الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Lime juice is considered a rich source of many bioactive compounds which have numerous health benefits. The quality of the juice changes under the influence of processing and subsequent storage. The present study aimed to evaluate the impact of the technological processes on physicochemical, microbiological and sensory properties of lime juice products; fresh, pasteurized lime juice and its concentrate (30º and 50º Brix) stored at 4.0±1.0ºC as well as sweetened lime juice powder stored at room temperature for eight weeks.The results obtained for lime juices (fresh, pasteurized lime juice and its concentrates 30º and 50ºBrix stored at 4.0±1.0ºC) showed that there were: gradual decreases in reducing and non reducing sugar, ascorbic acid, antioxidant activity, taste, color, flavor and overall acceptability during storage. The retention of ascorbic acid after storage at 4±1ºC for eight weeks was 56.14% of fresh lime juice, 53.53% of pasteurized lime juice, 51.57% and 66.83% of reconstituted juice prepared from lime juice concentrate (30º and 50ºBrix), respectively. During storage, there was a continuous increase in browning index in fresh, pasteurized and reconstituted juices. Moreover, an increase in titratable acidity was observed in fresh lime juice. There was a slight increase in free amino nitrogen content in fresh and pasteurized lime juice during storage time. pH value was increased in pasteurized and reconstituted juices prepared from lime juice concentrates (30º and 50º Brix) during storage time. As for the microbiological evaluation, most of lime juice samples showed microbiological count less than 30 CFU/ml, whereas the other samples did not contain any microorganisms, so it is considered not detected. Sensory evaluation of lime juices revealed that fresh, pasteurized, and reconstituted juice prepared from lime juice concentrate of 30º Brix had acceptable taste and color up to eight weeks storage, but reconstituted juice prepared from lime juice concentrate of 50º Brix had acceptable taste up to the fourth week and acceptable color up to the sixth week. The score of flavor was the highest in fresh and pasteurized lime juice up to the end of storage time. from the overall acceptability, all samples of lime juice showed decrement of overall acceptability during storage time.The results obtained for sweetened lime juice powder stored at room temperature were summarized as follows: gradual decreases in ascorbic acid, pH value, free amino nitrogen and antioxidant activity. Gradual increases in titratable acidity and browning index was observed. No significant change were found in reducing, non reducing sugar and total sugar during storage. As for microbiological evaluation, the results was less than 30 CFU/ml. As for the sensory evaluation (taste, color, flavor and overall acceptability) of sweetened lime juice powder, it was acceptable in all sensory tests until the end of storage time. It is therefore, the quality parameters of fresh, pasteurized and concentrates of lime juice were slightly changed during storage for 8 weeks at 4.0±1.0ºC and changed in sweetened lime juice powder during storage at room temperature. The results suggested that marketing of lime juice in pasteurized form under cooling conditions and sweetened lime juice powder could be stored more than 8 weeks at room temperature.