Telegraph Hill table olives

June 2006
Telegraph Hill started with olive tree plantings at Havelock North 10 years ago, by Rose Gresson, a dietician by training. The first fruit came off those trees five years later and was processed into oil, with some experimentation with table olives.

Telegraph Hill now has 2000 olive trees in five varieties, plus another 260 younger trees around the new purpose-built olivery in Howard St, now open to the public.

The varieties are Barnea, Manzanillo, South Australian Verdale, Frantoio and Picholene olives. The company is now a nationwide distributor of olives, extra virgin olive oil and olive products. It takes in first grade olives from other producers for the table fermentation process.

Geoff Crawford has come into the business with marketing and sales skills.

Future development plans include a retail store, tours, culinary classes and exporting.

Table olives

New Zealands olive industry, based mainly on Barnea variety, is aimed at extra virgin oil production, because of climatic factors which produce very high quality oils, internationally acclaimed. In 2002 estimated NZ production was 365 tonnes and 49,500 litres of oil. Only 5% of worldwide olive oil can be classified extra virgin whereas most of New Zealand oil qualifies as extra virgin.

Telegraph Hill was the first in NZ to develop a table olive specialisation, which requires much more fermentation and processing time, plus food grade facilities.

Production in 2005 was 17 tonnes of olives, and for the 2006 harvest the target is 30 tonnes of Telegraph Hill olives and consignments from other growers. Telegraph Hill pays about double for the top quality olives, suitable for table use, compared with the returns available from oil. The mix is about two-thirds black and one-third green olives.

Black olives require several more weeks ripening on the trees. Table olives must the highest grade, without blemish, cuts or frost damage, and hand-picking is the best, plus some from new shaking machines.

The market in New Zealand is estimated at about 400 tonnes of table olives imported annually and it is growing at 20% consumption increase.

Demand for Telegraph Hill olives is increasing steadily, as Rose and Geoff put a lot of time into food shows, farmers markets and promotion on the internet. The table olives are stocked in Wellington and Auckland supermarkets, at Sky City and in Koru Lounges.

Processing

Table olives are pickled in brine for six to 12 months to draw out the bitter tasting oleuropein compound and make them palatable. The salt concentration is 6-10% and the fermentation takes place in largely anaerobic conditions, to prevent the growth of undesirable spoilage microorganisms. Additions, including acetic acid, sugar and starter cultures of lactic acid bacteria can be added to the brine, to adjust the conditions in the brine to suit the growth of both the lactic acid bacteria and desirable yeasts.

Once pickled, Telegraph Hill produces six table olive products in different sized packages: natural, green, lemon flavoured, garlic, smoked and roasted. It also produces olive salsa, mustard and tapenade.

Another variation in the production is pickling the olives in organic dry salt.

The best variety for table production currently is Manzanillo. Kalamata would be ideal when available, but those trees take a long time to fruit. Large size Barnea are also used.

A possible next step in quality would be to get a light-aided grading machine which would separate green and black olives, remove soft fruits and deliver more consistency, but that would be a large investment.

Geoff has developed many of the processing steps with good old NZ ingenuity.

EIT project

Microbiology Lecturer Carolyn (Cryn) Russell from Eastern Institute of Technology, Taradale, has worked with Telegraph Hill on aspects of the fermentation for the past 12 months. Various aspects of fermentation were monitored and changed during the processing of a tonne of olives in 2005. Sensory analysis at the end was used to detect any differences between treatments.

Levels of additives like salt (brine concentration) acetic acid, sugar and starter culture were varied. Samples were taken during the year to test for microbes, including lactic acid bacteria, spoilage microorganisms and yeasts, and run chemical tests including assessing the level of oleuropein bitterness compound, most of which has to be removed for the olives to be palatable. Other analyses included testing for the level and types of acids and sugars, and salt level through the fermentation.

Another issue at present is that salt levels stratify in large containers of fermenting olives. They will need to be mixed without introducing too much air into the anaerobic pickling. This work was carried out with the assistance of Food Hawkes Bay.