accepted in citrus processing ranges from 500 to 100,000 cfu/ml, on a single-strength juice basis (Kimball, 1999). The high contamination level of the deacidified sample needed an UF step to reduce the microbial count and remove most of the enzymes.…”

“…The chemical composition of PW is similar in many respects to that of a single strength orange juice but it is paler and bitter, and regarded as a lower quality product (Kimball, 1999). The starting sample was centrifuged before treatments with the purpose to remove the suspended solids, to minimize the presence of flavanone glycosides (narirutin and hesperidin) and to avoid the plug of the resin bed during the adsorption steps.…”

“…This residue is a column percolate of the anthocyanins adsorption and contains sugars (glucose, fructose and sucrose) as main components, together with a minor amount of acids, pectins and proteins. Like all liquid wastes, once produced this residue must be treated before disposal with remarkable expenses for the industries (Kimball, 1999). The efficacy of a series of unit operations based on adsorption and membrane processes to obtain a highly purified sugar concentrate was evaluated in this study with the aim of produce an high quality natural sweetener suitable in food and beverage industries.…”

Color and viscosity of watermelon juice treated by high-intensity pulsed electric fields or heat

“…PME activity was measured using the method described by Kimball (1991). Citrus fruit pectin (67-71% esterified), sodium chloride and NaOH were purchased from Acros Organics (NJ, U.S.A.), Rectapur (Fontenay, France) and Panreac Quimica (Barcelona, Spain), respectively.…”

“…On the other hand, decreasing the PME and PG action could limit the degradation of pectin substances. Thus, concomitant losses in viscosity and cloud stability could be diminished (Kimball, 1991;Rodrigo et al, 2006). Commonly, the activity reduction of deteriorative enzymes as well as the inactivation of microorganisms can be attained with the application of conventional thermal treatments.…”