Partitioning of predominant lipophilic bioactives (squalene, α-tocopherol and β-sitosterol) during olive oil processing

The partitioning of predominant lipophilic olive bioactives (squalene, β-sitosterol and α-tocopherol) in olive oil processing was studied for the first time using common integrated olive milling plant. 7% of the oil and 5% of the squalene present in the olives was lost in the last pomace. β-sitosterol and α-tocopherol, which are mainly concentrated in the seed of the olive fruit, was recovered in virgin olive oil to a lesser extent (66%, 67%) while 10% were lost in last pomace. Thus, the loss of β-sitosterol and α-tocopherol was higher than that of squalene and oil, due to nonrecovered bound forms. 19% of the α-tocopherol and 21% of the β-sitosterol loss was unaccounted for, which can be attributed to degradation of α-tocopherol and incomplete recovery of sterols from the olive and pomace matrices. This study provides a basis for process development studies.     

Semi-batch extraction of anthocyanins from red grape pomace in packed beds: experimental results and process modelling

A semi-batch extraction process of anthocyanins was studied in a packed bed. Methanol was used as solvent and the raw material studied consisted of skins of the tempranillo grape, which was obtained from the pomace from red wine vinification. The results show large diffusional effects due to strong control from the mass transfer. The best results were obtained using a high temperature and a high flow rate. A penetration model is proposed in terms of a bed of spherical particles. The model provides a value for the diffusion coefficient of the solute within the solid matrix. It can be seen that the adjustment of the model is satisfactory and that it is able to predict, to a reasonable extent, the yield of the extraction process.     

Fatty acid esters with short‐chain alcohols in two‐phase olive pomace oils

Two‐phase decanter olive pomace (TPOP) is the by‐product of a centrifugation system, used to produce olive oil, that separates olive oil and moist pomace. The water content in these olive pomaces is about 70%, while it was 45‐50% in the olive pomace stemming from three‐phase systems (oil, water, and pomace) and 30% in the old press system. The aim of this work is focused on quantification and changes undergone during olive pomace storage in ponds of esters of fatty acids with short‐chain linear alcohols, which can be considered as a refining loss. The results indicate that oil deterioration increases very rapidly, in particular when oil is extracted from the TPOP surface. Special attention should be paid to the storage of TPOP, establishing a maximum of 2 months in all cases.     

Sex phermone components of mulberry looper,Hemerophila atrilineata butler (lepidoptera: Geometridae)

(6Z-9S, 10R)-Epoxy-octadecene (SR-1) and (3Z, 6Z-9S, 10R)-epoxy-octadecadiene (SR-2) are sex pheromone components of the mulberry looper (MBL),Hemerophila atrilineata Butler. Compounds extracted from female MBL pheromone glands were identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry. In field experiments in China,SR-2,RS-2, or both combined were hardly attractive, butSR-2 in combination withSR-1 attracted significant numbers of MBL males. Synergistic behavioral activity ofSR-1 plusSR-2, but not of corresponding antipode mixtures, indicates enantiospecificity of MBL pheromone communication. Because blends of racemic and enantiospecific (SR)1 plus2 were similarly attractive, racemic1 plus2 may have potential for mass trapping or confusion of MBL males in commercial mulberry plantations.     

桑叶天然染料的萃取和稳定性研究

采用正交实验法及单因子实验法，有效地萃取桑叶染液并对其稳定性进行了研究和探讨。发现桑叶的水萃取液和盐酸萃取液的光吸收曲线相似。桑叶天然染料萃取的最大影响因子是萃取剂的种类，有效的萃取剂在本试验中是氢氧化钠，其萃取液的色浓度、光密度值大，氢氧化钠最佳浓度为20％。三种萃取液的光稳定性和抗还原性能均较好，其中H2O和HCl萃取液的抗氧化性能较弱，而NaOH萃取液的稳定性则较好，并且均可在一定的条件下保存几天，因此一次萃取一定量的桑叶染液可供给几天染色用，减少了提取桑叶染液的次数，节约了时间、劳力及能耗，有利于桑叶染料实用化的进程。     

Kinetics of ultrasonic extraction of polyphenols,anthocyanins and tannins from five different New Zealand grape pomaces

Polyphenols were extracted from five kinds of New Zealand grape pomace (Sauvignon Blanc, Pinot Gris, Gerwurztraminer, Merlot and Pinot Noir) at 30, 50 and 70 °C in an ultrasonic generator. The extraction kinetics for total phenol, anthocyanin and tannin were determined. The results of dynamics study showed that the extraction of total polyphenols, anthocyanin and tannin followed first-order reaction kinetics during the extraction at 30, 50 and 70 °C. The total phenolic content, anthocyanin conten, and tannin content of water–ethanol extracts from grape pomaces were compared, and the parameters in the extraction kinetics equations were determined. The extraction results showed that the Pinot Noir pomace extract had the highest total phenolic content of 59.95 mg GAE g⁻¹ pomace and tannin content of 79.93 mg EE g⁻¹ pomace. The anthocyanin content in Merlot pomace extract was the highest, which was 4.50 CE g⁻¹ pomace. The results might be of great significance for the development of grape pomace or its polyphenol and/or anthocyanin components as an antioxidant source with natural and inexpensive benefits.     

Improvement of the quality of gluten‐free sponge cake using different levels and particle sizes of carrot pomace powder

In this study, carrot pomace powder (CPP) with particle sizes of 210 μm (CPP210) and 500 μm (CPP500) was added in the gluten‐free sponge cake recipe. Flour (rice and corn flour, 1:1, w/w) was replaced with 0, 10, 20 and 30% CPP. With increasing the level and particle size of CPP, batter density, viscosity, consistency and firmness increased. The control cake had a dense, hard texture, irregular shape and low sensory scores. These properties improved with addition of CPP so that the cake density, hardness and cohesiveness reduced, while symmetry index and sensory scores increased. Varying the particle size of CPP had no considerable effects on most of the batter and cake properties, while increasing the level of CPP had great positive effects on the quality of batter and cake. Overall, addition of 30% CPP with either of the particle sizes resulted in an acceptable gluten‐free cake.     

Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste

The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.     

Biotechnological potential of industrial wastes for economical citric acid bioproduction by Aspergillus niger through submerged fermentation

Submerged citric acid (CA) bioproduction was carried out by Aspergillus niger NRRL‐567 using various industrial wastes, such as brewery spent liquid (BSL), lactoserum and starch industry water sludge. CA bioproduction was carried out by varying the temperature (25–35 °C), pH (3–5), addition of inducers, incubation time and supplementation with different proportions of apple pomace ultrafiltration sludge (APS). The results indicated that under the best conditions with 3% (v/v) methanol, the optimal concentration of 11.34 g L^?1 CA was recorded using BSL at pH 3.5 and temperature 30 °C after 120‐h incubation period. Supplementation of methanol resulted in an increase of 56% CA production. Meanwhile, under similar conditions, higher concentration of 18.34 g L^?1 CA was reported with the supplementation of BSL with 40% (v/v) APS having suspended solids concentration of 30 g L^?1. The present study demonstrated the potential of BSL supplemented with APS as an alternative cheap substrate for CA fermentation.