Harvest of table olives by mechanical harvesting equipment

In this work, we have evaluated the performance, of an electric comb equipped with five undulated fingers used for mechanized the harvesting of table olives. The first aim of the work was to test three different types of coating materials used for covering the fingers: Silicon (S), Vulcanized rubber (VR) and Natural rubber (NR). The diameter of the coating materials tested were 7mm (D1), 14 mm (D2), 19 mm (D3) in order to evaluate the damage of different working conditions on the intact olives. During harvesting, silicon at 7mm and 14mm resulted in the largest percentage of undamaged the fruit (67% and 65%), natural rubber 63% and vulcanized rubber at the 54%. The second aim was to evaluate the combination, in terms of the best performance, of the machines used for mechanized harvesting of table olives. Several factors have been examined: undulating fingers variation thickness, different rotational speeds and different coating materials used to reduce the impact damage on olives. From the tests on olive tree we have determined that while plastic materials (S) and (NR) appear to have a positive role in harvest quality, the vibration transmitted to the operator’s hand is great from 6.48 m/s2 for S to 6.31 m/ s2 for NR and 2.92 m/s2 for VR, respect to the materials used

La Meccanizzazione della raccolta del mirto

The plant of the myrtle in past has been always considered one marginal cultivation and of insufficient interest. Only in the last five years it has been knowledge the economic importance for the demanded crescent of liquor of myrtle, product up to now nearly exclusively in Sardinia. Therefore, new sensibility has been developed one and a greater knowledge of the importance of a deepened study more of the cultivation from the biological point of view and the point of view of one rations mechanized harvester of the berries. The aim of the work was that one to characterize an harvester of the berries from the plant, avoiding the damaging of the plant and above all of the fruits that influenced on the quality of the finished product. In this present study they are evidences the comparison between some tests of harvest in turn to obtained and carried out with two different types of harvesters some in relation to the ransom of the plants

Produzione di pane "Carasau": comparazione fra un impianto tradizionale e uno semicontinuo

"Carasau" is a typical bread of Sardinia. In the last ten years the Small-medium enterprises (SME) have aimed at improving different aspects of the Carasau processing production. One of the most important factors is related to the size of the bakeries, as it is difficult to transform a traditional processing into an industrial one, due to the high number of operations required for the production of this bread. In the present work they have been compared two different plants (traditional and industrial) for the production of "Carasau", considering the equipment, the power consumption, and some chemical-physical parameters of the final products. Il pane "Carasau" è un pane tradizionale della Sardegna. Negli ultimi 10 anni le piccole e medie imprese artigianali della Sardegna, hanno cercato di migliorare gli impianti e il processo di produzione di questo pane tipico. Uno degli aspetti più importanti è quello di trasformare un processo artigianale in processo industriale, per effetto dell'elevato numero di fasi necessarie alla produzione del pane "Carasau". Nella presente nota sono stati riportati i risultati di una sperimentazione condotta in due impianti, tradizionale e semicontinuo, al fine di valutare oltre alle caratteristiche operative delle macchine le capacità, la qualità e l'organiuazione del lavoro

Prove di disidratazione osmotica di frutti di fico (<i>Ficus carica</i> L.)

Fig fruits were subjected to osmotic dehydration by means of five different sugar syrups, in order to check the aptitude of this fruit species to this kind of processing. Osmotic dehydration was carried out at 25° and at atmospheric pressure on whole fig fruits of the local cultivar "Verde". Processing lasted 24 hours and the following dehydrating syrups were used: sucrose, glucose, fructose and two commercial hydrolysed corn starch syrups Frudex 70 and Glicosa. At fixed intervals (0, 1, 2, 3, 6, 12 and 24 hours) appropriate determinations were done on fruit pulp, in order to calculate weight loss, water loss, solid gain and normalised solid content. Results obtained clearly indicate that fig fruits show a low aptitude to be osmodehydraled, probably for their morphology and anatomy and for processing conditions used in this trial. Frotti di fico sono stati sottoposti ad una prova di disidratazione osmotica con cinque differenti sciroppi zuccherini, al fine di verificare la rispondenza di questa specie a tale tecnologia di trasformazione. L'osmosi è stata condotta per un periodo di 24 ore alla temperatura di 25°C e a pressione atmosferica su frutti interi della varieta locale "Verde", impiegando i seguenti agenti disidratanti: saccarosio, glucosio fruttosio e gli idrolizzati di mais Frudex 70 e Glicosa. Ad intervalli prefissati (0, 1, 2, 3, 6, 12 e 24 ore) sono state effettuate sulla polpa dei frutti le determinazioni necessarie per calcolare le cinetiche relative al calo peso, alla perdita d'acqua, all'acquisto in solidi e al contenuto normalizzato in solidi. I risultati ottenuti evidenziano, probabilmente a causa delle caratteristiche morfologiche ed anatomiche di questo frutto e delle condizioni operative adottate, una modesta attitudine dei frutti alla disidratazione osmotica

Essiccazione in corrente d'aria calda e conservazione di frutti della cultivar autoctona di susina "<i>Sighera</i>"

Plums of the local cultivar "Sighera" were harvested in Sardinia at the end of August, dried with hot air at 50C and 67 m3/min, vacuum packaged with a 95 μm tickness plastic film and stored for more than 270 days. Fruits have been dipped in water alone at 60°C for 20 min or in 0.025% water solutions of NaCl, potassium meta-bisulphite and potassium sorbate, respectively, before being dryed. Fresh and processed fruit were inspected for: pH, titratable acidity, total soluble solids, water activity, percent dry matter and moisture, total microbial count and vitamin C content, with the latter two at certain intervals on stored product as well. Technological means adopted turned out in a good overall appearance and taste product. In particular, blanching with potassium sorbate stabilized dried fruits from the microbiological point of view and slowed down vitamin C degradation. Susine nere della cultivar locale "Sighera", raccolte in Sardegna nel mese di agosto sono state essiccate in corrente d'aria calda (67 m3/minuto) alla temperatura di 50°C, confezionate sottovuoto in buste di film plastico dello spessore di 95 μm e conservate per la durata di oltre 270 giorni. Prima dell'essiccazione i frutti sono stati scottati in acqua a 60°C per 20 minuti o alternativamente in soluzioni acquose allo 0,025% di NaCl, metabisolfito di potassio e sorbato di potassio. Sono stati determinati sul prodotto fresco e a fine processo i seguenti parametri: pH, acidità titolabile, solidi solubili totali, attività dell'acqua, percentuale di sostanza secca ed umidità, conta batterica totale e contenuto in acido ascorbico, gli ultimi due ad intervalli prestabiliti anche sul prodotto in conservazione. Le combinazioni tecnologiche adottate hanno fornito un prodotto finale di aspetto e gusto gradevole ed in particolare la scottatura con sorbato di potassio ha conferito ai frutti un'ottima conservabilità in condizioni di mercato ed un rallentamento nella degradazione della vitamina C

Response of three Sardinian olive cultivars to greek-style processing

The response of three Sardinian olive cultivars to processing as table olives with the Greek-style was evaluated. “Bosana”, “Manna” and “Sivigliana sarda” olives were characterised from the marketing, technological and chemical-physical point of view and brined with 8% NaCl. Fermentation was carried out according to the anaerobic method for 150 days. At fixed intervals main brine and flesh parameters were monitored. Evolution of brine chemical parameters showed yeast fermentation. Oleuropein decreased greatly in the flesh after 20 days and totally disappeared in “Bosana” after 90 days. Sensory determinations resulted in good taste and texture for the three cultivars, with “Bosana” being preferred. Gassy alterations were negligible, while shrivelling was not detected

Comparison between an in-flight UAV refueling platform and ground-based vehicles for plant protection product distribution

Limited payload range generally caused by the poor weight-energy performance, flight autonomy, manual replacement of spent batteries, and agrochemical tank refilling procedure are limiting factors affecting UAVs' agrochemical distribution. This work aims to evaluate the effectiveness of agrochemical distribution by a UAV operated by a reactive robotic payload replacement (M.A.R.S.) platform and compare it with ground-based distribution systems in a viticulture scenario. The work considers a hybrid technology UAV with an onboard gasoline-powered electric generator, characterized by an "in-flight" refill of fuel and agrochemicals without the need for landing. Results report a limited ability of the aerial system to cover large areas with a single tank, balanced by 2.3 minutes to perform a tank refill, significantly less than ground-based distribution systems. The volumes of plant protection products delivered per hectare by the aerial platforms are more suitable for low-volume treatments but they can be logistically advantageous because of their rapid response and lack of impact on soil and crops. The proposed approach represents a solution for UAV implementation for spraying operations on vineyards and opens new scenarios for large areas treatments

Hand arm vibration generated by a rotary pick-up for table olives harvesting

The manual harvest of olives is one of the most expensive operations in the table olives production, but the use of the electric hand-guided machines triples the productivity.  The development of these new machines leads to changes in the harvesting methodologies and in the operator’s working behavior.  These items may also affect the hand-arm vibration (HAV) transmitted to the operators during the work.  Aim of this study is to evaluate the hand-arm vibration transmitted to the operator using an experimental electric labor saving machine with rotary combs with teeth of different dimensions covered by silicon to minimize the damage to the drupes.  Moreover, the olives removal forces have been analyzed to understand if the force necessary to detach the drupes is correlated to the vibration levels transmitted to the operator’s hand arm.  With this type of hand held olive harvester, it has been found that higher is the fruit removal force, higher are the measured vibration levels.   Keywords: HAV, portable olive shakers, rotary pick-up, table olive

Essiccazione di cultivar di susino del germoplasma della Sardegna mediante l'utilizzo di trattamenti di deceratura

Four cultivars of plums of Sardinian germoplasm have been dried with forced air at 65°C. Fruits have been subjected to dewaxing treatments before processing, in order to remove the wax layer on the fruit surface and reduce the dehydration duration. Dehydration kinetics and some physical-chemicals parameters (pH, total soluble solids, dry matter, water activity and colour) have been determined on fresh, while processing and processed fruits. Results of the present study will be discussed. Frutti di quattro cultivar di susino del germoplasma locale sono stati essiccati in corrente d'aria forzata alla temperatura di 65°C. I frutti prima di essere trasformati, sono stati sottoposti a dei pretrattamenti coadiuvanti di deceratura, al fine di eliminare lo strato ceroso presente sull'epidermide e ridurre i tempi d'essiccazione. Sui frutti freschi, in trasformazione e su quelli essiccati, sono state determinate le cinetiche d'essiccamento e i seguenti parametri chimico-fisici: pH, contenuto di solidi solubili totali, sostanza secca, attività dell'acqua e colore. Nel presente lavoro saranno discussi i risultati relativi alla sperimentazione