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William Bartlett (Pyrus communis) pears were diced, packaged and subjected to a short continuous microwave treatment (4.7 min) which increased the temperature from 19.92 ± 1.36 to 101.11 ± 2.50 °C. Retorted samples were processed at 95.40 °C for 18.0 min for comparison. Recorded temperature data were used to calculate C, D and F values. Brix, pH, colour, texture, microbial counts, microstructure and volatile profiles of both treated samples were analysed immediately after process and after 1, 2, 4 and 6 weeks of storage at 4 °C. The C, D and F values of microwaved pears were significantly (p < 0.05) lower compared to those of retorted samples. Both methods of processing resulted in products with standard plate count of < 10 cfu/g during 6 weeks of storage at 4 °C. Microwave processing offered a final product with a total colour difference in the same range as the retorted samples. Polyphenol oxidase enzyme was inactivated below the detection level by both microwave processing and retorting. Microwaved samples also maintained cell wall integrity, although the intercellular intactness was slightly weakened and prevented the final product from developing water-soaked appearance. During storage, volatile profiles of microwaved samples showed significant (p < 0.05) differences, whereas the retort samples showed minimal changes. In comparison to conventional retorting, a short microwave treatment can result in a superior quality end-product with a comparable microbiological quality and a minimum shelf life of 6 weeks at 4 °C.

Tempe is a soy fermentation product and has been associated with many health benefits. It is usually consumed after 48 hours of fermentation; however extended fermentation is sometimes favoured. Since cooking involves water, it is of interest to study the health benefits of tempe water extract. In this study, we focused our study on total phenols, total flavonoids, DPPH free radical scavenging activity, cytotoxic activity, and identification of the main flavonoids. Our findings demonstrated that concentration of water-soluble flavonoids in tempe increased as fermentation time was prolonged. Fermentation for 60 hr resulted in extracts with very noticeable cytotoxic activity against MCF-7 cancer cell line (IC50 of 8.70 µg/ml). The cytotoxic activity of the extracts was fermentation time-dependent following non-linear relationship. The activity showed strong inverse correlation with total phenols and flavonoids in the extracts. LC-MS/MS data suggested that extracts from control and 24-hr fermented tempe demonstrated the highest responses for genistein, genistin, daidzein, daidzin, and glycitein, compared to those of other treatments and therefore suggested that excessive amount of the isoflavones, particularly genistein, induced cancer cell proliferation but lesser yet optimum concentration (observed at 60 hr-fermentation) contributed to otherwise effect.

Modified cassava flour (mocaf) is an alternative food ingredient used in preparation of biscuits as a binder and a carrier of folic acid fortificant. This work aimed to evaluate the mocaf addition with natural folic acid fortificants in two infant biscuit formulations. Mocaf was added at concentration of 0, 0.3, 0.6, 1.2, and 2.4% (w/w, control formula of infant biscuit) with folic acid fortificant A (mixture of nixtamalized corn, soy tempeh and fermented broccoli) and B (mixture of nixtamalized corn, mung beans tempeh and fermented broccoli). The optimum condition was achieved at mocaf concentration of 0.3% and resulted in infant biscuits A and B with folic acid content of 212.23 µg/mL and 438.74 µg/mL, dissolved protein 27.41 mg/mL and 28.88 mg/mL, total sugars of 358.20 mg/mL and 322.72 mg/mL, reducing sugars of 35.10 mg/mL and 39.78 mg/mL, total solids of 94.82% and 92.43%, respectively. The formulations of biscuits A and B increased folic acid content by 80.05% and 199.55% compared to the counterpart without mocaf addition. The predominant folic acid monomers had molecular weight of 442 m/z. Volatile compounds were identified as acetic acid, furan, and fatty acids. Biscuits A and B displayed average particle size of 69.07 μm and 69.78 μm with hardness of 8.44 N and 16.94 N, and lightness of 35.68 and 36.86, respectively.

Coffee is a popular beverage that is consumed worldwide. Habitual coffee drinking is associated with cancer risk reduction including pre- and post-menopausal breast cancer. The invert correlation between coffee intake and breast cancer risk is weak, therefore coffee is potential for functional beverage. Coffee should be taken for several times per day to get its benefit. Compounds which give the cancer reduction effect are still debatable, they can be compounds with antioxidant or non-antioxidant properties. Robusta coffee from Lampung has a special meaning for Indonesian coffee lovers due to its strong aroma and flavour with affordable price. In order to observe the anticancer activity of Lampung Robusta coffee, its aqueous methanol extract was passed through a chromatography column containing polyamide with aqueous methanol as the eluent with a gradient of 10%. A total of 54 fractions were obtained and labelled as A to K fractions. Chlorogenic acid was detected in fractions A and B. Meanwhile, it was not detected in other fractions including G fraction. This G fraction, however, was the only one to show cytotoxicity against MCF-7 breast cancer cell line. This result suggests that this fraction contains potential compounds with anticancer activity.

Compounds derived from natural sources have the potential use for food safety because of the antimicrobial properties. Today, consumer awareness on the potential negative effects of synthetic preservatives on health has sparked interest for researchers in the development and use of natural products in food. Antimicrobial testing was conducted on three gram negative bacteria, four gram positive bacteria and three fungi by micro dilution of ethanol, methanol, ethyl acetate and n-hexane extracts of bay leaf. The test results showed that all extracts did not have antimicrobial activity against gram negative bacteria. While, for gram-positive bacteria there are some extracts that have activity against certain bacteria, namely ethyl acetate extract and n-hexane against gram-positive MS = Mycobacterium smegmatis ATCC 70084 and methanol extract against gram-positive bacteria ML = Micrococcus luteus DSM 1790). All extracts have anti fungal activity against MH = Mucor hialisalis DSM 2656. It can be concluded that bay leaf extract using a variety of organic solvents shows selective antimicrobial activity against certain gram positive bacteria and fungi however no activity against gram negative bacteria.

The effect of high pressure–thermal processing (HPTP), in the range of 0.1–600 MPa and 100–140 °C for up to 60 min, on colour change and proteolysis of reconstituted skim milk (10% w/w) was investigated. The kinetic results showed that colour change (Δ E ab ) and proteolysis (determined by chromatography) increased with both increasing temperature and pressure. The apparent reduction of free amino groups in skim milk, indicating sugar conjugation to milk proteins/peptides, was accelerated with increasing temperature, but decelerated with increasing pressure (at constant temperature) at higher temperature. The milk’s colour changed drastically at 400 MPa where most of the milk proteins formed coagulates and left the solutions nearly translucent. Mathematical models describing the kinetics of colour change, proteolysis, and free amino acids reduction as a function of pressure and temperature are proposed.

Tempe is a functional food prepared from soybeans through Rhizopus spp. fermentation, originated from Indonesia. The present study was performed to investigate the cytotoxicity and antioxidant activity of tempe prepared from fermentation for 0-156 h and extracted with ethanol. The cytotoxicity was assessed on MCF 7 breast cancer cells using alamarBlue™ method. The antioxidant activity determined by DPPH free radical scavenging assay. The results indicated that ethanol extracts of 108 h tempe showed cytotoxicity potency at IC50 5.20 ± 1.01 μg/mL against MCF-7 breast cancer cell. Ethanol extract of 120 h tempe showed the highest antioxidant activity expressed as percent of inhibition, with no significant difference to those of 108 h tempe. It can be concluded that the cytotoxicity of tempe from 0-156 h of fermentation is correlated to their corresponding antioxidant activtity. Longer fermentation time, up to 108 h, increased the ability of tempe to inhibit the growth of the oxidative reaction and growth of MCF-7 breast cancer cells. Extended fermentation time, up to 156 h, tends to decrease the abilities of cytotoxicity and antioxidant activity.

Various herbal teas are available in the market and used for health maintenance or prevention of diseases. Previous studies by our research group showed that several boiled water extracts or organic solvent extracts of Indonesian mistletoes (benalu) and organic solvents extracts of Selaginella (cakar ayam) have in vitro and/or in vivo anticancer activities[1,2,3,4,5]. Therefore the aim of our to study the in vitro bioactivities (antioxidant, antidiabetes and cytotoxicity) of these plant materials as when prepared as herbal tea infusion. Four mistletoe samples (M1; M2; M3; M4) and one sample of Selaginella (S) were used in this study. DPPH free radical scavenging activity method was used for antioxidant. Inhibition of a-glucosidase activity method was used for antidiabetes. Growth inhibition to breast cancer cell line MCF7 method was used for cytotoxicity. The results showed that all mistletoes samples showed high in vitro antioxidant, antidiabetes and cytotoxicity, whereas the Selaginella sample showed significantly lower activitiy for antioxidant (about 5x less) and about half for antidiabetes and cytotoxicity. These results suggest that for further development of functional drink, mistletoes samples showed better potential than selaginella when used as a single material in herbal tea infusion. However we should make into account the possibility of synergistic effect on bioactivities when mixtures of two or several plant materials were present in the herbal tea formulation. Currently formulation of herbal teas using various mixture of different mistletoes as well as mixture of mistletoe and Selaginella are still under investigation.

High pressure processing (HPP) can induce structure development in macromolecules which are distinct from those of conventional thermal treatments. Gelation properties of whey protein (5-20% w/w) upon 15min HPP at 600MPa and 5 or 30°C (initial sample temperatures) were examined in the presence and absence of 5% w/w gelatin. The values of storage modulus (G') in pressure treated mixed gels were below those of their counterparts thermally treated at 80°C. Mixed systems subjected to HPP in the solution state possessed higher G' than the mixed systems subjected to HPP in the form of gels. The cooling profile of G' in pressurised mixed solutions was similar to that of the gelatin solution, which indicates that HPP resulted in a high degree of gelatin continuity. Confocal images confirmed that gelatin was the continuous phase whilst whey protein aggregated in discontinuous inclusions within the pressurised mixed systems.

Tempe is an Indonesian fermented soy bean, produced by using mainly Rhizopus oligosporus. Diversification of tempe raw materials is required for better food security, e.g., using lupin. The potency of lupin bean has been studied as a substitute of soy in tempe production. Nutritionally, lupin bean offers additional advantages over soy bean, i.e., it has a lower level of many anti-nutritional factors (ANFs) but contains higher protein (32-36%) than most pulses. The objectives of this study were to select the most suitable lupin bean from different particle sizes for tempe production and to characterize the quality of lupin tempe. In this study, the lupin tempe samples were analyzed for moisture content, firmness, aroma, and the total count of colony after 1 and 2 days of fermentation. Sensory evaluation was conducted by 17 Indonesian untrained panelists (hedonic) in three different days. The data were evaluated statistically using General Linear Model (GLM) and Tukey’s Honest Significant Difference (HSD). Results showed that the moisture content of lupin tempe ranged from 60 to 66%, higher than that of soy tempe (58.90%). Meanwhile, the firmness of lupin tempe was between 21.38-30.89 N. Mostly, tempes which were produced from ≤50% of particles sized ≥5 mm (L3, L5 and L6) exhibited poor quality in terms of firmness and aroma. The mean of total count of colony in lupin tempe were 3.0x104 CFU/g, lower than that of soy tempe (218x103 CFU/g), indicating a slower growth of mycelia on lupin beans. However, the overall acceptability of lupin tempe which was prepared from whole beans (L4 and L7) was not significantly different from that of soy tempe. Based on these quality and sensory tests, lupin tempe using whole lupin beans was recommended for substitute of soy bean in tempe production.

There is an increasing demand to tailor the functional properties of mixed biopolymer systems that find application in dairy food products. The effect of static high pressure processing (HPP), up to 600 MPa for 15 min at room temperature, on milk–gelatin mixtures with different solid concentrations (5%, 10%, 15% and 20% w/w milk solid and 0.6% w/w gelatin) was investigated. The viscosity remarkably increased in mixtures prepared with high milk solid concentration (15% and 20% w/w) following HPP at 300 MPa, whereas HPP at 600 MPa caused a decline in viscosity. This was due to ruptured aggregates and phase separation as confirmed by confocal laser scanning microscopy. Molecular bonding of the milk–gelatin mixtures due to HPP was shown by Fourier-transform infrared spectra, particularly within the regions of 1610–1690 and 1480–1575 cm−1, which reflect the vibrational bands of amide I and amide II, respectively.

Tempe is a nutritious food, prepared mostly from soybeans and was originated in Indonesia. Tempe is sometimes collected beyond its maturity age for culinary purpose. The studies of overripe tempe ranged from microbiology, chemical and nutritional changes, functionality and safety, to sensorial aspect. Study which follows pH and colour changes of tempe during fermentation, however, is scarce. The objectives of this study were to investigate and model the colour and pH changes of tempe and the mould mycelia during extended fermentation with Rhizopus spp. up to 156 hours. Our investigation revealed that both lightness soybeans and mycelia of the tempe decreased with increasing fermentation time while pH of the tempe increased. The decrease of both lightness followed simple cubic equations whilst the pH increased linearly with increasing time. The other a values of tempe decreased by one point in the first 72 h of fermentation and tended to increase later however did not reach the initial a value, The b value...

This review highlights the current knowledge on gelation of hydrocolloids induced by high pressure processing (HPP) of dairy products. Pressure-induced gelation of single systems (casein rich, whey protein rich, gelatin, and polysaccharide solutions) as well as rheological and thermo-mechanical effects of HPP on mixture systems are discussed. The mechanism of dairy protein gelation under pressure, their properties and microstructure, and potential application of HPP to improve physical properties of dairy products (cheese, yoghurt, and ice cream) are included. HPP is a promising tool for future manufacturing of structured dairy products with unique sensorial properties.

Cryomilling of rice starch was evaluated as a non-chemical way to modify starch structure and properties. Cryomilling in a liquid nitrogen bath (63–77.2 K) was done to Quest (10.80% amylose) and Pelde (20.75% amylose) rice starch at five different time frames (0, 15, 30, 45, and 60 min). The viscosity of the cryomilled rice starch decreased significantly (p < 0.05) with increasing milling duration, including peak viscosity, hot-paste viscosity, cold-paste viscosity, breakdown, and consistency. Increasing milling time significantly increased (p < 0.05) water solubility index and water absorption index. Infra-red spectroscopy and X-ray diffraction crystallography both showed that the crystallinity of the cryomilled starch decreased with increasing milling time. Differential scanning calorimetry (DSC) analyses showed that after 60 min cryomilling there was partial loss of crystallinity (86% for Quest and 91% for Pelde) of both cryomilled starches. The cryomilling process modified the rice starch by causing a loss of crystallinity, that reduced its pasting temperature and increased water absorption, and by fragmentation of starch (probably the amylopectin fraction) that reduced the viscosity and increased solubility.

Vitamin B6 test kit was designed as an alternative, affordable and user-friendly analysis tool for small and medium enterprises which process bananas. Its performance was evaluated twice with 70 respondents and the measurements considered satisfying when the results were laid in the range of one square deviation from the real value that determined by spectrophotometer. Performance tests results then compared to pH measurement using pH indicator, the more familiar test kit that also rely on human ability to distinguish color. The first performance test to respondents that closely related to chemical measurement got 33 success results and 29 respondents gave satisfying results which was comparable to pH measurement that gave 31 of 33 satisfying results. The second performance test was conducted by 70 respondents which involving respondents with background that unrelated to chemical measurement. As much as 34 success results for both measurements from the related group but only 32 and 27 success measurements for pH measurement and Vitamin B6 measurement using kit, respectively, from the unrelated group. The second performance test results for pH measurement did not give significant difference with the second one, 34 of 35 satisfying results from closely related group and 27 of 32 from unrelated group. Second performance test results for Vitamin B6 was significantly different from the first one since the respondents required to conduct the measurement twice and the results were reported as average values. Vitamin B6 kit gave 23 of 61 satisfying results with 15 of 34 were from the closely related group and 8 of 27 from the unrelated group. Data from closely related group from second performance test were further analyzed by considered as two separated measurements and compared to the results from the first performance test. It was found that measurement conducted first gave only 2 of 34 satisfying results compared to 22 of 34 from measurement conducted at second. The results were also recapitulated and analyzed based on background and gender. Closely related group gave 44.12%, 29.41%, 26.47% satisfying, query and unsatisfied measurement results, respectively. These results were better compare to the unrelated group that only gave 29.63%, 25.93% and 44.44%. Female respondents gave 36.36%, 36.36%, 27.27% satisfying, query and unsatisfied measurement results, respectively, which better than male respondents that gave 41.18%, 5.88% and 52.94%. Vitamin B6 kit had good performance as a test kit candidate but still required many improvements so the measurement results doesn’t affected by gender, user background and number of conducted measurement. Better design of color chart was a proposed improvement to reduce the fatigue of eye's conical cell that will be conducted in the next study.