Abraham Izak Perold, viticulturalist, was the son of Isaac Stephanus Perold, a wine farmer, and his wife Johanna Helena Brink. After matriculating at the Boys' High School, Wellington, in 1898, he continued his studies at Victoria College, Stellenbosch. As a student he took the initiative in founding the Victoria College Scientific Society in December 1900. On 7 March the next year he read a paper before its members on "Plant food and its introduction into the soil". He was awarded the degree Bachelor of Arts (BA) by the University of the Cape of Good Hope in 1901, and received a bursary. Early the next year he left for Germany to continue his studies and was awarded a doctoral degree in chemistry by the University of Halle an der Saale in 1904. His thesis was titled "Ueber die Verbindungen der Wolle mit farblosen Aminen und Saeuren" (On the compounds of wool with colourless amines and acids; Halle, 1904, 39 pp). After spending a year in Paris, where he learned French (he was fluent in Dutch, English and German, and knew some Spanish, Portuguese and Italian) he returned to the Cape Colony in September 1905 and early in 1906 took up an appointment as assistant in chemistry at the South African College, Cape Town. That same year he wrote his first scientific publication, "Di wijnbouw in Frankrijk en hier" (Viticulture in France and here; Ons Land, 1906; reprinted, Cape Town, 1906, 13pp).
At the beginning of 1907 Perold was appointed government viticulturalist of the Cape Colony and sent to Europe for two years to study viticulture and wine making. He spent time at experimental stations such as Geisenheim (on the Rhine near Wiesbaden, Germany) and Waedenswil (on the shore of Lake Zurich, Switzerland), and visited other countries in Europe and north Africa. While in Algeria in 1909 he came across the Barlinka variety of table grape, which he described for the first time and introduced to South Africa with great success - it became South Africa's dominant export grape. In later years he introduced many more varieties of vine to South Africa. During his stay overseas he published "Untersuchungen ueber Weinessigbakterien" (Investigations into wine vinegar bacteria; Centralblatt fuer Bakteriologie, 1909).
After his return to South Africa in 1910 Perold became head of a government viticultural research station on Bellevue, a farm in the Paarl district, with the aim to promote table grape exports. Two years later he was appointed principal of the School of Agriculture at Elsenburg, near Stellenbosch, while retaining his position as government viticulturalist in the Department of Agriculture of the Union of South Africa. In spite of his administrative workload he managed to continue research in viticulture and wine making, particularly on the propagation of cultivars, soil preparation, and vine diseases. In 1914 the Wine Institute building was completed at Elsenburg, marking the beginning of systematic viticultural research in South Africa under Perold's leadership. Throughout his career he did much to place South African viticulture and wine making on a scientific footing, among others through scientific and semi-popular publications. Soon after his return to South Africa he wrote "The principal diseases of our vineyards" for the Agricultural Journal of the Cape of Good Hope (1910). His articles in the Agricultural Journal of the Union of South Africa dealt with, among others, "The principal micro-organisms playing an important part in the making and maturing of wine" (1911), "The manuring of vineyards" (1911), "American stocks for Cape vineyards" (1912, in 3 parts), "The co-operative selling of grapes" (1912), and "The establishment and cultivation of a vineyard" (1913, in 3 parts). He also published a pamphlet on the renewal of vineyards in calcareous soils with appropriate American stocks (Department of Agriculture, Bulletin 48, 1913). A series of five articles in which he promoted the establishment of agricultural schools, written for the magazine Ons Land (May 1914), was republished as Terug naar die land... (Cape Town, 1914, 13 pp). He also wrote a comprehensive article, "Viticulture in South Africa", that was published in the International Review of the Science and Practice of Agriculture (1916, 32 pp).
Perold became a member of the South African Association for the Advancement of Science in 1910 and contributed the following papers to its Report: "Cape wine levures [yeasts] and their use in wine making: A preliminary study" (1912) "Some preliminary investigations into the chemical composition of certain vineyard soils in the Montagu and Robertson districts" (with D.C. Crawford; 1914), "Agricultural education in South Africa" (1917), and "The volatile acidity of wine..." (1917).
In August 1917 he was appointed professor of viticulture and oenology (the study of wines) at the University of Stellenbosch (the successor to Victoria College), where he successfully introduced tertiary education in viticulture in South Africa. He also served as dean of the Faculty of Agriculture. In 1926 the School of Agriculture at Elsenburg amalgamated with the Faculty of Agriculture to form the Stellenbosch-Elsenburg College of Agriculture of the University of Stellenbosch. He remained in his academic post until January 1928. During this period he published "Ondersoekings omtrent moskonfyt" (Investigations about moskonfyt, Annals of the University of Stellenbosch, 1923, 15 pp); "Enologiese ondersoekings" (Oenological investigations; Ibid, 1929, 27 pp); A treatise on viticulture (Stellenbosch, 1927, 606 pp; also in Afrikaans), which was well-received also in other countries; and some contributions on the problem of alcohol abuse (1920, 1922, 1924). He was also one of the four editors of the Populair-wetenskaplike leesboek (Popular science reader; Cape Town, 1919-1920, 6 vols).
In January 1928 Perold was appointed as oenologist and research scientist of the Co-operative Wine Farmers' Association of South Africa (KWV) in Paarl, where his expertise contributed much to the growth of the association's wine exports. His last major publication was Historical notes on the Cape wine industry: The wine book of South Africa (Stellenbosch, 1936). A few years later he died of a heart attack. An exceptionally intelligent man, he deserves to be remembered as the father modern viticulture and wine-making in South Africa.
As a strong supporter of Afrikaans Perold was a foundation member of the Afrikaanse Taalvereniging in November 1906 and for many years was a member of the Akademie vir Taal, Lettere en Kuns. He was a member of the council of the University of the Cape of Good Hope from 1913 to 1918. In 1908 he married Bertha Elisabeth Mueller of Halle, with whom he had six children. Two of his sons became prominent academics. His second marriage, in 1931, was to Marta Winzer.
