Chemical and Microbial Differences in Dried Apricots Containing Sulfur Dioxide at Different Levels (in English)

Abstract

This study was conducted to evaluate the effects of different sulfur dioxide (SO2) concentrations (0, 188, 452, 791, 1034, 1236, 2899 and 3864 mg SO2/kg) on the physical, chemical and microbiological qualities of dried apricots (DAs). Non-sulfited DAs were evaluated as a control group. Strong correlations were determined between SO2 concentration with pH (r = ‒ 0.913), titratable acidity values (r = 0.983), browning values (r = – 0.981) and β-carotene contents (r = 0.822) of DAs (P<0.05). The number of total psycrophilic aerobic bacteria (TPAB), lactic acid bacteria, yeast and mold, xerophilic mould, Staphylococcus spp., and total Enterobacteriaceae were below the detection limit (<0.6 log cfu/g) in samples containing SO2 even at the lowest level (188 mg SO2/kg). Although 188 mg SO2 per kg of DAs is sufficient SO2 concentration with respect to browning color and microbial load right after drying, DAs should contain minimum 791 mg SO2/kg to protect the initial β-carotene content.

Keywords

• Dried apricots, SO2 level, browning, β-carotene, microbial load

Farklı Düzeyde SO2 İçeren Kuru Kayısılardaki Kimyasal ve Mikrobiyel Farklılıklar (İngilizce)

Abstract

Bu çalışma; kuru kayısıların, fiziksel, kimyasal ve mikrobiyolojik özellikleri üzerine farklı kükürt dioksit (SO2) konsantrasyonlarının (0, 188, 452, 791, 1034, 1236, 2899 and 3864 mg SO2/kg) etkisini değerlendirmek amacıyla yürütülmüştür. Kükürt içermeyen kuru kayısı örnekleri kontrol grubu olarak değerlendirilmiştir. Kuru kayısıların içerdiği SO2 konsantrasyonu ile pH (r = ‒ 0.913), titrasyon asitliği (r = 0.983), esmerleşme değerleri (r = – 0.981) ve β-karoten miktarları (r = 0.822) arasında güçlü korelasyonlar tespit edilmiştir (P<0.05). En düşük düzeyde SO2 içeren (188 mg SO2/kg) örnekte dahi toplam psikrofilik bakteri, laktik asit bakterisi, Staphylococcus spp., toplam Enterobacteriaceae, kserofilik küf ile toplam küf ve maya sayıları tespit limitlerinin (<0.6 log kob/g) altındadır. Kurutma sonrasında 188 mg/kg düzeyindeki SO2 konsantrasyonu, esmer renk ve mikrobiyel yük açısından yeterli olmasına rağmen, başlangıçtaki β-karoten miktarını korumak için gerekli olan en düşük SO2 konsantrasyonu 791 mg/kg’dır.

Keywords

• Kuru kayısı, SO2 düzeyi, esmerleşme, β-karoten, mikrobiyel yük

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