Bignay fruits are produced from wild trees of Antidesma bunius Spreng which can be found in India, Ceylon, and South East Asia countries. Each mature tree can produce hundreds of kilograms of fruits per year, so this fruit has the potential to be used as a raw material in juice and beverage industries. In addition, recent trends in consumer demand indicates that consumers are more inclined to demand products which can provide health benefits. In order to assess the potential of bignay fruit as a raw material for juice production, it is important to determine the health-promoting bioactive compounds contained in fresh bignay fruit juice. Therefore, the objective of this study was to determine the concentration of bioactive compounds in fresh bignay fruit juice. Results obtained from this study showed that bignay fruit juice contained 1202.5 mg GAE/100 mL of total phenolic, 436.602 mg/100 mL of anthocyanin, 48.931 mg/100 mL of ascorbic acid, and 3.78 mg/100 mL of flavonoid. The scavenging activities obtained from DPPH and ABTS methods were 0.110 mg/mL and 0.126 mg/mL respectively. The above results indicate that bignay fruits contain health-promoting chemical compounds and can be used as a natural source of antioxidants.

Ohmic heating is considered as a novel technology for pasteurization. Ohmic heating rate is highly influenced by the electrical conductivity of the products. The heating rate and the stability of anthocyanin during ohmic heating need to be investigated in order to analyze the viability of ohmic heating for pasteurization of mulberry juice. Mulberry juice was heated using three different temperatures (80, 85 and 90°C) during 90 minutes. Electrical conductivity of mulberry juice increased from 0.014 Sm−1 at the initial of heating (32°C) to 0.033 Sm−1 at 90°C and the average heating rate was 0.568°C/s. The heating rate and electrical conductivity increased linearly with the increased in temperature. Degradation kinetic of anthocyanin followed the first order kinetic models with R2 > 0.9. The k-value of anthocyanin degradation increases along with the increasing of temperature ranging from 8 – 15 × 10–3/min. Anthocyanin shows relatively high temperature dependence with 135.83 kJ/mol energy activation value. Based on the heating rates obtained from this study, ohmic heating could be used as an alternative pasteurization method for mulberry juice.

Increasing awareness on healthy lifestyles escalated the demand for health beneficial products which lead to the creation of minimally processed products using novel technologies. Ohmic heating considered as an emerging sterilization technology which adopt the principle of High-Temperature Short Time (HTST) in thermal sterilization technology. Among the indigenous species of berry-like fruit grown in Indonesia are mulberry (Morus nigra), bignay (Antidesma bunius), and jambolana (Syzygium cumini). This berry-like fruits possess great potential as raw materials for juice industries. In order to evaluate the applicability of ohmic technology for sterilization of juice and purees from these fruits, a stationary ohmic heating system has been built and tested on these three types of fruit juice. The electrical conductivities, heating rates, and system performance coefficients were measured. This study found that the electrical conductivities of all these fruit juices were ranging from 0.128 to 0.430 S.m−1 which increased linearly with temperature. The heating rates were 0.57-0.66 °C/s and the SPC values were ranging from 0.64 - 0.81. This study concluded that ohmic heating is suitable for sterilization of these three types of fruit juices as it could provide a short heating time and a high coefficient of performance. However, the designed ohmic heating system seems to suit better for jambolana juice than for mulberry and bignay juice.

The effect of ohmic heating on bioactive compounds in bignay (Antidesma bunius) fruit juice during ohmic heating were evaluated. The parameters measured were total phenol, anthocyanin, flavonoid, and antioxidant activity. Ohmic heating was conducted at 70, 90, and 110 °C, and samples were collected at heating times of 0, 15, 30, and 45 minutes. Electrical conductivity of bignay fruit juice increased linearly with temperature with values ranged from 0.012 S/m at 32 °C to 0.039 S/m at 110 °C. Insignificant change in total phenol was observed, while anthocyanin and flavonoid showed significant degradation and the degradation kinetics followed the first-order kinetic model. The degradation rate constants for anthocyanin ranged from 0.0016 to 0.0213 min-1 with activation energy (E a) of 63.880 kJ/mol and the degradation rate constants for flavonoid were in the range of 0.0107 to 0.0209 min-1 with activation energy of 18.210 kJ/mol. Antioxidant activities (IC 50) obtained from DPPH method ranged from 0.106-0.168 mg/mL while those obtained from ABTS method ranged from 0.131-0.161 mg/mL. The results indicate that anthocyanin and total phenol in bignay fruit juice is much more stable during heating compared to flavonoid.

Ginger (Zingiber officinale var. rubrum) is a rhizome plant that can benefit health, fitness and be used as a spice. The content contained in ginger can prevent and treat various diseases and act as an antioxidant and anti-inflammatory agent. The cultivation of ginger plants requires adequate nutrients and water for development and growth. Crop water requirements are influenced by crop coefficients which vary according to the plant growth stage. The crop coefficient values are needed for irrigation management and increasing irrigation efficiency. The main objective of the current study was to investigate the crop coefficient value of ginger by lysimeter. Lysimeter is a water balance device with the principle of mass conservation, where the input is rainfall and irrigation while the output is percolation and evapotranspiration. The rainfall during the investigated period was 0–62.82 mm·day−1, humidity 70.7–89.4%, and air temperature 23.7–32.9 °C. The crop coefficient of ginger increased during the vegetative growth period, i.e., 0.997 in the seedling stage, 1.072 in the tiller stage, and 1.138 in the advanced vegetative stage. The crop coefficient of red ginger was determined using a lysimeter quite accurately, with a coefficient of determination value (R 2) 0.950 and a significant value of F less than 0.05.