Antioxidant capacity, fatty acids profile, and descriptive sensory analysis of table olives as affected by deficit irrigation

BACKGROUND

The influence of three irrigation treatments (T0, no stress; T1, soft stress; and, T2, moderate stress) on the key functional properties [fatty acids, sugar alcohols, organic acids, minerals, total polyphenols content (TPC), and antioxidant activity (AA)], sensory quality, and consumers' acceptance of table olives, cv. 'Manzanilla', was evaluated.

RESULTS

A soft water stress, T1, led to table olives with the highest oil and dry matter contents, with the highest intensities of key sensory attributes and slightly, although not significant, higher values of consumer satisfaction degree. Besides, RDI in general (T1 and T2) slightly increased green colour, the content of linoleic acid, but decreased the content of phytic acid and some minerals.

CONCLUSION

The soft RDI conditions are a good option for the cultivation of olive trees because they are environmentally friendly and simultaneously maintain or even improve the functionality, sensory quality, and consumer acceptance of table olives. © 2016 Society of Chemical Industry.

Physico-chemical, nutritional, and volatile composition and sensory profile of Spanish jujube (Ziziphus jujuba Mill.) fruits

BACKGROUND

Jujube fruit is eaten mostly fresh, but may be dried (Chinese dates and tea) or processed into confectionary recipes in bread, cakes, compotes, and candy. Given that the quality of jujube available on the market differs on account of various factors such as geographical environment, cultivar, processing conditions, and storage conditions, and that, for consumers, flavour and nutrition properties of jujube represent the major parameters in determining the quality of jujube, the main goal of this study were to determine the main physico-chemical properties of jujube fruits, sugars and organic acids profiles, protein, mineral constituents, volatile composition and sensory profile of jujube fruits. This would allow breeders to select cultivars with higher levels of nutrients and also enable increasing dietary intake by consumers.

RESULTS

Investigations showed that jujube fruit weight ranged from 4.8 to 29.3 g fruit(-1) . Four sugars (glucose, fructose, sucrose and sorbitol) and four organic acids (citric, malic, ascorbic and succinic acids) were identified and quantified by high-performance liquid chromatography in jujube fruits. Potassium, calcium and magnesium were the major mineral constituents in jujube fruits. Fifteen volatiles compounds were found in the aroma profile of jujube fruits (nine were aldehydes, three terpenes, one ester, one ketone and one linear hydrocarbon).

CONCLUSION

The results showed that Spanish jujube cultivars studied are a good source of vitamin C, and they have a low content of Na. The jujube cultivar with the most appreciated quality by consumers was GAL; the GAL fruits were sweet, crunchy, and had high intensities of jujube ID and apple flavour a long after-taste. Therefore, jujube grown in Spain has a great potential to be exploited for functional foods. © 2015 Society of Chemical Industry.

Quality attributes of pistachio nuts as affected by rootstock and deficit irrigation

BACKGROUND

In this work, the influence of two regulated deficit irrigation (RDI) treatments and three different rootstocks on the quality of pistachios was evaluated by analyzing different parameters: morphological analysis, physicochemical analysis and sensory analysis.

RESULTS

The results obtained in terms of the choice of rootstock revealed that Pistacia atlantica had increased production yields, nut weight, mineral content, higher intensities of characteristic sensory attributes and a higher degree of consumer satisfaction, than the other rootstocks studied. Moreover, the results established that the application of RDI on pistachio cultivation had no significant influence on production yield, weight, size, colour, water activity or mineral composition. Furthermore, T1 treatment (stem water potential < -1.3 MPa) resulted in higher intensities of characteristic sensory attributes and a greater level of satisfaction among international consumers.

CONCLUSION

These results confirm that the application of deficit irrigation (T1) contributes to an increase in overall product quality. Furthermore, Pistacia atlantica rootstock provided better yield and quality than the other rootstocks studied.

Pomegranate juice adulteration by addition of grape or peach juices

BACKGROUND

Pomegranate juice has gained a high reputation for its health properties and consequently is now a highly demanded product. However, owing to the limited production and high price of fresh pomegranates, adulteration of pomegranate juice seems to be happening. Hence it is imperative to establish criteria for detecting adulteration.

RESULTS

Addition of grape juice significantly increased the contents of Ca, Mg and Fe and especially tartaric acid and proline and simultaneously decreased the content of K. Addition of peach juice up to 10% (v/v) only resulted in a significant increase in sucrose content. Regarding the volatile composition, adulteration of pomegranate juice with grape juice resulted in significant increases in acetic acid, isoamyl butyrate and especially 1-hexanol and linalool, while adulteration with peach juice resulted in significant increases in butyl acetate, isobutyl butyrate, benzyl acetate and especially isoamyl butyrate.

CONCLUSION

The control protocols used in this study can serve as a basis for identification of pomegranate juice adulteration. It is important to highlight that it is necessary to simultaneously analyze and have results from several parameters to conclude that a particular pomegranate juice has been adulterated by mixing with another fruit juice.

Antioxidant activity, volatile composition and sensory profile of four new very-early apricots (Prunus armeniaca L.)

BACKGROUND

Very-early apricot cultivars are interesting owing to the fact that they will be available in markets before any other cultivar. In order to achieve good fruit quality, very-early apricots require appropriate size, weight and color, good balance of sugars and organic acids, proper content of bioactive compounds, relatively strong apricot aroma as well as acceptable sensory quality.

RESULTS

Physical, chemical, antioxidant and sensory properties showed important variations among apricot cultivars. These differences were basically attributed to genetic reasons. Four very-early apricot cultivars were studied, namely 'Mirlo Blanco', 'Mirlo Anaranjado', 'Colorao' and 'Mogador'. All of them showed proper size and weight, but their contents of organic acids, sugars and bioactive compounds were low and the number of volatile compounds was also low. However, very-early apricots showed an appropriate sensory profile for fresh consumption.

CONCLUSION

Regarding physical, chemical and volatile composition and sensory properties, very-early apricot cultivars could be recommended for fresh consumption. However, future research must be focused on increasing their contents of sugars, organic acids and bioactive and volatile compounds, perhaps via cultural practices such as deficit irrigation and/or mulching.

Insecticidal and repellent activities of the essential oil of Callistemon citrinus (Myrtaceae) against Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

The essential oil of Callistemon citrinus (Curtis) leaves was extracted by hydro distillation and tested on female and male adults of Callosobruchus macullatus (F.) for insecticidal and repellent effects. GC-MS analysis was used to identify and quantify the volatile composition of the essential oil. Results showed that 1,8-cineole (34.2%) and α-pinene (29.0%) were the major components of the oil. Callistemon citrinus oil was found to be toxic to adult insects when applied by fumigation. Responses varied according to the gender of the insect and exposure time. LC50 values were 12.88 and 84.4 μL. L(-1) for males and females, respectively. An increase in exposure time from 3 to 24 h caused an increase in mortality from 50% to 100% in males and from 15.5% to 85.2% in females, at the highest concentration (500 μL. L(-1)). The essential oil also had a repellent effect against C. macullatus in a filter paper arena test. After 2 and 4 h, 86% and 94%, respectively, repellent effects were demonstrated at the highest concentration of 0.4 μL .cm(-2). These observations suggest that C. citrinus essential oil may be usefully applied to control storage pests.