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The lipolytic yeast Yarrowia lipolytica produces cell-wall-associated lipases, namely Lip7p and Lip8p, that could have interesting properties as catalyst either in free (released lipase fraction-RLF) or cell-associated (cell-bound lipase fraction-CBLF) forms. Herein, a mixture of waste soybean frying oil, yeast extract and bactopeptone was found to favor the enzyme production. Best parameters for lipase activation and release from the cell wall by means of acoustic wave treatment were defined as: 26 W/cm 2 for 1 min for CBLF and 52 W/cm 2 for 2 min for RLF. Optimal pH and temperature values for lipase activity together with storage conditions were similar for both the free enzyme and cell-associated one: pH 7.0; T = 37 °C; and > 70% residual activity for 60 days at 4, - 4 °C and for 15 days at 30 °C.

The aim of this study was to evaluate the effect of ricotta whey (RW), cheese whey (CW), and butter whey (BUW) as replacers of whole milk (WM) at different ratios (0:100, 25:75, 50:50, 75:25, and 100:0) in the physicochemical and sensory qualities of ice cream. All formulations, including a commercial sample used as reference, were analyzed for nutritional composition, energy value, pH, titratable acidity (TA), melting behavior, desorption index, instrumental color properties, instrumental hardness, and consumer sensory testing. Overall, the addition of RW, CW, and BUW increased the moisture content, TA, melting rate, and redness (a*) and yellowness (b*) values but decreased the pH, lightness (L*) value, energy value, levels of ash, protein, lipid, and carbohydrate. As exception, CW did not influence the TA, and BUW resulted in lower lipid reduction and in lower hardness changes, and it did not affect the content of ash, protein, and a* and b* values of ice creams. Any ice cream formulation had dietary fibers and a desorption index. Ricotta whey and CW at all ratios and BUW at 25% did not affect overall liking compared with the commercial sample, whereas purchase intention was only decreased by the addition of BUW from 50 to 100%. Ricotta whey at 75 and 100% decreased melting velocity and creaminess, and BUW at 50, 75, and 100% increased hardness, TA, and cream flavor but decreased creaminess, which contributed negatively to overall liking. Therefore, the evaluated dairy by-products, especially RW and CW, have great potential for replacing milk in ice creams., (Copyright © 2020 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Tiger nut milk is a nutrient rich drink with great commercialization potential. However, it is highly perishable. Microencapsulation of tiger nut milk by a blend of inulin and modified tiger nut starch resulted in a product with good characteristics. The microspheres of lyophilized tiger nut milk were spherical with and average particle size of 1.01 μm. It's thermal degradation occurred above 346 °C, denoting an excellent thermal resistance. There was no significant structural alteration in the active material after microencapsulation and no loss of stability within 60 days, which confirms that this process enables the preservation of freshness and chemical characteristics of tiger nut milk. During 30-90 days, vitamin C contents were stable in the presence or absence of light. Microsphere with tiger nut milk presented a shelf life of 60 days. Total aerobic mesophiles and total fungi counts were below 10 6  CFU/mL, showing good microbiological stability., (Copyright © 2019 Elsevier Ltd. All rights reserved.)