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Aloe vera contains a phenolic compound that has bioactive activity. Previous research showed that microencapsulation of aloe vera powder with maltodextrin as an encapsulation agent produced instant aloe vera with high antioxidative activity. The problem was the hygroscopic instant caused rapid moisture and oxygen absorption during storage, therefore decreasing the instant aloe vera antioxidative activity periodically. The aim of this research was to evaluate the antioxidative activity stability of instant aloe vera during storage. The processing of instant aloe vera through a reconstituted aloe vera powder with water with a ratio of 1:120 and then added with 2.5% maltodextrin as the encapsulating agent. The solution was then inserted into a spray dryer with an inlet temperature of 130oC, an outlet temperature of 103oC, and the flow rate of the solution is 350.0 mL/h. The resulted instant aloe vera was divided into 15 packs with a weight of 25 g, and each sample was wrapped with polyethylene plastic film with 0.80 mm thickness and then was stored at 25oC with a relative humidity of 75%. The sample was conducted in triplicate. The moisture content, and antioxidative activity that was based on the ability to capture 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical (RSA) and lipid peroxidation inhibition were analyzed every week until the critical condition was achieved at a moisture level of 12%. The research showed that the radical scavenging activity (RSA) and lipid peroxidation inhibition of instant aloe vera before storage were 16.34±1.22% and 39.33±1.68%, respectively, whereas in the critical condition the RSA was 3.63±0.04% and the lipid peroxidation inhibition was 22.31±0.02%. Based on their antioxidative activity, the appropriate storage time of instant aloe vera was about 12 weeks in polyethylene plastic film of 0.08 mm thickness

The aim of this study was to evaluate calcium fixation and calcium binding in calciumfortified rice. Calcium-fortified rice was made by soaking (infusing) rice in a Ca-lactate or Ca-gluconate solution at temperature of 80oC for 20 mins. The rice types used in this study were low-, medium- and high amylose rice, represented by Memberamo, Ciherang and IR-42 rice varieties. Calcium retention in rice was tested by washing and dialysis, and calcium levels in the rice were determined by Atomic Absorption Spectroscopy. Calcium fixation was determined by using an FT-IR infrared spectrometer based on the changes in infrared spectra of the functional groups of -OH and C-O. The research showed that calcium retention in rice after washing was between 86.23% - 94.38% (Ca-lactate) and 89.37% - 90.15% (Ca-gluconate), Ca retention after dialysis was between 37.49% to 44.13% (Ca-lactate) and 37.40% to 42.86% (Ca-gluconate). The addition of Ca-lactate or Ca-gluconate to rice caused a decrease in the absorbance value and the absorption band area square at a wave numbers 3425 cm-1 (-OH group) and 1300-1000 cm-1 (C-O stretching vibration). Based on these data and the retention of Ca2+ after washing and dialysis, the Ca2+ in fortified-rice was bound by hydrogen bonding to form Ca-hydrate and by ionicdipole bonding with –OH group of starch molecules, and/or trapping in gelatinized starch.

Instant aloe vera contains phenolic compounds which has antioxidative activity. However, this product is hygroscopic and damaged easily during storage. The critical condition of the instant occurs at the moisture content of 12.52 ± 0.24% (wb). Increasing the moisture content could accelerate oxidation of the phenolic compounds, thus decrease the antioxidative activity. Previous research showed that the antioxidative activity of instant aloe vera could lower the blood glucose. The purpose of this study was to evaluate the hypoglycemic activity of instant aloe vera during storage until the critical condition. The hypoglycemic effect was determined with the in vivo method using diabetic Wistar rats as experimental animals. The diabetic rats were fed with a standard feed combined with instant aloe vera which has been stored at various storage time i.e. 0, 2, 4, 6, 8 weeks and used normal rats fed without instant aloe vera as a control. The blood glucose was analyzed every week until 4 weeks. The research showed that the diabetic rats fed with standard feed without instant aloe vera had high blood glucose (219.40 mg/dL) after 4 weeks treatment. Otherwise, the blood glucose of diabetic rats fed with instant aloe vera decreased from 214.00 mg/dL to 97.57 mg/dL after 4 weeks.