Optimisation of vacuum frying of gold kiwifruit slices: application of response surface methodology

Bioactive Compounds and Sensory Quality in Chips of Native Potato Clones (Solanum tuberosum spp. andigena) Grown in the High Andean Region of PERU

Native potatoes (Solanum tuberosum spp. andigena) have diverse pigments and are cultivated in Peru's high Andean regions; they are characterized by containing bioactive compounds that prevent various degenerative diseases. The study aimed to evaluate the physicochemical and sensory quality in chips of native potato clones grown at 3496 m altitude, for which the potatoes were cut into slices and fried in extra virgin olive oil at 180 °C for 200 s. This was determined by proximal analysis, reducing sugars, minerals, color, antioxidant capacity (AC), total phenolic compounds (TPC), and anthocyanins in fresh and chips; an instrumental characterization by FTIR and SEM and sensory tests were also performed. The native potatoes presented low moisture and reduced sugar contents; when frying, their bioactive properties improved, increasing AC, TPC, and trace elements, such as K, Mg, Ca, P, Fe, and Zn. To conclude, fresh clones have high yields in the field and are an essential source of nutrients and bioactive; the salt-free chips of clone B presented better physicochemical properties and greater sensory acceptance, closely followed by clone A. Both clones could be used as raw material by food companies that produce snacks to benefit high Andean agricultural producers.

Optimization of vacuum frying condition for producing silver carp surimi chips

In this study, we explored the feasibility of vacuum frying to produce crisp silver carp surimi chips. The influence of three process parameters (frying temperature, frying time, and slice thickness) on the quality parameters of vacuum-fried surimi chips (oil uptake, crispness, and optical properties) was investigated. The experimental results showed the optimal conditions were chosen as 2-mm surimi slice being vacuum-fried at 118°C for 2.5 min. Under these conditions, the oil content, breaking force, and color difference to commercial potato chips were 24.33%, 15.21 N, and 14.03, respectively. Additionally, we also measured the water loss during vacuum frying and the oil quality changes during storage of surimi chips. Results demonstrated the rapid loss of water content of surimi chips during vacuum frying and oil deterioration was kept at acceptable low level up to 100 days. Taken together, our study supported the applicability of vacuum frying technology to produce high-quality silver carp surimi chips.

Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food

Blends of yam, rice and corn flour were processed in a twin-screw extruder. Effects of yam flour (10-40 %), feed moisture content (12-24 %) and extruder barrel temperature (100-140 °C) on the characteristics of the dried extrudates was investigated using a statistical technique response surface methodology (RSM). Radial expansion ratio differed significantly (p ≤ 0.05) with change in all the independent variables. Highest expansion (3.97) was found at lowest moisture content (12 %) and highest barrel temperature (140 °C). Increased yam flour level decreased the expansion ratio significantly. Water absorption index (WAI) increased significantly with increase of all variables. However, water solubility index (WSI) did not change with change in yam flour percent. Hardness of extrudates that varied from 3.86 to 6.94 N was positively correlated with yam flour level and feed moisture content, however it decreased significantly (p ≤ 0.001) with increase of barrel temperature. Yam percent of 15.75 with feed moisture and barrel temperature at 12.00 % and 140 °C respectively gave an optimized product of high desirability (> 0.90) with optimum responses of 3.29 expansion ratio, 5.64 g/g dry solid water absorption index, 30.39 % water solubility index and 3.86 N hardness. The predicted values registered non-significant (p < 0.10) differences from the experimental results. Further study would include the sensory properties enhancement of extruded snacks and little emphasis on the chemistry of interaction between different components.